| As the main solid waste of coal-fired power plant, the annual emission of coal fly ash is up to 30 million tons, and the annual ash reservoir area increased is up to 82.37 thousand acres. So much coal fly ash needs a large of cropland to deposit and cause many environment problems in atmosphere, water and soil environment. Only a little of these fly ash is used as building materials products, building engineering, transportation and soil improvement etc. The recycling technique of the fly ash seems to is more rough, and the industry chain is so short. And the researches which apply coal fly ash into the usage of wastewater treatment have not achieved some important results and the research depth is inadequate. These researches didn't develop new paths in comprehensive utilization of the valuable resource to the greatest extent, and most of studies are still at the stage of laboratory research. Apply modified fly ash to the treatment of industrial wastewater, such as papermaking wastewater and acid mining wastewater, which have a large quantity of volume, contain complex pollutants and possess a larger potential re-usage. Use this process as the pretreatment of the wastewater. After several processing means, transact the sludge of wastewater treatment to produce environmental-friendly cement, realizing the recovery resource and comprehensive utilization, and these works can obtain good environment efficiency, economic efficiency and social efficiency.There are very good effects on papermaking wastewater and acid mining wastewater treatment used modified fly ash. The burden of follow-up processing facilities will be lightened. The sludge of wastewater treatment could be used as cement admixture material after anhydration and drying treatment, to produce fly ash eco-cement. And every technological index accords with national standards GB175-2007, Common portland cement, strength grade is up to 52.5 R.
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