Research On High Concentration Debiodegradible Organic Wastewater Treatment Technology And Process

The characters of industry wastewater were summarized in the paper,such as large flow quantity, high concentration organic, color, toxic,debiodegradation, and so on. Discharged straightly without being treated,these wastewaters would pollute environment. The treated wastewater met therequirements of the discharge standard by the usual present treatment process,but many entrepreneurs can't afford the high investment and running cost.Then, these entrepreneurs often discharge wastewater blinkingly, and it willgive rise to pollute environment seriously, and harm people's health finally.The experimental research of industry wastewater was from pretreatmentand catalytic oxidation technology method for high concentration organic anddebiodegradation industry wastewater, and the treatment process of dyewastewater was given. The research content was included:1 The research of industry wastewater of pretreatment technologyby micro-electrolysis methodThe pretreatment process of micro-electrolysis and Fenton had manyadvantages,such as less investment , low running cost , simple processoperation, and high efficiency etc. it can especially be applied to preterit thedebiodegradation,high concentration organic industry wastewater.The pretreatment process of micro-electrolysis based on forming lots ofmicro-batteries in acidity by the mixture of the granular scarp iron and activecarbon. In this process, it could produce ·OH, which was high oxidation andcould break some constuction into lots of simple organics and some ultimatedegradation. For example, ·OH could break –C=C–, –N=N–, –N=O, biphenyl,and so on. What's more, in the process of micro-electrolysis, Fe was import,too. It could deoxidize organization and some heavy metals (Cr6+, Cu2+,Ni²⁺ect.) .At the same time, this reaction produced lots of Fe2+ and Fe3+. In thesuitable pH, they and heavy metal ions could sedimentation in the form ofalkali. Various inorganic and organic colloidal particles were adhesived andsettled out in a reasonable time. All of them could degrade the situation ofalkali of pollution. However, the sludge should be treated through incinerationand ion exchanging, avoid the second population.Because the water through the actor of micro-electrolysis contain lots ofFe2+ and Fe3+,and Fe2+ was necessary in the Fenton process, if added H2O2to it, the organic concentration could be degraded because of oxidation. Sothe effect of micro-electrolysis was enhanced. Through the pretreatment ofmicro-electrolysis, not only degraded the contention of CODcr, but alsoraised the biodegradation, which was good at the following biodegradationprocess.The usual material of cathode in micro-electrolysis was active carbon,but some materials, coking ashes for example, which contained carbon,could take the place of active carbon. In this way, the effect was the same,but the investment was low, and this process had the advantage of using thewaste circularly. However, coking ashes had some shortcoming, for example,wastage and blocking. The θ padding, a new structure of padding, had largesurface area and void, and padding can be fluidized by water flow, so itstrengthened mass transfer and solved the problem of scrap iron hardpan.2 The research of pretreatment industry wastewater by catalyticoxidation technologyThe advanced oxidation processes (AOPs) based on producing theradical utilize the radical to attack the giant molecule of hard degradedorganic and remove the contaminant and treating high concentrations of harddegraded organic waste water. But AOPs often have difficulty to popularizeand application in practice, due to the cost very expensive. Because someoxidant have more strong selectivity, then more and more oxidant have beenneeded for get some better oxidation effects.Catalytic oxidation technology is the advanced and enforced technologyof AOPs. The catalysis of the catalyst can lower the temperature and pressureof reaction, shorten the time of reaction and prevent the erosion on equipment,so the rate of oxidation reaction have increased and the cost have reduced.Especially the heterogeneous catalytic appear these advantages. Because theheterogeneous catalytic in the face of solid, the effect is better, and theseparation of catalyst and wastewater is simpler, so the operation is simplerand it could availed these problems such as the catalyst