| Suspended porous carrier, with advantages of high microorganism loading, high treatment efficiency and low energy consuming, is one of the directions of carrier for fluid bed biofilm reactor. In this paper, a novel porous carrier made from wheat straw was developed and researched, and the optimum preparing condition was concluded. Firstly, cellulose viscose was prepared by alkalifying and esterifying wheat pulp, then the carrier was obtained after being foamed and regenerated. The optimum condition of preparing viscose is: NaOH concentration 20%, basification temperature 20℃, NaOH dosage 50ml per 10g wheat pulp, esterification temperature 30℃, CS2 dosage 4.4g per 10gα-cellulose, and esterification time 90min. Using NaHCO3 as foaming agent, the foaming and regeneration process were carried out in hydrochloric acid or sulfate solution at the meantime. The porosity and the specific surface area of the ca- -rrier can reach 86.98% and 11.59m2/g respectively, and the carrier aperture ranges from 100μm to 800μm. The effects of foaming agent dosage, regeneration bath va- -riety and viscose characteristic on shape, porosity, specific surface area, aperture and carrier strength were discussed, and the optimum process condition was concluded. The carrier's degradation speed was controlled by crosslinking cellulose with epoxy compound, and the carrier's biophile character was increased by reaction with catio- -nic compound. This low-cost porous carrier, with high specific surface area, appro- -priate aperture, controllable biodegradation speed and good biophile character, is a high efficient, environmental protection product for wastewater treatment.
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