| Sludge Removal Liquid is a kind of high concentration refractory organic wastewater generated from the sludge Steam Pyrolysis Technology, and its properties are similar to industrial wastewater such as coke wastewater, dyeing wastewater, pulp and paper wastewater, landfill leachate et al., which have features with high concentrations, large color, thick odor, complex components, contains a large number of refractory materials and so on.If it is direct discharged into waterbody will cause great harm to the environment and the human body, and will have a great impact on treatment facilities load, affect the subsequent biological treatment process if it is discharged into the municipal sewage treatment plant. This thesis uses Sludge Removal Liquid as research object, proposed the Micro-electrolysis united Electro-Fenton pretreatment process to explore the effects of the treatment process and the influence factors, and determine the optimum process conditions.Under the premise of demonstrating the properties of the Sludge Removal Liquid, the common treatment methods to high concentration refractory organic industrial wastewater such as coagulation, electrocoagulation, micro-electrolysis and other processes were compared and analysed, it is found that micro-electrolysis process not only has good treatment effects, also has low cost advantage; through orthogonal and strengthening experiments, we draw the best aspects of micro-electrolysis process conditions, they are inlet pH 3, the volume ratio of iron to carbon is 1:2, the volume ratio of iron to wastewater is 1:2, while the iron-carbon bed is ultrasonic aggrandized, and for a two stages treatment of total 30min.We can get the influent sequence of the factors from orthogonal experiment,that is the volume ratio of iron to carbon> pH value> the volume ratio of iron to wastewater> reaction time; the Electo-Fenton feasibility study and single factor experiments showed that the treatment of the micro-electrolysis effluent with very good results, the optimum conditions for the link are current density is 30mA/cm2, pH is 3, electrode distance is 2cm, H2O2 dosage is 5.0% , reaction time is 90min, and through compared with the UV-Fenton, we found that the Electro-Fenton has some advantages in conditions controlling, cost saving and so on.Experiment show that, before the micro-electrolysis treatment of Sludge Removal Liquid, adjusting the raw water pH to 3 can removal of 17.3% CODCr by acidification; micro-electrolysis link removal rate of CODCr reache 50%, while the total CODCr removal rate is close to 60%;Electro-Fenton treatments the returning diluted micro-electrolysis effluent, the CODCr removal rate is above 90%. After the entire treatment process, the CODCr removal rate of Sludge Removal Liquid is reached to 98.3%, the BOD5 removal rate is achieved to 96.4%, the color removal rate is acquired to 99.6%, BOD5/CODCr value is increased to 0.56, biodegradability is heightened, the effluent qualities reach the three-level emission standards of the Guangdong Province "Discharge limits of water pollutants"(DB44/26-2001), the effluent can be let to the local municipal wastewater treatment plant for further advanced treatment.The process is easy operation, high efficiency, little secondary pollution, cost-effective, and has the feature of "controlling waste by waste". After a preliminary calculation we know that, the cost of the process is less than 90 yuan/ton. So, using the process to pretreat the Sludge Removal Liquid is possible.
|
PDF Full Text Request