Document e7mME1JRxQqG1GVKMxroJb4by

INTERNAL CORRESPONDENCE UC 149- 2 CHEMICALS AND PLASTICS r-j (name] Mr . R. E. O'Bryan ^..cation Texas City Plant Mr- M. E. Eisenhour Mr. J. F. Erdmann Mr. W. A. Mazzolini Mr. F. S. Provenzano Unit Staff P, O. SOX 471, TEXAS Cl TV, TEXAS '7590 March 18, 1977 subject VCM Releases - TACB Letter Bob, From the standpoint of the Suspension PVC production department, I suggest that we reply to the TACB letter of February 14 along these lines. First, as we commented initially about the VCM releases, the electrical supply system to the Suspension PVC unit is being re viewed for ways to improve the already very good reliability. Secondly, I would state that a reaction inhibitor system that can operate independently of electrical power has been installed to "kill" reactions and reduce the need for reactor venting in the event of a power failure. I would not mention plans for installation of a VCM gasholder as we did in reply to the July 16th incident since we do not have approval for this project and the inhibitor system mentioned above will con trol at least to some extent the release of VCM to the atmosphere from a power failure. It would be worthwhile, I think, to mention that we are developing element training guides for operators that will improve responses in the event of emergencies such as loss of electrical power and result in less possibility of VCM release to the atmosphere. Listed below are some of the projects in the Suspension PVC production unit already completed aimed at reducing VCM emissions. I'm not sure that it would be appropriate to mention them in the reply letter to the TACB at this time, but perhaps having them listed would be of some value to you in preparing your letter. UCC 092011 l& Mr. R. E. O'Bryan -2- March 18, 1977 Installed multi point area analyzers and data loggers for determining VCM concentrations in the atmosphere. Purchased additional recovery system pumps and compressors. Completed ff-gas recovery system. Installed double mechanical seals on VCM pumps and compressors Installed a scrubber on VCM recovery system condenser vents. Revised VCM tank car unloading facilities. Revised pump priming lines. Revised decanting of recovered VCM tanks. Altered blowdown tanks to improve resin stripping and reduce emissions. Re-routed vents to absorber unit for recovery of VCM. Implemented new technology to reduce VCM emission from reactor openings. Improved control of flow from reactors to stripping tanks to prevent overpressure releases. Installed new metering to improve control of reaction system and prevent emergency VCM releases. Implemented preventative VCM leak detection procedure. Finally, I think we should ask the TACB for any documentation they might possess indicating that the Texas Episodic Model indeed re presents reality and inform us of the parameters that they used in conjunction with this model. Very truly yours. RLF/st R. L. Frantz UCC 092012 ( OPERATING MANUAL B-AUTOCLAVE AGITATOR MECHANICAL SEAL LIQUID SYSTEM BUILDING 115 SOLVENT VINYL RESINS Written By: J. A. Labenski March 22, 1977 Texas City Plant UCC 092013 97. B-AUTOCLAVE AGITATOR MECHANICAL SEAL LIQUID SYSTEM The purpose of the sealing system on the B-autoclave agitators at Bldg. 115 is to contain any VCM which might escape in the event of a seal failure. This system differs from the existing temporary facilities in that it is equipped with the necessary alarms and backup facilities to ensure minimum VCM exposure to personnel in the event of an emergency. 1 * description OF EQUIPMENT A. North Seal Liquid Tank (It. No. M7N-121T) Storage of ethylene glycol for North autoclaves MAWP - 200 psig at 200F Material of Construction - 304 Storage capacity - 250 gallons Size - 2*6" OD, 7*6" height stainless steel B. South Seal Liquid Tank (It. No. M7N-123T) Identical to North tank. C. Ethylene Glycol Drum Pump The existing drum pump will be used to fill the seal liquid tanks. The maximum output pressure is 200 psig. D. Backup Nitrogen Cylinders In case of blowback nitrogen failure, pressure can be supplied to the system by opening the valves on the compressed nitrogen cylinders. II. OPERATION OF SEAL LIQUID SYSTEM Ethylene glycol is stored in the seal liquid tanks at an operating pressure of approximately 100 psig. The pressure is normally maintained by blowback nitrogen controlled by a back pressure motor valve. If necessary, nitrogen can be supplied to both tanks by compressed nitrogen cyclinders located on the Northwest side of Bldg. 115. The North system will support B-6 through B-10 and the South system will support B-l through B-5 and B-ll. The systems will usually be kept separated but if the situation arises, either can support the entire autoclave building. The system is. operated as a static system, i.e., no circulation. ucc 092014 t. \ B-Autoclave Agitator Mechanical Seal Liquid System 98 . III. UNLOADING THE SEALING LIQUID When the level in the sealing liquid tanks drops below 40 inches, it should be recharged. This is accomplished by performing the following steps: 1) Be sure the top of the ethylene glycol drums are free of debris. 2) Hook up the drum pump to the drum. 3) Set the remote tank level indicator to the tank being filled. (The switch is located inside the control room.) 4) Open the charging line chain valve located on the sealing liquid tank. 5) Pump two drums into the tank. Only full drums will be used to fill the system so that contamination will be minimized. 