~ AP42 Section: 1 .I Reference: 67 Title: Results of the March 1990 Trace Metal Characterization Study on Unit 3 at the Sherburne County Generating Station. Interpoll Laboratories, Circle Pines, Minnesota. June 7,1990. RESULTS OF THE UARCH 1990 TRACE METAL CHARACTERIZATION STUDY ON UNIT 3 AT THE SHERWRKE COUNTY GENERATING STATIM i I- - Interpc!’ Lsboratories, Inc. 4500 Ball Road N.E. Circle Pines, Minnesota 55014-1819 TEL: (612) 78’6-6020 FAX: (612) 786-7854 RESULTS OF THE MARCH 1990 TRACE METAL CHARACTERIZATION STUDY ON UNIT 3 AT THE SHERBURNE COUNTY GENERATING STATION Submitted to: NORTHERN STATES POWER COMPANY West of Highway 10 Becker, Minnesota 55308 Attenti on: Bob Catron Approved by: Report Number 0-3005 June 7, 1930 PL/prp TABLE OF CONTENTS 1 INTRODUCTION I 2 SUMMARY AND DISCUSSION 4 3 RESULTS E, 3.1 Results of Orsat and Moisture Analyses 10 3.2 Results of Multi Metal Modified Method 5 Sampling 14 3.3 Results of the Hexavalent Chromium Sampling 17 APPENDICES: A - Sampling Train Calibration Data B - Location of Test Ports C - 4M5 Field Data Sheets - SDA Inlet D - 4M5 Field Data Sheets - Stack E - Chromium Sampling Train Field Data Sheets F - Laboratory Data Sheets for Method 3 G - Results of Trace Metal Analysis H - Results of Lime Analysis I - Results of Trace Metals Analyses on Csal Sample J - Procedures K - Calculsrior Equeti~xs ii ABBREVIATIONS ACFH actual cubic feet Der mlnute cc tml) cubic centimeter (milliliter) DSCFH standard cubic foot of dry gas per minute DSHL drv standard milliliter DEG-F (OF) degrees Fahrenheit DIA. d iame ter FP finished Droduct for plant FT/SEC feet Der second gram GPH gallons per minute GR/ACF grains per actual cubic foot GR/DSCF grains per dry standard cubic foot g/dscm grams per dry standard cubic meter HP horsewwer HRS hours IN. inches IN.HG. inches of mercury IN.WC. inches of water LB DOUnd LB/DSCF pounds wr dry standard cubic foot LB/HRC pounds per hour LW10 BTU pounds Der million British Thermal Units heat input LB/HHBTU pounds per million British Thermal Unlts heat input LTPD long tons per day MW megawatt mg/Nm: milligrams per dry standard cubic meter uq/Nm' micrograms per dry standard cubic meter microns (urn) micrometer UIN. minutes ns nanograms ohm-cm ohm-centimeter PH particulate matter PPH pounds per hour PPH parts per million DDmC parts Der million carbon DDm.d Darts per million. dry DDm.W Darts Der million. wet QDt Darts per trillion PSI pounds oer sauare inch SP.FT. sauare feet T PD tons per day US micrograms v/v percent by volume w/w percent by weight < -< (when following a number) Standard conditions are defined as 68 OF (20 OC) and 29.92 IN. of mercury pressure. iii 1 Jeff Cole, RTI, says this is a dry bottom boiler, according to I the UDI/EEI database. Jeff has been working with the NSP data for five years and, therefore, I am taking his word on this. 4 Jj 1 1 I' 1 INTRODUCTION ?r H?rci 27, !9W. Int2rzc! 1 i3isratsr:er personnel 23ndgcted a trace ?letal characterization study on the Unit 3 Dry Scrubbing System at the NoTtnern States Pcwer :Company (NSP) Sherburne County Ceneraticg Stst:sn loc3T.ea ii: Pxk2r, M:nne;c.ta. 3n-s;:e t2sting was performed by 3. 'Vu Koever, E. Tr~bridge, Y. k'aehler axd C. 3ainville. Cocrdinstizr be-ween testicg act7v:ties and Jlan'. operation w2s provided by Bob Cat:on of NS?. IJn't 3 is a Babcock and Wilcou. 8€0 MW boiler which came on lice In 1927. The boiler is flred with Fulvsriiad subSituminous :oal from Montma. Particulate and sulf?lr dioxid? ecjssims are ccntrolled b:: 3 dry scrubber consisting af a sprzy dryer abjorber (SIX) and tagP.cuse. Scrubbed flue gas is exhausted t3 the atmos3here by a 952-foot high radial brick-lined corcrete .stack. Yulti-Metal Modified Method 5 (4ME) sampling train was used to isokinetica!ly collect sclid and vapor phase trace metals. The samples 'were crrllected and analyzed as per the EPA Draft Method "Methodology far the Determination of Metals Emissions in Exhaust Gases from Stationary Source Combustion Processes". The aerosol or solid phase trace metal samples were collected on high purity Pallflex' filters. The vapor phase trace metals were collected in an all glass impinger train. The first and second impingers each contained :00 cc of a mixture of 5% HNO? and 10% H,O,... The third and fourth impingers contained 100 cc cf a mixture of 4% KMnC, and 10% H,SO:. These impingers collect any elemental mercury which might penetrate the first two impingers. The recovered four-part trace metal samples ware returned to the laboratory where the prob? rinse, filter and nitric acid impinger cat.:h &re smbined, dissc:ve,j in acid (inclJd:;.c the gls; fiber fiiter! and 5na:yied by Inductively Coupled Argon Plasma Emission Speztrometry (ICP). I In scme cases, the same here reanalyzed by grachite furnace atonic li absorption spectrometry fer grezter sensitivity. The permanganate mersiry catch and en a?icuot of the frcnt balf. cz:ccI were enalyred by .:olb vap?r s atomic abscratior. spectrometry :CV/AC;. Twc field-biased b:anks 'e?