| Company under the much starker choices-and graver consequences-in planning,to transformation and upgrading of technology backward synthesis plant,adopting international advanced technology,the construction of using coal as raw materials,production of 600000 tons/year synthetic ammonia and 600000 tons/year ethylene glycol unit,there is a tremendous amount of waste heat generating device,remove the waste heat is needed to ensure safe and efficient operation.This paper is designed for the circulating water system of the supporting device.The circulating water is used in the open circulating water through the economic and technical comparison.The design includes the cooling tower,circulating water pump and pipeline layout,the side filter device,water treatment and monitoring device,and the same driving operation of the system.Package thermal equilibrium statistical through to the project process,into,out of the circulating water by 10?temperature difference design,determine the entire unit circulation of water is 180000 m~3/h,concentration ratio of circulating water control within five times,reduce caused by CL-high on the system of salt corrosion.Because of the wet bulb temperature as high as28.5?in summer,combined with the design institute of design experience,to determine the cooling tower single pylon processing capacity of 5000 m3/h,construction of 38 cooling tower;According to the distribution of water load and cooling medium,the circulating water system is divided into four circulating water stations:1# for air separation,boiler circulating water station,2~#circulating water for gasification,purification,synthesis,refrigeration equipment,3~#circulating water device for glycol dimethyl oxalate,4~#of circulating water for ethylene glycol synthesis,ethylene glycol distillation device?The circulating water pipe diameter is designed according to the velocity of1.5m/s,and the main pipe diameter of the main pipe is not more than 2600mm.Circulating pump using large flow in double suction centrifugal pump,circulating pump according to each system three open a case design,ensure later in the operation process is not caused by a single pump fault system safety accidents such as parking,according to the big and small pump configuration at the same time,large pump,summer to winter running operating pump to achieve energy saving.The lateral filtration is made of shallow sand filtration,and the surrounding water content is 4000m~3/h.The turbidity of the outflow is reduced to 3NTU,and the turbidity of the whole circulating water system is within 10NTU.The water treatment USES the phosphorus free formula to ensure that the total phosphorus is in accordance with the environmental protection standard,and the circulation system is controlled by the instrument interlock to achieve automatic control.The water flushing of circulating water system is carried out before operation,and the welding slag and sundries left in the pipe and cooling tower are removed during the construction period,so as to avoid blocking the heat exchanger and sprinkler head.After washing,chemical cleaning prefilm is carried out on the circulating water system,removing the oil stain on the metal surface and forming a protective film on the metal surface to increase the corrosion resistance of the equipment.This paper absorbs the problems that the company and its counterparts face in the operation of circulating water.By optimizing the empty height of the eliminator,the configuration of the circulating pump,and the automation control,the cooling water tower is solved and the energy consumption of the circulating water system is reduced.This paper is closely combined with the design of the factory,combining the design specification and the actual operation experience of circulating water,which provides valuable experience for the design of circulating water system of coal chemical plant. |
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