上海天然气处理厂C3回收工艺优化研究

Optimization research on C3 recovery process of Shanghai natural gas processing plant

关键词:  天然气  C₃收率  热负荷  HYSYS  工艺优化 

Key words:  natural gas  C₃ yield  heat duty  HYSYS  process optimization

摘要:

利用HYSYS模拟软件对上海天然气处理厂C₃回收工艺进行优化。在不同压力下考察了B物流去冷箱比例、脱甲烷塔塔底再沸器热负荷、丙烷制冷负荷对C₃收率及能耗的影响,优化了工艺条件。结果 表明,在进气温度为20 ℃、处理量为100×10⁴ m³/d的工况下,压力为4 500 kPa时,应关闭B物流旁通,降低脱甲烷塔再沸器热负荷至125.98 kW。此时,C₃收率可提高至97.4%左右；压力为4 000 kPa时,B物流旁通应全部关闭,适宜的脱甲烷塔再沸器的热负荷为61 kW。此时,C₃收率为90.2%左右；当压力降至3 600 kPa时,B物流旁通应全部关闭,适宜的脱甲烷塔再沸器的热负荷为55 kW,丙烷机制冷负荷为33%。此时,系统C₃收率可达到81.56%左右。 

Abstract:

The C₃ recovery process of Shanghai natural gas processing plant was optimized by using HYSYS software. The effects of the proportion of feed B to the chiller, heat load of demethanizer reboiler and refrigeration load of propane compressor on C₃ yield were systematically studied under different pressure. The results show that when the feed gas temperature is 20 ℃, processing capacity is 1 000×10³ m³/d, and pressure is 4 500 kPa, the by-pass valve of feed B should be closed completely, and the heat load of demethanizer reboiler is reduced to 125.98 kW,thereby the yield of C₃ is up to about 97.4%；when the pressure is 4 000 kPa, by-pass valve of feed B should be closed completely, suitable heat load of demethanizer reboiler is 61 kW,thus, the C₃ yield reaches about 90.2%; when the pressure is 3 600 kPa, the suitable heat load of demethanizer reboiler is 55 kW,by-pass valve of feed B should be closed completely too, the refrigeration load of propane compressor is 33%, and the C₃ yield is about 81.56%.