Sharif Digital Repository

Vulnerability of water and sewage infrastructure in Kish Island survey versus natural and unnatural threats. It is important to know what to do when crisis or unpredicted event occurs in the Island. Decision makers and master managers of the Island, as the main custodians make suitable and effective reactions and decisions so that the impact of threats is reduced to minimum. According to the threats, there are short term and long term solutions. These solutions can be applied when the Island is encountered with crisis  

Regarding the reduction of high qualified and accessible resources, the waste water treatments are accounted as one of the main challenges in environmental context. Surprisingly, with or without consideration of this issue can lead to play the crucial key in whether development or society retardation. With developing and being more sophisticated of waste water treatment technology and also rising the stringency of environmental constraint, approaching the optimum technology basis economics of scale is time consuming and complicated.Behind this concept, contribution of this study is twofold. The general approach of treatment is identified using AHP methodology in primary stage. After that, it... 

If wastewater is not properly treated, then the environment and human health can be negatively impacted. These impacts can include harm to fish and wildlife populations, oxygen depletion and contamination of drinking water. In the typical wastewater treatment process, the goal of primary, secondary and tertiary effluent treatment is to reduce or remove organic matter, solids, nutrients, disease-causing organisms and other pollutants from the treated wastewater before it is discharged to a body of water. Biological methods for wastewater treatment are much preferable for being more economical and environmentally friendly. Biological treatment of wastewater using algal-bacterial culture... 

Discharge of Raw wastewater or effluent of Treatment plants into the natural bodies of water, in the case of high nutrients may cause serious problems such as algae bloom which results in a reduction in concentration of dissolved oxygen. Among the nutrients, phosphorous is known as a limiting factor in growth and intensification (intensifier) of eutrophication. Therefore, elimination of phosphorus from wastewater prior to the discharge point is highly important. Phosphorus can be removed chemically as well as biologically. Chemical methods are known, efficient and reliable but Problems like operational and maintenance costs and chemical sludge production cause tendency to use biological... 

With the aim of making a pilot in two-steps, this thesis at 4 month accomplished. In first step, municipal sewage after passing of a septic tank loaded with daily 2 or 4m3/m2 rate to a vermi-filter while removal rate of COD was 83 and 64 percent respectively. In addition, the turbidity removal rate was 92 and 83 percent respectively. The results showed that vermi-filter is a suitable and cheap way for on-site wastewater treatment that is environmentally agreeable and odorless. Furthermore, the treated sewage is suitable for irrigate and flush tank usage. In the second step, for ground water denitrification, a synthetic wastewater with high nitrate, which nitrate is initially 13.5ppm NO3-N... 

Wastewater treatment plants play an important role within the urban water cycle in protecting receiving waters from untreated discharges. In the developed and developing countries, Energy consumption of these units are 3 and 5 % of the electrical energy demand, respectively. As far as sustainable development is concerned, not only the reduction of WWTP’s energy consumption is mandatory, but also these units should produce energy. To this end, several techniques are available namely: energy audits, replacement of equipment and improvement of process efficiency. Moreover, Energy can be generated by converting biogas -from anaerobic digesters- to heat and power. Todays, Biogas is well-known as... 

In recent years, access to clean energy sources is the major instruments for sustainable development. Limitation of energy resources and the problems resulting from the use of fossil fuels was caused attention to biomass in different countries as a stable source of renewable energy. Organic waste in municipal solid waste and domestic wastewater are biomasses that can be used as a raw material used in the production of energy. Practical studies show that quality and quantity of municipal solid waste to produce biogas and bioethanol in Iran is very appropriate. In this process, the household solid waste and wastewater are in the anaerobic digestion reactors and fermentation systems without any... 

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... 

This study aims to investigate the influence of important operational parameters on membrane fouling with the approach of fouling layers and to model these influences in the membrane bioreactor (MBR) for municipal wastewater treatment. At the first phase, 11 operational scenarios were executed using a pilot setup for identifying the system behavior and the optimal scenario. Protein and carbohydrate as the fouling components (SMP) and the transmembrane pressure (TMP) as the fouling criteria were measured in the tests. By studying the influence of operational parameters (sludge retention time (SRT), aeration rate and filtration mode), some useful results obtained for the next phase, including... 

This study aims to enhance biological nitrogen and phosphorus removal performance by the innovative carbon-based moving carriers (CBMC) and reveals the role of carrier characteristics on the nutrient removal efficiency. In this research, the new carriers with the advantages of both MBBR hybrid system and physicochemical properties of activated carbon were produced based on the recycling of waste materials for the first time via a chemical-thermal process. The analysis revealed that the specific surface area of the new carrier with a rough and highly porous structure was approximately 11.4 times that of the conventional MBBR carrier. This feature plus the other physicochemical properties of... 

Environmental and economic scarcity of resources are the most important challenges of industry sector. Iran confronted with lack of sufficient water resources and proper management and faces with drought and its environmental and economic consequences. It is a complicated challenge to provide the water demand without any damage to the ecosystem and it needs to do social, economic and environmental assessments. Wastewater treatment (water recycling) is an alternative option for supplying water demand. Wastewater treatment system (collecting, transportation to the treatment plant, wastewater treatment, and discharge) designed in order to solve hygienic and health issues in first place, but it... 

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... 

Micropollutants are a wide group of organic compounds that are detected in most compartments of the environment. Their environmental concentration is usually in the range of few ng/l to mg/l, but they remain biologically active even at such low concentrations; may be accumulated through the food chain, and pose a serious threat to the environment, fauna, and human health. Among micropollutants, pharmaceutical active compounds (PhACs) are of special concern. It is accepted that the main sources of PhACs in the environment are effluents from wastewater treatment plants (WWTPs), where conventional activated sludge processes are not able to degrade most of them. To address these concerns, the... 

A proper process selection has an important role in optimal operation of designed plants at exploitation time. The aim of this research is to provide software for the optimal process selection of municipal wastewater treatment plants in Iran which is a multi criteria optimization process. For this reason this project has been defined to establish a unique procedure for process selection aiming to help design engineers to find optimal process combinations. The main reasons of this case study include: special geology, the culture of people and economic conditions. Heretofore, numerous efforts have been done on optimal wastewater treatment process selection. But in most of them selection has... 

From the main factors causing an unpleasant odor can refer to indoles, askatels, mercaptans, some volatile organic compounds, sulfide hydrogen, ammonia, and the number of odor-causing compounds, which are also found in the wastewater facilities and sometimes produce unpleasant odors. Meanwhile, ammonia (Pungent and irritating odor) and sulfide hydrogen (colorless poisonous gas with the odor of rotten eggs) can be presented as major factors in sewage odor.
Several factors are involved in the foul-smelling hydrogen sulfide gas collection system and wastewater treatment. A few of them include numerous sewage pumping stations, selected the appropriate gradient in the collection system,...