Document qaGqreRpMD8z2x4847RZeOdbK

(conoco) Interoffice Communication to P. C. Gowan Frorn G. D. Johnson oace February 28, 1977 suD,ect Closed Benzene Sampling Systems (PE-49) Des. No. 734-ETH-177-GDJ Final Issue Attached is a class "A" design for improved benezene sampling systems in the Ethylene Unit. The current sampling methods are not suitable to meet the proposed OSHA standard of 1 ppm for two hours exposure. Strahman sampling values are specified for the quench water, light aromatics, and heavy aromatics streams. These valves eliminate the need for line fludring and have proven satisfactory for the Baltimore Chemical Plant benzene fume abatement program (Table I). liquified gas type streams, including the caustic tov/er overhead, demethanizer bottoms, deethanizer bottoms, and deoropanizer bottoms, will continue to be sampled in metal samole bombs, but with closed sampling manifolds which vent to a. new vent collection header. Sampling procedures are attached which detail the sampling techniques. Following installation of the design, a survey should be taken to assure meeting the OSHA standard. A separate Turnaround Work List is attached for those design related items which need immediate attention. This work must be expedited by planning in order that the valve installation and tie-ins be made dur ing the April turnaround. Anyone having questions concerning the design, please advise. G. D. Johnson, Environmental Health Engineer Approved GDJ/psm Chief Process Engineer Attachment CC: RAC, :RHG, WJR, BRD, RLP, WAM, SMF, HGH, WWC, GDO, KOB, JEC, DHS, PEC, FILE, RDG TABLE I CONTROL OF BENZENE EXPOSURE WITH STRAHMAN SAMPLING VALVES (BALTIMORE PLANT DATA) Sample Point: Benzene Dryers SAMPLE NO. 1. 2. 3. 4. 5. 6. 7. MEDIAN BREATHING AIR SAMPLES WITH LINE FLUSHING 20 (ppm) 2 4 1 2 10 10 4 WITH STRAHMAN VALVE -^1 (ppm) 0 0 1 2 0 1 SAMPLE NO. 1. 2. 3. 4. 5. 6. 7. MEDIAN DOWNWIND SAMPLES WITH LINE FLUSHING 70 (ppm) 40 60 1000+ 40 30 50 --5G------- WITH STRAHMAN VALVE 1 (ppm) 0 0 1 16 2 1 Measurements by Century Organic vapor analyzer. Model OCA-118. ENERGY IMPACT STATEMENT FOR CLOSED BENZENE SAMPLING SYSTEM There is neither an energy increase or reduction with this design. oooo^869 TURNAROUND WORK LIST 1. Install a 3/4" Strahman sampling valve on the 2h" product line at the outlet of the debutanizer bottoms cooler, EA-415. .8 Install a 3/4" Strahman sampling valve on the 4" quench water blow down line at the settler drum. 9. Install a 3/4" Strahman sampling valve on the quench water circulation line (16"-QW-100-A2A) beneath the settler drum. 10. Install a 3/4" Strahman sampling valve on the heavy aromatics product line (1V-P-151) downstream of control valve LCV-101. 21. Provide a 3/4" Stainless steel bleeder valve on the deethanizer feed line (4'* - P-412) downstream of control valve LCV-402. 35. On the discharge side of demethanizer reflex pump GA-401 provide a 3/4" welded connector and attach a 3/4" stainless steel gate valve. Further, attach a 3/4" flange connection at the outlet side of the valve. (See Basil Drymon for the exact location of the valve.) 