柴油加氢装置低温余热的综合利用

Integrated utilization of Low Temperature Waste Heat in Diesel Hydrotreater

炼油厂260万t/a柴油加氢精制装置在扩能改造的同时,进行了低温余热综合利用改造,主要利用除盐水作热媒,将分馏塔顶油气、精制柴油低温位热源用于取代油品罐区的维温蒸汽,为部分装置伴热、办公取暖等。系统投用后,每年可创效益300万元。在应用过程中,因低温热水用户少、回水温度高,存在着热能利用率低等问题,下一步考虑在新建轻烃回收装置制冷系统利用低温热水,以及进一步综合优化加氢装置用能,提高热进料比例实现热联合,以减少低温热能。

Utilization of low temperature waste heat is integrated into the revamping project of the 2.6Mt/a diesel hydrotreating plant, using desalting water as heat medium and replacing the temperature-keeping steam in oil products tank farm with the waste heat sources from fractionators' top oil-gas and hydrotreated diesel for plant heat tracing and office building heating. The utilization can result in a benefit of 3 million yuan per year. In the next revamping, in order to tackle the issues such as low efficient use of heat energy caused by relatively few users of low temperature hot water and high return water temperature, a refrigeration system should be added in the light hydrocarbon recovery unit to further improve energy efficiency in the diesel hydrotreating plant, raise hot feed ratio, realize heat integration and reduce low temperature heat.