Showing 6 results for Petroleum
A.a. Besalatpour, M.a. Hajabbasi, A.h. Khoshgoftarmanesh , M. Afyuni1,
Volume 12, Issue 44 (7-2008)
Abstract
Total petroleum hydrocarbon (TPH) contaminations in soils may be toxic to human, plants and cause groundwater contamination. To achieve maximum TpH- reduction and to establish successfull stable vegetation cover in phytoremediation method, various criteria must be considered to choose the plants carefully. In this study, germination and subsequent growth of seven plants were tested in three soils with different petroleum contamination levels. Contamination treatments consisted of C0 (uncontaminated soil), C1 (1:1 w/w, uncontaminated: contaminated soil) and C2 (1:3 w/w, uncontaminated: contaminated soil). The experimental design was completely randomized split plots with three replications per treatment. The results showed that the presence of TPH in the soil had no effect on seed germination of agropyron, white clover, sunflower and safflower although canola seedlings were sensitive to these compounds and failed to produce dry matter yield (DMY) at the end of trial period. In contrast, seed germination of canola, puccenillia and tall fescue decreased in the petroleum contaminated soils. No reduction was found in DMY of puccenillia in contaminated soils (C1 and C2 treatments) compared to control however, the presence of TPH proportional to the contamination levels, decreased dry weight of sunflower and safflower. This reduction in growth and dry weight for tall fescue and agropyron was also observed in C2 compared to C1 treatment. Therefore, it seems that though agropyron, white clover, sunflower and safflower germinated well and the presence of TPHs in the soil treatments had no effect on their seed germination, they grew poorly. In contrast, grasses had poor seed germination but their subsequent growth and establishment in the contaminated soils was acceptable for subsequent phytoremediation trials.
A.a. Besalatpour , M.a. Hajabbasi, V. Dorostkar , Gh. Torabi,
Volume 14, Issue 53 (10-2010)
Abstract
Presence of petroleum contaminants in soil may be toxic to human and organisms and act as a source of ground water contamination hence, remediation of these compounds from environment is vital. In this study, first the feasibility of remediation of two petroleum-contaminated soil samples around Tehran Oil Refinery (oil refinery landfill and agricultural soils) was assessed using landfarming technique during a four month experimental period. The elimination of total petroleum hydrocarbons (TPHs) from soils treated through landfarming technique was then investigated in the rhizosphere of agropyron and fescue. The results showed that microbial respiration increased due to landfarming processes in both soils. Urease activity in the landfarming treatment for agricultural soil was 21, 45, 26, and 23% higher than the control at the end of first to the 4th months of experiment, respectively. However, no significant differences were observed between the landfarming and control treatments for landfill soil at the end of experiment. Furthermore, about 50 and 57% reduction in TPH-concentration was observed in the landfarming treatment for landfill and agricultural soils at the end of experiment, respectively. In the phytoremediation study, presence of TPHs in both landfarming and control treatments reduced dry matter yield of the studied plants. Urease activity in the rhizosphere of fescue and agropyron was higher than in the unplanted soil. Degradation of petroleum-compounds in the landfill soil under landfarming treatment was more than 20 and 40% in the presence of fescue and agropyron, respectively. The influence of agropyron on TPH-removal from agricultural soil under the landfarming treatment was also higher than fescue.
M. Nouri, M. Homaee, M. Bybordi,
Volume 17, Issue 66 (2-2014)
Abstract
In order to assess hydraulics of LNAPLs in soil, the soil retention curves of petroleum and water were both determined through hanging column method. And, the hydraulic conductivity of petroleum and water were determined by steady head method. The water and petroleum hydraulic conductivities were 7.27 and 57.84 cm.day-1, respectively. The soil retention parameters were obtained based on van Genuchten, Brooks-Corey and Campbell models. In addition, the soil hydraulic conductivity for both fluids was predicted based on Mualem- Brooks-Corey, Burdine- Brooks-Corey, Mualem-van Genuchten and Campbell models. The accuracy assessment of models was performed by ME, RMSE, CD, EF and CRM. The results indicated that the magnitudes of the pore-size distribution parameters and the bubbling pressure parameters were reduced in NAPL-air system compared to water-air system. Due to unusual hydraulic behavior of petroleum and soil-petroleum interactions leading to remaining substantial petroleum content in porous media, more matric potential is needed to drain out petroleum from soils compared to water. Thus, soil provides more retention for petroleum at a given quantity of fluid. Owing to high amount of petroleum kinematic viscosity, the saturated soil hydraulic conductivity of petroleum was lower than that of water. However, soil hydraulic conductivity for petroleum was larger than water at more than 100 cm matric head.