36. On the discharge side of the spare demethanizer reflux pump, GA-401S, provide a 3/4" welded connector and attach a 3/4" stainless steel gate valve. Further, attach a 3/4" flange connection at the outlet side of the valve (See Basil Dryman for the exact location of the valve). o'oO' & 0$.90 * WORK LIST REFER TO DWG. NO. LCCP-734-1 1. Install a 3/4" Strahman sampling valve on the 2V product line at the outlet of the debutanizer bottoms cooler* EA-415. 2. Install a sample bomb and valve manifold on a new Unistrut rack near the depropanizer bottoms control valve, LCV-416. A 500 cc. sample bomb having a 1/4" Whitey needle valves will be used. Manifold valves will be Smith type ball valves - 1/4 turn to open. Inlet and outlet valves to bomb will connect to V' pipe quick disconnects (MGM No. 203SS) 3. Run line l/4"-HM-01-P-A2-l from the 3/4" upstream bleeder valve (at LCV-416) to the sample bomb manifold. 4. Run line l/4"-HM-02-P-A2-l from the sample bomb manifold to the 3/4" sample valve (sample point NO. 20) located on the debutanizer feed line (3"-P-497). Remove the other sampling valves located at sampling point No. 20. 5. Run vent line 3/4"-HM-03-P-A2-l from the sample bomb manifold to a new 2" vent collection (V.C.) header, line 2"-HM-21-N-Al3-4-M. The exact location for the tie-in will be specified in a subsequent design. 6. Run line 3/4"-FG-l2-N-B2-1 from an existing 3/4" bleeder valve on the Gillis methane gas line (3/4"-NG-AGA) located near the reflux pumps, GA-409 & S, to the sample bomb manifold. Install a pressure reducing valve PCI-400 in line 3/4"-FG-12 near the tie-in to the sampling mani fold. 7. Remove the existing sample collection manifold for the light aromatics distillate sample and plug the 3/4" sample valve nearest line 3"-P-713. REFER TO DWG. NO. LCCP-734-2 8. Install a 3/4" Strahman sampling valve on the 4" quench water blowdown line at the settler drum. 9. Install a 3/4" Strahman sampling valve on the quench water circulation line (16"-QW-100-A2A) beneath the settler drum. Install valve horizon tal to grade. 10. Install a 3/4" Strahman sampling valve on the 1^" heavy aromatics product line (1V-P-151) downstream of control valve LCV-101. 11. Remove the existing 3/4" sampling valve and plug the 3/4" bleeder valve on the 4" quench water blowdown line. 000010s91 * WORK LIST - Continued - page 2 12. Disconnect the 3/4" sampling line to the quench water sample cooler and plug the 3/4" bleeder valve on line 16"-QW-l00. 13. Remove the 3/4" hose and plug bleeder valve at control valve LCV-101. 14. Remove the 3/4" drain line from the heavy aromatics sampling point and plug valve. REFER TO DWG. NO. LCCP-73A-3 15. Install a 3/4" Strahman sampling valve on a 4" discharge line at the light aromatics transfer pump, P7-911. 16. Remove sample tubing and plug existing sampling valve at the pressure gauge on pump P7-911. 17. Remove the existing 3" hosing at tank T7-901, and blind drain valve. 18. Remove sample tubing and plug 1/4" sample valve located near pressure gauge on tank T7-901. REFER TO DWG. NO. LCCP-734-4 19. Install a sample bomb and valve manifold on a new Unistrut rack near the demethanizer bottoms control valve LCV-402. A 500 cc. sample bcnb having 1/4" Whitey needle valve will be used. Manifold valves will be Smith type ball valves - 1/4 turn to open. Inlet and outlet valves to bomb will connect to V` Pipe quick disconnects fMGM Mo. 203SS). 