Garlic Wastewater Pretreatment Approach Study

With the further deepening of China opening to the outside world, and accelerating of the pace connected to the world, the demand in the import and export of agricultural products substantial increase. Therefore, processing enterprises of agricultural and sideline products also increased year by year. In recent years, during the process of produced some of the garlic in vegetable fabrication plant, the amount of wastewater has increased year by year, producing by selecting, cleaning up, slicing, rinsing, dehydrating, separating, packaging. The wastewater contains a lot of organic pollutants and suspended solids. At the same time there is smelly sour, in which most of the content is allicin. It is a kind of organic matter which has the antibacterial and bactericidal effect, and has a very powerful lethal to bacteria, leading to bad biodegradability, so the treatment effect of using conventional biochemical methods is not available.Meanwhile, China’s technology of dealing with the wastewater is still in the early research stage. Therefore, it is extremely urgent to speed up the research of the garlic wastewater. The research can not only reduce water pollution, but also protect the environment, reduce the waste of water resources, thereby it could create a higher economic benefits and significant social value.It could use Plus acid plus alkali treatment, the Fenton reagent handling and microelectrolysis-Fenton joint process to treat high concentrations of organic matter content in the pre-treatment trials. Possibility of influencing factors impact testing to determine the parameters of the acid-base processing by a single factor, use the same single factors optimal reaction conditions of the test to determine Fenton reagent handling, processing test demonstrated iron-carbon micro-electrolysis-Fenton joint experimental values.The results of adding acid plus alkali test show that this way, treating cod content of garlic wastewater, would work. And adding acid removal rate is relatively high, but the effect is not obvious, the removal rate of less than25%of the highest. Fenton’s reagent as a pretreatment garlic wastewater experimental results show that the Fenton reagent oxidation pretreatment the garlic wastewater is feasible, its optimal operating conditions:of H2O2dosage of20ml/1H2O2and Fe2+optimum molar ratio of1:1, the best reaction PH=3, reaction time of30min62.5%, the average cod removal rate under this condition. Micro-electrolysis-Fenton joint processing test results show that, pH value of the iron-carbon micro electrolysis of water pH=4, the reaction time of30min, H2O2dosage of20ml/1, and cod removal rate can reach more than70%under the optimum conditions.The using of acid pretreatment processing alkali aeration and temperature process organic sulfides in garlic wastewater, by testing to research and explored.Experimental data show that in the acid-base pretreatment study, after being acid-base regulated, garlic wastewater under strongly acidic conditions turn from light yellow to become white, and produce a large number of white flocculent precipitate. Under the condition of pH=2～4, organic sulfide removal efficiency in garlic wastewater can be achieved more than80%to90%, the optimal conditions for removal of organic sulfides in the garlic wastewater is strongly acidic environment.The results of adding alkali aeration experimental show that, under alkaline conditions, aeration accelerate the volatilization of the organic sulfides in the garlic wastewater, but garlic wastewater SO42-removal efficiency and the COD removal efficiency is not high.Higher temperature and heating will increase the speed of volatility and degradation of organic sulfides in garlic wastewater, which have a role in the removal of organic sulfides, but the effect is not obvious.