6) Close the charging line chain valve. NOTE: The system's pressure does not have to be lowered since the tank will automatically maintain its pressure at 125 psig. IV. PERIODIC FLUSH OF AGITATOR SEALS Every Monday, Wednesday, and Friday on Evening shift the drain valve on each individual agitator seal should b'e opened for a few seconds. This must be done very slowly so that the seal will not be unseated. The glycol should be examined for con tamination and excessive nitrogen and any abnormality should be noted in the Bldg. 115 Logbook. V. INSTRUMENTATION AND ALARMS A. Sealing Tank Liquid Level Recorders (2) Records liquid levels in each tank. B. Sealing Tank Low Level Alarms (2) Indicates when either tanks levels drop below 20 inches of water. C. System Low Pressure Alarms (2) Indicates when either systems pressure drops below 90 psig. UCC 092015 B-Autoclave Agitator Mechanical Seal Liquid System 99. D. Remote Liquid Level Indicator Indicates level in either tank, fo. use when filling. E. Sealing Liquid High Flow Alarm Each autoclave is equipped with a high flow alarm which indicates when the combined flow to the autoclave's agitator seals is greater than 3 cc/min. F. Agitator Rotameter Flow Indicators Indicates flow to a specific agitator seal (normally less than 1 cc/min). G. Back Pressure Nitrogen Motor Valves Maintains pressure in each system at 100 psig. H. Sealing Tank Pressure Regulator (2) Each tank is equipped with a regulator that automatically vents the tank when over 125 psig. VI. EMERGENCY PROCEDURES A. System Low Pressure Rapid decrease in pressure usually indicates a loss of blowback nitrogen. If this is verified by checking the nitrogen header pressure, put the alternate pressure system in service. B. High Flow To Autoclaves The seal that is leaking can be identified by the rota meters for that autoclave. The seal should be immediately valved in and the agitator shut off. The autoclave should be transferred as soon as possible and the seal repaired. C. Low Level In Sealing Liquid Tanks Rapid decrease in the tanks liquid level usually signifies a line rupture. After this is verified to be the case, the tank should be isolated and the other system should be used for the entire building. XJCC 092016 B-Autoclave Agitator Mechanical Seal Liquid System VII. SAFETY A. Ethylene Glycol Properties FIRE 100. 1. Physical Properties a. Flash point: 240F (open cup) b. Boiling Point: 197.6C c. Freezing Point: -12.7C d. Color: Water-white liquid e. Solubility in water: completely soluble 2. Special Health Precautions a. Eye Hazard - This material may produce irritation similar to that experienced with liquid hand soap. Wear the usual safety glasses when handling this material. If contact occurs, flush eyes with water. b. Skin Contact - This material may cause minor irritation. Avoid unnecessary or prolonged exposure. Wash affected area with water. c. Breathing - Fumes or vapors may produce irritation similar to that experienced with breathing hair spray. Avoid unnecessary or prolonged exposure. d. Swallowing - Hazardous if swallowed and may cause serious injury if prompt treatment is not applied. In case of accidental swallowing, report to the Medical Department immediately. e* Contaminated Clothing - Remove all contaminated clothing. UCC 092017 B-Autoclave Agitator Mechanical Seal Liquid System 101. 3. Emergency Procedures a. Spillage - Do not sewer this material without proper instructions. It may be harmful to the sewage disposal system. Contact Foreman and E.P. Department. b. Fire - Turn in Fire Alarm - Extinguishing Agents: (1) CC>21 dry chemical, foam, and water (2) Dilution type water is the best extinguishing agent. Use spray nozzles to assist in con trolling the fire. B. Pre-startup Safety Checklist 1. North Seal System Check to see that the following is done. The Bldg. 115 Operator and Chief should initial the specific steps when completed. Chief Operator a. The safety valve on the sealing liquid tank is car sealed open and appears to be in good working order. b. Sealing tank liquid level recorder functional. c. Sealing tank low level alarm functional. d. Systems low pressure alarm functional. e. Remote liquid level indicator functional f. Sealing liquid high flow alarm functional g. Rotameter flow indicators operational and in good condition UCC 092018 B-Autoclave Agitator Mechanical Seal Liquid System r 102. B. (Continued) h. Sealing tank pressure regulator relieves at 125 psig i. All valves in correct position Chief Operator ~~ ~~ 2. South Seal System Check to see that the following is done. The Bldg. 115 Operator and Chief should initial the specific steps when completed. a. The safety valve on the sealing liquid tank is car sealed open and appears to be in good working order . ( b. Sealing tank liquid level recorder functional c. Sealing tank low level alarm functional d. Systems low pressure alarm functional e. Remote L.L. indicator functional f. Sealing liquid high flow alarm functional g. Rotameter flow indicators operational and in good condition ___ h. Sealing tank pressure regulator re lieves at 125 psig i. All valves in correct position VIH. FLOW DIAGRAM See Attachment UCC 092019