20. Run line l/4"-HM-04-C-B2-10 from the 3/4" .bleeder valve (at LCV-402) to the sample bomb manifold. 21. Run line l/4"-HM-05-C-B2-10 from the sample bomb manifold to the dethanizer feed line (6"-P412). 22. Run line 3/4"-FG-14-N-A2-1 from an existing 3/4" bleeder on the methane off-gas (M.O.G.) line 4"-P325-A2A to the demethanizer sample bomb manifold. 23. Run vent line 3/4"-HM-06-C-B2-10 from the demethanizer sampling bomb manifold to a new 2" vent collection header, line 2"-HM-20. The exact location for the tie-in will be specified in a subsequent design for vent collection. 24. Install a sample bomb and valve manifold on a Unistrut rack near the deethanizer bottoms control valve, LCV-403. A 500 cc. sample bomb hav ing 1/4" Whitey needle valves will be used. Manifold valves will be Smith type ball valves - 1/4 turn to open. Inlet and outlet valves to bomb will connect to H" pipe quick disconnects (MGM No. 203SS). OOOOl- WORK LIST - Continued - page 3 25. Run line l/4"-HM-07-P-B2-2 from the 3/4" upstream bleeder valve (at LCV-403) to the sample bomb manifold. 26. Run line l/4"-HM-08-P-B2-2 from the sample bomb manifold to the down stream 3/4" bleeder valve at LCV-403. 27. Run line 3/4"-FG-16-N-A2-l from the tie-in with line 3/4"-FG-14 to the deethanizer sample bomb manifold. 28. Run vent line 3/4"-HM-09-P-B2-2 from the sample bomb manifold to a new 2" vent collection header, line 2"-HM-20. The exact location of the tie-in will be specified in a subsequent design for vent collection. REFER TO DWG. NO. LCCP-734-5 29. Install a sample bomb and valve manifold on a Unistrut rack near the sample point No. 9 where the caustic tower overhead sample is presently collected. A 250 cc. sample bomb having 1/4" VJhitey needle valves will be used. Manifold valves will be Smith type ball valves - 1/4 turn to open. Inlet and outlet valves to bomb will connect to V pipe quick disconnects (MGM No. 203SS). 30. Run line l/4"-HM-10-N-B2-2 from the 3/4" sample valve (at sample point No. 9) to the sample bomb manifold. 31. Run line 3/4"-FG-18-N-A2-l from a tie-in with a 3/4" bleeder on the methane off-gas line (4"-P-584) located near the fuel gas drum to the sample bomb manifold. 32. Run a 3/4" vent line (HM-11) from the sample bomb manifold to a new 2" vent collection header, line 2"-HM-20. The exact location of this tie-in will be specified in a subsequent design for vent collection. REFER TO DWG. NO. LCCP-734-6 33. Install four 3/4" Strahman sampling valves on the 3" light aromatic loading lines as shown in the sketch. 34. Remove the existing 3/4" sampling valves and plug pipe connections. MISCELLANEOUS 35. On the discharge side of demethanizer reflux pump GA-401 provide a 3/4" welded connector and attach a 3/4" stainless steel gate valve. Further, attach a 3/4" flange connection at the outlet side of'the valve. (See Basil Drymon for the exact location of the valve.) 000010893 tfCD * WORK LIST - Continued - Page 4 36. On the discharge side of the spare demethanizer reflux pumo, GA-401S* provide a 3/4" welded connector and attach a 3/4" stainless steel gate valve. Further* attach a 3/4" flange connection at the outlet side of the valve (See Basil Dryman for the exact location of the valve). Y\CO * MCI) OOQq PIPING SCHEDULE 3ESICNATT0N *- Flowing Fluid * From ,, j, - SER' riCE To OV-<//'' v'.; /J !