~ collected and recovered at each test site and analyzed with the field 1' samples. ?he CrlVI) samples *e-e co??ected*.ith ? Modified Method I? sampling Y train withcut the cptional filter. Pallflex'. Type 2500 QAT ultrapure filters were used in the post-impinger filter holder in place of the normal glass fiber fllters. The sampling train was rigorously cleaned prior to sampling to remove any traces cf organic materials which react rapidly tc reduce Cr(V1) to Cr(II1). In addition, nonorganic vacuum grease was used to sea! all ground glass joints in the sampling train. A heated glass-lined silmpling probe was used to extract the samplos from the stack. The first two impingers were charged with 1 N NaOH which acts as a preservative. The samples were collected following Method 5 sampling protxol. After completion of sampling, the frc4 half of the train was recovered using 0.5% Na,CO:... The backhalf was recovered using 0.1 N Na@H. The recovered samples were stored at 4 'C until analysis. In the laboratory, the three-part field sample was combined, pH adjusted, APDC chelating agent added and extracted with MiBK. The MiBK was then evaporated and the residue taken up in nitric acid. The extract was then analyzed by ICP in accordance with EPA Method 6010. An integrated flue gas sample was extracted simultaneously with each particulate and sulfur dioxide sample using a specially designed gas sampling system. Integrated flue gas samples were collected in 44-liter Tedlar bags housed in a protective aluminum housing. After sampling was complete, the bags were sealed and returned to the laboratory for Orsat aralysis. Priyr to sampling, tne Tedlsr bags are leak, checked at 1:. 2 IN.HI;. v3cuum w3;h a? in-line -stmeter. 332s with any detectable inleakage are discarded. Testing on the SDA Inlet was conducted using a singls point traverse. Each test run was 60 minutes in duratior. Testing cnthe Stack was conducted from four test ports oriented at 90 degrees. These test ports are ,located seven stack diameters downstream of the breeching inlet and eievsn diameters upstream of the stack exit. 4 16-ooint traverse was used to extract representative trace metals and chromium VI samples. Each traverse point was sampled four minutes to give a tota? sampling time of 64 minutes per run. The important results of the test are summarized in Section 2. Detailed results are presented in Section 3. Field data and all other supporting information are presented in the appendices. 3 2 SUMMARY AND DISCUSSION The results of the trace metals determinations are summarized in Tables 1 and 2. Chromium VI results are DreSented in Table 3. The mass rates of trace metals determined at the Inlet sampling location, when stoichiometrically converted to the appropriate or actual species, and adjusted for unanalyzed species such Si02, Ti02 SOj and P20j give total particulate mass flow rates which agree very well with the total inlet particulate mass flows measured on August 9, 1988 when a complete duct traverse (48-points) was performed as shown below: Particulate Mass Rate LB/HR Calculated from Measured Trace Metals Run 3-27-90 8-9-86 1 32300 44300 2 472@0 4420@ Average 39700 42300 The above calculated mass rates for 3-27-90 do not exhibit good agreement with the particulate mass rate calculated directly from a gravimetric analysis of the trace metal samples (71,000, 67000 and 28000 LB/HR). This is not surprising inasmuch as the 3-27-90 sampling consisted of a 3-point traverse. This data suggests a severe stratification of particulate mess flaw in the inlet dxting. Some contaminatiop occurred of the Run 1 sample :,Zliected at the stack test site uh:ch invalidated the Run ! results for arsenic, cadmium and zinc. This contaninaticn did nct effect cther trace Elements nor vas it observed in the subseqirent test rcns. P No other difficulties were encountered in the field or in th6 la’soratsry eveluation of the samples. On the basis of this fact ane a complete review of the entire data and results, it is our opinion, subject to the above qualifications, that the results reported herein are accurate and closely reflect the actual values which existed at the time the test was performed. E Table 1. Results of the March 27, 1990 Trace Metal Determinations on the Unit 3 Dry Scrubber System at the NSP Sherburne County Station in Becker, Minnesota.