Ethylene Plant Cold Zone Separating System Research Of Factors Affecting The Yield Of Ethylene

Scientific research and industrial development of the petrochemical industry for the production of ethylene and ethylene separation process a higher level demands new petrochemical ethylene production technology is the core technology is the core of the device ethylene petrochemical ethylene yield of ethylene one of the important means of economic and technical indicators, the pursuit of high ethylene yield, improving economic efficiency is the common goal ethylene plant. Ethylene plant separation device, ethylene recovery level has a great impact on the economic benefits of the factory, which is to evaluate whether separation technology and equipment advanced technology is an important economic indicator. Ethylene loss of ethylene recovery separation system of the entire apparatus has a greater impact. This paper introduces the development status of the ethylene industry, the production process of the ethylene plant are described. In combination with the actual ethylene production practices and equipment technical data, analysis of several factors mainly ethylene yield of ethylene separation cold zone system impact analysis focuses on the China PetroChina Lanzhou Petrochemical Company460kt/a ethylene unit area system of separation of cold production technology and process, discusses the main factors ethylene vinyl cryogenic separation system affect the yield of the separation zone demethanizer cold, cold box, methane expansion/ethylene refrigerant compressor and then, propylene refrigerant and deethanizer and ethylene fractionator of the reasons for the loss of ethylene in the detailed analysis and to explore issues key to demethanizer main factors and problems are discussed, elaborated and ethylene demethanizer operating conditions and the cold box data analysis and comparison, made the difference between the temperature of the cold box and design of the actual heat value exists, and focused analysis shows that the cause of higher ethylene loss. Cryogenic separation apparatus, it is necessary at low temperatures below-90℃ethylene and hydrogen and methane separation, freeze-power means about50%of full power freezing, which is the effect of seriously affecting the operation of the product the purity and the subsequent separation step, it is crucial cracked gas separation. In the ethylene plant separation system, through the exhaust demethanizer and cold box separated the largest proportion of the loss of ethylene, ethylene exhaust&loss account for about75of the total loss of the ethylene separation system is to reduce the loss of ethylene and reducing separation system the focus. Ethylene Plant cold zone separating ethylene loss cryogenic separation system cold box outlet exhaust ethylene loss in total separation system the highest proportion of the exhaust outlet ethylene content ethylene plant is about1650ppm, about90%was from the demethanizer overhead lost in the exhaust. By reducing the feed temperature demethanizer overhead, and an appropriate increase in pressure, the exhaust demethanizer overhead ethylene loss was reduced350ppm, reducing the amount of ethylene loss107.3t/a.