Since the dilution steam replenishing generator EH-235A~E is currently unable to produce a large amount of dilution steam, the large amount of dilution steam required for the cracking furnace can only be directly supplemented by the outside, and the replenishing amount is about 38t/h or more, and the result is a large amount of Process water is wasted. The quenching oil visbreaking system cannot be used in the original design. The quenching oil visbreaking system has serious environmental problems and cannot be used. As a result, the quenching oil is difficult to reduce viscosity. At present, the system can only be operated by increasing the tempering oil and lowering the temperature of the tower. Because the viscosity of the quenching oil is too high, it affects the amount of dilution steam generated by the quenching oil, and is also one of the reasons why the amount of dilution steam of the quenching oil is too small. Because the viscosity of the quenching oil is too high, the system takes too little heat, which directly causes the high temperature heat of the quenching oil to enter the upper part of the quenching oil tower from the lower part of the quenching oil tower, thereby causing heat to enter the quenching water from the upper part of the quenching oil tower, and losing high temperature energy. The main reason for the excessive reflux of gasoline in the quenching tower (gasoline reflux) is that the heat in the lower part of the quenching tower is too high, and it is forced to increase the reflux of the gasoline. On the one hand, the high temperature heat energy is lost, and on the other hand, the quench water is emulsified due to excessive heavy oil. The low temperature of the quenching water is too high. Because the gasoline reflux of the quenching tower is too large, a large amount of heat enters the quenching tower to become a low-temperature heat source, causing too much heat in the quenching tower, causing the quenching tower air cooler to be seriously overloaded. The summer air cooler was forced to water and cool down, causing a lot of water waste and heat loss. Ethylene quenching system technology can not adapt to new conditions. Ethylene plant quenching system technology has always been highly valued by various ethylene manufacturers. In order to create a better operating environment and conditions, many manufacturers have carried out many transformations, such as Yanshan and Yangzi Company. The quenching system was rebuilt three times, and Qilu Company carried out four transformations on the quenching system, with the aim of applying advanced technology. Due to the early construction of the 330kt/a ethylene of Daqing Petrochemical Company, the process environment has undergone great changes. If the raw material becomes heavier, the temperature of the light hydrocarbon gasification increases; the process technology of the diluted steam generation system is backward; the environmental protection standard is improved. At present, ethylene refrigeration system technology has been unable to adapt to the new conditions. Cracking gas compressors have low efficiency. The cracking gas compressors have two main reasons for low efficiency. (1) Severe fouling; (2) Excessive backflow between sections. See the operating parameters of the cracking gas compressor, see the turbine operating parameters of the cracking gas compressor. Design actual dilution steam generation / (th-1) 56451.0MPa supplementary steam consumption / (th-1) 6354 external introduction 1.0MPa steam direct dilution steam amount / (th-1) 2.638 supplementary generator EH-235A ~ E1. 0MPa steam consumption design and actual design design actual dilution steam generation / (th-1) 292.7 quench oil volume / (th-1) 966770 quench oil heat exchanger inlet and outlet temperature difference Δt / ° C31.43.5 quench oil dilution steam generator EH-234A/B design parameters and actual parameters comparison cracking gas compressor operating parameters propylene refrigeration compressor design discharge pressure is too low design propylene refrigeration compressor discharge pressure is 17.8MPa, corresponding condensing temperature is 45 ° C, compressor discharge propylene The air condenser was condensed, and the atmospheric temperature of the air condenser was designed to be calculated at 32 °C. Since the atmospheric temperature in the summer often exceeds 32 ° C, the discharge pressure of the propylene compressor causes the compressor discharge pressure to be too high due to insufficient air condenser capacity, and is forced to water the air condenser to cool and condense, thereby wasting a large amount of water. Unreasonable public works support Due to the above-mentioned problems in the old area, some low-pressure grade steam generation is too large to be utilized. For example, 0.3MPa and 0.1MPa steam generation is too large to be utilized. The 1.0MPa grade steam is too large, causing unnecessary waste. Since the steam cannot be balanced, it is necessary to decompress 4.0 MPa steam into 1.0 MPa steam, resulting in great waste of energy. Improvement measures to retrofit the quenching oil tower The quenching oil tower problem of the ethylene plant is the main problem affecting the excessive energy consumption of the ethylene plant, so it must be reformed. The transformation is mainly carried out in the following four aspects. (1) The quenching oil circulation system is improved to enable it to establish a stable heat extraction system, increase the heat taken at the high temperature, thereby reducing the gasoline return flow, correspondingly reducing the top discharge temperature, and establishing a reasonable quenching oil heat extraction process. . (2) Renovation of the visbreaking system to achieve controllable viscosity of the quench oil system, reduce the amount of tempering oil, and create conditions for more heat taking. The quenching oil system viscosity technology is currently mature and reliable. (3) Optimize the process of dilute steam generation system. Under the high-quality quenching oil and its viscosity process, a reliable dilution steam generation process is adopted. The quenching oil is used to generate more heat, reduce the steam consumption by 1.0MPa, and reduce the steam generation by 0.3MPa. . The dilute steam generation system process can adopt a new and reliable process to reduce the amount of dilution steam caused by the leakage of quench oil from the quench oil heat exchanger, to ensure that the 1.0 MPa steam dilution steam system is reliable, and to reduce the quench water discharge. (4) Adjust the heat exchange process of the quenching oil, reduce the exhaust temperature of some cracking furnaces, and improve the thermal efficiency of the cracking furnace. The cycle between compressor sections can be greatly reduced after the reformation of the quench oil system. The composition of the circulating materials between the compressor sections will also be improved, which will be beneficial to reduce compressor fouling and improve compressor efficiency. Other system transformation (1) The refining system is cooled by a new process to recover the expansion/compressor. The power supply per h can be about 250kW, which is equivalent to saving 1.0MPa steam 2t/h. (2) The rectification system is cooled by a new process. The temperature of the methane column, which reduces the ethylene content in methane, can increase the ethylene yield by about 0.2% or more. The technology is simple and reliable. (3) Improve the heat exchange process of the quench water system, and maximize the output of low-temperature heat, which can save 0.3MPa steam. (4) The post-separation system uses a new process to save a large amount of 4.0 MPa steam and 1.0 MPa steam. (5) Optimization of process flow of propylene refrigeration compressor. The introduction of ultra-high-pressure ethylene to reduce the load on the propylene machine by 14% and reduce the watering of the propylene refrigeration compressor during the summer season. Concluding remarks (1) The 15% energy saving goal of the 330kt/a ethylene plant of Daqing Petrochemical Company can be realized after the completion of the transformation of the ethylene plant. (2) The modification of the ethylene plant can be carried out during the overhaul of the device. Mechanical Parts,Hardware Processing,Mold Guiding Rod Set,Mold Guiding Rod Set Making Guangdong Rixin Precision Technology Co., Ltd. , https://www.nissontooling.com