Preparation And Properties’ Study Of Geopolymer Composited By Heat Activated Sludge And The Solid Waste Of Coal

The geopolymer is a new kind of cementitious material, whose preparation process consumes less energy and resources. It owns many excellent properties, such as high strength, high toughness, corrosive acid and alkali, solid seal toxic substances, better performance of flooding and so on. So many workers in related fields started to pay attention to the research to the preparation and properties of geopolymer.Firstly, through the XRD,TG-DTA analysised of heat activated sludge, we determined the optimum heat activated temperature of sludge is900℃. Next, we used the heat activated sludge and coal solid waste(Including gangue and fly ash) to prepare geopolymer under alkaline excitation conditions. Through the macroscopic and microscopic properties testing of the prepared geopolymer, exploring the feasibility of using the heat activated sludge and coal solid waste to make the geopolymer. Research of this paper comes to the following conclusions:1. The geopolymer prepared with heat activated sludge and gangue after being conserved3d and28d respectively, by compressive strength test, we can know that the best ratio of heat activated sludge(under80mesh) and gangue(under60mesh) is40%:60%, at that time we can get the geopolymer, whose compressive strength could get up to39.8MPa. Through XRD, SEM and FT-IR testing, we did the phase analysis, observed the appearance and confirmed the position of bonds (Al-O, Si-O, Si-O-Si, Si-O-Al) and bound water, verified the feasibility of the preparation of geopolymer using thermally activated sludge and gangue.2. The geopolymer prepared with heat activated sludge and fly ash after being conserved3d and28d respectively, by compressive strength test, we can know that the best ratio of heat activated sludge(under80mesh) and gangue(under60mesh) is40%:60%, at the same time we can get the geopolymer, whose compressive strength could get up to21.5MPa. Through XRD, SEM and FT-IR testing, we did the phase analysis, observed the appearance and confirmed the position of bonds (Al-O, Si-O, Si-O-Si, Si-O-Al) and bound water, verified the feasibility of the preparation of geopolymer using thermally activated sludge and fly ash.3. Heat activated sludge, gangue, fly ash according to a certain proportion are used to make the geopolymer, after being conserved3d and28d respectively, by compressive strength test, the conclusion is while using no heat activated sludge and the ratio of gangue and fly ash mixed with one to one, the compressive strength of geopolymer could high to52MPa.4. Drawning the above conclusions, The best ratio of gangue and fly ash used to prepare geopolymer becoming our further study direction in this paper. Using the same methodology, we got those following conclusions:using40%amount of fly ash incorporated into the gangue and under the alkaline condition, we get the geopolymer whose compressive strength could high to55.4MPa.5. Testing macroscopic and microscopic properties of the higher compressive strength test block prepared with gangue and fly ash, the conclusion is that after the weathering test, high temperature test, and flooding test, although there was a little of degree exist loss of compressive strength of the better geopolymer block, the compressive strength of the whole is greater than15Mpa. These show that the geopolymer prepared with gangue and fly ash owns better weathering, high temperature, flooding performance. After the acid corrosion testing, the mass loss of the test block does not exceed1.2%, to compressive strength, although the change rate is much bigger(more than15%), the whole shows a growing trend, Which means that the geopolymer test block owns much better acid corrosion performance.