Technological Parameters Optimization Of Natural Gas Shallow Condensing Recovery Unit

The paper researched on a shallow condensing recovery unit and optimized the technological parameters and process with HYSIM. The minimum energy consumption per C3+ is defined as optimization target, The outlet pressure of the compressor driven by expander and the outlet temperature of the evaporator are defined as the optimization variables. The ethane and methane's contents of light hydrocarbon and other equipment's operating parameters requirement are restraint conditions. The optimization model was established. We abandon the general way adopting quality of stable light hydrocarbon as the restraint conditions because the units we study have not fractionating columns. On the basis of simulation of light hydrocarbon recovery technological process with HYSIM, we study the recovery quantities of the target components and energy consumption and energy consumption per C3+ influenced by optimization variables, besides the optimal parameters influenced by compositions of feed gas is discussed. Through technical analysis the technological process is reorganize.The optimization calculating results of different composition feed gases show that the operating pressure should reduce properly when the feed gas is heavy, improving operating pressure properly will result in increasing the recovery rate of light hydrocarbon when the feed gas is light, the optimization target that the minimum energy consumption and the maximum recovery rate of C3+ is achieved. In accordance with lacking of cold energy in the system, the technological process is reorganized, the surplus cold energy of external dry gas is recovered, the recovery rate of C3+notably increased.