Document vV6jNV2erVX8ywNyG9dvRjgXq

00 127827 CONFIDENTIAL SECTION 2B CELL AND HYDROGEN AREA 2.0 PROCESS STEPS FOR THE CELL AREA 2.1 Detailed chemistry 2.1-1 List of chemicals Brine Salt slurry Burner grade HCL Cell effluent Vet chlorine Hydrogen Sodium sulphite Ethylene glycol Rav water Carbon dioxide Chlorinated water DOV CONFIDENTIAL DO 17782B CONFTDENTXAl 2.1-2a Raw materials and products Rav materials chemistry BRINE NaCl NaOH Ca Mg HYDROCHLORIC ACID HC1 Fe Ca - 18 X - < 5 ppm - < 2 ppm SALT SLURRY NaCl - 30 X settled volume Product chemistry CELL EFFLUENT NaOH NaCl NaC103 Fe Na2S04 Na2S03 - 120 gpl - 130 - 140 gpl - 0.1 gpl - 0.2 ppm - < 4 gpl - < 5 ppm HYDROGEN 02 C12 - < 2000 ppm - undetectable WET CHLORINE C12 H2 02 N2 C02 - 96.0 X - 0.2 X - 1.5 X - 1.0 X - 0.3 X DOW CONFIDENTIAL DO COMF1 DENT TAl Chlorine Cell Reactions Anode Compartment Reactions Primary reaction: (1) 2 Cl(-) ---------> C12 + 2e Competing side reactions: (2) H20 ---------> 0 + 2 H(+) + 2e (3) o + 0 -------- > 02(g) (4) C12 + H20 <---------> H(+) + Cl(-) + H0C1 Cathode compartment reactions Primary reaction: (5) 2H20 + 2e ---------> 20H(-) + H2(g) Side reaction: (6) 2H0C1 + OCl(-) <---------> C103(~) + 2C1(-) + 2H(+) electrolytic electrolytic chemical chemical electrolytic chemical DOW CONFIDENTIAL DO 127830 CONFTDFNTIAL Hov to vin CELL CHEMISTRY Vinning can be measured in the following ways: 1) > 98% chlorine yield based on power input. That is > 98% chlorine current efficiency > 96% caustic current efficiency 2) Extending the series life beyond the expected 4-5 years. This delays the expensive cell capital investment and returns the most money on the existing series. The trick, to this is to be able to increase the life without a decrease in the current efficiencies. The key to success lies in the ability to control reactions (2) and (4). (2) H20 --------- > 0 + 2 H(+) + 2e (4) C12 + H20 <-> H(+) + Cl(-) + H0C1 Reaction (2) is largely limited by itsovervoltage at theanode versus that of chlorine evolution. It is influenced somewhat by the molar ion concen tration in the anolyte next to the anode. In this way, optimum control of the anolyte resaturation helps favour chlorine evolution. Reaction (4) is promoted by high pH and low chloride ion concentration. High pH arises from back migration of OH(-) ions through the diaphragm to accommodate charge transport to the anode. The amount of OH(-) ions that backmigrates depends on the current density, hydraulic head differential in the cell, and the molar ratio of OH(-) and Cl(-) in the catholyte. Controlling cell effluent strength to strike a balance between evaporative energy to produce 50% NaOH and the ability to control anolyte pH yields optimum success. In any case the OH(-) ions have to be neutralized by pH controlling the cells with HC1 according to the following reaction: OH(-) + H(+) + Cl(-) ---------> H20 + Cl(-) The lower limit for pH control is set by potential damage to the magnesium silicate (asbestos) diaphragm. Experience has indicated that this value is around pH 1.5. Equation (2) can be suppressed by the presence of hydrogen ions. Equation (4) can be driven to the left by increasing the hydrogen and chloride ion concentrations. This indicates that good efforts to maintain a low pH in the cells will produce the desired results by suppression of hypochlorous production. DOW CONFIDENTIAL DO 127831 CONFIDENTIAL To increase the chloride concentration in the cell good control over the resaturation system is required. The only limitation here is that the saturation limit must not be exceeded lest a potentially serious situation arise from locally boiling and arcing a cell. This limit varies somewhat with cell