| The total water resources in China ranks 6th in the world, per capita amount of water in the world 84, water resources is scarce. Xinjiang is a typical area of arid-semiarid, lacking in water which is restricting the development of economy and society. Oil is the most preponderant industry in Xinjiang. The oily sewage is increasing accordingly with augmentation of oil's exploitation and use, which is harmful to the environment and makes water going short. The oily sewage can be used repetitively and decrease the pollution after appropriate disposal. Recycling of oily sewage is the most effective method to solve the problem of water lacking and improve the use of wastewater, which is significant to the economy and society of Xinjiang.The main component of bentonite, fly ash, sepiolite and diatomite is silica, which is hydrophilic. Generally they are modified in order to further improve its adsorption power in practice. There are lots of methods on wastewater treatment, each of them has its own disadvantage. Adsorption is one of the general methods, which is easy to operate and has an obvious effect. But the majority sorbent is active carbon, which is expensive and hard to be used repetitively. New sorbents are searched to replace active carbon. There is a great reserves of bentonite,sepiolite and diatomite, which is cheap and have fine adsorptive ability. Fly ash is castoff of power house, low use ratio and bad to environment. The use of fly ash on wastewater treatment can decrease the pollution and benefits on the economy and society.Four kinds of sorbents were used on oil sewage treatment,modified by DATB, based on the orthogonal test which was developed by the factors such as amounts of DATB,modified time,temperature and mixing time. The effects of the factors on wastewater treatment and the removal of COD, oil, ammonia nitrogen and volatile phenol was studied to get the better modified conditions. The results showed that: the optimum conditions for modified bentonite was DATB 2g, reaction time 9h, the reaction temperature 60℃, mixing time 30min; the optimum conditions for sepiolite modified was 5g, 3h, 60℃, 90min; the optimum conditions for fly ash modified was 2g, 6h, 60℃, 180min; the optimum conditions for diatomite modified was 5g, 9h, 80℃, 30min.The characteristics and structure about the sorbents and modified ones were investigated by IR,TG and XRD, and the change and the influence on wastewater treatment was studied. The results showed that: the organic cation of DATB was inserted to the structureof absorbent which makes the layer spacing increase and improve the capacity to organic pollutants.The influence of adsorption time,pH,amounts of sorbet and temperature were discussed to get the better experiment conditions, base on the removal of COD, oil, ammonia nitrogen and volatile phenol. The results showed that: time 90min, pH 7.0, adsorbent dosage 1g/100ml, temperature 25℃was the optimum conditions for wastewater treatment, the removal under this condition was increased by about 30% than the former ones.The adsorption isotherms were discussed based on different adsorption equation and the parameters.The results showed that: adsorption to COD,oils complied with the Freundlich adsorption isotherm; adsorption to phenol complied with Langmuir adsorption isotherm; adsorption to ammonia both complied with Freundlich isotherm and Langmuir isotherm.
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