基于RSM的天然气脱硫脱碳装置适应性建模及分析

Establishment and analysis for adaptive model of natural gas desulfurization and decarburization facilities based on RSM

关键词:  脱硫  脱碳  气质变化  适应性  RSM  H₂S  CO₂ 

Key words:  desulfurization  decarburization  variation of feed gas composition  adaptability  RSM  H₂S  CO₂

摘要:

原料气条件发生变化后,天然气脱硫脱碳装置常出现运行不稳定、酸性组分过度分离等问题。采用模拟软件建立某脱硫脱碳装置工艺模型,选择原料气处理量、CO₂体积分数作为原料气条件变化参数,DEA质量分数、贫液进料位置、循环量和装置能耗作为适应性参数。基于RSM建立试验方案,回归得到装置适应性模型。对模型进行分析,结果表明,处理量和CO₂体积分数上升将导致装置循环量和能耗上升,相对于处理量而言,CO₂体积分数影响程度更大；提高进料位置和DEA质量分数均有助于降低溶液循环量及装置能耗,进料位置对装置的影响略大于DEA质量分数的影响；处理量和CO₂体积分数对循环量和装置能耗的影响表现出强烈的交互作用；调节DEA质量分数与进料位置,可以有效地减小原料气条件变化对装置的影响。 

Abstract:

The desulfurization and decarburization devices operate unstably and acidic components are separated excessively when it comes to variation of feed gas conditions. Process model of a desulfurization and decarburization device was established using simulation software and the adaptive model was regressed on the base of RSM. Volume flow rate of feed gas, CO₂ volume fraction as the varying parameters of feed gas conditions and DEA mass fraction, location of lean amine into absorber, amine circulation volume rate and energy consumption of the unit were chosen as adaptive variable. Based on the analysis of the model,the results were showed as follows:The increase of processing capacity and CO₂ volume fraction will lead to the increase of amine circulation volume rate and energy consumption. Compared with processing capacity, CO₂ volume fraction has more influence on the amine circulation volume rate and energy consumption. Rising the location into absorber and increasing DEA mass fraction will both contribute to the decrease of amine circulation volume rate and energy consumption, and the former has slightly more influence than the latter. There is a strong interaction between the processing capacity and CO₂ volume fraction on affecting the amine circulation volume rate and energy consumption. The last but not the least, it can be regarded as an efficient way to reduce the influence brought by the variation of feed gas conditions to regulate DEA mass fraction and location of lean amine into absorber.