Experimental Study On The Treatment Of Food Waste In Upflow Anaerobic Sludge Blanket Reactors At Normal Temperature

With the improvement of the level of living in our country and the continuous development of catering industry, the production of food waste fiercely increased. Food waste is rich in organic matter and nutrients, so it owns a high recycling value; but the food waste owns the high moisture content and perishable, which make it difficult in collectting, transporting and processing, if it disposaled Inappropriately may causes environmental pollution. Compared with the traditional processing methods, anaerobic digestion of food waste can not only solve the disposal problem, but also recycle energy and alleviate the energy crisis.To make the food waste harmless, less in amount and recyclable, and enhance the the test practicality, reducing the energy consumption of test, this experiment use the Upflow Anaerobic Sludge Blanket (UASB) reactor for the continuous anaerobic digestion of food waste pilot study under the normal temperature conditions, and provide the experimental basis for food waste anaerobic digestion of engineering. In this paper, we get the experiment materials from one of the Hunan University canteen, and experimental study on factors affecting the food waste anaerobic digestion process, also analyze the result:At beginning of the cultivation of anaerobic sludge and the domestication process, appropriately dosing bicarbonate (in this experiment by adding NaHCO3) to enhance the buffering capacity of the system, and resist volatile fatty acid excessive caused by operation load increased. Acidification of the sludge was recoveried by Chemical recovery act and physical recovery method.In the process of anaerobic digestion of food waste, with the increased of influent load, COD removal rate appeared a slight downward trend. From the overall perspective, COD removal rate were high, processing capacity of reactor can reach11.5gCOD/(L·d).The two reactor had good gas production performance, with improved of the influent load, gas production and methane production of two reactors were increased. The maximum gas production of two reactors, respectively were12.12L/d and11.27L/d, the corresponding methane production were6.43L/d and6.75L/d. The reactor effluent VFA concentration increased with the rise of the influent COD concentration, when the influent COD concentration is11500mg/L the two reactors effluent volatile fatty acid were11.09mmol/L and10.98mmol/L, if you would like to further improve the load, the stability of the system is running to be studied. In the process of anaerobic digestion of food waste, the basic reactor was maintained at6.88-7.91in pH. It showed that it is feasible in a certain volume of the organic load degradation of food waste, this experiment was carried out under normal temperature conditions, through the combination of the model’s derivation with the test date, the dynamic model of food waste degradation is established and it provides the experimental basis for engineering applications which food waste degradation at normal temperature conditions.