a. i— w/\ 6 OZONE ROAD BRANFO9D 0640. ,CT 5 -£*"'•& TEL (203) 488-6348 tta'^ Sulfuric batch pickling process promise wasteo sn pollutioo ,n n

installatio. FirsS . tU n will soon check performance claims of a Canadian developed system.

THE FUTURE OF PICKLING MAY BE In describing its process KSF maintains that BRIGHTE smala f i Rl Canadian base e mistaked e pas s th beeengineerinth ha to f t o n i s e on g group F Chemica,KS l Processes Company (Scar- separat e difficultieth e f steeo s l picklind an g borough, Ontario) can substantiate the claims those of water pollution into two distinct prob- it is making about the pickling process it .has lems. KSF insists that it's the inefficiency of the developed. claimse Somth f eo : faster pickling traditional metho f picklino d g which rates, lower acid consumption o liqui,n d waste causes pollution problem y makin.B picke gth - discharge* Any one of these results, let alone ling process efficient, they say, one simultane- three, woul enouge db intereso ht t steelmakers. ously remove pollutioe sth n problem. In the next few months KSF will put its proc- Before describing the KSF process it's prob- ess linclaime eth when so n Atlantic Wire Com- abl gooya d ide enumerato at e majo e somth rf eo pany (Branford, Conn.) goes on stream as the difficulties which arise in sulfuric acid pickling.) first U.S. user of the process. Start up date is Once these are understood it's easier to under- now targeted for around September. stand just what KSF is trying to do.

COST DATA SUMMARY KSF Sulfuric Acid Pickling System Here are *he malor benefits claimed for Before Installation F F procestheKS KS s Acid used ...... 1000 t/y Steel pickled ...... 40,000 t/y e majoTh r benefits arisinF g KS froe mth Cos f removino t g pickle liquor ...... $25,OCO/y method of pickling, crystallizing, and recovery Water used ...... m [costgp :0 .$18,OOQ/y30 ) can be summarized as follows: After Installation Capital cost of acid 1. Constant fast pickling time resulting in plant, water treatment increased production. plant and fume collector 2. Recovery of up to 50 percent of the acid system ...... ;.....,.._...... _. - .$135,000 presently purchased. Total operating cost for 3. No delay in dumping and making up labor, power, maintenance, acid tanks. depreciation (10% year), 4. Eliminatio picklf no e waste disposal costs sludge remova chemicald lan s ...... $25,000 and problems. Saving acin so d recovery, 5. Recover percen0 9 f y wateo f to r purchased production increase, pickle for rinsing. disposal costs, sale of crystals, 6. Eliminatio fume th ef no proble - re y mb and water recovery ...... $72,000 covery of acid mist. Notes 7. Elimination of water pollution. Under the above conditions the KSF plant would pay for itself in 2Yz years. It takes approximately six months 8, Reductio hydraulif no c loa municipan do l to fully engineer, design, supply, install and start up a sewer and sewage plants. comolete system.

Reprinted from August 1966, 33/THE MAGAZINE OF METAIJ ffP&:9

VJ7

. I-WATE7-PICKLR PUME ACIP D PUMP 2-RINSE TANK 8-NEUTRALI ZATION TANK 3-PICKLE ACID DRAG OUT TANK 9-ALKALI STORAGE TANK 4-PICKLE ACID TANK ' 10-SETTLING TANK 5-ACID MIST FILTER II-RECOVERED WATER PU* 6-AIR PUMP

The Problems of Pickling The plant which overcomes the above prob- e majoTh r problems usually associated with lems* must ideally e simplB ) operat:1 o t e o es sulfuric acid pickling are: that qualified engineer t necessarno e r ar s fo y Acid-I) (1 t becomes progressively dilute y b d'"routin e operation corrosioe B ) 2 . n resistant the formation of ferroi£ sulfate. *** ^^anically sound so that it does not pose ^ „ . . ,. , „ , ., , a maintenance problem. 5} Be economically Spen) (2 t pickle liquor—Whe acie nth d becomes viable. ineffective it has to be disposed of in large quantities. * The KSF Approach Rins) (3 e Water-Large quantitie F acidifief feelo sKS s thaonlt d tno y doe process sit s deal rinse water also junkedhave b o et . witfoue th hr major problems ouclined earlier (4) Acid vapor—Emission of this pungent vapor but it thinks it does it simply and economically. cause pollutior sai n problems. compane Here'th w syho breaks dow attacs nit k

