"FACTS ��u FIGURES�'

CONr.ERNING

COAL W ASH'ING

BY THE

LUHRIG PROCESS:

WITH NOTES ON THE MANUFACTURE OF

COAL BRIQUETTES. Press of Mortimer L. Williams, No. 28 Elm Street, New York CONTENTS.

-'lads anh ligUfU" concerning «oal �asVing.

PAGE.

INTRODUCTION, 9

THE LUHRIG COAL WASHING PROCESS, It

LIST OF COAL WASHING PLANTS ERECTED IN

EUROPE BY C. LUHRIG PREVIOUSLY TO

DECEMBER 3 I ST, 1889, 18

LIST OF ORE DRESSING PLANTS ERECTED BY

C. LUHRIG PREVIOUSLY TO DECEMBER 3 t ST, 1889,

DESCRIPTION OF A NEW COAL WASHING PLANT

AT FERDINAND GRUBE, KATTOWITZ, IN UPPER SILESIA,

SOME 01' THE ADVANTAGES OF THE LUHRIG

PROCESS, 39 4 PAGE.

REPORT ON L'lJHRIG'S SYSTEM OF COAL WASHING, BY PROFESSOR KREISCHER (ROYAL SCHOOL OF MINES, FREIBERG), 47

ESTIMATES OF PROFITS, 54

(A) Saving in the Pi�, 54

(B) Saving in using up Mixed Coal, . 54

(c) Saving in Coking, 55

(D) Increase of Lump Coal, 55

(E) Recovery. of Bye-Products (Pyrites), 56

Total Savings, 56

ESTIMATE OF PROFITS AT HEINITZ COLLIERY, SILESIA, 57

ApPENDIX:-

I.-TESTS MADE AT BRUCKENBERG PIT

No. II., NEAR ZWICKAU, 60

n.-TABLE OF RESULTS OF DAILY ANAL­

YSES FOR ASH IN COKE MADE AT BOCHUM, 66

COAL WASHING FOR COKE MAKING, . 68 5

�tnttS .an iqe �bnnfadutt .at 'Dal �riqutfttS:

PAGE.

INTRODUCTION, 77

NOTES ON COAL BRIQUETTES, 79

ESTIMA TE OF PLANT, •

DESCRIPTION OF MESSRS. MOWLL & MESSENGER'S

MACHINE, 83

TABLE OF VARIOUS TYPES OF BRIQUETTE PRESSES, 85

TABLE OF COMPARATIVE PRICES FOR 1885,. 86

DESCRIPTION OF PRESS FOR THE MANUFACTURE

OF SMALL NUT BRIQUETTES,

COST OF PRODUCTION,

INTRODUCTION.

�t)f"t)f"t)f"t� . 11I�\,§"IIIIIIIIIIIIII"iI�I�"HE arm of this is to direct the +-: ...T..... ::::.+ pamphlet (I� � �I; public attention to the important 'subject ��III� !II� of coal washing, the numerous advan­ �i! t li� tages connected with the use of clean. 1111111111111111111111111111111111111111 ...... )(+ ;(+ ;(+ )I'+� coal, and a cheap and economical pro- cess of cleaning it.

THE problem of coal washing is an extremely com- plicated one, and the few words on the subject contained herein are merely intended to awaken the interest of the coal owner, the coke manufacturer, and the iron and steel master.

IT is to be hoped that the Report by Professor Kreischer, an authority on all minmg matters, and especially on coal washing and ore dressing, will be of interest to mining men. Although this Report was written in 1882 it will be found to contain some quite interesting matter. Since the issue. of this Report the Llihrig System has undergone a great many improvements.

THE description of the plant at Kattowitz, which contains many late improvements, sives a fair idea of the process.

MOST of the figures and tables are taken from practical tests made by Professors Kreischer and Nonne.

THE list of plants erected, and the map of the spread of Plants built on the Llihrig process has been revised by Mr. Llihrig himself, and is correct up to the 31st December, 1889.. 9

The Process has been extensively adopted at the largest collieries in the following countries:-

ENGLAND

SCOTLAND

FRANCE

BELGIUl\I AUSTRIA

HUNGARY

RUSSIAN POLAND

RHEINISH PRUSSIA

WESTPHALIA

SAXONY

UPPER SILESIA

LOWER SILESIA

BOHEMIA

HANOVER

Plant is now being erected in­ GREECE

ASIA MINOR

ALGIERS

144 complete plants on LUHRIG'S System have been erected by him and working previous to December 31st, r889. (See accompanying Map.)

TIlE LUHRIG

COAL WASHING PROCESS.

the last few years coal has . mining - made it really necessary for most collieries - J coal ��! I�IIURING� to be supplied with good washing plant, and the work of the coal washing engineer has been made more and more difficult and complicated in proportion. WHILST formerly colliery managers built coal . washing plants according to their own notions and ideas, the erection of such plants is now generally put into the hands of a coal washing specialist. A G REAl' deal of machinery for use in the mechanical separation of coal is made and sold, but the arrangement of such machinery, and the general and economical disposition of it, is generally looked upon as a secondary matter by the manufacturers. In short, there is usually a 1MIlt of that systematic arrallge- men: 'which 'would b,-illg about a process sltit(lble fiir the economicai cleansing of the coal. THE perfecting of such a process has been the ex- clusive work of Mr. C. Llihrig during the last 25 years, and he has been eminently successful in the United Kingdom and on the continent of Europe, as both the map and list of plants erected will show. T HIS process is the result of a long and varied experience with some of the most dirty coal on the continent of Europe, and is on the gradual reduction system, that is, if the washed coal is to' be �oked it is not all crushed up in a dirty state, but gradually broken up, the shale being automatically separated from the coal by degrees. T HE process essentially consists of:-

Dry separation of the run of the mine, that is, the mechanical separation of the slack or dross from the lump coal.

Coal which passes between the bars of a screen about three inches apart or through a reciprocating screen of three inch to four inch mesh, is generally treated in the washer.

In many cases the lump passes on to picking and loading bands, where the shale and interstratified pieces are picked out by hand. 13

All larger pieces of coal, when interstratified with shale or mixed with pyrites, are broken and again passed over the screens for reseparation. Sl'jaratioll of the slack or dross' by screening, the dross is raised into revolving screens for the purpose of sizing the coal for the production of nut, pea and fine coal.

Tprashillp,- the different sizes of nut coal coming from the revolving screens, each on separate machines, so that each machine only works up coal 'of uniform size.

Cmshillg the mixed or finely interstratified coal (separated by washing from the pure coal and clean refuse), for re washing on separate machines. Gradillg the fine coal from the �Is downward from the screens, and that carried by the water from the nut coal washers, into different classes ac­ cording to specific weights. TVashiizg each different grade or class of fine coal on separate washers especially constructed for the treatment of fine coal, their work being per­ fected by the help of feldspar; this was first employed by Mr. Liihrig in coal washing ma­ chinery, and has given very satisfactory results.

The 1,{,(0'Z'e1), of sludge, or "schlamm," which is so difficult to retain and which often contains exactly what is' essential to coking in the case of a coking coal. This is done by means of automatic and continuous sludge recovering machinery. Filterillg tlte 'water used in washing, and cleaning it to such an extent as to enable its re-use again and again. TIle- automatic transport of the vhrious products, nut, pea, pearl and fine coal, al,so of refuse, both fine and coarse.

Ecconery of bye-prodllcts, as, for instance, pyrites or brasses, which in many of Llihrig's plants pays the cost of labor.

Arrangements are also made for automatically storing a considerable quantity of coal, the hoppers being so arranged that a large quantity

of coal can be loaded in a short time.

The dry separating portion of the plant is con­

structed so as to make as little "smalls" as possible, the screening and loading arrangements being economical, efficient and automatic.

The washing arrangements are such that as much dean nut coal can be extracted as possible, and that tIlref prodllcts can be made by each machine, viz., clean nuts, seconds or nuts inter­ . (finely stratified with shale), which are raised, crushed and rewashed, and c1ean refuse. I N all of Ltihrig's plants there is a marked desire to> avoid crushing all the coal, that is, the dirty and clean coal together; this is so often done at collieries using single apparatuses. Such a system always leads­ to the productionof a great deal of unnecessary fine or dust coal, and consequently to loss of coal in the­ washed-out refuse; unless the coal is very finely inter­ stratified it is always washed previous to crushing for coking. IT should be borne in mind that it is not claimed that �his is one machine suitable for every class of coal, but that it is a process 'which call be so arranged as to meet the requirements and local conditions of eaclt coi/iery. The nature of the coal to be treated is always taken into account, also the purpose for which it is. intended to be used. IT follows that every plant is different and that copying and imitation of previously carried out designs and plans is generally faulty and disappointing. MOREOVER, success does not alone depend upon machines and apparatus, which can be made at almost any engine works, but upon the process and the system upon which the whole plant has been built and is operated. AT the same time, every part must be easily accessible, open to supervision and under complete control. IT is not possible to enter into a full discussion on this process of coal washing, but only to indicate the general principles upon which it is based; suffice it therefore to say that the process is automatic, continuous, that the cost of working is almost only nominal, and that it has been adopted by the largest and most important collieries in Europe, as will be seen by the appended map and list.

THE chief points worthy of notice in the Ltihrig system of coal washing are:-

The process is automatic and continuous. The cost of working is almost nominal.

The quantity of water necessary is small. The percentage of lump coal. is considerably in­ creased by careful handling of the coal.

The value of nuts and peas is considerably raised.

The fine coal can all be saved and used for coke

manufacture, or for making briquettes.