M. Kermanpour, M. R. Mosaddeghi, M. Afyuni , M. A. Hajabassi,
Volume 19, Issue 73 (11-2015)
Abstract
Petroleum pollution is an important environmental issue in most of the countries especially those have an oil industry. This study was conducted to investigate the effect of petroleum pollution on soil water repellency and its relation to soil structural stability in Bakhtiardasht area, Isfahan. Polluted and adjacent non-polluted locations were selected to be representative in the green space around the Isfahan Oil Refinery. Soil water repellency was assessed using water drop penetration time (WDPT) in the polluted locations. Soil sample with least aggregates disturbance were collected and selected soil physical and chemical properties were measured. Soil structural stability was evaluated using the wet-sieving method and mechanically dispersible clay (MDC) structural stability indices of mean weight diameter (MWD) and geometric weight diameter (GMD) of aggregates and MDC were then calculated. Results showed that the positive effect of petroleum pollution on the MWD and GMD become significant. Negative impact of petroleum pollution on MDC was also significant. Increment of total petroleum hydrocarbons (TPHs) increased the soil water repellency. A positive correlation was observed between soil water repellency and GMD. However, TPHs concentrations greater than 6.4% decreased the MWD and GMD presumably due to anionic repulsion between clay particles and hydrocarbon functional groups. Although greater water repellency increased soil structural stability in the polluted locations when compared to control locations, however, diminished water retention of polluted soil has created an unfavorable condition for the green space in the area.
A. Foyouji Shahrezaei, M. A. Hajabbasi,
Volume 23, Issue 3 (12-2019)
Abstract
A well healthy environment can quietly affect the life quality and human community. In recent decades the need for and utilizing fossil had increased and thus the environmental pollutions including for soil has also increased. Petroleum contaminated soils are not suitable for agricultural, residential and social usage and cause economical, ecological and agricultural damage. To cope with this challenge, the use of additives such as carbon nanotubes has expanded to soil, but the use of these elements has raised concerns about their risk to biological processes and systems, such as effects on physiology and plant growth, and there have not been much studies on this issue. In order to investigate the interaction of soil petroleum pollution and carbon nanotubes on some plant characteristics such as wet mass, dry matter and plant length, seed and maize seedling were separately treated with 0, 10, 20 and 40 mg/l carbon nanotubes at the beginning. In pots containing soil with three levels of petroleum pollution, 2.43, 2.76 and 4.16% were cultivated with 3 replications. A completely randomized design was used in the form of factorial experiments. Wet mass, dry matter and length of shoot and root of plants were determined. The results showed that petroleum pollution had a negative effect on the growth characteristics. It was also observed that application of carbon nanotubes to maize (whether seed or seedling) depending on the concentration of these materials, could have different effects on plant growth parameters.
M. Mirjani, M. Soleimani, V. Salari,
Volume 24, Issue 1 (5-2020)
Abstract
Growing concerns about water pollution and its potentially harmful effects on human being have stimulated serious efforts to develop reliable biological monitoring techniques. The bioluminescent analysis is one of the most promising approaches for the biomonitoring of the environment, due to the sensitivity of the luminescent system to even micro quantities of the pollutants. The aim of the current study was to assess the petroleum compounds toxicity using Vibrio fischeri bacterium. The growth pattern of the bacterium was determined in photobacterium broth using the optical density measurement at 600 nm, which showed the optimum growth time of 16-18 hours after inoculation. In this research, the effects of environmental parameters such as temperature, pH and various concentrations of oil on the growth and luminescence of Vibrio fischeri were examined. The results revealed that the optimum growth conditions of the bacterium after 16 hours included the temperature of 25 °C and pH 7. Besides, the growth and luminescence intensity of Vibrio fischeri were a function of total petroleum hydrocarbon concentrations in the medium, which were significantly reduced in oil concentrations by more than 4% w/v. Therefore, the Vibrio fischeri could, therefore, have the potential for monitoring of petroleum pollutants in the aqueous media.