Preparation Of Palygorskite-based Porous Ceramic/Palygorskite-based Wood Porous Ceramic And Their Applications In Wastewater Treatment

In the biological aerated filter operation and design, selection of suitable packing biological aerated filter is significant for widely application of biological aerated filter technology. To overcome the general ceramic filler surface glaze,low open porosity and increase the aggregate load and biomass, a novel biological ceramsite:palygorskite-based porous ceramic/carbon was prepared.A study was conducted on the mass ratio of reaction materials and clacination technique to investigate the properties of ceramsite which have been prepared by calcination with palygorskite, sawdust and sodium silicate. Furthermore, in various tests for the ceramsite, strength was the principal factor to determine the mechanical properties of ceramsite. To choose the most suitable product, porosity, calcination temperature and time were introduced as factors in orthogonal experiment design to determine the preparation of palygorskite-based porous ceramsite (PC). The results showed a promising combination of palygorskite clay, sawdust, and sodium silicate (the mass ratio is10:2:1) would ensure PC conforming to the state industrial standards (CJ/T299-2008) of water treatment. SEM results also proved the uniform and interconnected pores in PC were suitable for microbial growth.The results showed that:in the air atmosphere, preparation of ceramic particles with best quality ratio of attapulgite clay/sawdust/water glass=10:2:1; the optimal calcination conditions (700℃, calcined for3h) in a nitrogen atmosphere, preparation of ceramic best quality ratio of attapulgite clay, sawdust water glass,68:20:12, the optimal calcination conditions (700℃), in two different atmosphere and different ratio of raw materials, can be prepared to meet the national standard of water treatment using ceramic; by electron microscopy revealed the prepared two kinds of ceramic exist within large distribution,3D interlated pores, suitable for the microbial attachment. In comparation experiments between BAF-PC and BAF-WPC, COD and ammonia nitrogen removal rates were both more than80%. For the hydraulic loading of2m/h,1KgCOD/m3·d of organic loading, the optimal air-water ratio should be3:1. BAF-PC and BAF-WPC simultaneous nitrification denitrification process has strong shock resistance ability. In simultaneous nitrification and denitrification technology, COD and NH3-N removal rate increases with increasing filler height.