Settling ponds are entirely done away with, the

" " sludge, or fine coal, being recovered by means of automatic sludge recovering machinery. The whole plant works with uniform precision,­

whether the coal to be treated contains 5 or 25

per cent. of foreign matter. The loading arrangements are planned for the purpose of storing considerable quantities of washed coal, an ad vantage much appreciated when \yagons are scarce.

Bye-products, such as pyrites or brasses, can be recovered.

Coke made from the washed coal IS increased in

value. THE following guarantees are generally given:­ The quantity the plant is capable of treating. The cost of washing per ton of coal. The saving in wages over other processes. The percentage of ash in washed coal. The percentage of coal left in the washed out refuse.

The reco\-ery of the sludge from the water. The automatic sizing and washing of coal from five inches downward without hand picking. V ERY often coal from seams with a band, or badly interstratified with shale, is left in the pit; this coal can often be raised at a nominal cost, and, treated by this process, good marketable nut, pea and fine coal beiJ?g automatically produced. T HE following is a list of coal washing plants on the LUhrig system erected previous to 31st of December, 1889. 18

LIST OF COAL WASHING PLANTS

ERECTED IN EUROPE ON THE LUHRIG SyS­

TEM BEFORE DECEM.BER 31St, r889.

Capacity Percentage of Ash. in Tons No. DESCRIPTION OF PLANT. per day (10 hours) I Unwashed Washed

SILESIA.

Vereinigte Gliickhilfgrube; Waldenburg 500 r 71 4 2 Silesian coal and coke works; Gottesberg 500 16} 4

3 Do. do. 400 J6} 4�

4 Do. do. 500 I7 4t

5 Do. do. 250 J7 } 4t 6 Do. do. 280 161 41-

7 c. v. Kulmiz, coke works ; Rothenback h/Cottesberg 500 I7} 3i

8 Theresienschacht: C ii s a r- Grube; Waldenberg ; Comere, Krister 500 17 } 4

9 Paulschacht, v. Kramsta. Waldenberg 400 r6} 4-l

10 Orzeche; o berschlesische Aktien ( �esellschaft f u r

Bergbau 750 J6t 41.-l.

I [ Do. do. 750 I6}- 4-

12 Friedenshoffuunggrube ; Hermsdorf b Waldenburg 750 16 � 4t

13 c. v. Kulmiz, coke works, ... 1 Rothenbach b-Cottesberg 500 I7't ..)2

14- Heinitzgrube; Beuthen 1,250 16t 4.- Capacity Percentage of Ash. in Tons No. DESC RIPTIOl\' OF PLANT. per day (10 hours) Unwashed.

---1------__------I � I

IS Redenhutte : Zabrze i 750 J6� .. d J6 Deutschlandgrube; Graf Guido: I Henkel von Donnersmarck S chwientochlowi tz 1,250 17 } 4t 17 Guidogrube; Graf Guido Henkel von Donnersmarck ..,1 Zabrze 1,250 Ilt .)2 ..,l_ 18 Borsigwerk; Oberschlesien 300 lIt .)1 19 Emmagrube; Oberschlesien 1,250 13i 3} 20 V. Tide Winckler; Myslow .. itzgrube 1,5Po 9: 2� 21 v. 'Lide Winckler; Ferdi .. nandgrube 1,750 9)· 2� ..,.., Cons. Wenzeslausgrube; N eu .. ..,1. rode .:i0o 10 ,)4 23 Friedenshoffnunggrube; Hermsdorf; dry separation 300 24 Abendrothengrube ; Gottes .. berg; dry separation 150 25 Heinitzgrube ; Beuthen ; coke ovens, 3 I ovens 26 Wenzeslausgrube; Neurode; coke ovens, 30 ovens

SAXONY.

27 Forstschacht: Oberhohndorf ; I Zwickau I 500 25t 5� ! 28 Briickenbergschacht r1.; Stein .. ..,..,1 kohlenbauverein Zwickau 500 -')J 5't 29 Do. do. 500 221 4} 30 Briickenbergschacht 1.; Stein .. I kohlenbauverein Zwickau 500 2d 51 31 Vereinsgluck ; Steinkohlen- Actiengesellschaft Olsnitz 500 ..,.., 4 20

Percentage of Ash. . '. Capacity I in I'ons N I DESCRIPTION OF PLAKT. per day 0'11 (10 hours) Unwashed. Washed. ----i------, I

• I 32 I Herscheischacht; Zwickau 500 I 33 Schaderschacht; Oberhohu­ dorf, Zwickau 500 34 Falkschacht, Zwick au 500 35 Wilhelmschacht 1.; Ober- hohndorf; Zwickau 500 36 Wilhelmschacht II.; Zwickau 500 37 Hedwigschacht; Zwickau 500 21 38 Victoriaschacht ; Lugau 500 39 Idaschacht; Hohndorf 500 40 Deutschlandgrube; Olsnitz 500 41 Vereinsgluck ; Olsnitz 500 42 Hedwigschacht; Olsnitz 500 43 Konigl. Sikhs. Steinkohlen- werk Oppelschacht im Plau-l enschen Grund 500 44 Konigl. Sachs. Steinkohlen­ werk ; Carolaschacht im Plauenschen Grund 500 Gottes Segen; Lugau 500 Kaisergrube ; Gersdorf 500 Pluto & Merkur ; Gersdorf 500 Sachs. Eisenindustrie; Pirna 300 Berkerschacht : Hanichen 500 Bruckenbergschacht IV.; Zwickau 600 51 Bruckenbergschacht I I.; Zwic­ k au (rebuilt) 600 Graf Lippe, Kleinsaubernitz dry separation ISO 4 53 Kaisergrube, Gersdorf; Coke Ovens, 35 Ovens 21

Ash. Capacity Percentage of 111 Tons o. DESCRIPTION OF PLANT. I II per day I I (10 hours) i Unwashed. Washed. 1--1

RHEINISH PRUSSIA.

54 Wolfsbank, Essen 500 9� 4} 55 N euwesel; Essen 400 101 4';j 56 Kohlscheidt; Aachen 400 II:! 4 �- 57 Mariagrube; Hauptschacht; 1"=i Hangen 1,250 J I 4t 58 Do. do. Sao 131 4t " 59 Grube Neu Laurweg" ; Kohlscheidt 500 141 4} 60 Franzschacht; Alsdorf 1.250 13'! 4�

WESTPHALIA

I'" :1 61 Friedrich Joachim, Kray 500 -I 3t "I 62 Bonifacius; Kray 500 12,\ J I 63 Bochumer Verein in Bochum 750 II} 3t 64 Hansa, Dortmund 400 9t 21 ..., :.1_ 65 Zollern, Marten, Dortmund 750 91 -! 66 Julius Philipp; Bochum 750 101 3 67 Constantin de r Grosse; / .,;{ Bochum 250 loi J! 68 Carolinenglnck ; Bochum 500 lOt 3t 69 Holland; Wattenscheidt 750 IIi 4 ,:1. 70 Hasemoinkel; Dahlhausen 500 1 --I 41 71 Schleswig; Herder Bergwerks Verein; Dortmund 500 131 41 72 Do. do. 500 13 4t 73 Arnoldschacht; Dortmund 750 13� ·d Arnaliaschacht Dortmund 1:2 74 , ; 750 � 4}- 22

Capacity Precentage of Ash. in -Ko.1 DESCRIPTION OF PLANT. Tons per day (10 hours) Unwashed. Washed,

I Prinz von Preussen : Dort- 7 S ' mund 200 II 76 J acobschaft; Dortmund 200 Id 77 Rhein-Elbe; Gelsenkirchen; Dry separation 400 78 Alma do. 300 79 Ewald do. 400 80 Engelsburg cons; Bochum 2S0 81 Priisident cons; Bochum 2S0

HANOVER.

82 Krll1igl. Preuss. Steinkohlen- werk; Obernkirchen soo 14 3� 83 Stadt. Osnabrucker S t e i n- kohlenwerk SOO I7t S1 84- Konigl, Preuss. Steinkohlen- werk Borgloh ISO IS} 6\

AUSTRIA-HUNGARY.

8S Heinrich-Schacht; Mahrisch Ostran 2S0 171 S1 86 Erbstolln; Prinz Schaumburg Lippe'sches Bergamt soo 1 6'1_I 4� 87 I dastolln ; do. 800 I7k 4t 88 Erbstolln ; do. 1,000 I6} 5� 89 Victoriaschacht ; Funfkirchen soo "" 8} 90 Dr. Strousberg'sches Stein- kohlenwerk ; Dobrin 750 I71 6\: 91 Miroschau ; Rokyzan 300 161 5� 23

Capacity Percentage of Ash. in No. DESCIUI'TWN OF PLAl'T. Tons per day I (IO hours) Unwashed. Wa�hed.

9:! Fohnsdorf b/Tudenberg 750. 161 93 V. Rothschild Wittkowitzer Eisen & Stahlwerke in Wittkowitz 750 21 7

BELGIUM.

9-1- Hasard 300 l"a,).l 4 95 Bascoup 500 14 41 96 Boussu 750 J2 � 4 97 Ressaise 750. J5l 4� 90 Fontaine I'Eveque 750. J4t 5� 99 Haine St. Pierre 750. I31 4::

FRANCE.

:; 10.0 Haveluy ; Anzin 750. T4} 41" 101 St. Louis; Anzin 750. I6:t 5!

. 102 Renard; Anzin 750. lIt 4 10.3 Trelis; Alteis 400. 13� 41 10.4- Meurschin : Carvin 40.0. 12 4 105 Noeuse r,:!5Q rd 51 106 Aniche 750. II� 4 107 Champagnac 40.0. IQ� 3k 108 Blanzy 350. 141- 4t 109 Flers Escarpella 40.0. 121 4t ;j [10 Anzincourt 50.0. II .� -I Percentage of As�. . I DESCRIPTION OF PLANT. T;)���tsY --- • '----,'I' per day l'iO'1 (10 hours) Unwashed. Washed, i I --1------, 1------

RUSSIA-POLAND.

