Texaco煤气化灰水处理功量交换应用分析

Analysis of applying work exchange in grey water treatment of Texaco gasification

Texaco煤气化灰水处理工艺过程耗能巨大,该过程涉及到灰水温度、压力等参数的大幅度变化,蕴含着大量的可回收机械能。功量交换可实现高压流体向低压流体压力能的传递,提供了一种系统能量综合与集成的新手段。对现有工艺中蕴含的可回收机械能做了简要计算,进行了比分析。结果表明:对于一个30万t/a合成氨的煤化工企业,Texaco煤气化灰水处理过程高压流体的可回收能量达5.1 kJ/kg,功量交换过程比效率达到了20.9%,所节省的设备投资达700万元,年节约能耗2.16×106 kW.h,节约电费112万元。对这一应用方案中的设备问题提出了设置增压泵、适当设备选型等解决方案。从而可以看出,功量交换在煤气化灰水处理工艺中具有很大的应用潜力。

As involving great variation of water temperature and pressure parameters, the grey water treatment of Texaco gasification is a process with great energy cost, and contains lots of recyclable mechanical energy. Work exchanger can transfer pressure energy from high-pressure fluid to low-pressure fluid, thus providing a new way to carry out energy integration and synthesis. A brief calculation on energy recovery and specific exergy analysis of gasification process was made. The result shows that for a coal chemical plant with ammonia capacity of 300 000 t/a, the recyclable energy from the high pressure fluid in the grey water treatment of Texaco gasification can reach as much as 5. 1 kJ/kg, and the work exchanger can reach a specific exergy efficiency up to 20. 9%, with the corresponding equipment cost saving of 7 million yuan, and an energy saving of 2.16 ×10^6kW· h or equivalent to the power cost of 1.12 million yuan. Some suggestions like adding booster pump and proper equipment selection were proposed to solve the problem in the application. Work exchange has great potential in the grey-water treatment of coal gasification.