Study On High-salt Waste Water Near Zero Liquid Discharge And Salt Seperation Technology In Coal Chemical Industy

Coal is the main support in the structure of primary energy for our country,the coal chemical industry development prospect is good,and there are still some parts of the technology key points need to be broken through.It is a key technology for coal chemical plant that how to reuse the water efficiently,and how to achieve the coal chemical industry waste water "Near Zero Liquid Discharge" and recourse utilization of high salt waste water.It is also a trend which following the requirements of country environmental department.This topic base on one coal chemical industry enterprise in Ningxia Autonomous Region,the feed water is RO brine water which come from operating waste water " NZLD "system,test and analyze continuously with a series of the pilot,such as softening of pretreatment,separating salt with Nano filtration,removing COD with advanced oxidation unit,getting salt with evaporation crystallization etc..Analyze the composition of crystal salt,and compared with the existing national standard.According to the pilot test results of Ningxia,to do the technical renovation and salt separation design for the coal chemical industry enterprise existing wastewater "NZLD"system.Summarize and analyze status quo data and the problem of Ningxia coal chemical industry enterprise existing "NZLD " system,propose some optimization Suggestions to the existing "NZLD" system operation,combined with the results of pilot experiments,the technical feasibility of transforming the rationality and economy of the salt separation technical renovation were further demonstrated through the implementation using Nano filtration membrane as the key point of salt separation.Meanwhile,in view of the present problems of the existing system and the results of pilot experiments,propose the reasonable technical process routes and detailed equipment list of pretreatment unit,Nano filtration salt separation unit,industrial salt production unit for the salt separation project.And put forward the salt crystals calculate data according to the actual water quality,compare with the related government standard,and make the specification for the coal chemical company,estimate the operation cost and investment analysis,it will be a valuable technical and economical reference for the enterprise when the project get to implement.It is obviously that the Nano Filtration salt separation process is reliable in technology,and suitable in economy,so it's a good reference for the similar coal chemical company.Nano filtration membrane as the key point of high salt "NZLD" technology in the coal chemical industry,will have a broad application prospects,and is helpful to promote the application of salt and resource recovery for coal ehemical industry waste water "NZLD" technology.