I II Graf von Renard & Eulen- burg; Renardschacht; Sielce 1,250 16} -t! 112 Graf von Renard & Eulen- J ohannaschacht : burg; . Sielce 300 161 4! 113 Fanschacht : (L a pin sky) ; Steinkohlenwerk Dom- browa, Warschau 300 q� 5t

GREAT BRITAIN.

114 Bardykes Colliery, Newton; Messrs. Merry & Cuning- hame, Glasgow 800 "" -t} lIS Motherwell Colliery, North M otherwell; Messrs. Merry & Cuninghame, Glasgow 1,500 211 41 JI6 Fife Colliery Company; Leven 500 rS� -t II? Denaby Main Colliery Com- pany Limited, Mexbro', 20 ,,1 Rotherham 500 JI" JlS Ellenbro' Colliery, Maryport ; Hematite Iron and Steel Company, Limited, Mary- port 500 23} 51 LIST OF ORE DRESSING PLANTS ERECTED ON THE LUHRIG SYSTEM, PREVIOUS TO DECEMBER 3ISt, I889.

Capacity in Tons No. DESCRIPTION OF PLANTS. MINERALS. per day (10 hours)

Central Ore D re s sing Silver, lead, copper, Plant, built for the Fiscal arsenic and pyrites Royal of S a x 0 n y a t Himmelfahrt, Freiberg

120 Grube Jungehohe Birke, 50 Silver, lead, copper, built for the Fiscal Royal arsenic and pyrites at Frieberg, Saxony

121 Grube Beihilfe, built for 25 Silver, lead, copper, the Fiscal Royal at arsenic and pyrites Freiberg, Saxony :�

122 Grube Churprinz Fried­ Silver, lead, copper, rich August, for the arsenic and pyrites Fiscal Royal at Frei­ berg, Saxony

123 Mordgrube, built for the Silver, lead, copper Fiscal Royal at Frei­ and pyrites berg, Saxony

124 Grube Gute Gottes; 50 Gold, silver, lead' Scharffenberg Meissen, and zinc Saxony

125 Scharwazenburg, Saxony 25 Lead and zinc blend

126 Aschenbachschacht, for 400 Kali salts the Fiscal Royal of Prussia, at the salt mines, Strassfurt

127 Douglashall, built for the 50 Kali salts Fiscal Royal of Prussia at Strassfurt, Prussia No. DESCRIPTION OF PLANT. r;¥;�J MINERALS. per day (10 hours)

128 Herzgol. Anhlt'sche salt 50 Kali salts mines Leopoldshall

129 Grube Willibald, for the Silver, lead and zinc Stollberg Mining and blend Zinc-smelting Co., Ramsbeck, Westphalia

130 Silberart; Siegen West­ 100 Silver, lead and py­ phalia rites 131 Victoria 1. in Harz 20 Do.

132 Victoria 11. in Harz 10 Do.

133 Rhona, Silesia Pyrites

. 134 Palmiken ; Konigsburg, 100 Amber East Prussia 135 Boleslaw; Russian Poland Lead, galena and zinc hlend 136 Dombrowa; Russian 100 Do. Poland

. 137 Praga; Russian Poland 100 Steel, slag, cinders 138 Grube Gute Hoffnung, 100 Silver, lead, zinc the Werlauer Gewrek­ copper. and pyrites schaft at Prinzenstein, St. Goar on the Rhine 139 Societe anonyme des 100 Silver, lead and Mines de Guerrouma blende at Palestro, Algiers 140 Kodja and Ary Maghara 100 Silver, lead and Societe des Usines du blende Laurium; Balia, Asia Minor 141 Societe des Usines du Iron Ore Laurium Ergastiria 142 San Miguel, Linares, Spain 50 Silver, lead, zinc 143 do. do. 50 Do. 144 Schisshytte, Molmbo, Swe­ 200 Do. den DESCRIPTION

OF A.

New Coal Washing Plant at Ferdinand Grube" Kattowitz, in Upper Silesia.

GREAT deal has been said and written on the subject of coal washing, but it will always be of great interest to coal miners II] and others to have their attention drawn to special and important instances. IT is with this object in view that a description of the new coal washing plant erected at the collieries of Messrs. Thiele-Winkler & Co., at Kattowitz, in Upper Silesia, is offered to the reader. T HIS large plant was erected by C. Llihrig in the year 1887-88 on the site appointed by Messrs. Von Thiele-Winkler & Co. THE plant is constructed to do the following work:-

DRY separation of the total output of the mine.

S EPARATION of the lump coal.

SEPARATION and washing of' the dross or slack into nut and pea coal in order to obtain as clean a product as possible, breakage of the Jump and loss of coal being kept as low as possible.

EASY separation and transport of the refuse and sludge.

recovery of bye-products; in this case iron

THE ' pyrites.

A LSO, arrangements for storing large quantities of the washed products had to be made, and special arrangements for easy loading.

M ANDAL labour was to. be economized to as large an extent as possible.

OTHER difficult conditions were, however, made by

. the Company, namely:- . THE Ferdinand Pits produce a hard and easily breakable, non-coking, dry coal, of rather good heating quality, intergrown and mixed with shale and slate to a large extent. The average percentage of ash is 25 per cent. THE coal was formerly separated by dry process viz., by hand picking and screening; bad shaley coal, often 10 per cent of the total output, was simply separated out, giving a product of low value, whereas the fine dirty coal was almost value­ less and could only be used by the colliery people

themselves. T HE object of the plant was essentially to increase the value of the lump and nut coal and render the fine coal saleable.

BESIDES this it was made conditional that the washed coal should on the average contain 4 per cent. of the ash at the most. T HAT the washed-out refuse should contain not more than 3 per cent. of coal.

capacity of the plant was to be 1,500 to 1,750

r[HE. tons per day of 10 hours, but as a fact, the plant was capable of treating 400 to 500 tons of coal per day extra, from the large quantities stored up around the colliery. 30 FINALLY, the whole plant was to be completed and started to work within 7 months from the day of first cutting the so.d. These various conditions were carried out and confirmed to the perfect satis­ faction of all parties concerned.

DESCRIPTION.

1. SECTION.-DRY SEPARATION.

THE total output of the Gruschka Pit, at Ferdinand Colliery, is passed along a covered way (which effectually keeps off the weather,) in hutches carrying aboutrc cwt. each, into the dry separation building. The coal is then passed through two self-acting tumblers on to two patent reciprocating bar screens, from which the lump coal, that is, coal over 5 inches, goes on to picking and loading tables-these latter are so arranged as to combine a picking table and loading band; the "throughs" from the recipro­ cating bar screens fall on to shaking screens of 3Yz inch mesh, and are separated into sizes of 3Yz inches to 5 inches, and smalls from 3 Yz inches downward,

THE lump coal passes on to three loading and picking tables, whilst the smalls (under 3Yz inches) fall into bunkers, each of 100 ton capacity: 31

THE lump coal is separated from the larger pieces of slates and mixed coal by hand on the picking and loading table. The picked coal is then loaded into railway trucks, or raised into hutches running on a platform 15 feet above the metals for immediate use or storage respectively.

THE clean slates, separated from the coal on the picking tables, are thrown into shoots, and are taken away in small hutches on to the shale tip, whilst the mixed coal, also separated from the clean lump, is thrown into shoots which fe.ed two powerful stone-breakers, the broken coal is elevated and dropped into the dross or slack bunker.

AT this stage the wet separation process begins, that is, after proper dry sizing of the coal by revolving screens.

BOTH the dry and wet separation works have special driving engines so as to allow of their independent . working.

II. SECTION.-THE COAL WASHER.

THE washing plant consists of two distinct systems, at least, so far as the nut and peas washing por- tion is concerned, and can be worked independently. The fine coal washing portion is one system. OWING to the large dimensions the machinery would have received, because of so large a working capacity, this plan was resorted to, it also enables repairs being undertaken without having to stop the work of the whole plant. THE slack or dross from the bunkers in the dry separation is raised by means of elevators to a height of nearly 3'5 feet to a worm which carries it into revolving screens. These screens have 3 muffles or mantles made of steel, the inside one has a mesh of 2 Yz inches, the second one I J8 inches, and the outside one Yz inch, so that three kinds of nut and pea coal are made, whilst all the coal under Yz inch passes through the outer screen direct into the fine coal washing section of the plant.

T HE different sizes of nut and pea coal pass down spouts into separate nut and pea coal washers.

. T HIS arrangement of revolving screen has the ad- vantage of rapidly separating coal into several, sizes without causing unnecessary breakages.

IT is evident that there will be dirty coal, that is, coal intergrown with shale, mixed with the rest of 33 the dross from the sizes of Yz inch to 2 Yz inches, this intergrown coal genera11y decreases the value of the washed product, as it cannot we11 be separated from the other without losing the coal adhering to the shale, and often such cocl is much too valuable to a110w it to pass away with the refuse. FOR the treatment of the coal, Liihrig has invented a special washing and dressing process. THESE nuts washers, built and used by Liihrig, and constructed according to his system, do not make only two products, viz, washed coal and refuse, but three, viz., washed coal, mixed product and refuse; this is a matter of very great importance, and has proved a great success.

THE clean nut and pea coal is carried away by the stream of water to the drainers, and from these passes Jnto hoppers; whilst the washed out refuse is carried away into the refuse pit.

