Document zdm7M3KjBR9JdqKX9Gadkvp4n

Tenneco Chemicals, Inc. (COMPANY) (DRO-6-79) INTEROFFICE COMMUNICATIO! TO: . E. Richter DATE: March 9, 1979 FOR: Distribution FROM; D. R. Oakley RE: Reactor Discharge Procedure Recently, a great deal of attention has been given to insuring that no resin is left in the reactor following a discharge, Les Roberts has provided the following information, based on experience, regarding the best procedure for insuring a thorough washout. 1. The reactor agitator should be stopped shortly after the slurry level drops below the bottom blade, 2. The water wash orbijets should be started down as soon as the agitator stops. This will mean that the nuclear level switch, ON-LSL-242, will not see an empty discharge leg until after completion of the wash. 3. The temperature of the reactor walls is critical to OC coating effectiveness. Based on this information, the following modifications to the reactor discharge procedures seem desirable, 1. The reactor agitator should be turned off only on RPM's and not on the status of ON-LSL-242 or elapsed discharge time, as is currently done. Agitator RFM is probably a more accurate measure of reactor level than either of the other two methods. This does present a problem, however, in deciding (by an algorithm) when discharge is complete and when PREP should begin. Ideally, the level devices should be able to detect the difference between slurry and water although some adjustments will be required. 2. Cooling of the reactor walls should begin as soon as ON-AV-68 is opened. Currently, if ON-LSL-242 is malfunctioning at the beginning of discharge, the cooling step may be skipped altogether. 3. It would be desirable to leave UV-61,63,233 and 12-PV-91 open during the prep procedure to avoid a vacuum on the reactor. This has a potential safety problem, since the slop tanks would be separated from a high pressure system by the 62 valves only. Preliminary revisions are attached. DRO/cjm Attachments cc: L. C. Elliott - w/attachments C. S. Srutts T,. L. Roberts TEN 1415