Document JNReokVoVj1GZ9wZK619B6J2v

8.V. UNITED GAS CARRIERS ''UNIGAS INTERNATIONAL" 3011 ED Rotterdam, Netherlands flat "Da l*uv" ScJitaOamaMijk 50 Te). (010114,20.33. int. telex: 2469(2425564 (Operations) 2470ajhartering) Cable: UNIGASlf^R- Mr J.F. Pinkman Conoco Chemicals Company P.Q* BOX 2197 Houston/ Texas 77Q01 U.S.A. Cur ref.: HB?ial - 27 42 .Rotterdam, 24th October 1979 1 Dear John, Res Unigas VCM ship vent recovery systems ______Y2HE_ZE_^-.25th_Segtember_i979 ./- Please find enclosed a copy of the piping diagram of our 5000 cbm type vessels. As can be observed, the incondensables can be directed via the strange gas seperator 'into the vapour cross over and from here into the shore vapour return line. During the loading operation on board m.t. Deltagas dated 8th October 1979, the direct type cooling unit was put in operation. It proved, however, that relative shortly after the start-up, the discharge temperature on the compressors became too high, i.e. above the maximum 90C stipulated in the manufacturers manual. Consequently the plant had to be stopped. Afterwards on several occasions the cooling unit was put in service again, however, leading to the same undesired, condition. Only after about 80% of the inconden sables had been evacuated, it became possible to run the compressors on continuous basis with compressor discharge temperatures within the design specifications. Based on information received from the vessel, we have come to the conclusion that the 1" vent pipe from the condensors is apparently not sufficient to handle the relative large volume of incondensables at the beginning of the loading operation. For this reason we will instruct the master of the next vessel, being m.t. Epsilongas, to start loading on the same manner as on board of the recent loading operation of m.t. Deltagas but simultaneously to keep the valve in the vapourline from the cargo tank to the shore vapour return line open. vvc 000019297 2- - UNIGAS INTERNATIONAL' Our ref.: Date: SB/ml 24-10-1979 During the process of loading then to throttle down this valve smoothly over a certain period of time until the moment the 1" ventline can cope with it alone. This method will not give 100% utilization of our vent recovery system but is the best that can be done under the prevailing circumstances. Trust this described procedure will meet the approval of Jim de Bernardi and his staff. Yours sincerely B.V. United Gas Carriers "UNIGAS INTERNATIONAL" Enel. VVC 000019298