| Coal fly ash is a kind of waste outcome from coal fired power stations and the total production is increasing with the development of economy. Currently, the total amount of discharge for coal fly ash is up to two hundreds million tons per year but less than 50% of coal fly ash is utilized in China. This represents a huge negative environmental impact mainly including the pollution of soils and groundwater. In this thesis, light-weight foam materials were prepared by pore-foaming agent method and slurry foaming method. The effects of various kinds of process conditions on performances of sample were investigated and high-quality foam agent was obtained by orthogonal test. In summary, this thesis is composed of three parts as follows:(1) Light-weight material was prepared by pore-foaming method. The effects of agents on sample performance were studied. The results show that:when the dosage of the agents was between 5 wt.% and 10 wt.% and the sintered temperature is 1050℃, the samples prepared under the conditions above mentioned come up to the standard GB 5101-2003 MU10.0.(2) The preparation of foam agent is the key step of the slurry foaming method. The results show that:the weight ratio of foam stabilizer, frothing agent were 8:2.5, respectively; the weight ratio of frothing agent, foaming agent were 10:1, respectively.(3) The activation was studied. In this thesis, alkali was used to activate coal fly ash and the process was studied, too. The optimal dosage of alkali is 3 wt.%.(4) The sample with homogenous microstructures of pores was prepared by slurry foaming method after alkali-activation. The related factors were optimized:the weight ratio of coal fly ash, sodium hydroxide were 97:3, respectively; water cement ratio was 0.40; the amount of foam was 13 wt.%; sintering temperature was 1050℃. The samples come up to the standard GB 13545-2003 MU5.0.
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