Study On Process Flow Of Olefin Separation Unit

In the period of the Twelfth Five-Year Plan,methanol to olefins technology will be moderately developed in our country,which will be an important supplement to the production of olefins by traditional technology.The methanol to olefins industry needs to be improved and optimized on the basis of existing technology,so as to further improve the competitiveness of the technology.The methanol to olefin unit includes the reactionregeneration part and the olefin separation part of the reaction gas.The reaction regeneration part is the main demonstration point of the existing plant,but the energy consumption of the olefin separation section is two thirds of the whole device.The optimization of olefin separation process is of great significance for energy saving and technical upgrading of methanol to olefins unit.This paper mainly studied the methanol to olefins plant production technology and the characteristics of the separation process,compares the advantages and disadvantages of different technological process and analysis,describes the domestic first set of methanol to olefins device-shenhua baotou company olefin separation plant process principle,technological process,elaborated the problems that exist in the set of devices in the production operation process,this article mainly aims at influence the facility construction,production smooth running of the three problems are studied,mainly including: propylene product protection bed regeneration and breakdown maintenance propylene loses much;propylene loss in propylene refrigeration compressor is large;nitrogen cannot be recovered during the heating process of the reactor.After analysis research ultimately determines the technical retrofit scheme,at the same time transformation content in shenhua yulin company olefin separation device has been successful validation: add propylene bed protection vaporization process,evaporation condensation propylene adsorbent propylene,residual reducing propylene loss;the main sealing gas of propylene refrigeration compressor has been added to the gas phase propylene,and the low pressure nitrogen is not used in the construction process to prevent the low pressure nitrogen from entering the process system.nitrogen closed-circuit circulation is established by using the product gas compressor of the olefin separation device,so that the introduced hot nitrogen can be recycled and continuously heated for the reactor,instead of discharging directly.by process optimization of olefin separation device to solve the constrained device security,economic,smooth running,for olefin separation plant process optimizing made an important contribution to the development of the subsequent process for olefin separation device package design provides important technical support.