Sharif Digital Repository

This research was done in order to test the capability of endemic microorganisms in treating hydro-carbonic pollutants found in the soil specimens of Assaluye industrial region. To find the optimum conditions for treating the contaminations, we tried several amounts of substrate as well as temperature and humidity. The total concentration of hydrocarbon compounds in polluted soil samples was measured by both infrared spectrometry and gas chromatography, in treatment process after extraction. The results show that, having 50mg substrate per 1kg of contaminated soil added and keeping humidity at 11%, in a 60-days course the level of initial pollution decreased by 60%. 10 degrees increase in... 

Petroleum based products are the major sources of energy for industry and daily life, With the development of social economy, the demands of the oil have increased dramatically. Petroleum hydrocarbons can cause environmental pollution during various stages of production, transportation, refining and use. Releases of petroleum products(e.g., gasoline, diesel, fuel oil) from aboveground and underground storage tanks or transport pipelines are the major causes of the environment pollution.The major constituents of petroleum hydrocarbons are biodegradable. Many soil microorganisms transform oil hydrocarbons into nontoxic compounds or mineralize them to inorganic compounds. In situ... 

With the current demands in alternative methods of energy production and increased utilization of existing energy sources, microbial fuel cells have become an important field of research. In a microbial fuel cell, organic and inorganic compounds can be oxidized by microbial catabolism at the anode to generate direct electricity. A kind of microbial fuel cell (MFC) is sediment microbial fuel cell (SMFC) consists of an anode electrode embedded in the anaerobic sediment and a cathode electrode suspended in the overlying aerobic water. microorganisms produce electrons by oxidation of organic or inorganic compounds in the sediment at anode electrode, while oxygen is reduced in the water by... 

Sustainable development requires the development and promotion of environmental management and a constant search for green technologies to treat a wide range of aquatic and terrestrial habitats contaminated by increasing anthropogenic activities. In this work we investigated the ability of four previously isolated fungi, BBRC 9057, BBRC 20020, BBRC 9058 and BBRC 9002, in degradation of polycyclic (PAHs) and the effect of UV irritation on fungi cell growth and degradation of PAHs. Also we studied the degradation of anthracene by thermophilic filamentous fungi in liquid and soil slurry bioreactor. Cell growth and anthracene degradation ability of BBRC 9057 increased 6.51 and 1.82 times rather... 

TPPB are characterized by a cell-containing aqueous phase, and an immiscible and biocompatible organic phase that partitions toxic/insoluble substrates to the cells base on their metabolic demand and the thermodynamic equilibrium of the system. Surface areas, Mass transfer coefficient, Hydrophobicity of polycyclic aromatic hydrocarbons (PAH) are considered as limitation in two phase partition bioreactors (TPPB). For solving of this challenge, in this project used solid particle for increment of mss transfer and surface area, and also solid particles can eliminate limitation of initial concentration of polycyclic aromatic hydrocarbon and ratio of aqueous/organic phases. Naphthalene is used as... 

Crude oil and petroleum products at the time of extraction, production and transportation cause serious contaminations in soil, water and environment. Biological methods have shown a promising effect for the cleanup of these hydrocarbon pollutants. Bioremediation employs the metabolic activity of microorganisms capable of using oil as their energy and carbon source. Biological methods are also less expensive than other cleanup technologies such as incineration and landfill. Large number of microbial stains have been discovered in nature, capable to degrade oil and petroleum products. Biological cleaning of oil contamination by microorganisms occurs naturally in the environment. It has been... 

Goal of this project was study of local microorganism ability in remediation of hydrocarbon contamination exists in contaminated soil around Sarkhun refinery.In first phase of this study, evaluation of bioremediation performance was done. Using a standard method in a 20 days period, the ability of local microorganism exists in contaminated soil was studied. In this study, 3 different nutrient ratios for 7 samples, 21 experimental samples, were used. Nutrient ratios as C:N:P were: 100:0:0, 100:5:1, and 100:9:1. Results showed that in this remediation period, minimum remediation efficiency in all samples with nutrients is 50% and also the best nutrient ration is 100:5:1. An empirical model was... 

When oil spill take place, it should be removed rapidly. For control of oil pollution, polymeric foams that absorb oil highly, can be used. These foams are polyurethane and polypropylene that float on water and absorb several times their own weight of crude oil. When a thin layer of crude oil remained on water, it couldn’t be separated by chemical and physical methods. In this cases biological methods will be best and suitable. Therefore absorption and biodegradation of oil spill are executed by immobilization of suitable microorganism on polyurethane foam. But current polyurethane foams aren’t biodegradable so this incompetence should be solved. Polyurethane foams compose of two basic... 

Soil and water pollution is one of the most common types of pollution in terrestrial and aquatic ecosystems. The development of mines and the oil and petrochemical industry on one hand and the non-compliance with environmental requirements on the other hand have caused large amounts of hydrocarbon pollutants and heavy metals to enter the environment in recent decades. Petroleum materials and heavy metals leak into the surrounding environment during drilling and extraction in oil sites and mines or during land and sea transportation, despite the measures taken to control their pollution. The conducted studies show that human industrial activities are the only cause of environmental pollution... 

Oil pollutants are among the important sources of pollution in countries with oil and gas industries such as Iran. Soil pollution by these pollutants is one of the environmental issues and hazards. All kinds of organic and inorganic pollutants in the soil may penetrate the underground water or enter the atmosphere in the form of gas, which respectively enters the food chain through absorption by plants or enter the body of living organisms through breathing. They include humans, which are a threat to the health and life of living beings. For example, many of these pollutions cause diseases such as cancer, suppression of the body's immune system, or even obesity; therefore, it is necessary to...