33/THE MAGAZIN METALF EO S ntODUCINC. •CtJS

e steeTh l enter sconventionaa l pickle tank (4) which is properly controlled r temperaturefo , , agita- tion (6)t and iron strength. It is then dunked in drag tank ()) to remove as much acid as possible prior to proper rinsing in tank (2). Pump (1) recircu* lates the rinse water via neutralization througid n an tan ) kclarifteh(3 a r (JO) for removal of iron and is returned by pump (11) via the cooling coils of pickle acid crystallizer (12) for re-use. e onlTh y variabl controo e irot e th n s li pickln i buil p eu d tank (4). When sufficient iro formes nha batce dth s hi rapidly pumpe crystallizeo t ) d(7 r (12). The previous batch having passed through the crystal vacuum box to re- move crystals has been waiting and pre-heated in tank (14) is immediately returned to the pickle tank (4) for pro- duction to continue. This operation is setako t minute0 e6 8 4 s o evert 4 y2 hours, consequently virtual continuous production can be maintained. The fume collectee sar d ove pickle rth e tank by a push-pull system into a ierylene filter collector and the acid u recovered 12-CRYSTALLIZER FOR IRON REMOVAL ' *** draina*e back to the I3-CRYSTAL VACUUM BOX 14-RECOVERED ACID TANK 15-RECOVERED ACID PUMP 16-ACID STORAGE TANK

on the few problems (which, as mentioned, they cause it dramatically affects the rate of reaction. seactualls a c singla y e interrelated problem): Good agitatio fundamentaf o s ni l importance to most chemical reactions yet the majority of d Problem:-KSAd e Th thay Ftsa if steel pick- p{cj.le plant3 don' d t^1* ad agitat .t ±d e ling is to be done efficiently it must not be re- KSF does agkate ^ £anks and says that the garded simpl methos a y f cleanin o dt ho evaporatio y b g n agitatior causeai y db n offsete th s sulfuric acid but as a chemical process. When increase of the acid solution which is caused by this is acknowledged then the conditions nee- heating with live steam. This eliminates the essar r efficienfo y t chemical reactioe b proble n ca n overflowinf mo g tanks and, more impor- firmly laid down. These conditions are: (a) tantly, concentrates the iron sulfate so that it can temperature control (b) good agitation (c) cor- be crystallized easily in the acid recovery plant. reel acid strength. Correct acid strength is related directly to the Temperature control is great importance be- " rate of reaction with iron and the subsequent

