Experimental Study on the Start-Up Stage of Wheat Straw Pulp and Paper Wastewater Treatment in Immobilized and Suspended Biomass Combination Processing

The study on the start-up of the pilot-scale immobilized and suspended biomass combination processing to treat the comprehensive effluent from a wheat straw pulp and paper plant was performed. The carrier packing selected in this experiment is a new type of microbial carrier (modified polyurethane foam plastic packing) which dosing rate was 20% of the reactor volume. The low quantity of inoculation sludge way is used to start the system. The test results show that the removal efficiency of COD and SS by the immobilized and suspended biomass combination technology system after a weak or so can be stable, as the effluent SS was below 50mg/L, the removal rate of 95% or more and the effluent COD was below 260mg/L, the removal rate of 85% or more. From start to 10th day, the attached sludge concentration on biomass conversion was more than 20g/L, while the microscope observation to biological adherent microbes suspended sludge and carrier phase indicated abundant microbial species. The fact indicates that the start-up can be finished in 10 days.