Sharif Digital Repository

Different strategies for the treatment and disposal of petroleum and biological sludge found in the treatment and reuse unit of Arak Petroleum Refinery have been studied in the present study. To this end, the resources found in the literature corresponding to the different fields of sludge treatment were studied and a summary of them which was required by this research was mentioned in the thesis. Considering the problems bound to the wastewater treatment unit of this refinery plant and the previous studies, two completely separate strategies were devised. The first one concerns petroleum and biological sludge being produced continuously. The method of aerobic fixation of petroleum sludge by... 

In the present study , operation of a laboratory scale sequencing batch reactor (SBR) was evaluated to treatment of synthetic wastewaters containing ethylene glycol. Studies carried out with a plexiglass bioreactor whith effective volume of 18 lit.Aeration was supplied via two air diffusers that set at the bottom of the reactor. Synthestic wastewater containing ethylene glycol and molasses as carbon source and other nutrient such as diammonium hydrogen phosphate as phosphor source and urea as nitrogen source for biological activities was composed at the laboratory. To optimization of this reactor three parameters – aeration time, chemical oxygen demand and sudden change in arganic loading... 

In this study biological denitrification method by moving bed biofilm reactor is investigated. The main advantage of MBBR reactor is due to their capacity for high removal rates and low operational problems such as clogging. Two MBBRs in series with 3 liter volume each, were designed in experimental set up and used in this research. Nitrification reactor worked under aerobic conditions and denitrification reactor operated under anaerobic conditions. Methanol was used as carbon source in the reactors throughout the study. Fifty percent of each reactor volume was occupied with KMT1 packing. To finding the optimum nitrate loading rate, the concentration of ammonium and nitrate were changed from... 

In this research the performance of the Moving Bed Biofilm Rector (MBBR) in different amounts of dissolved oxygen (DO) was investigated. Reactor with a useful volume of 15 liters was used in this study. In order to obtain optimum oxygen concentration, stayed at 6, 10 and 15 hours, and at different levels of dissolved oxygen in the range 0.5 -6 mg/lit, the amount of organic material was removed respectively. Also, in two different aeration intensity of 3.5 and 5.5 liters per minute at different values of e% (percentage of filling of media) the mass transfer coefficient values were obtained. When the aeration intensity increases from 3.5 to 5.5 liters per minute, and the percentage of 40%... 

Discharging wastewater effluents to water bodies has many detrimental impacts on water quality. Thus, to prevent issues such as eutrophication and oxygen depletion, nitrogen removal is often required in wastewater treatment plants. Biological nitrification and denitrification, in comparison to physical and chemical methods, is more cost-effective and environmentally friendly, and this makes it one of the most commonly used approaches for nitrogen removal. In this work, nitrification and denitrification process and the effect of sulphate on this process is studied in a moving bed biofilm reactor (MBBR). The method used is modified LUDZACK-ETTINGER (MLE) which has an initial denitrification... 

Spent Caustic is the waste resulting from scrubbing of hydrocarbon streams with caustic solution. A thorough research on wastewater treatment to be performed at Tehran Oil Refinery in order to eliminate acid gases such as CO2 and H2S from LPG obtained from scrubbing given the fact that these gases are not eco-friendly, and the current systems of wastewater treatment are inefficient. Therefore, after investigating different methods used in Spent Caustic treatment, WAO method has been chosen to treat the wastewater at Tehran Oil Refinery. In this method, wastewater is oxidized with air at high temperature and pressure to reduce its COD. However, its high cost and operational difficulty of... 

Activated carbon, as an adsorbent with a high adsorption capacity and low cost, has many applications in liquid and gas adsorption processes. Among the adsorption of liquid phase, there are examples of drinking water purification, wastewater treatment, food industry, brewery, chemical separation (acids, amines, glycerin and glycols), enzymes ... and in adsorption from the gas phase there are examples of removing toxic compounds Containing sulfur and recycling sulfur, purifying biogas, use in gas masks, etc. Various materials can be used as raw material to make activated carbon. Materials such as walnut, almonds, coconut, pine, corn, etc. In this thesis, a feasibility study on the production... 

Activated Carbon as a highly efficient and low price absorbent has manifold functions in separation and absorption processes in liquid or gas phases. These applications in liquid phase include bleaching in sugar syrup, water and wastewater treatment and in gas phase utilizing them in gas masks and solvent recycling process. Wide variety of base materials could be used to produce activated carbon. For instance rare cellulose materials -wood, coconut shell, Pyrenees and agricultural wastes-, carbon materials-coal, petroleum coke, tar- and polymer materials- tires and plastics wastes- could be mentioned. In this thesis, feasibility of producing activated carbon based on using walnut, almond... 

Pharmaceutical waste has attracted considerable attention, in the Past two decades. These pollutants had not previously been detected in the environment. In fact, the concentration of pharmaceuticals became a matter of concern after the increase in the production and consumption of drugs. Nowadays, considering their higher consumption and more developed detection technologies, they are found in waste water, treated water, rivers, etc. The purpose of this research is to study treatment of a Synthetic waste water contaminated by Diclofenac and Ibuprofen in a Moving Bed Biofilm Reactor. An aerobic Moving Bed Biofilm Reactor (MBBR) with the volume of 8.5 liters and Kaldness packing filling ratio... 

