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Produce stainless steel cold rolling dewatered sludge is the main object of study, the system of the sludge as a raw material instead of cement raw material preparation, firing a high-quality cement clinker, and contained in F and heavy metals of Cr Ni and other harmful elements can be effectively solid solution, to avoid secondary pollution \Modern testing techniques by means of XRD, SEM, HTM, DTA and EDS, the physical and chemical characteristics of sludge, sludge best with intake and its clinker rate value, course and mineral structure characteristics of high-temperature reaction of clinker, the cement of the The physical and mechanical properties, a comprehensive analysis to explore, and the introduction of the heavy metal sludge ingredients of Cr, Ni and F elements affect the mechanism of focus on curing effect. Mainly the following research: the main component of stainless steel cold-rolled dewatered sludge chemical composition of Portland cement raw materials, sludge particles are homogeneous small, with a good grinding processability and chemical reactivity, which contained F-elements and heavy metals mineralization, a significant role in promoting the right amount of clinker; excessive sludge ash, the calcination system a substantial increase in the amount of high temperature liquid, viscosity reduction, the A mineral nucleation and crystal growth balanced by destruction, the firing temperature range significantly narrowed prone liquidus excessive caking burning of stream phenomenon. Excess of F exist also lead to clinker cooling into low gelling fluoride silicate minerals 3C 3 S the CaF 2 reduce clinker quality. Laboratory studies and pilot study showed that the raw meal sludge the appropriate content of 5% ± 0.5%; corresponding clinker three rate value should be controlled KH: 0.91 ~~ 0.93 SM: 1.9 ~~ 2.1, IM: 1.7 to 1.9; firing temperature can be reduced to 1400 ° C. Clinker sample sludge with intake of 5% and 10% according to the corresponding national standards for toxicity of heavy metals leaching test, Cr, Ni dissolution values ??are far below the limited value of the corresponding national standards showed that the cement clinker on good curing effect of heavy metal elements. Sludge as a partial substitution of raw ingredients, can effectively save the major cement raw materials such as limestone, iron powder, but also play an F, Cr, Ni and other trace elements mineralization effect, reduce the clinker burning temperature, save fuel and reduce emissions . Estimates based on the effect of industrial pilot production, the raw meal sludge ratio of 5% ± 0.5%, with an annual output of 30 million tons of clinker cement plant normally consumes about 2.5 million tons / year of sludge at the current price per year The total cost of raw materials and fuel savings of more than $ 500,000. The above research, by appropriate formulation optimization and adjustment of process control parameters can be successful under the conditions of existing cement technology to achieve optimal use of stainless steel cold rolled dewatering sludge hazardous waste, not only to increase cement production, reduce costs, but also the complete elimination of the sludge may cause secondary pollution \
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