| Large of resources and energy have to be used up for about 1000 million tons cement production every year in China, which results in the serious problem about how to develop continually. To result this question, one of effective techniques is to utilize the industrial solid waste as cement admixture or cementitious with special function, which reduces not only consumes of resources and energy, but also industry pollutions else. The shortcomings of Portland cement itself can be resulted by utilizing characteristic of industrial solid waste as while as. Funded by the national 863 project, The key Techniques for Preparation of Low Environment Burthen Type of Cement and Cementitious, high calcium ash (HF) are used to produce series low environment burthen type of 42.5 P.O HF blend cement (HBC) and cementitious with special performance. Workability and durability are studied in this paper.Study results of HF characteristic show that the content of coarse grain is 4 times higher than that of fine grain, loss on ignition in coarse grain is 2 times higher than that in fine grain, the content of CaO in coarse grain is 25% less than that in thin grain, HF prolongs the setting time obviously and blend cement with 50% HF shows abnormally setting, expect high f-CaO and instability of content.Unite activating step (UA), including of calcined phosphor gypsum (CG), dry-process calcium carbide sludge (CS), composite chemical active agent NF and milling, is developed to active HF (AF) and improve the soundness. Soundness addition and max addition of 42.5P.C increase from 20%HF to 50%AF. The chemical activating mechanism of UA is that CG can stimulate pozzolanicity more effective than gypsum because of higher solubility and looser crystal structure; but CG has poor property on retardation setting, and this shortage can be solved by mixing with gypsum; CS can offer alkali activity, which can depolymerize silica and aluminum glass, and benefit for other activity methods and overcome the disadvantage of HF on setting time; Sodium sulfate improves early strength greatly but loses the final strength. NF can improve both early and final strengths. The physical mechanism of UA is that activity increases and hazardiess decreases when both of CaO and C are grineded and spreaded around.The model concept of the most compactly pile, closed to hydration degree, is brought forward first time. Basing on Stovall model, the most compactly pile model, which adapts to the designing grain of blend cement, is calculated by ways of thinking over the water film. According to the hydration sequence theory, technique and theory how to produce HBC are developed through the investigation of the hydrating rule of minerals respectively and cooperation with HF.Utilizing UA and theory study result, 2000 million tones HBC and 20 thousand tones AF are industrial produced. Activity index of AF is equal to that of S95 slag. Without strength loss, AF is carried on concrete by replacing 20%-30% cement in equal mass. HBC and AF win remarkable economic performance.Expanding agent WUT with multi-expensive source and long terms expanding, made from HF, steel slag and fluorin gypsum, is developed. Zero shrinkage keeping time of concrete delays to 90d from 28d keepped for by expanding agent UEA and CAS,...
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