Cement hydration utilization

Many inorganic and organic salts have been examined for their action on the hydration of cement and cement compounds utilizing thermal techniques. They include sodium and calcium salts of chloride, bromide, nitrite, thiosulfate, thiocyanate, iodide, nitrate, hydroxide, carbonate, hydroxide, etc. A few typical examples are given illustrating the application of thermal techniques in the investigation of these compounds on cements and cement components. 

The inherent instability of sulfur-infiltrated concrete in aqueous media illustrated in this study may be the most important factor in utilization, because it will affect long-term durability of the concrete in many natural settings. The Ca(OH)2 produced by the hydration of portland cement is a principal reactant in the leaching process, and while it remains sulfur could be extracted, leaving the matrix vulnerable to other destructive processes. The removal rate of sulfur will vary greatly, depending mostly upon the pH of the immersion medium thus, the concrete deteriorates in alkaline sulfatic soils but is relatively stable in the corrosive neutral sulfatic solutions from the sodium sulfate plant. 

The aim of the work is to develop new cement admixtures by using bentonite clay, PVA and their mixture. The study of the effect of PVA and clay on the hydration rate of cement paste will be done, as well as, characterization of the final modified cement by means of FTIR, TGA and SEM. From our knowledge, there is not previous publication utilizing these admixture combinations in cement. 

Waste mud has a high water content and is muddy. If the water contained is reacted with a hardener such as cement and a hydrated mineral is formed, the mud plasticizes or hardens. If cement is added to waste mud and cured, the strength created will depend on the amount of cement as shown in Fig. 6. Thus a hardening treatment utilizing cement to treat waste mud as well as sludge has been done for many years. However, in order... 

Pressurized fluidized bed combustion (in a coal-fired thermal plant) offers efficiency and reduction in environmental loads. The coal ash produced in this process is a consequence of firing a mixture of pulverized limestone and coal. In this process, the mixes are burned at a lower temperature than that carried out in the conventional power plant which produces fly ash. There is a possibility of utilizing coal ash as an admixture in concrete. Thermal analysis of the hydration products obtained at different w/s ratios fi om coal ash-cement pastes indicated substantially lower amounts of lime than that estimated in pure cement pastes, This indicates... 

CSH, tobermorite, xonotlite and related materials are being widely utilized in recent years. It is produced on autoclaved lightweight concrete, autoclaved concrete, sand-lime blocks, hydrous calcium silicate he at-insu1 ation materials, hydration products of cement and other building or construction materials. 

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