/!//./ /;'. vS^j /' SV\rlf///-"&/.) * JV-/ V" . w-'.v " yn ,, /VV.v/ !~`Ja i - o4-C- $2 '/o OtM. -Tt :(v/?a or f:*** S 4> C.\/ 3s. .' \t~c>/:a? /, \'A-V`~ ' f , . .>/!' // AiAf/'/rvAj.* Jv;//;'/,1' JrC-'^d // - '* 3j .C</ -,`v -'. . /.c \Z'4m: / sv * ? '0'- ' '*: '; <' A'.i-J' r-3/3 V# _ ' 1 ri 1 i. 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' v-`y > ^* /Uf' //- ' > / /* J/ f/ // > '/' ^ 1 ' jr /f ., \MX! t1 ' - , . /. t ) o' , '' ' K " f ; ' * .;v' * a n /* Flow Lb./Hr. -- --___ -- -- -- -- -- -- - ~ Phase -- _-- -- -- -- -- -- -- -- -- -- -- -- -- --- -- P5I A?/lO' -- -- -- -- -- __ -- ---- -- - - -- / r>er /j2 . -- 1 iI 1j ,* * rf r, / V .V . ^ -- 7 .'7/ / *>'' .-- / ''.'A . rrr--r / * - ' JV' < . , `.A -'.v> < / 7 . -T. , t r- i.' '' 7 /T" / ->r/A" .vv'- :-//*/ py-T'* ::/ |r |..7- * ,'/ ' ?v> "X? 7,' "* - -- -- 3SCU< Sd __7,,. vV/' ;`7^. r^-.- -: ^7 ' ^.v 7 -'. > //' X-'W V V-?; X jys'. v-m r. K'/y'/-7 C/s/S 'j':-/*'- .' -- - * .'/, - noii 'T' . . - oisd `sco-xa ogt: 0( j: / 0} ;;,'/ >. -- . v i .* //A /7 " vv yr/ /^ . . < . ; 0' - T * dUJcJ, t z/ /> <: OXSd `cs^d ^0 dm d avwuou //-wy/'A.- n 7*. a ..a,.; is 'v"V 7,.jr>v'J -zz9`/V'$r-tWtS- r' :* 4.0-Kv-/r/:^: /'^v (? . V. r//syl }/ sJerzPc/'t-J'W';/'/, p j -, , v'l'1 " ,v fr'/i-tr/v 7^q 5><? ,V'A/, 7 O'/c^-y/y/vJf/ i '< * v o/-z9-0-r. - -;///- /7 "7</, >'(.'< > iK71 -7./. ;tJ --7 . <' v .-./ C- '.{r'_ //f\u'/j/ tt'rtizr -/ //:. ) Y, ^/' ' V'//*. -^ Ap -rz-iv/r-z ,Y s.-'-//. y's -J-V7C7 /^-/--r//xv- OX SOL\U3S mojj //C=r' -7;;// y_ v pmj Su^r.oH l-Y-/-- k"/ p'~/s - 07Z'lS///-nckoliv::ois3 nna?jj;o;j sr' id 9690Tr' 00 a0W hLANT. ENGK'.TCllING OiMTCR PONCA CM Y. Or.LAMOV.A Sf'CCN tCA.UOH >lkCT SKM'-c-!.TAi:.i:n rnKSGU.'t;-; r;-:oui.\to;'.:' , ____ __ pnojccT- APE. NO ______ DATE 1_ MADE livA' f APP`0 OY_________ B. M. NO _______ W 0 NO ________ INO NO___________ nto uo._______ P O NO - 7~j:/s\ Xtc*` No. nr.l Tzt* Service Manufacturer * PC* - c> Pu^c.inc ZaaaA^Z ~>o*a& Mode1 No. 6zt Line Size, Inches -V-- StrcftT. and Valve | riuid Tervp. , F Inlet Presrure, P3I0 Norn-Max. . Outlet Pressure, PSIG Nora-Max. . Seo-22 4*-So Sy. Gr. g?. TaP v ibcob i ty j vs** iu/ ) u p // ?5 : 0.0 fZ -. ' MCD 000010897 ftMMT.. .-2______C.'.,/-3- !'f v____________ / to PI AMT 2 TAG NO. HE V 3 4 5 ^^ 6 . .; 7 -. ' 8 A9 10 11 12 13 14 15 16 17 18 19 20 21 22 1 23 24 25 26 27 28 29 1 30 3i 32 33 34 35 . 36! 37 38 39 40 41 42 43 44 45 46 47 48 49 50 NOTES i. r ENGINEERING CENTER PONCA CITY. OKLAHOMA SPECIFICATION SHEET PRESSURE GAGES QUAN. / -/- / / / / - PROJECT; w DANSE 1 Tube Dial PRESS SERVICE ' r> --V'//_ - A- 1 ! /j; i <j. . r, | :_/l - -------. - c i - r />.:J j 'j- H ft ~'' /_ - i'-1 T - :j ? 1 - C f ' ^ > V ``'D . A F 6 NO_____________________ DATE 1 ~ 4-~:r w g no MAOE BY ^ INQ NO APP D BY REO NO 6 M NO ______ P O NO - /v- ; _'7' ACCESSORIES ------------- ------------- i , . 