effluent strength but can be usually fixed near 310 to 320 gpl NaCl in the anolyte. If reactions (2) and (4) can be suppressed we will be making efficient use of our electricity. With the conversion to M83 (metal anode) cells from the M82 (graphite anode) cells, the life of a series is no longer set by the physical deterioration of the anode. Some M83 cells have been on line for more then 5 years. This brings up the question of when do we rebuild. There is a definite benefit financially to delay the capital expenditure required for a rebuild. However it has also been shown that cell efficiencies drop off with age. The normal procedures for treating and washing a series will return some of the efficiency but not all. The trend is still downwards. The drop in efficiencies are probably related to wear and tear on the diaphragm. With time the diaphragm may be getting thinner and "looser", leading to increased backmigration of the OH(-) ions. Ions that have to be neutralized with HC1. This is represented by a drop in the caustic current efficiency for that series. The present challenges in the cell area is to define at what point the economic benefits of delaying capital costs are overshadowed by efficiency penalties, and to find a way to extend the life of the series while maintaining high cell efficiencies. DOW CONFIDENTIAL DO 127832 CONFTDFNTIAl \1 SIMPLIFIED DIAPHRAGM CHLORINE CELL Anoda Aaactlon 2NCI -- Cl, + a*`+2N* * DO 1 ? 7 8 3 3 C O N F ID F N T I Al. Thermodrnaalc Calculation* Anode Side Primary Reaction 1. 2C1" __ Cl 2 + 2e 2( - 39.952) 0 Ah| +79.904 Teal or 79.9 Teal --------------- - 2 gm equiv.vt. Competing Reactions^ 2` 2H2C1) "" 2C-68.315) 2(s> + `H+ + " A HO H +136.6 Teal or 68.3 Teal - r- " 2 gm equi+.wt. 3. Cl2(g) + H20(1) -m- HOC1 + H+ + Cl- (-68.315) -28.9 0 -39.952 AHJ -Hr- -0.537 Teal 4. 6CL0* + 3H20 --2C103` + *C1_ + 6H+ + 3/22 + 6e 6(-25.6) 3(-68.315) 2(-23.7) 4(-39.952) 0 0 AH| -Hr- +151 Teal 5. HOC1 --& + OC1" -28.9 0 -25.6 ro . +3.3 Teal -- r_----- A1 oo 127834 CONFIDENTIAL Cathode Reaction Primary Reaction 6 2H2 --*" 20H" + H2 + 2 2(-68.315) 2(-54.97) 0 H +26.69 Real *------T----- --- -- - - Ah| Competing Side Reactions 7 3H0C1 + 30H" --- 3HjO + ClOj' + 2C1" 3C-28.9) 3(-54.97) 3(-68.315) -23.7 2(-39.952) AHJ -56.939 Kcal <z. OCl~ + 2H0C1 --2H+ + CLOf + 2C1* -25.6 -2(28.9) 0 -23.7 -2(39.952) ----Hr_--+-----.2..0-.-2---K- c--a-l l. H2 + Clj--**- 2HC1 00 2(-22.06) -44.12 Xcal AhJ >o. + 0j 00 IHjO 2(-59,56) H? + -119.2 ICeal Aa| AH HO 177835 CONFTDENTTAl Free Enry Calculation! Primary Reaction 1. 2C1" --e- Cl2 + 2e 2(-31.372 0 dG System +62.74* Kcal 2. 220(1) 2 + + * 2(56.687) 0 0 dG System 113.37 Kcal ^G| Ac 3. 6C10" + 3H2o --*- 2C103 6(-8.8) 3C-56.687) 2(-0.8) dG System - 95.77 Kcal 4C1" + 6H+ + 3/202 + 6e" 4<--31.372) 0 0 ACJ 4. Cl2(g) + H20 H0C1 + H+ + Cl- 0 -56.687 -19.1 -31.372 AGJ dG System 6.215 Kcal Would have to he checked 9 actual cooc. 6 temp* 5. H0C1--^ A* + 0C1" -19.1 0 -8.8 dG System - 10.3 Kcal AC| Would have to he checked actual cooc. I temp. 6. 2e + ffljO --- H2 + 20H 2(-56.M7) 0 2C-37.59* dG Syatem * 38.186 DO 127836 CONFIDENTIAL *7. 0C1" +2HOC1 2H+ + C103- + 2C1" -8.8 2(-19.1) -0.8 2(-31.372) AC| dC System * -16.544 Real H2 + Cl ^ 0o 2HC1 2(-22.78) <JG System * -45.56 Keel AG S. 2H2 + o2--* 2H20 0 o 2(-54.63) dG System -109.26 Real A<^ D0 127837 CONFIDENTIAL rmrall Reaction Thermodynamic 6 H 2C1" + 2H2o --C12 + H2 + 20H 2(-39.952) 2(-68.315) 0 0 2<-54.97) HO +106.59 Real _ r g mole h H GibbsFTMEneTgl Table 9-2 Lange'* Handbook Chemistry 11th. Ed. 2C1" + 2H20 ci2 + H2 + 20fl` 2(-31.372) 2C-56.687 0 2(--37.594) C 100.93 Real AG 2C1" 2H2o Cl2 + 2e Hj + 20H- +2e l - -1.359 l - -0.828 -2.187 AG nFE (eg 7.D Daniels & Alberty. Pg.247 -2(23,060 Cal) (2.187v) * 100.905 Real Volt Gibbs free energy from dG System - AG product. - ACf Reactant. 