| Suspended porous carriers is the developing direction of carrier of moving bed biofilm reactor with the advantages of high microorganism loading, high treatment efficiency and low energy consume. In this paper, a novel porous carrier making use of cellulose was developed. This carrier has high porosity and specific surface area, and it is low cost and biodegradable. Cellulose viscose was firstly prepared by alkalifying and esterifying cellulose, then the carrier was obtained after being foamed and regenerated. The optimum prepare condition of viscose is: NaOH concentration 20%, basification temperature 20, NaOH dosage 50ml/10g(cellulose), esterification temperature 30℃, CS2 5g/10g(cellulose), and esterification time 90min. Using azodiformamide as foaming agent, the foaming temperature ranged from 100℃ to 160℃, and some cotton fiber was added to improve the strength of carrier. The porosity and the specific surface area of the carrier can reach to 80% and 10m2/g respectively, and the carrier aperture ranged from 100μm from 700μm. The effects of foaming agent dosage, foaming temperature, cotton content and viscose concentration on 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, with the decompose time of crosslinked carrier ranging from several days to several months.
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