9* NOTES| 1 ' ,,rN flOOO^^ W~-v INSTRUMENT SOCIETY OF AMERICA . SHFFT . */ j/2- REV -447 L'L'j.L-sCu. Vw' Um%. V'1tl l; b l! Lb 1 \j (b u b b ') Strohman Valves has designee' this new Sampling Valve to produce samples without failure. No settlement or clogging can ever stop this valve from producing a live scmple. This new type Sampling Valve is so constructed that, when in a closed position the stainless steel piston extends to the inner surface of the vessel or pipe, to which it is connected. When this piston is retracted to the open position, a sample is guaranteed because it is impossible for any foreign material 1o gather in the valve, due to the fact that the piston takes up the whole in terior of the valve to itself. This valve is scaled by two Teflon Rings, one above the discharge port and the other below. When necessary, these Rings can be re-compressod against the piston by tightening the packing gland. This new type of seal is much more positive than the old-fashioned disc type. If these Teflon Rings become worn, it is a simple matter to replace them. Shown above ere two Sampling Valves, one in the open position, and, the other closed, illus trating how the piston fills the whole interior of the valve when closed, and, how the piston, when retracted, leaves an entirely empty body for the materia! to pass through. It also illus trates that a minimum of turbulence is created due to the fact that the piston is flush with the inside of the pipe. These Sampling Valves arc made for instciict'cn In existing systems by welding a 34" half coup ling into the pipe or vessel, from which samples are required. They are made with the 34" male pipe thread inlet and Vi" female pipe threcd discharge. To simplify installation in both existing ond pro posed construction it is, therefore, only neces sary to weld a 34" holf coupling at gny spot from which a sample may be required. Matching half couplings furnished on request. FIG. SV-700 hod 0000 10899 : wm z ~;ry:/ r\T--v vi * mis rcvy-ft '-?Vi'V .i I: `* i.\t /;* , oooo aov* 006T *poj;nb9i |i ajqDjioAD UMoqs *d 6ui|dnoa j]oq pajnoiuoa Guiipioy/ 6uj{oj *q| oo?--lHno Pa* ,,Vi *lu! aloul uYt s6u;j oa|oa soitaqso jo uoyaj^ qijM puo |aa;$ s$aju;o|5 9i }o sjjod paj|9M |}o qijM apoyf *6uudpjo uaqM Ajpads asoofj jaqujnfq ajApaips puo azi adij^x uoisuaujiQ :3lON ONHdnoD jivh aaynoiNOD M% i. NOliV'd3dO GNVH aOi DA- A: A? PA-^oT tj?UTANISES* Vv- Vs. MCD 000010902 'Z/ ^ 'o I i Ub cs --J -N Is I .<5 Chkd. by DATE A/* JOB NO.. /v 'G 'T/C /*/ S^fAStr f//* '//^rj.,> A ,*< A. 000010906 MCD /p ^ ir. o/ssgt/zsm__________ C/.OSZO &*>JX.://'AtAjPL///4 5'/&7Z//(S s-pAf^/s/a a. /$//r^o/V- ad/s't'/a/.at^' ^7~ ^.OAZZ/aSG' A?a C/fc &,> Lj^-7-77 >^4.s/- CC/3-734-<Z <^> W'^A'AT ^>/J77" /ZSS'lO'/ES. * &UJT7 /JZ oa SAMPLING PROCEDURE FOR strahman sampling valves Refer to Dwg. No. 734-3, Detail "A" 1. Insert k" tubing to bottom of a 4 oz. bottle. 2. Turn valve handle slowly outward until liquid flows. Fill bottle three-fourths full. 3. Close valve and cap bottle immediately. Avoid breathing vapors and contact of liquid with skin. MCD 000010907 SAMPLING PROCEDURE FOR THE DEPROPANIZER BOTTOMS (LCCP-734-1) (THIS PROCEDURE REQUIRES THAT ALL 1/4" VALVES BE CLOSED BEFORE STARTING) 1. Check that a 500 cc (type ICC-3E-1800) sample bomb is connected in place. 2. Open the 1/4" needle valves (2) on the sample bomb. 3. Open the 1/4" valve on the inlet line to the sample bomb. The pressure will indicate on the inlet gauge (160 psig maximum). 4. Open the 1/4" valve on the outlet line and allow the sample bomb to purge with flow for fifteen seconds. 