2C1* ci2 + 2. 2e + 2H2o H2 + 20- dG System - 62.7U + 38.186 - 100.830 Real OO 127838 CONFIDENTIAL 2.1-2b By products and impurities. IMPURITY SOURCE EFFECT NaOH Na2C03 NaOCl Fe Ca Mg Trace metals Fe Ca NaOH NaOCl 02 C12 H2 brine HC1 Salt slurry Cell effluent Hydrogen Chlorine Increases acid consumption Increases acid consumption and produces C02 vhen neutralized. Corrosive to carbon steel. Produces H2 in the anolyte compartment. Plugs the diaphragm resulting in a wash. Plugs the diaphragm resulting in a wash. Poison the anode reducing efficiency. Produces H2 in the anolyte compartment. Leads to diaphragm plugging. Increases acid consumption in the cells. Corrosive compound. Reactive Chemical potential. Environmental concern. Reactive chemical potential. DOW CONFIDENTIAL `27B34 AV- 2.2 Basis for Design Equipment Design capabilities Actual Rectifiers M83 cells V101 P101 EJ140 T140 E140 P140 70 ka 930 v each 68 ka 850 v 2.80 v @ 60 ka @77 Deg C. 98.7 X C12 eff. 95.0 X CE eff. 0.6 X 02 in C12 0.05 X H2 in C12 1.01 ACKVH/LB C12 1,000,000 lbs/hr brine outlet pH 1.9 v @ 60 ka 98.5 95.0 0.2 1.06 1,100,000 lbs/hr brine outlet pH 1.9 1,100,000 lbs/hr Cell eff. 1,220,000 lbs/hr Cell eff 16,000 lbs/hr of H2/H20 at 80 Deg. C. 4 cm backpressure on the cells 25,000 lbs/hr H2/H20 at 75 Deg. C. 7 cm backpressure on the cells Scrub 4,700 lbs/hr H2/H20 at 35 Deg. C. 6,000 lbs/hr H2/H20 at 35 Deg. C Shell & tube 12,500,500 BTU/hr Plate and frame 22,400,000 BTU/hr 800,000 lbs.hr of H20 1,000,000 lbs/hr of H20 DOV CONFIDENTIAL DO 127840 CONFIDENTIAL 2.3 Process flowsheets 2.3-1 Process description and flowsheets. Treated brine flows directly to E330 or to E331 via T250 the tailgas scrubber from the brine ponds (flowsheet 1). The brine is cross exchanged with condensate from the caustic plant to bring the temperature of the anolyte in the cells up to 80 degrees Celsius. Each series has an individual temperature controller that feeds auxiliary (cool) brine into the series to maintain the temperature of the anolyte at the desired set point. The heated brine from the exchangers enters V101 (flowsheet 2) the head tank. Chlorinated water from V107 and from V109 also enters the head tank. 18% hydrochloric acid from V165 is added to the head tank to neutralize any caustic that may be present in the brine and to reduce the pH of the brine to 1.9. The brine then flows by gravity to the chlorine cells via a radial feeder system. Besides this system there is also an auxiliary system to supply cool brine directly to the cells from the treated brine pumps. This system is normally used on start up of the cells when the brine demand is higher due to loose diaphragms. The chlorine cell area consists of 8 series of 72 M83 cells. The 8 series are divided up into two circuits of 4 series each. There is a rectifier for each circuit, R3 and R4. AC power is supplied to the rectifier and is converted to DC power before being fed into each circuit (flowsheets 3,4). The rectifiers are Fuji S-former outdoor type. Cooling for the rectifier is supplied by circulating deion water cross exchanged with cooling tower water. In the transformer, oil is circulated and is also cross exchanged with cooling tower water. The rectifier cubicles are cooled with air that is circulated by fans. Each series in the cell area is coupled with the neighboring series to form a series pair. Each series pair can be isolated from its rectifier circuit by the means of Anderson switches illustrated in figures 1 and 2. Should a pair of series need to be isolated for rebuilds or