Reading guidance：Textile printing and dyeing industry prospers in shaoxing, zhejiang province. At the same time, this industry has produced a lot of printing and dyeing sewage. In the process of disposing printing and

 Textile printing and dyeing industry prospers in shaoxing, zhejiang province. At the same time, this industry has produced a lot of printing and dyeing sewage. In the process of disposing printing and dyeing sewage, sludge which contains dyestuff and textile thread. Owing to the complexity of dyestuff, the composition of sludge is very complex. If the printing and dyeing sludge is buried directly, pollution to environment will be caused, which can be presented in sludge discharge events. Therefore, printing and dyeing sludge should be disposed effectively. At present, relevant experts conclude reclamation technology of sludge: use for building materials.
Composition in printing and dyeing sludge mainly come from residual dyestuff, slurry, assistant, oil solution, fiber impurity and sand matter. The loss of burn is pretty high (can reach to over 50%). The thermal value of printing and dyeing sludge is high (can reach to 2024.8 k cal). As a result, printing and dyeing sludge is suitable for producing environmental protection sintering brick, light ceramic particles and other building raw materials.
Therefore, the components in printing and dyeing sludge are not only suitable for building materials, but also can be used as replacement for clay in order to match with coal flyash, gangue and other materials and produce energy-saving bricks, environmental protection bricks and light ceramic particles. In the firing process of sludge utilization, it contains organic matter which can provide heat of the heat of the high temperature roasting, the brick kiln sintering and sintering ceramsite produced when heat, drying pretreatment of tile and ceramic, so as to greatly reduce the production costs, to achieve the requirements of resources. In addition, through the high temperature roasting, can kill the sludge of pathogens, also curing heavy metal material, in line with the "harmless". So the use of textile dyeing sludge development building materials use is a very advantage of sludge disposal technology.
Apply dyeing sludge to make environmental protection brick
   Main process of textile dyeing sludge brick and brick are basically the same, the main difference lies in the preparation process of sludge. General Sinotrans disposal of sludge water rate reached more than 80%, much higher than ordinary sintering brick raw material (shale, coal gangue, fly ash, etc.). Due to the production process of tile water rate is not more than 23%, and the sludge with high water content became the sludge for brick making process of a big problem.
   To solve this problem by adjusting the sludge blending ratio and control the moisture content of sludge, mainly as follows: (1) directly incorporated against: the method of the sludge (moisture content 80%) directly and other raw materials mix against the mixing. Process is relatively simple, no need to increase the sludge dehydration and drying equipment, reduce the cost of investment. However, the amount of sludge mixed with less, according to the volume ratio of up to 15% (water content 80%). According to an annual output of 100 million brick production lines, for example, only 70 m3 (water content 80%) per day can be mixed with the sludge. (2) after the dehydration of blending: the method using filter press dehydration, flue gas drying and other measures, sludge dehydration to a certain moisture content, and other raw materials mix against the stirring. The sludge blending quantity, for example to filter will sludge pressing water rate of mud below 60%, crushing and other raw material mix ratio can reach 25% (including 60% water), the sludge moisture content 80%) handling capacity is equivalent to 3 times the direct blending method. If roasting flue gas as a heat source for drying, in dehydration by drying sludge will be the basis to containing 30% water, the sludge content than even up to 50%, the sludge moisture content 80%) processing capacity is equivalent to 12 times the direct blending method, and due to the recycling of the waste heat and saves the cost. (3) after incineration blending: the method that will handle the sludge incineration, and the ash as brick making raw materials. After incineration of sludge mixing ratio is no longer restricted by the water content, and also can be used as reducing the water content of the sludge conditioner. Because of the basic removal of organic matter, the production process does not produce odor, to protect the health of the first line workers. However, because the calorific value of the sludge is basically zero, it can not provide the heating value of the sintering process. In addition, burning equipment investment, high operating costs, and alone to make bricks and ancillary equipment burning equipment is not economical.
Apply dyeing sludge to make ceramic particles
  At present mainly in the rotary kiln production of lightweight aggregate, kiln outside into ball and kiln into spheres of the two process routes. Outside the kiln balling is using a ball on disc granulation equipment, the first raw material of a certain size globular state, and then into the rotary kiln roasting. Kiln into a ball can make production ceramsite with controllable size, due to the material into the granulation equipment moisture content must be less than 25%, so outside the kiln into ball technology is also facing the sludge moisture content is a problem, but also the need to take into account the sludge dehydration, drying and mixing ratio and other factors, resulting in the process of complex and increase the cost of the investment.
   In the kiln, the ball is designed to be in the rotary kiln, and the material is rolled into a ball by rotating the rotary kiln. The water content of the kiln is lower, and the material of the 70% water content can be directly put into the kiln. Therefore sludge as long as through a certain mixing ratio, Chen of process, eliminating the dehydration, drying and other processes, greatly simplifies the process, saves the cost of investment. But the ball into the ball of the product size is not controllable, and mainly to ceramic sand, coupled with high water content of the material is easy to cause the material conveyor belt of the card dead, need to manually handle, affect the automation process. Therefore, in the selection process, not only need to consider the needs of products and investment funds, etc., but also need to analyze the impact of sludge mixing on the entire process, combined with the existing conditions to consider.
   The production of lightweight aggregate in rotary kiln, especially in the process of production of the ball in the kiln, the difference of grain size is great. For not sold products and defective products, should be re used in the production of other products, such as lightweight baking free brick aggregate and so on.
   Textile dyeing sludge if discharged directly to the external environment will cause the problem of environmental pollution, printing and dyeing sludge after treatment of harmless, stabilization, to find resource disposal way, will produce certain environmental benefits and social benefits.
 
 

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