Optimization Study Of The Energy Consumption System Of The Distillation Column Based On Absorption Heat Pump

Energy conservation has become a priority for sustainable development of the petrochemical industry, the distillation process is the most common and mature of the separation of materials, the energy consumption of the process greatly affects the company’s survival. Combined heat, optimization of operating parameters and heat pump distillation technology are the common technologies of distillation process for energy-saving, but there are some shortcomings, especially in the energy saving effect for the high temperature distillation column that the large temperature difference between overhead and bottoms not ideal, in order to solve the problem, this paper proposes a method of cascade heating a distillation column based on absorption heat pump, and as the depropanizer as an example, the method is optimized for energy saving distillation provides a new idea. Providing a new idea for the optimized of energy saving distillation.1) In order to solving the problems of waste heat emissions from overhead and large energy level does not match in the process of heating materials. This paper provides the process of cascade heating materials based on Absorption Heat Pump, and builds the mathematical model for the new system. In the case of depropanizer which the capacity is 18 million t / a, and using Aspen Plus software for its process simulation.2) Researching factors of distillation process and analyzing the influence on the energy consumption in the rectification column from the key parameters such as the tower reflux ratio, feed temperature and operating pressure, and then make it clear for the direction of optimization and performance improvement for the new system: on the one hand is to reduce the operation of the rectifying column pressure; on the other hand is to improve the feed temperature of the distillation column.3) With the reduction of operating pressure the heat pump evaporation pressure drops; with the increase of feed temperature, heat pump condensing pressure increases. Considering two factors on the performance of heat pump heating coefficient COPh impact, in consumption process steam amount at least as the research target, obtain the best efficiency of the new system conditions.4) In an actual gas fractionation tower process as an example to design energy saving reform project, and through the energy and economy analysis verify the new energy-saving distillation method application value.