| At present, the rate of CO2 emission quantity by the whole world cement industry production to CO2 absorption quantity by building concretes in 70 years is about 9.43, so the cement industry system's carbon equivalent transmission chain has already been completely unbalanced. And industry solid rejectamenta synthesis using rate in our country is less than 40%, has accumulated to 7,000 million ton and occupied a land area for approximately 70,000 square kilometers. The construction of a resource-economical and environment-friendly society need to make it to become the control characteristic cement material and reduce the resources consumption and the pollution emissions in the cement industry production process.This research work originates in (973 Program. Project 2009CB623201) and (National Key Technology R&D Program. Project 2006BAF02A24). Us the most widespread fly ash and slag by at present as the representative inorganic silicon-aluminum character material, verify its chemical activity characteristic and the hydration mechanism under the multi-factor environment, carry on the surface texture depolymerization through the physical chemistry method to strengthen its chemical activity, study the cooperative effect match relations among inorganic silicon-aluminum character materials, then carry on the preparation key technologies satisfying the industry near zero emissions principle design by cooperative effect, active stimulation technology, special component optimization and so on.1. The synthesis chemical activity appraisal system is established for the first time, through the strength performance, the non-evaporation water quantity, the reaction degree and the K(?)-ICP performance of fly ash, slag in hydrothermal and alkaline environment.(1) Fly ash granule react with Ca(OH)2 and generate CSH monolayer film or CSH double deck film at initial stage which adhere to the granule surface. The formation of reactant reduces the increase speed of Ka value at initial stage. The area where is easy to react forms activation point to promote reaction medium to react continually. activation point enlarges more at later period, and most active SiO2,Al2O3 in fly ash will react completely, and the inert mullite and newborn mineral-zeolite which doesn't react in this process will form joining structure with hollow shape.(2) In the fly ash and cement binary system, there is one kind of balanced relations between production quantity of cement hydration Ca(OH)2 and consumption quantity of fly ash chemical reaction Ca(OH)2. And the difference of Ca(OH)2 density used in fly ash chemical reaction is along with its wraps film thickness in each reaction stage's surface texture and activity, basically presents the increasing tendency with its film thickness.2. Has developed research on the superficial depolymerization and the chemical activity stimulation effect of inorganic silicon-aluminum character material stimulation system under the different hot historical.(1) Propose the optimized way in high temperature increasing the calcium environment:Firstly, use the CaO-SiO2-Al2O3 three phase diagram analyses and the free calcium oxide test to determine probably the calcium mixed quantity and temperature sector, then make sure optimize allocated proportion of calcareous (CaO) using the high temperature microscope.And through 29Si/27Al NMR, FTIR and so on to carry on the analysis the modified fly ash silicon-aluminum network structure, and use the chemical activity appraisal system to conduct the active characteristic analytical study. And the optimal allocated proportion is CFA-4-1200℃, namely 81.0%LCFA1+15.0%CaO+3.0% gypsum+1.0% fluorite, temperature system is under 1200℃for 0.5h.(2) By 29Si NMR result analysis, comparing to original condition FA, the strong crest lines of modified fly ash by high temperature displacement toward plus direction, present the tendency of the high field centralism to the low field scattered, indicates that its network architecture polymerization degree has reduced. Unify 27Al NMR to carry on the mechanism analysis, in the high temperature increasing calcium environment, calcareous is extremely easy to invade in the middle of the silica polymerization structure and makes the network architecture be not steady, and the Si-O key's break will make the high coordinate network intermediate Al and some Ca permeate, thus cause the strong peak chemical in the network architecture shift to the low field, and the chemical activity of modified fly ash could be enhanced inevitably.3. Introduce into the concept about chemical activity response time-limited contribution rate for the first time, and there are mainly two understanding points to the grading hydration theory:Firstly, this theory mainly aims at the chemical activity to respond of compound system various components without considering other effects, such as micro aggregate effect, shape effect and so on; Secondly, reasonable understanding about the grading should be its time-limited contribution rate in certain order, namely various components hydration response has been existing, but there is certain order or overlapping superposition on response efficiency in various time section.4. Through the hydration heat, the volumetric deformation, the dehiscence sensitivity and the anti-sulfate corrosion test, carry on the multi-dimensional system high performance compound cementious material design and the performance study.Unify the multi-dimensional system cooperative effect the research preparation high performance compound cementious material to set 45% mixture rate of solid rejectamenta. its 1d hydration heat drops above 30%, the dehiscence sensitive aspect's initial dehiscence time lengthens above 175% to datum type, the 28d linear shrinkage reduces above 25% to datum type, the anti-sulfate corrosion performance enhances above 45% to the datum type (according to ASTM the C1012-95A standard).
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