Experimental Research On Advanced Treatment Of Pulping And Papermaking Wastewater And Its Engineering Application

The paper industry is the key control industry in China,and the wastewater discharged from the industry is the key object of environmental monitoring.Based on the background of three large pulping and papermaking enterprises in Henan Province,the best operating conditions for advanced treatment of three pulping and papermaking enterprises were determined by coagulation precipitation or coagulation Fenton oxidation test.The effect of tailwater purification of three types of pulping and papermaking wastewater under different operating parameters was studied,and the mechanism of coagulation precipitation and Fenton oxidation on three types of wastewater was discussed.And satisfy this permitted emission standards of three enterprises,and implement engineering applications.It can provide reference for the design,construction and commissioning of similar wastewater advanced treatment projects.The study found that:?1?The removal rate of biochemical wastewater COD in a special pulp and paper enterprise in Henan reached the best when the amount of polyferric sulfate was2.8 m L/L,the removal rate of COD reached 83.13%,the effluent COD decreased from the original 150?160 mg/L to less than 30 mg/L,and the chroma decreased from64 times to 4 times.?2?The removal rate of biochemical wastewater COD of a pulping and papermaking joint enterprise in Henan reached the best at 2.4 m L/L,the removal rate of COD reached 72.11%,and the COD of effluent decreased from 150?300 mg/L to69.The optimum operating conditions were as follows:adjusting initial pH around3.5,30%H₂O₂dosage 0.5 m L/L,[H₂O₂]/[Fe²⁺]molar ratio 4?1,reaction time 60 min.COD removal effect to the best.?3?The removal rate of biochemical effluent COD in a APMP pulping enterprise in henan reached 87.38%when the amount of polymeric bauxite was 10m L/L,and the COD of effluent decreased from 700?1000 to 101 mg/L,and the chroma decreased from 128 to 16 times.The optimum operating conditions for Fenton oxidation test of coagulant effluent were as follows:the pH value of coagulant effluent was not adjusted,30%H₂O₂dosage was 0.5 m L/L,[H₂O₂]/[Fe²⁺]molar ratio was 4?1,and the COD removal effect was achieved at 90 min reaction time best.?4?The effect of Fenton reaction reagent is better than that of one-time dosage,COD the removal rate is increased by about 5 percentage points.?5?Cl^-concentration in wastewater will affect the treatment effect of iron coagulant,and high Cl^-concentration will lead to poor coagulation effect.Cl^-high content of wastewater in Fenton oxidation,will affect the Fenton oxidation,affecting the quality of effluent.?6?According to the data of the small scale test,the construction and debugging of the field project are carried out,and it is found that the actual operation effect is better than that of the small scale test,and the operation effect is stable.The effluent COD of a special pulp and paper enterprise is basically between 20 mg/L?40 mg/L after coagulation and sedimentation.The actual running effluent COD meet the permitted discharge standard of the pulping and papermaking industry water pollutant discharge standard?GB3544-2008?The discharge standard"discharge standard of water pollutants in honghe river basin"?DB41/1257-2016?is sufficient for the enterprise;the effluent COD of biochemical effluent from a APMP pulping enterprise after coagulation Fenton oxidation is basically within the range of 20 and 30 mg/L,and the actual running effluent meets the allowable discharge standard of the enterprise"discharge standard of water pollutants in river basins under provincial jurisdiction"?DB41/777-2013?.?7?The advanced treatment medicament cost C enterprise>B enterprise>A enterprise,unit COD medicament operation cost B enterprise>A enterprise>C enterprise.