" THE "mixed product, in this case 2 per cent. of the total output, is carried by a stream of water to a special elevator, which rises it to a stonebreaker placed on the same floor as the revolving screens. After breaking, the coal goes through a sma11 revolv­ ing screen, and is sized into two sizes of peas and fine coal, the former is rewashed on special washers; 34

the refuse from these washers likewise goes to the refuse pit, whilst the washed coal passes to drainers, where it is again sized into two different sizes and passed into hoppers. THE "mixed product" from all the washers, so treated, although not absolutely clean, makes quite a fair saleable nut and pea coal. It was inter­ stratified ;vith from 25 to 30 per cent. of shale and slates, 20 per cent. of which has been got rid of. Arrangements are made to either mix it with the clean nut, or use it for local or steam purposes. ESPECIAL stress is laid upon the fact that the manual labour is not increased at all, as the two extra washers are attended to by' the man looking after the other washers.

ONE draining drum is supplied to each washer, and whilst the smaller sizes pass through draining drums having two mantles with different meshes.(thus enabling the coal to be sized again), the larger nut coal is drained through drums with only one mantle.

T HE washed nut coal can be loaded and taken away in small trucks on a platform on the same level as the heapstead, the capacity of the washed nut coal hoppers is 220 tons, which are so arranged that one day's work can be easily stored up in them. 35 THE fine coal under 76 inch, together with the wash water from the various apparatuses, passes into a system of graders, consisting of five divisions, the fine coal is here graded according to relative weight,

and each division feeds one of the five fine coal washers. THESE five fine coal washers are built on the Liihrig System and are especially constructed for washing fine coal under 76 inch. One man only is necessary to attend to these washers which have five sub-divisions

each, making in all 25 ordinary sized washers. THE results obtained from these fine coal washers are so excellent that the neighbouring zinc works take all the fine coal washed at the plant, and prefer it to any other to be had in Upper Silesia.

T HE fine washed coal is led by a stream of water into a revolving draining screen, which sizes off the larger coal, this is raised by an elevator into the fine coal hopper, whilst the finest, together with the Water, passes into a long sludge or settling pit, in which Liihrig's sludge recovering apparatus works. THIS apparatus, which extends along the whole length of the settling pit, works very slowly and with the flow of the water, scraping and

If COllecting the very finest sludge or "schlamm, 36 which settles at the bottom of the pit, into another at a lower level, and an elevator with perforated buckets raises the fine sludge from this pit into hoppers placed next to the fine coal hoppers pre­ viously referred to, the sludge can then either be mixed with the fine coal, or it can be used by itself for steam purposes. THE water drains off at the further end of the set­ tling pit and passes into the clear water tank, from which it is raised by means of centrifugal pumps in order to be used again for washing. E SPECIAL arrangements are made at this plant for . the recovery of bye products, in this case iron pyrites. The whole of the refuse of the fine coal wash­ ers and passing main refuse shoot is led into a special grader or spitzkasten, and from this into two washers constructed for the treatment of ores. The pyrites is washed and concentrated to about 40-45 per cent., of which about I Yz tons are made when working up 1,500 tons of coal per day (ten hours). T HE necessary water is circulated by two centri- fugal pumps worked from the engine driving the plant, the piping and water arrangements are arranged in a most perfect manner. Special heating arrange­ ments are also made on account of the severe weather. 37 THE whole plant, separation. works and washer, including loading arrangements, railway station, transfer tables, wagon shops, etc., are lighted by electricity. The dynamo and engine for working the washer are placed in the same building, and one man attends to both.

1-IOW well the heating and other arrangements have been attended to is proved by the fact that during the winter of 1887-8 there was no interruption in the work of the plant, even with the thermometer as low as 25° R.

T HE cost of working (exclusive of steam and depreciation of plant) is exceedingly low, namely, three-tenths oj a penny per ton only. I F the question should be put whether the conditions of the contract have been fulfilled, one can only

answer with an affirmative.

FIRSTLY-The whole arrangement of the plant, considering the property of the coal and other difficulties, is excellent. SECONDLY-The official tests confirmed the ash in the washed coal to be only 4 per cent., and the washed-out refuse to contain less than 2 per cent. of coal. T HE loss of coal in the slimes is brought down to a minimum by the perfect working of the sludge recovery apparatus.

THIRDLY-The capacity of the plant, 1,500 tons per day of 10 hours, has often been exceeded. Whilst I was there, the plant was working up an extra 400 tons from the storage, besides the usual 1,500 tons per day. TAKING into account the good arrangements, the good construction of the machinery, the solidity and good workmanship shown in the buildings, the capacity and easy access to every part, besides the exception1y low cost of working, one must come to the conclusion that this is a model coal washing plant in every respect. SOME OF THE ADVANTAGES

OF

LUHRIG'S PROCESS.

importance of separating coal from the incombustible impurities which are always found with it when brought out from the OREmine, may be made clear if the effects resulting from the use of impure coal in metallurgical operations be shortly considered. It is evident that the loss entailed by neglecting to remove the impurities in coal used for such purposes, as also, for steam generating, must be of great magnitude.

IT may, therefore, be we�l to estim�te t�e loss.d.ue �o III a given percentage of incombustible impurities fuel used for smelting iron in 2. blast furnace, and also to consider the same question with reference to the generation of steam. THE incombustible matter present in coal generally consists of silicate of alumina and oxide of iron. In blast furnaces, the oxide of iron is reduced; but when present in fuel used for steam, it forms into clinkers on the bars of the furnace grate, resulting in great loss. COAL ashes often contain about 90 per cent. of sili­ the ;.. cate of alumina; proportion of silica to alumina is generally � to 2. The latter proportion generally exists in coal with a high percentage of ash. T HIS silicate. is almost infusible, and in order to flux it for good working of the furnace it re­ quires an addition of lime.

I N blast furnaces on Bessemer iron, the slags are generally of the following composition : Lime 47 Silicia 38

Alumina 15 THE proportion between alumina and lime is about I to 3; but if lime be added in the same proportion to the alumina of the ashes of the fuel, the proportion of the bases to the silica will be much greater than in the Bessemer slag. However, to prevent an exaggerated estimate of loss, the lime (in the following calculation) will be only added in 41 sufficient quantity to make the ashes of the fuel as basic as- the remainder of the slag produced in the furnace.

LET it be assumed that 22 cwt. of coke, containing: Carbon, 92 per cent. Ash, 5"" Moisture, 3" " will produce I ton of Bessemer iron.

THE following will show, with t�is data, what amount of coke will be required when the coke contains:- Carbon, 82 per cent. Ash, I5" "

" " Moisture, 3

The principal elements of the ash being:- Silica, 49 per cent.

" " Alumina, 25 Lime, &c., 8" " 22 cwt. of coke, with 92 per cent. of carbon, give 20.24 cwt. of carbon per I ton of iron.

AGAIN, 20.24 cwt. of carbon represents 24· 7 cwt. 0.1 coke when there is 82 per cent. 0.1 carbon, that is, wz'th I5per cent. 0.1 ash. THE 10 per cent. of extra ash in the dirtier coke= 2.5 cwt., consisting of 1.23 cwt., silica, 0.82 cwt. bases, 0.45 cwt. oxide of iron.

THE bases take up 0.5 cwt. of silica, leaving 0·73 cwt. to be fluxed by adding lime to the extent of I. 2 cwt., which is equal to 2.2 cwt. of limestone.

THE total slag due to the extra 10 per cent. of ash in the coke will therefore be 3.7 cwt., consisting of 2.5 cwt. of ashes + I. 2 cwt. of lime.

Cwt.vunits . T HE fusion of 3· 7 cwt. of slag requires, - according to Bell, 3.7 x 550 - = 2,035 To expel the carbonic acid from 2.2 cwt. of limestone requires 2.2 X 370 814 To decompose 0.264 cwt. of carbonic acid

of the limestone requires 0.264, x 3,200 = 845

Total cwt.· heat-units 3,694

TAKING 4,400 as the number of units develc:ped by I cwt. of carbon in the blast furnace, the above will represent- 3,694 --= 0.84 cwt. of carbon. 4,400 43 THE carbon, therefore, in the inferior coke must be 20.24 + 0.84 = 2I. 08 instead of 20.24 cwt.

CO�SEQUENTLY the coke required, with IS per cent. of ash, will be 82 : 100:: 2 I. 08 : 25.7 cwt., or 3.7 cwt. coke for, every I ton of iron produced, more than coke with only 5 per cent. of ash; or about I7 per cent. coke extra.

TO this loss should be added the cost of 2 U cwt. of limestone, which would itself more than cover the cost of washing.

IT is evident therefore that a great saving can be effected by washing coal to be used for metal­ lurgical purposes.

I N the,' process of washing in question, nothing essential to coking is lost, this is certainly, often the case with single machines at present operated at. collieries, but all loss of bituminous matter, or of pure coal in any form, has been brought to a mini­ mum by this process.

THE eminent Dr. C. Otto, inventor of the well­ known Otto coke oven, on being asked his opinion of the statement that several specialists held 44 it to be better and more economical to flux the superfluous ash, i. e., shale and slates, in the blast furnace on this account, stated:-

"I have during my long experience with Luhrig's "process of ·zoashi:zg, never found thd the washed "coal is deprived of anything essential to the pro­ "duction of good coke for blast furnace purposes,

" on the contrary, I have found that coke made from "a coking coal previously washed by this process is "always firmer, harder, and more suitable for "metallurgical purposes, than un1f.Jashed coal, aud "I consider it always exceedingly wasteful to

"" attempt to flux tlte ash contained in the coke when "it can be previously ·separated from the coal by

" '� this process.

A MONG other losses through the use of impure fuel that of transport may be reckoned: this bears a direct proportion to the percentage of im­ purities carried, requiring extra rolling stock.

GAIN, the cost of manufacture of coke from dirty .J.A. coal is greatly increased.