Large amounts of Nitrogen and Phosphorous in municipal and industrial wastewater result in Eutrophication and many diseases in human. Nowadays, various methods have been used to remove Nitrogen and Phosphorous from wastewater. Besides Physical and Chemical methods, Biological approaches are utilized based on Biological Nutrient Removal (BNR) Systems. One of the most important and practical processes of these systems is Modified Bardenpho, which contain 5 stages and used for Nitrogen and Phosphorous Removal with high efficiency. In this thesis, we used Modified Bardenpho Process for removing nutrients. This method has 5 Moving Bed Biofilm Reactor (MBBR) which are respectively, anaerobic... 

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... 

Given that the most polluting industries in the country there. A suitable treatment system for degradation of these compounds is necessary unless unexpected effect on environment will occur.Moving Bed Biofilm Reactor (MBBR) was developed to adopt the best features of the activated sludge process as well as those of the biofilter processes. MBBR has biomass growth on carriers that move freely in the water volume of the reactor. High surface area of carriers make a good condition for biomass attached growth. This system has had good operation in the urban and some industrial wastewaters.In this study, four reactor volume of approximately 16 litr and 6, respectively, in the aerobic, anoxic... 

In this study, the biological nitrogen removal process from a wastewater with high COD and TKN concentration was investigated in a hybrid reactor. In order to remove nitrogen completely with pre-denitrification process, both moving bed biofilm system and fixed bed biofilm system with pumice stone, were used in a single reactor (volume is 16 l). Moving bed biofilm and fixed bed biofilm systems were considered in sequence, as aerobic and anoxic parts of the reactor. 35% of the aerobic volume was occupied with plastic carriers and 70% of the anoxic volume was occupied with pumice stone with an average diameter of 30mm. Experiments were done in 7 runs, for total hydraulic retention times of 30,... 

Phenolic compounds are hazardous pollutants that are released into environment through wastewater discharges from variety of industries. Although good biodegradability has been reported at low concentrations, but at higher concentrations phenols are known to be antibacterial. In this study the Membrane Biological Reactor (MBR) with submerged hallow fiber membrane was operated at 25±2 ºC and pH=7.5±0.5 to treat a synthetic wastewater containing high phenol concentration (up to 5.9 g/l). Removal efficiency of phenol and COD were evaluated at four various “Hydraulic Retention Times” (HRT) of 24, 12, 8 and 4 hours. To test the tolerance of the bioreactor to phenol concentration various loading... 

In recent years,because of increasing problems that result from water shortage ,using of wastewater treated by high quality and entering them to water cycle is considered more than past.Large amount of waste waterare produced through cooling towers in industries per a day .Therefore ,cooling tower’s blow down is a most important source for reclamation and reuse of water .The purpose of this project was investigation ofefficiency of submerged aerated filter for treating low organic simulated blowdown water as a feed . The experimental unit consisted of 8/5 L filled with 70 percent of propylene media . After obtaining steady –state condition ,The SAF reactor was tested under... 

Atrazine is widely used in the agriculture as an herbicide. Due to its high mobility, Atrazine leaks into the groundwater, surface waters, and drinking water wells. Many physical and chemical methods have been suggested for removing Atrazine from aquatic environments. However, these methods are very costly, have many performance problems, produce a lot of toxic intermediates which are very harmful and dangerous, and cannot completely mineralize Atrazine. In this study, biodegradation of Atrazine by microbial consortium was evaluated in the aquatic environment. In order to assess the Atrazine removal from the aquatic environment, Fixed-Bed biofilm reactor and Moving Bed Biofilm Reactor were... 

Discharging treated or raw waste water in to surface water may cause lots of serious problems, including growth of algae, as a result of the presence of nutrients in waste water.algae decrease the concentration of dissolve oxygen in water.phosphorus removal from waste water is of absolute necessity. according to the standards set by the environmental organization, discharge the untreated waster water in to the surface water is not allowed. on the other hand, given manager facilities of deprived area,effort is channeled to reach the desired result through designing the simplest treatment systems. anaerobic-aerobic systems have remarkably been used for many years in the treatment of urban and... 

In recent years, utilization of hybrid attached and suspended growth system for modification of conventional activated sludge systems has attracted a lot of attentions. Nowadays, with development of urban areas and also introducing new emerging contaminants and as a result an increase in the influent loading of wastewater treatment facilities, the importance of upgrading and retrofitting available facilities have been highlighted. Conversion of Sequencing Batch Reactors to Sequencing Batch Biofilm Reactors is a viable solution for overcoming these problems. Eventhough several researches have been conducted on removal of different contaminants through these systems, the information about the... 

Textile industry is one of the biggest consumers of water in the world. Effluents of textile industry ordinarily have huge rate of dye compounds which are toxic and persistent in environment. In case which they did not treat and discharged in the environment, they can create cancer, poisoning and etc. Finding efficient, economic and fast method for treating of these effluents is an important factor on the management. Combination of ultrafiltration membrane and reverse osmosis processes, has taken into consideration as an efficient and fast method of treatment of textile effluents in recent years. One of the fundamental problems of this process is the high costs of operation and chemical... 

Heavy metals such as lead, chromium, nickel are considered as environmental pollutants. These substances are highly toxic and dangerous to humans and other organisms at low concentrations and many problems are caused by them. Chromium belongs to the group of heavy and toxic metals. Form 6-valent chromium for humans is considered a definite carcinogen and also creates other problems. One common method of chromium removal is chemical precipitation which caused a large volume of waste. Other methods such as ion exchange, solvent extraction, reverse osmosis and biological methods are used to remove chromium. Adsorption is another effective method with very few disadvantages compared to other...