塔河一号联合站天然气处理装置参数优化研究

Parameter optimization of natural gas processing plant of Tahe 1#

关键词:  天然气  轻烃回收  膨胀机  参数优化 

Key words:  natural gas  light hydrocarbon recovery  expander  parameter optimization

摘要:

针对塔河一号联合站天然气处理装置的实际情况,以该轻烃回收装置的影响因素敏感性分析及装置参数优化为主要研究内容,运用流程模拟软件建立了相应的工艺模型。选择透平膨胀机膨胀端出口温度、丙烷制冷后温度、低温分离器温度、重接触塔理论塔板数、脱乙烷塔理论塔板数以及脱乙烷塔塔底重沸器温度为主要因素,讨论这些因素对C₃、C⁺₃回收率及装置能耗的影响程度。在此基础上以操作参数为决策变量,以回收率和能耗为优化目标,结合液化石油气质量标准确立相关的约束条件,建立了基于流程模拟和SQP法的天然气处理装置优化模型,将C₃回收率从83.63%提高到96.65%,C₃⁺回收率从92.30%提高到98.43%。同时,液化气中C₃₊C₄摩尔分数增至95%,C₅摩尔分数降至1%左右。 

Abstract:

Aiming at the actual situation of the natural gas processing plant of the Tahe 1#, this paper focused on the research of the sensitive factors that affect the natural gas processing plant and the optimization of the parameters. In this paper, the process simulation software was used to build a model, and the following factors were used to analyze their influences on the recovery of C₃ and C⁺₃ and the energy consumption of the facility. These factors include the outlet temperature from the expansion side of expansion unit, the temperature after propane refrigeration, the temperature of low-temperature separator, the number of theoretical plates of DHX tower and dethanizing tower, the temperature of reboiler at the bottom of dethanizing tower. Based on the variables above, using high recovery rate and low energy consumption as goals, LPG quality standards as constraint conditions, the paper successfully established the optimal model of natural gas processing facility with sequential quadratic programming method. As a result, the recovery rate of C₃ has increased from 83.63% to 96.65% and the recovery rate of C⁺₃ from 92.30% to 98.43%. At the same time, the molar content in the processed liquefied gas of C₃₊C₄ has increased to 95%, and C₅ has decreased about 1%.