延迟焦化放空塔顶空冷器防冻凝措施的探讨

Study on anti-freezing measures for the delayed coking venting tower

对中国石油乌鲁木齐石化公司1.20 Mt/a延迟焦化装置放空塔顶空冷器冬季运行期间频繁发生冻凝的问题及危害进行了分析。采取了以下优化和整改措施:(1)空冷风机采用反转方式运行,解决了蒸汽加热盘管水击问题;(2)将蒸汽加热盘管改为柴油加热盘管,解决了蒸汽加热盘管水击问题,每个冬季节约蒸汽约80 kt,有效地利用了低温热能;(3)利用焦炭塔冷焦后空余时间将空冷器的某单组切出,进行柴油冲洗或蒸汽吹扫,减轻了空冷器管束出现挂蜡、焦粉堵塞问题;(4)根据气温,切出部分空冷器,加大了空冷器管束中的介质流量,降低了管束发生偏流和堵塞的几率,每个冬季可节电约6.15×10~5kW·h。采取上述措施后,空冷器冻凝和堵塞问题基本得到解决。

The problems and hazards which occur frequently in winter freezing during the operation of a1. 20 MM TPY delayed coking unit＇s vent tower overhead air cooler in the refinery of Urumqi Petrochemical Co. are analyzed. The following measures have been adopted to effectively solve the problems.（ 1） adjusting the rotation direction of the air cooler to solve the water hammer problems of heating tubes.（ 2） the heat source of air cooling coils is changed from steam to diesel to solve the problem of water hammer of steam heating tubes. About 80,000 tons of steam is saved in each winter,and the low-temperature heat is effectively utilized.（ 3） the free time of coker column is utilized to switch over the operation of air cooler train so as to implement diesel flushing or steam flushing. All these have reduced the coking and coke plugging problems.（ 4）Based upon the ambient temperature,some air coolers are cut off and the flowrate in the tubes of air coolers is increased to reduce the deflected flow and plugging of tubes,and 6. 15 × 10~5 kW · hr of electricity can be saved each winter.