Reading guidance：Guidance: it is very difficult for traditional sludge disposal. The investment cost and running cost accounts for very large proportion of total cost. After effective disposal, sludge will cause heavy

      Printing and dyeing waste water holds characteristics of high concentration, high chroma, large water quality and quantity and strong alkaline. Owing to colorant, paste, active agent and alkali agent contained in printing and dyeing sludge, water quality is very complex, which adds difficulties to waste water disposal. At present, printing and dyeing sludge disposal mainly adopts a method which combines biological and physic-chemical method. Active sludge method is widely applied to sludge disposal. However, a great amount of residual sludge will be produced by using active sludge to dispose printing and dyeing waste water. it is very difficult for traditional sludge disposal. The investment cost and running cost accounts for very large proportion of total cost. After effective disposal, sludge will cause heavy burden for sewage disposal. At present, printing and dyeing sludge is disposed by sanitary landfill, incineration, land use and other disposal methods. But, these methods hold some shortcomes. Therefore, analyze its characteritics and choose proper disposal plans.
Sanitary landfill
     it is shown at some relevant reports that in developed countries, about 38% printing and dyeing sludge adopts sanitary landfill. Owing to simple operation, low cost, china also adopts landfill method. But, landfill always occupy too much land. What’s more, toxic matters contained in sludge may pollute underground water without proper disposal method and produce secondary pollution.
Incineration
     In developed countries, about 10.5% printing and dyeing sludge is disposed by incineration method. The advantage of incineration lying in that it can rapidly reduce the volume of sludge, which is very important for lack of land resources. However, the organic matter contained in our country’s sludge is relatively low. if we choose incineration method, a great amount of energy will be needed. Then, the running cost will be very high and lots of waste gas will be produced. Secondary pollution will be caused without proper strict disposal.
Land utilization
     Land utilization is one of most widely used disposal method for printing and dyeing sludge. Residual sludge contains much rich organic matters and nutrient elements. At the same time, there are lots of micro elements which are beneficial for the growth of plants. Therefore, used as fertilizer for farms or gardens, sludge can not only improve soil structure, but also can provide nutrients. Land utilization accounts for large proportion in developed countries. In china, this job is started early. Because dyestuff, slurry and auxiliary agents are needed in printing and dyeing process. There are some heavy metals, virus and neophyte contained in residual sludge after biological disposal. If sludge with high-content heavy metals is applied to farm land, it will be passed by through food chain and biological chain and do harm to people’s health. In order to control side effects of heavy metals contained in sludge, research on sludge feature, condition and limits are necessary.
     In order to fulfill reduction and dehydration of sludge, printing and dyeing sludge must be treated as well as disposed. Zhengzhou Taida drying equipment co,. Ltd holds rich experience on sludge disposal. Our company has many successful cases on sludge disposal. we are a professional company. Expect your visiting to our company.
 

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