Pretreatment of Straw Pulp and Papermaking Middle Stage Wastewater by Iron-Carbon Microelectrolysis

Iron-carbon microelectrolysis was used to pre-treat straw pulp and papermaking middle stage wastewater. Effect of iron dosage, iron/carbon ratio, initial pH, aeration and aeration pattern on the pollutant removal efficiency was investigated and the biodegradability of wastewater before and after treatment were compared. The results showed that the iron dosage affected pollutant removal slightly in the experimental condition. When iron/water ratio was 0.15:1, COD removal rate was the highest. The pollutant removal efficiency was influenced by iron/carbon ratio and initial pH. The optimal iron/carbon and pH was 1:1 and 3, respectively. Aeration was helpful to the pollutant removal by iron/carbon microelectrolysis. Aeration pattern could affect microelectrolysis process, sufficient aeration could increase COD removal rate by 15.6%. After treated by microelectrolysis, BOD5/COD ratio could increase from 0.26 to 0.42.