washing, it can be done with minimal effect on the availability of the plant. DOW CONFIDENTIAL DO 1.27841 CONFIDENTIAL Salt is removed from the cell effluent in the caustic plant and forwarded to D150 (flowsheet 5). In D150 the salt is washed with brine through a sparger system to remove any caustic that has been carried over- The sparger system maintains the salt in D150 in a fluid state. The overflow from D150 flows into V413. V413 over flows into the brine ponds. The salt slurry is fed into the series through the radial feeder system to maintain anolyte salt strength at about 295 gpls. The salt concentration is maintained in D150 at about 30% settled volumes. There is enough salt in D150 to provide the cells with salt slurry for 5 hours if the caustic plant stops forwarding salt during a flywash. HC1 is added to V101 and to individual series through a header system from V165. Burner acid flows to T110 at a concentration of 34%. It is then diluted in T110 and forwarded to V165 where the concentration is maintained at 18% by a density controller (flowsheet 6). The acid is forwarded to V101 and the cells by P165. The acid is used to neutralize any caustic in the brine and caustic that has back migrated through the diaphragm. The typical chlorine cell is illustrated in flowsheet 7. The main products from the cell are chlorine vapor, hydrogen vapor and cell effluent (10% caustic). These products leave the cells through separate collection headers. Figure 3 is general overview of the flows in and out of the cell area. Due to impurities that are in the feed to the cells, the diaphragm plugs up with time to the point where it needs to be washed. A pair of series are washed at a time. The cells are washed with raw water that is heated in E104 (flowsheet 8). C02 is also added to the raw water to lower the pH of the wash water. The cell effluent flows from the series and is collected in the sump S101. The cell effluent is then forwarded to the cell effluent storage tank D301 (flowsheet 9). Sulphite from D170 (flowsheet 10) is added to the sump to neutralize any hypo that may be present. The chlorine leaves the cells under a slight vacuum and flows to the primary chlorine cooler E101. Each pair of series is coupled through a knockout pot which serves to disengage any entrained water in the chlorine. The hydrogen leaves the cells under a slight pressure. Each pair of series connected through a knockout pot. From the pot the hydrogen can flow to either the start up header to T142 or to the primary hydrogen scrubber T140. In the event of a problem with the primary stack the flow can be diverted with a seal to T141 the primary relief stack. Each knockout pot is also equipped with a relief stack to protect each pair from excessive hydrogen backpressure. DOW CONFIDENTIAL DO 12784? CONFIDENTIAL The hydrogen system (flowsheet 11) consists of an ejector which provides cooling and a slight draft to force the hydrogen through T140. All of the hydrogen in this plant is vented except for a small portion which is compressed and forwarded to the BC1 burner by K150. The motive fluid for the ejector EJ140 is recirculated through E140 by P140. E140 provides the cooling necessary to cool the hydrogen from 75 degrees to 40 degrees. Because of the cooling the H2 system has a net gain of water which overflows to the brine ponds at T140. Sulphite from D170 is added to P140 suction to neutralize any hypo that may be present. The brine is cross exchanged with condensate from the caustic plant to bring the temperature of the anolyte in the cells up to 80 degrees Celsius. Each series has an individual temperature controller that feeds auxiliary (cool) brine into the series to maintain the temperature of the anolyte at the desired set point. DOW CONFIDENTIAL 00 177843 CONFIDENTIAL AS'S'OC. LiKUbP V'41-. iZ. k.t`_ M_J BRINE ASSOC. D i F'LhY'z T'Z*=.