Aucurr 1966 rat f cleaningo e . Yet, says KSF, virtuall o n y connected with picklin say, gis s KSF longeo ,n r pkkle presen t plana s meane tha tth mainf so majoa ' r problem becaus provisioe th s f it eo n n\ taining consistent acid strength. proces r acisfo d recovery. The sulfuric acid i« allowed to be—me weaker _ _. ,4_ _ ., _ , „„ and weaker while the pickling takes longer and The Rinse Water Problem: In the KSF process longer. From a desire to cut costs the acid is th"es no need to dlsP°fse ofJarge quantities of allowe declino t d halefficieno s t e it f t strength acidified "nse water. After rinsing watee ,th ra before dumped. KSF says it maintains the acid pumped to a neutralization system, clarified of at its most effective strength. It does this eco- Ks lron and then "circulated via the cooling nomically by recovering acid from the pickling J°lls of *? crystalhzer. To maintain a fixed proces meany sb itf so s acid recovery unit. When >lanc impuritief eo rinse th en swateri per0 ,1 - enougsewee th d fres pickle ran o h£ th h f iro n builes makeui of ntanha p e n tu kth ru cen P. !S t batch is pumped into the crystallizer where the water is added. iro crystallizes i n ferrous a d s sulfat d eVapo Ad heptahy e rF proces Th ProblemKS -e sth n :O drate. The crystals are run into a vacuum filter a teryiene fibre instal!ed on the fume exhaust box where they are washed («nd possibly sold coljects add vapors and runs ±m to ^ ickle for pigment manufacture) aci= draine s di h .T d tan^ remOve-j k problee pollutiosr th ai f mo n off and pumped back to bring t up to strength. and simultaneously recovers waste acid. , . . t . e coolinTh s wate - ~c r f crystalwhice T useth s hn i -di convincn ca F KS e f steelmakerI - s tha• ti it. s proc f , - . .. , . s . hzatio„ n process is then utilized for steel nnsmg. ess fa ^ economica, and sim |ft to t/as „ Its thisi cooling system which helps over corro- ^m there shou]d fae a ^ ^ , ._ , ' . , „ - sion and/o . 1 r, maintenanc . e problems* . makers beating a path to their door. (For an _The Spent Pickle Liquor Problem: Spent pickle interview with the engineer-developer of the KSF liquor fousecone e th ,th r f majodo r problems process followine ,se g story.)

ATLANTIC WIRE COMPANY " —missio" : n arfd~enginee"rs representing^fhecbm- • Firsc- ti i•n thiie. U.Si.e. t.o instal. * lu a KSu'cF e unit- * thPane greeV wern e,igh helt wad san gived recentln by thy e(Marc Commissioh 1966n) a lon s gA standing practic Atlantie th eo procee t c d with F installatioKS e th f o n Wire Company (Branford, Conn. bees )ha n equipmen tordered whicha Deceme n hdw o - batch pickling wird witro eh sulfuri 1965, 7 cr . acihe d prior to drawing, in keeping with U. S. envir- "Basically, the new equipment will deal onmental trends, the company is now under with the spent pickle solutions in a manner orders fro State mth e Water Resources Com- which will recover all , extract ferrous mission to end pollution of the Branford sulfate crystals and effectively control and River with acid waste waters. trea remaininy tan g waste waters e aci.Th d William Hitchcock, Jr., presiden Atlanf to - wil usee lb d over again e ferrou.Th s sulfate tic Wire gives the following report on the crystals, looking something like rock salt, company's decision to be the first in the will be marketed, although the sales value - F systeminstalo KS t e . S th l :. U "Last Fall will largel offsee yb handliny tb d transgan - our representatives visited a KSF system in portation costs. a Canadian plant. Early in 1966 another plant "It will be the first unit of its kind in the in Canada installed similar equipment and United States and about the third in the steel this was also visited by representatives from industry anywhere." our company. Hitchcock commented further to 33; "In October we were sufficiently impressed "We're looking forward to the operation of desigo t F systena KS F sulfuri k KS t moas e suitablth c aci r defo system . Jus samee tth , the Atlantic Wire Company and in December you'll notice that we have a muriatic acid an order was placed for the necessary equip- () tank in our smaller pick- ment, subject to the approval of the plans ling room. There's no doubt that muriatic State by th Connecticu f eo t Water Resources doe n certai o sgooa b djo n kind wiref so . Commission. Wit investmenn ha t exceedin surface Th bettegs eI r than from sulfuric pick- $135,000 in this special equipment our com- ling. Also, there's much less chance of over pany had to make sure this method of solv- pickling. ing its industrial waste problem would be "Unfortunately, we can't run both acids satisfactor Commissione th o yt . Understand- F througsystee can'KS w e e o tus ms hth ably the Commission also wanted to be sure muriatic except for special wire. If we were this new system will correct Atlantic Wire's building a new plant and had the room I'd Industrial waste problem. Several confer- sure tak egooa d loo havint ka g both acids ences between representatives of the Com- working in my plant."

33/TWE MAGAZIN METALf EO S PXODUCINC