SAY the coke produced contains 10 per cent. of ash, which could all be removed by a good process of washing, it is necessary to supply sufficient coking 45

plant to allow the tenth part of the whole to be unpro­ ductive, as far as coke is concerned.

THUS, if 90 ovens will produce a desired quantity with washed coal, the additional 10 ovens neces­ saryin the assumed case at, say, £100 per oven, would represent quite a substantial outlay, which could certainly have been more profitably spent in good coal washing machinery; moreover all labour cost in the coking department has been increased.

S far as the generation of steam in boilers is con- A. cerned, the principal loss to the ash in the fuel is that arising from the difficulty of effecting economical combustion, owing to the ash forming a clinker on the bars of the grate.

THE following from "Percy's Metallurgy" describes the action of the ash in boiler furnaces. -" When the ashes sinter together or melt they form a more or less virtrified mass termed clinker, which may accu­ mulate upon the bars, so as greatly to impede the passage of air between them and, as a consequence, lower the temperature of the furnace. Moreover, When the bars are covered with a firmly adherent bed of clinker, and are no longer cooled by a continuous current of cold air, they may soon become heated and destroyed by oxidation. TO compensate for these losses, an extra amount of fuel must be provided, the cost of which, together with its carriage and the disposal of ash, are items

which should make it evident that the shale-i. e., ash-should be separated as completely as possible from the coal by a process of washing.

THE perfecting of such a process has been the exclusive work of Mr. C. Ltihrig during the last 25 years, and he has been eminently successful in every respect. REPORT

ON LUHRIG'S SYSTEM OF COAL WASHiNG,

BY

PROFESSOR C. KREISCHER

(R

Printed by permission of the Minister of Mines, Saxony.

" preparation of minerals, .forrnerly ex- " to has � � elusively applied ores, latterly " been adapted to coal in this country. 1IIIr" In the first half of this century coal "underwent no other process than a little hand­ {, picking. the effect of which was to remove only the

" larger pieces of dirt or shale. "AT that period washing was not required, because " the supply of large coal was sufficient for the

" entire demand, and yielded to coal owners an ade­

,. quate profit. Small coal being useless and of no " value was either left in the pit or thrown to waste.

" Even hand-picking was only carried on at these "collieries where. the coal was more than usually " dirty. In the case of clean coal, what separation

, , there was took place under ground. "AT that time, when the demand was limited, and " prices were sti11low, coal owners only cared

" to work 'the clean portions of their seams, and left " the dirt together with the small, in the pit.

"A S the demand increased, wages rose in proportion, " and the requirements of the various indus­ "trie�, especially Ironworks, in reference to the "heating power and purity of their fuel, increased "also, and coal owners began to feel the necessity

" of bringing into a marketable condition coal which " had hitherto been worthless.

" I T was principally through the development of "coking operations, that the attention of iron­

" masters was called to the necessity of increased

" and at the same time purity of fuel, increased work- . "ing expenses compelled coal owners to use up their " small and inferior qualities as much as possible.

" I N this emergency coking came to their aid, for it " was soon recognized that small and fine mater­ "ial is more suited for making a regular quality of 49

" coke than the large coal, which at first was ex­

" elusively employed for this purpose.

" COLLIERIES working seams yielding a pure " coal and not much small, were effected com­

" paratively little by this new state of things, whereas "those less favorably situated had the greatest

" difficulty in working at a profit.

" I T was these latter districts which afforded the " most favorable ground for the development "of cleansing processes, and it was here where the

" most perfect,washing machines were erected.

" I N the first instance the separation of the larger "coal into classes according to size was sue­ " cessfully attempted, the results obtained having "been anticipated in the subdivision of ores by '" screening machinery, and in the working off of the "resulting products in jiggers.

" DIFFICULTIES were the less apparent with the "large coal, because the specific gravity of "the two substances to be separated-about 1. 3 for

'" coal and 2.3 for impurities-admitted of compara­ "tivelyeasy sub-division.

", BUT differently constructed jiggers were found "to be necessary, because the large quantity of

" material to be washed required a continuous out- 50

'flow, and manual labour was not sufficient for that

" purpose.

" IT was much more difficult to obtain a successful "result at the first attempts that were made to " wash small coal varying in size from }'8 inch to o.

,� THE apparatus at that ·jme in use for the separa- "tion of ores of similar dimensions could only "be partially employed. For the most part coal " washing systems were, therefore, confined to the " three first operations, i. e. :- "I. The sub-division of the nut coal by means

" of screens,

" II. Washing the various classes in washers or " jigs, "III. The cleansing of the fine dust coal in " troughs,

and colliery proprietors were satisfied by diminish­ "ing the contents of ash in the small coal to the

" extent possible by means of trough washing. At

" the top of the trough, the pieces of shale of 3i and

" under will deposit, no particles of coal of an equal' " weight being mixed with them, taking into account " the specific gravity between coal and shale already "referred to. It is only when the coal is mixed with " shale in dimensions of under 2\ inch, that the coal " itself deposits in the course of the flow. 51 "I T is, therefore, clear that clean coal cannot be "produced unless the physical constitution of the "shale be so favourable that it forms very fine par­ "ticles, or shale. in the form of powder does not exist "at all. "I N this case the fine coal will be much cleaner, "inasmuch as it is not mixed with particles of "shale of equal specified gravity, or if so, in very "small proportions. "I N this category of coal washing may be reckoned "that of Rexroth, Sievers and others. At Rexroth "the fine coal was entirely withdrawn from the wash­ "ing process, and was mixed unwashed with the "large; Whereas at Sievers the difficulty was to a "slight extent remedied by means of a trough appa­ "ratus, in which the shale was partially deposited, "but the result was not satisfactory.

" ALL these washing processes suffer from this "defect, that the fine coal could not be properly "washed at all, and the entire washed coal contained "too great a precentage of ash for profitable use. It "was in this direction therefore that improvements

; 'were to be sough t after, and they were first thoroughly ;'and completely obtained by Mr. C. ,Liihrig, in his ; 'system of coal washing, now so well known in "many districts. He .employed Rittinger graders, �'which he specially adapted to the cleaning of small � 'coal, and the Harz jigger, well known in the "preparation of ores.

"WHILST the small coalis gradedaccording to the "size and weight, the separation of the shale

� 'from the coal takes place in the jigger, thus we find '''in Liihrig's arrangements the first complete and satis­

., 'factory system of coal 'lClashing .

. , 'M R. C. LUHRIG, having made his first attempts "on silver and lead ores in 1863, turned his "attention in 1867 to the washing of coal by adding �'his'special washer to the coal washing plant then in "operation at the Gllickhilf Colliery, Hermsdorf, near "Waldenburg, in Si1e�ia; the result was a complete "success, as the Author was able to observe in the "course of a Government Inspection, in the year 1879.

"AFTERWARDS Mr. C. Llihrigerected. washing "machines in Russia, Austria and Germany, "principally at collieries. and by dint of great care "and minute observation, made such improvements "as to enable him to guarantee, not only the quantity "that could be 'Zvashed, but also a definite result in "quality as regards purity. His system of washing is "without doubt a great success, and has been most "extensiv�ly employed throughout Europe." 53 THE learned professor proceeds to state that the extraordinary extension of Ltihrig's washing machines justifies a more detailed description of the improvements made, but the reader will not be troubled with this, inasmuch as within the last six years, since the time when his report was written, the further improvements wnich Mr. Ltihrig has been able to introduce render his detailed description of the machinery almost obselete, although of interest.

D ESTIMATES OF PROFITS.

A.-Saving in the Pit.

LUHRIG'S experience has proved that in most cases, the whole of the workable

seams of a mine can be raised without ImR.previous separation under ground, and that. the output of a mine is therefore generally largely increased; in the present case (a Scotch colliery), the difference expressed in money would be from two to four pence per ton of coal, and as the work of each collier could on this account be increased by half a ton per day of 10 hours, the saving in these pits, where 300 men are employed, would * be 300 x 9d. x 300 = £3,375 per annum.

B. -Saving in usiug up Mixed Coal. AT the colliery referred to, 18 tons of mixed coal are daily thrown upon the shale tip or waste (being 5,400 tons per annum). Marketable nut, pea and fine

*3 tons per day per man. 55 coal can be produced from this coal, the latter could be well used for coking purposes. After' deducting 18 per cent. of shale, slates and brasses or pyrites, which are separated out by the Liihrig process, 4,428 tons would remain, of which three classes of coal could be made, viz:-

. 33t per cent. = 1,476 tons of nut coal, at 4/4 £319 " 33t = 1,476 "pea"" 3/- = £221 " " fine" "2/10= £208

Saving per annum

C. -Saving z'n Cokz'ng. BY washing, the yield of coke in this c�se was in- creased by 6 per cent., ISO tons of coal yielding 56 per cent. of coke against 50 per cent.-9 tons of

coke per day increase; or 9 x 300 = 2,700 tons per annum. Price of coke = 9/- =9/-X 2,7oo":_£1,215.

D.-Increase of Lump Coal. BY dint of careful handling and good loading ar- rangements, built at this plant by C. Liihrig, the yield of lump coal has been increased by 6 per cent., this, with an output of 1,000 tons, of which 50 per cent. is lump coal, gives 500 x 6 per cent. = 30 tons

per day increase, which at 8s. per ton. is 30 x 8/- =

x = annum 240 300 £3,600 per ..