5. Close the 1/4" needle valves (2) on the sample bomb. 6. Close the 1/4" valve on the inlet line. 7. Close the 1/4" valve on the outlet line. 8. Open 1/4" vent valves (2) on the sample manifold. Check that both pressure gauges depressure to 12 psig. 9. Open the 1/4" Gillis methane purge valves (2). Mote that the pressure rises onthe pressure gauge (50 psig maximum). Purge the sample bomb connection for fifteen seconds. 10. Close the 1/4" Gillis methane purge valves. Note that the pressure gauges depressure to about 12 psig. This is the minimum pressure of the vent collection header. 11. Close the 1/4" vent valves (2). 12. Break union connections and remove the sample bomb. Install a returned sample bomb in its place. This assures the sampling manifold is kept completely closed at all times. 0 0003-0903 p sampling procedure for DEMETHANIZER BOTTOMS AND DEETHANIZER BOTTOMS (LCCP-734-4) (THIS PROCEDURE REQUIRES THAT ALL 1/4" VALVES BE CLOSED BEFORE STARTING) 1. Check that a 500 cc (type ICC-3E-1800) sample bomb is connected in pi ace. 2. Open the 1/4" needle valves (2) on the sample bomb. 3. Open the 1/4" valve on the inlet line to the sample bomb. The pressure will indicate on the inlet gauge. 4. Open the 1/4" valve on the outlet line and allow the sample bomb to purge with flow for fifteen seconds. 5. Close the 1/4" needle valves (2) on the sample bomb. 6. Closethe 1/4" valve on the inlet line. 7. Close the 1/4" valve on the outlet line. 8. Open 1/4" vent valves (2) on the sample manifold. Check that both pressure gauges depressure to 12 psig. 9. Open the 1/4" M.O.G. purge valves (2). Note that the pressure rises on the pressure gauge (100 psig maximum). Purge the sample bomb con nections fifteen seconds. 10. Close the 1/4" M.O.G. purge valves (2). Note that the pressure gauges depressure to about 12 psig. This is the .minimum pressure of the vent collection header. 11. Close the 1/4" vent valves (2). 12. Break union connections and remove sample bomb. Install a returned sample bomb in its place. This assures the system is kept completely closed at all times. o,0O' >' o.VQC\.O,0 & SAMPLING PROCEDURE FOR CAUSTIC TOWER OVERHEAD (LCCP-73*-5) (THIS PROCEDURE REQUIRES THAT ALL 1/4" VALVES BE CLOSED BEFORE STARTING) 1. Check that a 250 cc. (type ICC-3E-1S00) sample bomb is connected in place. Check that the 1/4" vent valve is closed. 2. Open the 1/4" needle valves (2) on the sample bomb. 3. Open the 1/4" inlet valve. Note the pressure indicates on the inlet gauge. 4. Open the 1/4" outlet valve and let the sample bomb purge v/ith flow for fifteen seconds. 5. Close .the 1/4" needle valves (2) on the sample bomb. 6. Close the 1/4" inlet valve. 7. Close the 1/4" outlet valve. 8. Open the 1/4" vent valve on the sample manifold. Check that the pressure gauge depressure to 12 psig pressure. 9. Open the 1/4" M.O.G. purge valves (2). Note that the pressure rises on the pressure gauge (85 psig maximum). Purge the sample bomb con nections fifteen seconds. 10. Close the 1/4" M.O.G. purge valves (2). Note that the pressure gauge depressures to about 12 psig. This is minimum pressure of the vent collection header. 11. Close the 1/4" vent valve. 12. Break union connections and remove the sample bomb. Install a returned sample bomb in place of the filled bomb. This keeps the system com pletely closed at all times. q9 o' *