A Study On Dynamic Model Of Landfill Leachate Treated By Anaerobic Sequencing Batch Reactor

Leachate is a type of organic wastewater containing large amounts of pollutant with high concentration. And quantity and quality of leachate vary significantly with landfills and their ages. As a New high-rate anaerobic reactor,the Anaerobic Sequencing Batch reactor coule treat a wide range of organic wastewater in a large temperature range.But,the Anaerobic Sequencing Batch reactor also has its shortage,such as:effluent organic matter concentration is still high;greater impact on microbial toxic substances;susceptible to acidification.ect.The anaerobic reactor operator on the operation requirements of higher.It need to run the reactor for real-time monitoring of the situation and select the most appropriate way to adjust the operating parameters of the reactor. All of this need to establish a complete mathematical model.This requires the establishment of a comprehensive mathematical model, through the reactor at each phase of the simulation, operation control method of the best and timely adjustment of the reactor.Based on Monod equation, a dynamic model on Anaerobic Sequencing Batch reactor (ASBR)was developed in this paper. This model is composed by two parts:â‘ Acid bacteria and methanogenic bacteria in the dynamic process of growth and decay.The dynamic process simplified the microorganisms in anaerobic system as three genera, i.e., acidigens and methanogenswhose growth and decay processwere taken into account;â‘¡The processes of the physi-chemical equilibriums in anaerobic digestion.This process simplified the anaerobic digestion process into two subprocesses, i.e., acidification of carbohydrates and methane productionfrom volatile fat acid.The biochemical dynamics of physical and chemical equilibrium equations and simultaneous equations, thereby establishing a complete dynamic model of ASBR reactor.In this paper,according to different references provided by the kinetic parameters to determine the range parameter and the operational data of a lab-scale ASBR reactor with leachate during the 36th to 51st daywas used to estimate the main dynamic parameters for the previously developed dynamic model. This dynamic modelwas then used to simulate the performance of the same ASBR reactorThe results showed that this model could basically simulate the operational parameters as effluent COD, pH value in the reactor and effluent alkalinity.Under the condition when influent quality and operation parameterwere given, the model can predict effluent COD and VFA concentrations of ASBR reactor, internal pH value and change of alkalinity of the reactor, biogas yield and its composition.At the same time,simulation results and experimental results demonstrate that ammonia and nitrogen from water alkalinity and pH value on the water has a great influence.So influenting ammonia concentration to maintain the reactor for the pH value to ensure stability and prevent the acidification of the reactor system have an important significance.