* 1888. E.-r-.f?ecovery of Bye Products (Pyrites). TWO t�ns of pyrites, with 40 per cent. of sulphur are recovered per day, and can be sold at 25S. per ton; or £2 lOS. per day = £750 per annum. Total Savings. A. -Saving in the pits

B.-Saving in wasted coal -

C.-Saving in coking 1,215

D.-Saving in lump coal - 3,600 E.-Saving in bye products

99,698 saved per annum, without taking into account the increased value of nut, pea, pearl and fine coalpro­ duced by the plant. The price of th� plant referred to was £10,000 complete with buildings and engines. Total savings per annum Depreciation of plant 10 per cent. - £1,000 Repairs 20 Labour, steam and oillabour, at s d. per ton inclusive 2,000 Interest on capital, 5 per cent. 500

Profit £6, I 78 ESTIMATE OF PROFITS AT

HEINITZ COLLIERY,

SILESIA.

LARGE .. coal washing and coking plant

, was erected at this mine by C. Liihrig on his system. This plant is, in the opinion 11 of all Upper Silesian mining experts, practically perfect, and has enabled the Reinitz col­ lieries to compete favorably with the best Silesian coal and coke.

ACCORDING to extensive tests made at Reden­ hiitte, the dross or slack was proved to contain 22 to 24 per cent. of ash, whilst the washed product did not exceed 5 to 6 per cent.

TRE mechanical appliances and general arrange­ ments of the washing plant are such, that the repairs do not exceed £I2 to £I5 per annum. tests the cost of

C. AREF�L .have prove� �ork�ng, that IS, washing, separating and loading into trucks, not to exceed one half-penny per tan of aU coal treated.

LABORATORY tests and practical tests have shown that the coal from the Reinitz Collieries will yield a very good coke when mixed with 30 to 35 per cent. of coking coal; the Reinitz coal, that is, the coal from Bismark and Mathilda pits, is known as a non-coking coal.

TRE following calculations are based upon the fact that the fine coal or slack was formerly quite useless for coking purposes i-e- The coke ovens also built by Mr. Llihrig use 160 tons of coal per day, of which 30 per cent., or 48 tons, is fine coal. With a daily output of 750 tons, the percentage of fine coal is 8 per cent. or 60 tons; after deducting 48 tons for coking, there remain 12 tons which _are used for boiler firing. The fine coal formerly useless for coking is taken at 2S. per ten, which brings the colliery a profit of

* = '1.4$. per ton, or I.4s. x 48 67. 2S., or £3 7s .

. per.day. 59

T RE price of coke would then be as follows i-c-

One ton of best Upper Silesian coking coal costs the Reinitz colliery 5S. per ton. The cost therefore, with an addition of 30 per cent. of the Heinitz mines washed fine coal would be

(1.°% x 5s.) x (30% x 2S.) =4S. per ton. 100

With a yield of 62 per cent., 1.4 tons of coal would be needed to everyone ton of coke made, or

1.4 x 4s. = 5s. 6d. per ton.

The cost of labour can be taken at 6d. per ton, so that the total cost of production is 6s. per one ton, loaded into wagons.

The sale price of coke is lOS. per ton, this leaves

. a margin of 4S. per ton, or with a daily product- tion of 160 x 0.62=88 tons, or 88 x 4s. = 12S. ---;0- £ 17 per day, or £5,280 per annum. DR. KOSMAN, government mining expert, has re- ported fully on this plant, and says :-" The "coal washing plant has greatly exceeded the results "guaranteed, and can be truly said to be the back­ "bone of the Reinitz Colliery." APPENDIX I.

TESTS MADE AT BRDcKENBERG

PIT No. II., near ZWICKAU.

F-==::;;jHE dross at Brilckenberg Pit No. II, con, tains 25 per cent. of ash, whilst the fixed ash of the ordinary coal averages 2. 3 per cent. ; by washing, the percentage of ash is reduced to 5 to 6, so that 19 to 20 per cent of slates and dirt are got rid of, whilst 2.7 to 3.7 per cent. of slates and dirt are retained in the coal.

A SPECIAL experimental and careful hand-wash­ ing test gave only 0.1 per cent. less percentage of ash, proving that the washing is as perfect as it is practical to make it. THE following figures were taken in August, September, October and November, 1875, and BrUckenberg Pit No. II., Zwickau:- 61

LUMP COAL. MIXED COAL SHALY COAL. (DROSS).

--� I No. Percent- No. Percent- No. Percent- Total of age of of age of \ of age of No. of Month. Hutches. Output. Hutches. Output. ' Hutches. Output. Hutches.

I --_ --- --_ --_

1,205 5·99 18,618 92.54 295 1.47 20,118 August. 1,252 6.20 18,725 92.68 227 1.12 20,204 Sept. I Oct. 1,562 6·77 21,377 92.59 149 0.64 23,088 1,491 7.29 18,827 92•08 129 0.63 20,447 Nov. IiI _------5,510 �\ 770547192.48 800 0·93 83,857 rr HE cost of treating the lump coal for the four months was 1,708.63 marks.

" Or per hutch 0.091

" Cost of treating mixed coal was 1,670.99

" Or per hutch - 0.088

Cost of treating the shaly coal was 1,737·53

" Or per hutch 0.0920

This gives an average cost for the four months, of

0.092 marks per hutch of 11 cwt., or 0.1668 marks per 1 ton, or about 1 Yz d. per 1 ton of coal; this is exceptionally high, owing to the manual labour em- ployed in the emptying of settling ponds which are now no longer required.

LEAVING out of account the labour employed at the loading hoppers as really not necessary for the treatment of the coal, the cost of treatment would �e I. 2 pence per 1 ton.

THE exact cost of a plant, such as at Brtickenberg, could not very well be estimated, as the ma­ chinery was built into buildings formerly used for another purpose.

MR. LUHRIG, however, estimates the cost of a 500 ton plant at 60-70,000 marks in Saxony.

TAKING 62,000 marks as the cost of this plant, and 5 per cent. interest on this capital, 10 per cent. depreciation of plant, 5 per cent. interest on outlay, that is 12,400 marks per annum, then the daily expenses would be 42.70 marks. This would bring the cost of working to 0,052 marks per one ton, to which manual labour would have to be added.

THE following is a Table showing the quantity of different classes of coal produced by the washer during August, September, October and November:- NUMBER OF HUTCHES.

Lump Lump Nut Nut Middle Month. Beans. Peas. Coking TOTAL. I. II. I. I II. I I. Coal. Sludge. Product.

------�

- - August 3,032 1,005 3,941 3,235 2,606 1,400 I 1,719 1,746 219 18,903 - 886 September 3,330 3,762 3,102 2,7°8 1,140 1.539 J ,616 616 18,699 0\ CN

October - - 3,997 820 4,383 3,561 2,987 2,018 1,539 1,818 839 21,462

November - . 3,627 717 3,657 3,018 2,4Q5 1,378 1,196 1,172 606 17,770

------�-- ---

TOTAL - - 13,986 3,428 15,743 12,916 10,7°6 5,936 5,993 6,352 2,280 76,834

------

Per Cent. 18.259 4-462 20.489 16.810 13·934 7.718 7·799 7.616 2.967 100.054 I T must be borne in mind that although the washing plant at Brlickenberg Pit No. II, is one of the largest in the Zwickau district built on Llihrig's system, it does not contain all of Llihrig's latest im­ provements, for this reason, the cost of working, &c., are higher than those recently erected by Mr. Llihrig.

A�OTHER interesting test was made by Professor Kreicher in a Llihrig plant at Forst Pit, near Oberkohndorf. The percentage of ash in the dross was 22 to 24 per cent. Mr. Luhrig guaranteed the per­ centage of ash in the washed coal not to exceed six per cent., and the capacity of the plant to be ISO tons per day of 10 hours. The quantity worked up during the last quarter of the year 1875, was 167 tons per 10 hours. The highest quantity washed through was 188 tons in 10 hours on the 17th November, 1875.

THE ,various guarantees were confirmed by the Government Laboratory, at Marienhtitte, and gave the following results:-

1. April 22lld, 1875, shortly after starting of the plant- Coking coal 6.75 per cent. ash 2. May 1St, 1879--

Coal from nuts washer I. - 6.758 per cent. ash

" " " " " ". " II. - 7.500

" " " " "" " III. - 7.000

" " " " " " " IV. - 5· 750

Fille Coal TVashers.

Coal from fine coal washers - 6. per cent. ash

" " " " " 5.8 " "

Refuse.

From nuts washers I. and II.

(incombustible matter) 85 per cent. From nuts washers III. and IV. (incombustible matter) 88 " From fine coal washers (incom­ " bustible matter) 81 From fine coal washers (incom­ bustible matter) " APPENDIX II.

TABLE

OF

RESULTS OF DAILY ANALYSES FOR ASH IN COKE,

MADE AT

UNITED MARIA-ANNE AND STEINBANK COLLIERIES, BOCHUM, March, I8J'o.

Per Cent. Per Cent. Per Cent.

21 - I 5.027 II 5.020 4·945 2 12 - I 22 4·733 4.762 4· 775 3 4.625 13 - 4. 121 23 4.900

- 4 - 4· 837 14 - 4.983 24 4.936

- 5 4.099 15 4.703 25 4· 747 II - 6 4.161 16 4.672 27 4.823

- 7 4·335 17 4.676 30 4.989 8 4.602 18 5.082 II 31 - 4.691 9 5.029 19 - 4.903

- 10 - 5.031 20 4.645 II _46'i?� 47.580 IiII 38.764

Total - 132.8 S 2 per cent. for 28 days.

Or a Dally Average of - - - - 4· 74S per cent. Daily Average of Ash. Daily Average of Ash . PerCent. . PerCent. February 5.046 October - 4.764 January - 4.867 September - 4· 575 December 4.850 August - 4.720 - - ul - November 4.748 J Y . 4· 669

Previous to washing, the coke contained 10 per cent. of ash, it now fetches 4S. per ton more than before (March 1880). Capacity of Plant, 1,000 tons per 10 hours.

