Sharif Digital Repository

Due to the large portion of organic fraction of municipal solid wastes in Iran, the needing for stabilization and treatment of this waste is obvious. An appropriate method for treatment of these wastes is anaerobic digestion. By skimming through open literature which are investigated about anaerobic bioreactors, declared that despite the benefits of thermophilic bioreactors over mesophilic ones, (more destruction of pathogens, more removal of volatile solids, more production of biogas and greater resilient to organic loading rate shocks) but because of more difficulties in controlling of thermophilic bioreactors, most studies have been done in mesophilic state. This motivated us to a deeper... 

The goal of this research is to optimize the parameters of a process through which it would be possible to separate and recovery a considerable portion of ammonia nitrogen available in anaerobic digestion effluent slurry. To achieve this goal, after completing the construction of batch setup (including anaerobic reactor and stripper) and after the digestion of (cow and poultry manure) , the experiments of separation on amounts 9, 10, 11 and 12 of pH and on temperature 14, 25, and 38 celsius degrees were done on digested slurry. Then, the resulting equations of the experimental outcome fitting were used in the optimization of parameters. The results showed that the amount of the parameters of... 

Anaerobic digestion is a useful process that is very important, addition to producing methane as energy source, it can be used for treatment of solid waste and sewage sludge. This process due to the presene of chemical and biological reactions and abundant chemical species, is very complicated and sensitive, so it is very unstable against any kind of change. as for the large importance of the process, we need control and optimization. In order to improving the performance of the process and increasing biogas and methane production, we should control and optimize the process. ADM1 is principal and the most accurate model for this process, a variety of reduced order models used to design... 

The best method for stabilizing sludge is anaerobic digestion, In addition to reducing the amount of volatile solids; it produces biogas, which can be considered as a sustainable energy source for wastewater treatment plants. However, the most important factor limiting the process of digestion is the sludge hydrolysis, the best way to increase the speed of hydrolysis is to pre-treatment the sludge before entering the digester; One of the most effective pretreatment methods is pre-treatment by ozone gas, This gas, which is highly unstable, quickly reacts with the wall of the bacterial cell and oxidizes it due to its high oxidizing properties And accelerates the process of sludge hydrolysis.... 

In this project, performance of anaerobic digestion of organic waste in liquid phase has been investigated in an experimental process. Thus, the objective of this study was to optimize the organic loading rates, temperature and mixing of anaerobic digestion to the treatment of municipal solid wastes. To achieve this, the pilot scale experiment was conducted in 70l, fully mixed reactor. The start-up process was established over a period of 2 months. Starting the digestion in two stages was done with two different feed stocks, in which the feed stock of the first stage was star and in the second stage vegetables were considered as the organic waste. Experiment was investigated in mesophilic... 

The objective of the present research, for the first time, was to configure a novel dynamic model to be applied in a general manner to simulate bioelectrochemical systems including microbial fuel cell and microbial electrolysis cell. Biochemical reactions engaged in organic substances degradation in both anolyte and biofilm were described by two anaerobic digestion models; Bernard’s anaerobic digestion model and ADM1. In addition, the bioelectrogenesis and electron transfer were modeled based on the direct electron transfer mechanism across the conductive biofilm. The biofilm simulation was established upon the one-dimensional distributions of substrates and microorganisms. In this study,... 

Nowdays much of the organic solid waste and wastewater is buried using centralized and traditional methods. This leads to many problems, including groundwater pollution, methane emissions into the atmosphere and rapid transmission of disease. In order to avoid these problems, using a decentralized approach can be a good solution. In this study, recovery of organic waste and wastewater of residential buildings using anaerobic digester as a decentralized way, have been examined. Using experiments, the optimum mass ratio of organic solid waste and wastewater is obtained as 80% and 20% respectively. Biogas production model is developed using mass balance and Balance of electrons in redox... 

With the growing development of urban communities and population, the demand for water and treated sewage water has grown significantly. The environmental damage of polluted water has resulted in passing of new and strict environmental laws on wastewater discharge recently. In the present research, a hybrid system involving a power, heat and cool cogeneration and a carbon dioxide capture system has been designed for a typical wastewater treatment plant. The plant is optimized from economic and environmental criteria. The anaerobic digester is modeled using the ADM1 model. The biogas is directed into the hydrogen sulfide removal filter to remove the impurities and into the heat exchanger to... 

In this project, function of anaerobic digestion of organic waste in liquid phase and treating the following sewage in biologic tower(trickling filter) has been investigated in an experimental process. Solid waste were supplied from sharif university restaurant and after weighting and classification is added to tanks which filled by 40% sludge and 60% water. For controlling the function of biologic tower, a control reactor were used. Retention time for digestion of solid waste is 40 day. First solid loading was 500g and 75g organic waste in main & control reactor equal to 5(kg solid waste)/( m^3.reactor.day) 1.3(kg TS)/( m^3.reactor.day) and were doubled in second loading. It seems that... 

Anaerobic digestion of waste and wastewater has attracted researchers’ attention due to its important effect on reducing greenhouse gas emissions and reducing the level of environmental pollution and production of methane as a renewable energy source. This process is highly sensitive and can become unstable due to the presence of complex biochemical reactions and containing various types of chemical in it. In order to understand and improve the performance of this process, modeling and design of an appropriate control strategy is needed. ADM1 is the most accurate model for this process which is used in this study to describe and simulate the anaerobic reactor. Constrained and unconstrained... 

Anaerobic digestion of waste and wastewater has attracted researchers’ attention due to its important effect on reducing greenhouse gas emissions and reducing the level of environmental pollution and production of methane as a renewable energy source. This process is highly sensitive and can become unstable due to the presence of complex biochemical reactions and containing various types of chemical in it. In order to understand and improve the performance of this process, modeling and design of an appropriate control strategy is needed. ADM1 is the most accurate model for this process which is used in this study to describe and simulate the anaerobic reactor. Constrained and unconstrained... 

Improper management and inefficient methods such as direct disposal to the environment to stabilize municipal solid waste and sewage sludge in addition to creating environmental problems due to the existence of food cycles, will also cause problems on human health. In this study, a hybrid system is modeled to produce value added in the form of energy and nutrients from a combination of food waste and secondary sewage sludge. This system has 3 subsystems, two-stage anaerobic digestion process that will be accompanied by the production of your bios (hydrogen + methane), the process of recovery of phosphorus from the sludge out of the digestion process and the system of simultaneous production... 

Industrial symbiosis(IS) is a promising approach toward sustainable development goals. Among common modeling techniques, agent-based modeling holds a special place in IS simulation due to its bottom-up nature. However, the role of essential technologies in supply chain of IS has been poorly studied in the literature. In this work, first, an agent-base model is developed based on economic and environmental incentives of IS stakeholders employing optimization and non-cooperative game theory. Then, essential technologies in each potential symbiotic relation are integrated into the model to investigate their impact. The result suggests, to facilitate IS through environmental policy making, on... 

Due to the high cost and destructive effects of fossil fuels, the biogas production as a renewable and environmentally friendly fuel attracted much attention. In this regard, several targets are considered in this research. First, in order to increase of biogas production yield and accelerating the rate limiting steps in anaerobic digestion of wheat straw (lignocellulosic feedstock), the effect of additives containing trace elements (Fe and Ni) in form of nanoparticles and their salts was investigated through batch experiments. The results showed that addition of nanoparticles or salts resulted in the increase of methane production rate during the first 4 days of experiments. Then, a...