is dissoluble to thewater, it can not be reused;the cost of the reagent is higher, etc. However, theheterogeneous catalytic oxidation technology still has some problems, forexample the high reaction temperature and pressure, the hardness of treatingthe large flux wastewater and expensive reagent etc.The catalytic oxidation technology in low temperature was utilizedcatlytic function in active component of catalysts, by the use of ·OH whichwas produced through oxidant divided take palce linked-reaction, ont only didthey degraded reaction temperature and pressure and shorten reaction timeand increased reaction velocity, but also decreased digestion of enegy andtreated cost.3 The reseach content and results of kinds of pretreatmenttechnologyThe purpose of research: study the mechanism, pretreatment effect andthe influencing factors of the microelectrolysis-Fenton process and the lowtemperature catalytic oxidation technology for the dyes wastewater treatment.The result of experiments showed the optimal parameter that would beprovided to the engineer the design and running operation.The conclusions of research:(1) The micro-electrolysis bed of consisits of the granular scarp iron andactive carbon, when wastewater pass through it, it will be take palce a seriesreaction of electro-chemical and physical-chmistry. It contains lots of Fe2+ intreated water, and it will be formed Fenton reaction with added H2O2, that isstrenghted micro-electrolysis method. The results of synthetic analysisshowed that there were almost aromatic compounds, less organic compoundsof straight chain in the raw chemical synthetic dyes wastewater. There wereopposite organic components after pretreatment, the aromatic compoundswere disassembled into organic compounds of long straight chain, H2O andCO2 in the pretreatment process. The biodegradation of wastewater wasimproved.(2)Through pH adjusted, metal iron was sedimentation in the form ofalkali. Various inorganic and organic colloidal particles were adhesived andsettled out with some organic. Then the wastewater was purified more.(3)It was practicable to preterit printing-dye wastewater, chemicalsynthetic dyes wastewater by the micro-electrolysis and Fenton process. Thegood effect was tested, the removal rate of COD is above 50%, and thebiodegradation was rising from 0.04 to 0.3 above, so that the effluent can betreated by microbiological wastewater treatment process.(4)The results of experiments showed that influent wastewater pH, ratioof scrap iron to carbon , padding granularity, the reaction time ofmicro-electrolysis , the sedimentation pH, the quantity of PAM ,the reactiontime of Fenton, the quantity of H2O2 were the mainly influencing factors ofthe pretreatment process. The best condition is: Fe/C is 1.0-1.5;reaction timeis 1-2 hour;the granular scarp iron particle is 24-32;pH value ofsedimentation is 8.0-9.0;PAM is 3ml/L;H2O2 is 3ml/L;Fenton's reactiontime is 1-2hour.(5) The new structure of θ padding has larger specific suface area andvoid, padding can be fludized by water, so it will be strengthed mass transferand efficiency of the micro-electrolysis be prompted. At the same time, theproblem of scrap iron hardpan was solved, so new padding is very sutaible forthe process of the micro-electrolysis.(6) The adsorption performance of catalyst has been studied for treatinghigh concentration and debiodegradation industry wastewater. The studiedfound the factors at low temperature and atmospheric pressure. Whentemperature is 40℃;the pH value is 3;the dosage of catalyst is 100g/L;thedosage of oxidant is 120ml/L and the reaction time is 1 hour, the removal ofcatalytic oxidation is optimum. The remove ratio of CODcr is 63%.(7) XRD figure show that some character peaks had disappeared becauseof the fuse of Cu. Cu2O and CuO are main form of Cu in catalyst and loadedfirmly. Compare the XRD of pure γ-Al2O3, fresh catalytic oxidation withcatalytic oxidation which is used, could found the copper exist in the form ofCu2O and CuO, in catalyst and firmly.4 The project of process conbined treatmentCompare strengthen micro-electrolysis technology with catalyticoxidation technology, given the project of process combined treatment forsynthetic dye wastewater, which was strengthen micro-electrolysistechnology-anoxic biodegradation treatment-aerobic biodegradationtreatment method, the concentration of COD in the discharge water was under95mg/L and met the discharge standard.