Proprietors :-

THE BbcHUM MINING AND CAST STEEL MANUFACTURING COMPANY, Bochum, Westphalia.

""'�'j" COAL WASHING FOR COKE

MAKING.

[From "The Engineer," February 27th, 1891.J

IRONMASTERS and colliery owners are now more than ever driven to consider the means of im­ proving the quality and yield of coke, and of utilising inferior and dirty seams of coal for the manufacture of coke or briquette. At the present time there are many furnaces standing idle owing to the scarcity and high price of coke, which might otherwise be producing iron. Those colliery owners therefore who have inferior seams would do well to look into the matter with a view to equipment, with overbank ar­ rangements which will enable them to work those seams profitably before their better seams are worked out, and produce a coke with less sulphur and ash and with better physical properties than the neighbor­ ing brands not similarly treated. Many of these in­ ferior or dirty seams, when suitably manipulated, make a better coke than the cleaner seams at present being worked, and these seams are in most cases being left unworked owing to the above ground ar- rangement being inadequate'to cope with them. It

- is in such cases that the question of efficient applian­ ces for cleaning all the qualities of coal, especially the pit slack and smudge, becomes of vital impor­ tance to colliery owners who desire to derive the greatest benefit from their underground and un­ developed resources. About a year ago we called attention to a new coal-washing plant, which was being erected for the Maryport Hematite Iron and Steel Company, at its Ellqnbro' Colliery. The plan adopted was the pro­ cess introduced into this country by' Messrs. Simon and Luhrig, which firm has since merged into the Luhrig Coal and Ore Dressing Appliances, Limited, Westminister. The plant is divided into two distinct portions. The first, the dry separation, where all the coal above the size of nuts is treated, and the other the washery proper, in which everything from the size of nuts to smudge is operated upon, and each portion is independent of the other, as a storage for a large quantity of small coal is supplied, enab-· ling the washery portion to be stopped when re­ quired for hours, without interfering with the other portion of the drawing of coals from the pit. The tubs on leaving the cars travel along a platform and

pass on to the tumblers, there depositing the con­ tents on jigger screens, where the large coal gravi- 70

tates on to the picking bands, and the small coal drops into a large storage bin underneath, which is in communication with the washery. The large coal is hand-picked on the travelling bands, and the dirty pieces picked out are thrown into a box, which is in connection with a small crusher below by means of shoots, and there the lumps are crushed very small, detaching the shale .and brassy pieces from the ad­ hering coal, and these fragments are then elevated into the storage bin for small coal before mentioned. By means of a large and powerful elevator travel­ ing at a slow speed, the small coal mixture to be washed is taken to the top floor of the building and passes into a large sizing drum, where it is eorted into four different sizes, varying from large nuts to smudge, preparatory to undergoing the jigging pro­ cess. Each different size of coal is fed into its re­ spective jigging machine, whereby nuts, beans, peas, and the finest smudge are jigged separately, and the various sizes may either be passed over draining riddles and sold as they are, or passed through the crushing arrangements and used for making coke, in",which case they are elevated up into large storage bins along with the ordinary coking coal. The re­ covery of sludge is carried out by the method intro­ duced into this country by the Luhrig Appliance C��pany. Settling tanks are entirely obviated, the 71-

water suitably clarified, i. e., in such a way that not one drop of water need be allowed to run a\Vay. In the Maryport coking coal, and in most of the West Cumberland coking seams, there is found a quantity of a kind of cannel or gas coal, containing

. a very high percentage of fixed ash, and a specific gravity very little heavier than that of the coking coal. It was therefore necessary, owing to the amount of ash, to keep this coal out of the coking coal, and yet being a saleable product it was de. sirable to pass it out by itself freed from refuse or impurities. This has been most successfully and advantageously, done by the Luhrig Company as follows:-The coal in its mixed state is fed into the jiggers already mentioned. These jiggers are so regulated in working that only the lighter class of coal will pass over the sills of the jiggers. The heavier class of coal, together with the impurities, is drawn off by means of the outlet usually serving for the outlet of impurities. This material is then sized and delivered into a second set of jiggers for fUrther treatment. The heavy coal in the case is delivered from the latter over the draining sieves into storage hoppers for delivery into trucks, and the impurities alone are drawn off from the bottom of the jiggers. The impurities from these jiggers then, pass down to another set of small jiggers where the 72 pyrites contained are washed out and concentrated, and after that the refuse is taken up to hoppers to go to the waste bin. This washing and re-washing system during different and specified stages of the process enables the Luhrig Company to eliminate, to the greatest possible degree, the sulphur and other ashy objectionable matter formerly contained in the coking coal which was being produced by the Mary­ port Company previously to erecting the plant in question. The arrangements of the storage and loading into

trucks of the different kinds of washed coal are of the most complete description. The washed coking coal is deposited in very large storage bins at a suitable height, thus affording facilities for com­ pletely draining the coal previously to coking, and also for charging the same into tubs for the ovens, or into trucks as required. The Maryport Company's works are now fitted up in the most modern way suitable for its requirements and it is enabled to save considerably in wages for­ merly expended in handling the coal in a less econ­ omical manner. Further, it is producing a much purer coke of a greater density than formerly, and the loss of coal in the refuse in producing this Iatter­ mentioned result is verym inute. We are informed that this loss of coal in the refuse, according to the 73

Maryport Company's tests, is only I Yz per cent. The Maryport Company has, within the last fortnight, run one of its furnaces on coke made solely at its Ellenbro' Colliery, instead of a mixture of East coast

coke and local coke as before used. We understand

that the results obtained are thoroughly satisfactory, and it has now no hesitation in running its furnaces

. altogether on this coke, with much more economical results than when using the mixture. As far as West Cumberland is concerned, great credit is therefore due to the Maryport Company for having demon­ strated that the coals from the Cumberland basin when properly treated, as by the Luhrig process, pro­

duce a coke which is found in the blast furnaces to

be of a much superior mechanical texture to that for­ merly produced, as well as being chemically purer, and that that county has all the ingredients in its own mineral wealth, if properly and intelligently treated, without applying for fuel for blast furnaces to other coke-producing centres.

NOTES

ON THE MANUFACTURE

OF

COAL BRIQUETTES.

INTRODUCTION.

of waste is in the present. day attempte� as it never was before; this arises partly, no doubt, from our lITILIZATIONprogress in scientific knowledge, which, on the one h�nd reveals to us how rigid an economist is Nature herself, and on the other shows us how we may propitiateher. Partly, also, it is the result of the growing intensity of competition in every depart­ ment of production. FOR a long time the vast quantities of small coal and coal dust which accumulate at every colliery and on every coal merchant's hands were practically wasted. If disposed of at all, it could only be at' a price which made a considerable deduction from the aggregate profits. AFTER a time, compressing machinery was in­ vented, and the otherwise useless material made up into "briquettes," and sold as compressed or patent fuel at fair prices. F SOME of this fine coal is often so dirty that even . when made into briquettes it is of no very great .value, consequently a washing or cleaning pr�cess is necessary. The process hereinbefore described fills in all requiren:ents in cost of washing, perfection of machinery and quality of its work.

THE time is possibly not far distant before every colliery will have its own coal washing and briquette making plant. NOTES ON COAL BRIQUETTES.

definition" Briquette" was formerly only applied to cakes made of peat THEmixed with water and plastic clay, then the same name applied to cakes made of caking coal without addition of binding material, whilst such cakes of coal made of semi-caking, or dry coal, 'witlz addition of tar, pitch or other binding

'< material were known by the name of Perats." THE definitions, such as "charbons agglomeres," "briquette de charbon," "patent fuel," "coal

" briquettes, "compressed fuel" and "kohlensteine," apply to compressed fuel made of coal, either by addition of tar or other binding materials, or without such addition.

manufacture of until THE briquettes has, now, been almost exclusively applied to coal, for the pur­ pose of procuring a compressed fuel from small coal: should, however, experience up to now continue to be confirmed by further tests, there will be a large field opening up for the manufacture of briquettes from ores for metallurgical purposes. 80

manufacture of has been carried on THE briquettes for a great number of years, and was first attempted by the Chinese, according to Mengel. As early as the year 1603, Hugh Plattdescribes a pro­ cess of making briquettes, by adding sawdust, peat, clay and cow-dung, with fine coal, and compressing.

of THE systematic manufacturing briquettes by means of machinery, was first introduced by E. Marsais at St. Etienne in 1832, he made blocks of compressed fuel of about 20 lbs. weight by adding coal tar. Wylam patented a process of making briquettes, with the addition of coal pitch (braisec) in England, 1843.

the methods at present used the fuel is generally IN first separated, crushed, screened, sometimes cleansed by washing, and then compressed with or without addition of binding material.

the THE process is, however, regulated by purpose for which the briquettes are to be used, and generally the following conditions are necessary in briquettes to be employed for heating purposes:-

(I) Highest possible firmness and heating power, uniform weight, convenient size, uniform dimensions and liability to produce as little dirt, dust or smell as possible. (2 ) Not to be subject to loss of heating power by storing up for considerable periods; neither must climate have any detrimental effect upon them.

(3) Must be easily inflammable and burn with a bright flame, produce little smoke and soot, must not break up in the fire,· and must leave

little ash or cinder.

I N England the chief briquette factories are in South Wales and Cardiff, and at Newcastle and Sunder­ land." There are also factories in Somersetshire, Gloucester, London and Scotland, with a total output, according to Gurlt, of 1,000,000 tons in 1884.

MOST of these briquettes are exported for locomo­ tive and steamer work in India.

ONE of the largest factories is at Cardiff, and belongs to the Crown Preserved Coal Company.

