The Technology Research Of North Pressure Shallow Cold Device Of Natural Gas Company Of Daqing

North pressure shallow cold device of Natural Gas Company of Daqing is a simple cold propane refrigeration process using cold-light device, which is part of the ethylene raw material projects. It is used in the extrusion of water and natural gas, natural gas recovery and restructuring at the form of liquid hydrocarbon to provide raw materials for ethylene plant at the same time outside the pressurized natural gas transmission。This article focuses on the problems in systems of the North pressure shallow cold device since they has been put into operation in December of 2001. First, Imported gas compressor system is often blocked, and there are also some problems in gas supply, That is, every compressor has only one filter cone. If blocked, the filter can only be cleaned in downtime. So it not only affects the production but also inconvenient to the demolition and cleaning the filter cone. Second, the system pressure drop between gas compressor valve and the compressor is too large, and the original design of the system pressure drop is 0.25MPa, the actual one is 0.45MPa, so the system holds too much pressure. Third, non-glycol system is not running smoothly, so it affects the refrigeration equipments, the production rates of Liquid hydrocarbon and its quality. Fourth, Sewage Control is not up to standard, and this may cause bad impacts on the surrounding environment. The four main problems will affect the operation of devices and operating efficiency. In this article, through research, analysis, accounting of the North pressure shallow cold device, we have proposed a specific rehabilitation programs, and optimized the design and construction of the transformation, and carried out the assessment and evaluation of the effect of the transformation. Through research, analysis, accounting of the North pressure shallow cold device, we solve the problems, improve the parameters of the device control rate and also achieve the goals of the transformation. And we also make the further analysis and discussion about other problems of the North pressure shallow cold device. This provides technical support for the maintenance and the reference of the optimization and the transformation of the same kind of device.