~ --JZ. j"7:*=--i:,--Njru. j3 _ 3 LJ1 *1r- \,f - i~i - ' '1PDT30E0 - fE30S FT3016 a- : " TE3018 HEATING JE34 - *-t i FT3825 _ 1.4 Lr'_ < M i TE3023 TO 031 FRO VPF V30 E30 < c-il PDT30S8 TE3032 X It. -m TE38E6 FT3033 TE3031 11:4:84 12-0CT-88 : ', IE l-M^R-E'E O.E- HO 1?7B44 confidfnttai. pLc_ii cccn ucAn I L L U 11 L fi U V ji a0 ii ti n<nmii vis nr GROUP 0c c8 C"lE3 Hbc'SJL . 0ISrLAYS i 0150 pzr.rr, ^PT4@S_. T-__ -^-i Oz-C----*-7F f )3 ' '~FT4l57' ;i_ / 1 Cf"7=; . I-tji tfI i1 TE3022.1 iif' 0 s = 4 . pc-- FT3&16 ->4- TE3030.1 FT133 FT1145 53.9 KGM F*..... fi 400 LPF FT1023' VI65 HC CL2 H TO E16 PHT1082 .37 PH PHT1080 .17 PH Lp~T71035ill " TO S-: 1 TO s-: j. TO S-t f TO O""-. ? TO S-- i TO * TO S-c \ i__ TO S-: @5=53=49 14-0CT-33 ! - - ipr-: : D.B. DO 127846 CONFIDENT T Al jr.-`L=r C !i 1 T DCTT K T CD D1 i ij >J i IS L i i I i U IS IS v1 DISPLA'i 4.l C TE1601 1i 1i h I r LT16S0 W< y <* TEi0 TE1607 TE160S TE1635 NDING 7= TE1636 7F 7 Hn mu ct . fi Clil* :M0 CT1617 09-52=43 14-0CT-88 iVISED 25-MAP-= D.B. fMlii DO 127847 CONFIDENTIAL R 3 CIRCUIT SWITCHING PROCEDURE 'v DATE: ( o ) REASON FOR SWITCHING: R3 (b) OPEN THE FOLLOWING SWITCHES: L 2. 3, 5.. 6.. (c) .CLOSE THE FOLLOWING SWITCHES i * 2. 3a 5_ DO 127849 CONFIDENTIAL DIAGRAM COMPLETED BY^ SWITCHING COMPLETED BY: SWITCHING CHECKED BY:, R4 CIRCUIT SWITCHING PROCEDURE DATE: R4 (a) REASON FOR SWITCHING: (b) OPEN THE FOLLOWING SWITCHES: . \ ,2. 16 5*. (c) .CLOSE THE FOLLOWING SWITCHES 4. _ 25.. 3. 6.. DO 127850 CONFIDENTTAl DIAGRAM COMPLETED BYl_ SWITCHING COMPLETED BY: SWITCHING CHECKED BY:, ^ t r*r\ MTDAI i DO 1 2 7 8 5 ? C O N F ID E N T IA L Ff! P150 FS V10 SOUTH SOUTH ! LTi1--21'3M.1 PHt10C8't_6* .2 PT1453 -3.43 CM P ' i TO K1l PT1528 4.35 CM F'--S----------- >TO Tl* L 4TO Tl* ASSOC. DISPLAYS T140 T142 V101 S101 VI65 D150. Kiel" LT1213.2 8.78 CM NORTH PHT1Q36.1 2.29 FH =S NORTH HSS1.1 "31.1 ndSl. 1 C02S1. CL2S1. H2S1.2 02S1.2 N2S1.2 C02S1.2 CL2S1.1 ;--3 r '_. -! R3 AMPS IQY166S SI VOLTS ET1215 VXCELL ET1215S1 \R l k. 05=12=04 14-0CT-86 D0 177853 CONFIDENTIAL CHLOR ALKALI II CELL AREA FLOW SHEET DO 1278S4 CONFIDENTIAL FT1447 FT1456 t'JItr :r jr r i @S:43:7 14-0CT-88 DO 127855 CONFIDENTIAL SUMPt i LL C C C { L U I L i ! L L I* ! ASSOC. DISPLAY1: SULPHIDE FFOft -s.- LIC103S iPtP 7 LP': FT1040 1018 TO 038: 7-' ^ POT LTi36 08=06=55 14-0CT-88 278^6 DO * DENTT Al conf1 SULPHITE DISTRIBUTION 05=54=18 14-0CT-S3 liEZ 3-f*AR-S8 D.B. DO 127857 C0NFID5NTIAI SYSTEM N N2 ------- tSl^SE I 4- T S-S3/34 1 | 2--5-^36 S-S7/S8 I 4 FT1437 _ Ft fl3 KGS + ----------F------- ------------V+ ,EI4f33, TE1343 35.4 C T r ,*= ~iii TE1342 46. C T FT1322 SERVIC MATER OUT FT1533 :. 17 K.G3 SERVIC MA i tR IN 3=16=54 13-0CT-38 j~N A. D. D0 127858 CONFIDENTIAL 00=13=15 14-0CT-33 D310 FROM ,, T140 t i_ --------------------V4-------------------57. 59.6 C -- "-1 TO R601 Je SEWER i V151 DO 127859 CONFIDENTIAL 00 127860 C O N F ID E N T IA L 3.0 Process control unit 3.5-2 Critical variables Variahle Reason critical Low V101 level An overflow results in a chlorine emission to the environment. 502 Low level could starve the cells of brine hence lowering head levels to a dangerous point. V101 pH Low pH could put the cells in danger of being acidized. 