BOUT IS years ago they employed 200 men, in A. the year 1880 only 40, although turning out a much larger quantity.

THE capacity of one press per 20 hours is S6S tons of briquettes of about 22 lbs. weight. F * 82

THE Wear Fuel Works use three Yeadon's presses, and one at Newport has a capacity of nearly

100,000 tons per annum. YEADON'S press is considered to be the most prac- tical one in the market. It is of massive con­

struction, and works with a pressure of about :2 tons per square inch. It is a steam press, and works with indirect pressure from both sides and in a horizontal direction. ESTIMATE. THE machinery necessary for a plant of 50 tons capacity per day of 10 hours, would consist of:- One elevator for transporting the coal to be crushed, I coal crusher, I disintegrator for grinding 10 tons of pitch in 10 hours, I horizontal mixer, elevator for raising the mixed material from the mixer to the dry-heating apparatus, iron parts for heating furnace, I horizontal air compresser, I horizontal heating apparatus with mixers, I press complete, also shafting, coal and hot water and steam pipes complete One boiler complete, and I high pressure engine Total £r,065 ACCOkDING to Yeadon's estimate a building of about 30 feet by 30 feet would suffice, and the cost of labour per I ton of briquettes is estimated at fi ve to seven pence per ton.

THE cost of production, according to Peters, is, including depreciation of plant, interest on cap­ itallaid out, labour, pitch, fuel, and loading expenses and repairs 3S. z d. per I ton of briquettes produced. The price of pitch is taken at 40S. per ton, and 7 per cent. used.

THE following is a description of Messrs. Mowll and Messenger's machine recently invented:-

THE machine is of comparatively small size, and the briquettes made by it measure only 4! inches long by 2! inches wide and 2i inches deep, and weigh I! lb. each. In making these briquettes, the coal dust is first mixed with 10 per cent. of crushed pitch, and the mixture is fed into a vertical mill in which the ingredients are thoroughly incorporated by stirrers. At the bottom of the mill the ingredients encounter a jet of steam which melts the pitch and brings the mix­ ture into a plastic condition. The mixture is then fed into a revolving mould and the charge receives its ini­ tial pressure from a horizontal plunger. The mould then makes a partial turn and the partially compressed charge encounters another plunger which gives it the final pressure. Another partial turn brings the com­ pressed charge to an ejector which pushes it out of the mould into a trough, from which the briquettes' are removed by a boy on to a tray to be taken away for stacking. The briquettes are ready for use in about an hour from the time they have been delivered from the press. The action of the machine is con­ tinuous, the operations of moulding, pressing and ejecting being carried on simultaneously by means of the rotary mould block. The rate of ordinary working is about 14 briquettes per minute, or five tons per day of 12 hours, which can be increased to six tons if necessary by working at a higher speed. The machine can be erected at a comparatively small cost, and can be worked by unskilled labour. It can be driven either by horse or steam power, so that its services are available where steam is not to be had. The result of the burning of this fuel in ordinary grates was shown to be very satisfactory, a good bright fire being maintained without trouble and with but very little ash.

T HE estimated cost of production is 2S. 6d. to y. per 1 ton of briquettes, TABLE OF VARIOUS TYPES OF BRIQUETTE PRESSES.

� Pressure. ._i.gu ;::. I -5.::: 5l..: I System. �i�� ...... �"'� oo..b.o Lbs. per em. � g.::: square U u

--I -- ---

£ Tons. D. 10 Couffinhal 240-300. 1,529 7·5 2.1 LbS·1I 10 Yeadon - to 300 1,250 5 1.2 20 Middleton - Desom- 2,655 6 2.1

- - - - bay - 100' 10 Bietrix -- - - to 150 2,245 6 1.8 6 Dupuy (2 Presses) 100 1,400 5 1.4 10 Mageline.ta Presses) 100 3,800 13 1.4 I IT is evident by the above Table that the cost of plant is greater in proportion to the size of the briquette produced. 'B RIQUETTE plant �eldom needs repairs during the first year. G ENERALLY, modern machines use on an aver- age 6 per cent. of pitch, and the total cost ofproduc­ tion can. be taken during the first year at 3S. 4d. to 3S. 8d. per ton of briquettes, pitch being 4os. per ton. l""HIS last item is decreasing, and no doubt in the course of a short period, especially as the re­ covery of bye-products from coke ovens is now inter- 86

esting many coke merchants, the price of 1 ton of pitch can be taken at 20S. in which case the cost of production per 1 ton of briquettes would be 2S. 6d. to 3S. per ton.

The abore data does 710t include the cost of washing the coal.

T HE sale price of briquettes varies greatly in dif- ferent countries. In England briquettes fetch about the same price as best steam coal, and in Rus­

sia for locomotives on Moskau-Riazan fetch a they .. better price than English lump coal.

THE following Table gives comparative prices for 1885:

Briquettes. Lump Coal. Fine Coal.

------

England Cardiff, f. C. b. 10 6-11 6 I 10/- -12/- 4/3-5/6 (1885) II Swansea " 10/6 : 10;6 Newport II/- 9/- -10/6 5/- France Dep. Ahun 24 fro 22 fro 12 fro " I Seane-et- 30 fro 30 fro 16 fro I Loire-Epinac Germany Westphalia 6-8 M. .(1887) Russia : Moskau-Riazan 17·70 Rou. 14.65 Rou. I (1882) DESCRIPTION OF PRES�

FOR THE

PRODUCTION OF SMALL NUT BRIQUETTES.

�nterested in the manu,facture of patent fuel will be unanimous in declaring the _ALadvantages of briquettes of small dimen­ sions for domestic purposes, and will also doubtless agree that the most convenient shape is the spheric, or oval. THE advantages of briquettes of ovalo: spherical shape, and of about the size of an egg, are:- I. Easyadaption to automatic stoking. 2. Insurance of a good circulation of air in the furnace.

3. Less liability to break, having no sharp cor­ ners, consequently making little dust. and there­ 4. Insure a more perfect combustion, fore of great value for domestic purposes. SURFACE ARRANGEMENTS AT RYBNIK COLLIERIES WITH LUHRIG'S COAL WASHERS AND COKE OVENS.

/ / /# /' /' /' /# /' / /'

WINDING ENGINE

, ", ....

WASHING PLANT

SURFAOE ARRANGEMENTS AT RYBNIK OOLLIERIES WITH LlTHRIG'S COAL WASHERS AND COKE OVENS.

I I ,

"

... ------_--_ ..... _- ,_ - --- .. ------... ------_ --_ .. --- ... ------.. -- _ ------_ ..... - -- --_ ... ------.. _ .... - -_ .. ------_ ... - -- _._

... ----- ...... -- ... - J- .. ------.-- - - _ ... - -_ .. -_ ... -- _ ------_ ... - ---- .. ------. ------_ ... _ .. , r----- .. -_ -_ ..

RAM ENG I NET RAe K

P L A T

• i

C 0 K E BAN K

-F ¥

MAP OF SPREAD OF LUHRIG'S COAL WASHING AND ORE DRESSING PLANTS IN EUR0PE._

• MOLNEBO

EXPLANATION..

I EACH ROUND DOT THUS • INDICATES A

LUHRIG COAL WASHING PLANT� AND EACH SQUARE THUS _ A' o. LUHRIG LUHRiG ORE DRESSING PLANT� MINING AND OBE. DRESSING STARTED BEFORE 31sT DECEMBER, 1889. ENGINI;ER, DRESDEN,

SPECIALIST FOR ,DRESSIN� PL�NJ" FO� 'T.HE TREATMENT OF GOLD,. SILVER, LE:AD. ZIN_C� COPPE.R AND OTHER ORES. COAL. LIGNITE AND OTHER MINERALS. }44 PLANTS

WORKING PREVIOUS TO 1889, SOME OF 2.000 TONS

CAPACITY PER 10 HOURS. CONSTRUCTED ON LUtiRIG'S SYSTEM. MACHINERY MADE -'TO OUA OWN PL.ANSj

! . . '_._ cosr OF LOSS -_, . ._..cAPACITY, VYO.R,KJ�G AND GU_ARANTEE.P d' fe.' _'Z"tS IN. EVERY CASE. i PATENT COKE OVENS" WITH AN·q. WITHOUT RECOVER'I I ., � I OF BYE·PRODUCTS. p:; 1 � Z ...-t III 0

� CHAMPAHAC ] ...... • . J. l1.l NEVERS . VIENNA :r9' ...... \ • •• -.� I=» :...... -. ' 0 .... auo" PEST I=» •• ,.\ Z GRATZ � ...... -t , ' """" .. 'LVON ' : . E-I .. ·z • 0 0 • RODEZ � S .E z ...... A. cq -, .... 0 ...... •...... •..... ' ...-t � ...... E-I / cq / , ......

: .- � MADRID, .. 0 � � . E-I i ...... I=» ... _. cq .././ � LINARES • a: / f • � � ANDUJAR

�

'-4

- �

-4

c. LUHRIG WAS THE FIRST MINING ENGINEER 'TO INTRODUOE COMPLETE AUTOMATIC AND CONTINUOUS MACHINERY

INTO . COAL AND ORE DRESSING PLANTS IN' EUROPE.

CAPAOITY ... GUARANTEED. �. WASHING--...,.- COST OF . ----GUARANTEED. ,� IN - PERCENTAGE OF ASH WASHED OOAL .... -.GUARANTEED. � - - - - - REFUSE __ - - .... - - --..GUARANTEED. THE PLANTS BY CLEAN EREOTED C. LUHRIG UP TO D�ERI A CAPITAL OF 31,000.,000 MARKS, £1,550.000.

Facts and figures concerning Coal wa 111$�ImmImllMIIIIMIIII