燃气式增压机烟气加热三甘醇脱水再生工艺研究

燃气式增压机烟气余热的合理利用有助于降低天然气集输站场能耗。通过现场实测典型增压脱水站内燃气式增压机的烟气参数,评估其烟气余热利用潜力,提出利用增压机烟气加热再生三甘醇的节能改造方案。建立HYSYS模型,分析改造方案的适应性。采用现金流量法,评价改造方案的经济性。研究结果表明:①燃气式增压机烟气火用值为重沸器所需热负荷的11倍,可为三甘醇富液再生提供足够热量；②重沸器温度和三甘醇循环量的变化对增压机烟气利用率的影响较小,在不同运行工况下,改造方案均具有良好的适应性；③改造方案投资回收期随增压脱水站处理规模的增大而缩短,当站场处理规模大于169×10⁴ m³/d时,静动态投资回收期可控制在1年以内,在节能减排的同时可获得显著经济效益。研究成果为气田增压脱水站的节能改造提供了一种新的思路。 

Study on the reutilization of flue gas waste heat from boosters for dehydration and regeneration process of triethylene glycol

Reasonable utilization of flue gas waste heat from boosters is helpful to save energy consumption of natural gas gathering stations. The flue gas parameters of boosters were measured and the potential of flue gas waste heat was assessed in a typical gas booster & dewatering station. Then a new energy-saving reforming scheme of using flue gas waste heat from boosters was put forward to heat triethylene glycol. The adaptability of the new reforming scheme was analyzed through a HYSYS model. The economy of the new reforming scheme was also evaluated by using the cash flow method. The results showed that the flue gas waste heat could provide enough heat for triethylene glycol regeneration because the exergy value of flue gas is 11 times of the thermal load of reboiler. The change of reboiler temperature and triethylene glycol circulation rate has little influence on the utilization rate of flue gas, and the reforming scheme has good adaptability under different operating conditions. The investment payback period of the reforming project is shortened with the increase of the treatment scale of the station. When the treatment scale of gas booster & dewatering station is greater than 169×10⁴ m³/d, the payback period of the investment could be controlled within 1 year. Obviously, the remarkable economic benefits could be obtained while saving energy and reducing emissions. The achievements provide a new perspective for the energy-saving reformations of gas booster & dewatering stations.