Abstract:With the rapid development of economy and improvement of people’s living standard, aquaculture was developed rapidly over the past years. And a large amount of livestock wastewater was produced meanwhile. Thus effective treatment of livestock wastewater becomes the much urgent problem to be solved. Anaerobic treatment technology is recognized as one of the most promising wastewater treatment technologies in environmentally sustainable development. The design of anaerobic reactor is the key for developing anaerobic treatment technology of livestock wastewater. In order to describe and simulate the process of anaerobic reaction, guide the optimization of process parameters and design of reactor in the practical production, the kinetic model of livestock wastewater was established. The experiments were carried out in an external loop reactor. The orthogonal experiments with three factors and three levels were designed by taking temperature, matrix COD and pH value as factors. Temperature parameters were introduced to improve the Monod equation, and the dynamic models of matrix consumption and product formation were established. By linear and nonlinear regression, the model parameters and the corresponding dynamic equations were established, and the effects of reaction temperature and substrate concentration on reaction rate were revealed. The results showed that the reaction activation energy was very low, and the effect of temperature on reaction rate could be neglected. Temperature could affect the production rate of CH4 and CO2. The production of CO2 would be increased with the increase of temperature. The new livestock wastewater anaerobic reaction dynamics model could fit the experimental data well, which had positive significance for the development and design of new anaerobic reactor.