1.0 Normal High 802 902 1.9 3.0 High pH out of V101 leads to high flew of acid to individual series leading to localized acidizing of the diaphragm. V165 HC1 concentration Concentration swings upset 152 182 202 the pH control in V101 aid the series leading to poor efficiencies and possibility' of acidizing the diaphragm SERIES ANOLYIE Head levels Lew head level could lead to mixing of H2 with C12 8cm 45cm DCW (XNFTEENITAL Control logic / protective devices - overflew alarms. - Dual level indicators - Low level alarms on V101 - Low level alarms on cells - Automatic make up of brine through auxiliary system to cells. - Dual pH probes with feedback control. - Dual pH probes on cells with auto selection of the lowest reading. - Deviation alarms to warn of bad pH readings - High flow limit on the acid to the series. - Density control loop on VI65 with condensate make up. - Two level transmitters with alarms and select - Low low level alarm. Audible in the field, visible lights Variahle PH salt Temp fill. EFFLLENT Strength Hypo GETtEAL Volts Reason critical Low Lew pH could lead to acidizing 1.0 the diaphragm. Normal High 2.0 4.0 High salt could lead to 270 295 315gpls arcing in cell. Lew salts lead to inefficient operation. High tenp could lead to damage to the cell body. 85 c High caustic strength in cell 100 120 14Qgpls leads to high tenperatures and inefficient cell operation. High hypo indicates a week diaphragm and inefficient cell performance. Very high voltage could indicate a an arcing cell. 0.0 5.0ppm 3.0 v 4.0 v Control logic / protective devices - Two pH probes in the same cell with an auto select of the lower reading - Flew limit through the control valve - Manual sarples each drift to check - Weekly profiles of series to determine lowest cell for probes. - Treatment program to line out pH's. - Trip control valve close if series shut down. - Samples each shift - Trip slurry flew if series shut down - Two temperature probes in the same cell with alarms - Deviation alarms - Tie in to aux brine loop to provide cooling. - Manual sanples each shift and head changes to correct - Washing of cells to reduce gpls - Weekly profiles and treatment with asbestos pulp to line out individual cell strengths - Sanples each shift - Profiles when needed and treatment - of cells containing hypo. - Rate of change alarms on the voltage - Weekly profiles to monitor for changes DO 1.27861 CONF TDFNT TAI COW OCNFTTENriAL Variable High start up brine flows. H2 cone in C12 High H2 pressure Lew H2 pressure High C12 Pressure Low C12 Pressure Reason critical Lew If the series does not get get enough brine upon start up loss of head levels could be experienced. Pinching back the CE header valves to maintain head could lead to cathode ccnpartment being flooded. Both situations could lead to an explosive condition. Reactive chemical potential Normal High 3.5 2Cgpm 0.0 O.S Reactive chemical potential 0.0 4.0 10.0 cm vc H2 could back up into C12 Reactive chemical potential vac 4.0 10.0 cm vc could pull 02 into H2 Industrial h/giene concern -6 -3 pos cm vc Release C12 to atmosphere. Reactive chemical potential -6 -3 pos cm vc Could pull H2 into C12. Could collapse &2 piping Control logic / protective devices - Start up to trench and not to snip - close monitoring of head levels - Modifications to aux brine system to provide more brine - Two cn-line G.C.s - Fast scanning of individual series available for start ups - Each series pair has a relief pot see attached diagram - H2 pressure transmitter vith alarms - 02 analyzers on the H2 system vith trips - Pressure transmitters and alarms - G.C.S and alarms - Pressure transmitters and alarms - Vacuum break on the piping o oz Oo -n o"0 "-ovl z cd -Mt OM' Note: Please see the attached diagram for an over view of all the equipment available on the series. DCW ONFUENITAL DO 1 P 7 8 6 3 C O N F ID E N T IA L H2 RELIEF/COLLECTION OWB* W-SK-05 DWN BYi SJ*OTTER INSTRUMENTATION ON TYPICAL SERIES DO 127864 CONFIDENTIAL DWG* *0-SKDWN BYjS-POTT