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Enhanced Remediation of a Hydrocarbon Polluted Soil
J.U. Ebere,E.C. Wokoma and C.C.Wokocha
Research Journal of Environmental and Earth Sciences , 2011,
Abstract: The aim of this study was to use NPKs, saw dust and poultry manure as enhanced remediation techniques of a crude oil polluted soil, using a 42-day study period, time length. Polluted soil samples were collected at 0-10 cm depth from different polluted sites of the same area. Physicochemical parametres such as pottasium concentration and total hydrocarbon recorded a decrease at the 6th week, after application and lab testing. Total organic carbon recorded an increase on the 6th week, for treatments containing; PS+SD, PS+NPK and PS+PM. pH ranged between 5.21-10.1. The results suggest that a combination of ammendments in the right proportion w ould be effective in the remediation of crude oil polluted soil.
Remediation of petroleum hydrocarbon polluted systems: Exploiting the bioremediation strategies
AI Okoh, MR Trejo-Hernandez
African Journal of Biotechnology , 2006,
Abstract: The irrepressible quest for a cheap source of energy to meet the extensive global industrialization demand has expanded the frontiers of petroleum hydrocarbon exploration. These exploration activities amongst others often result in pollution of the environment, thus creating serious imbalance in the biotic and abiotic regimes of the ecosystem. Several remediation alternatives have been in use for the restoration of petroleum hydrocarbon polluted systems. In this paper, we present an overview of bioremediation alternative vis-à-vis other cleanup methods and its adaptations in various polluted systems.
Assessing the Effectiveness of Land farming in the Remediation of Hydrocarbon Polluted Soils in the Niger Delta, Nigeria
Mmom Prince Chinedu,T. Deekor
Research Journal of Applied Sciences, Engineering and Technology , 2010,
Abstract: Hydrocarbons pollution of soils has constituted environmental issues over the years. The biggest concern associated w ith hydrocarbon pollution in the environment is the risk to farmlands, fisheries and potable water supplies contamination. Several remediation techniques exist (Bioremediation and Non-bioremediation), which aim at reducing the hydrocarbon content of the polluted soil and water with their varying degrees of success. Thus land farming, one of the bioremediation remediation techniques is view ed as a more viable remediation options for hydrocarbon polluted soils. The study therefore was instituted to assess the effectiveness of land farming (Enhanced Natural Attenuation) in the remediation of hydrocarbon polluted sites in the Niger Delta. Soil samples from ten (10) sites polluted and remediated sites in the Niger Delta; that is five (5) samples each from the swampy and well drained sites and subjected to Laboratory analysis. The results were further analysed using both descriptive and inferential statistical tools of percentages, regression analysis and student t-test. The results of the soil analysis show 14.54 to 82.24% and 16.01 to 50.54% reductions in the TPH and PAH concentrations after land farming respectively. This shows high level of efficacy in the use of the Land farming as remediation technique. However, the efficacy varied between the swampy and well drained soils; reductions in the hydrocarbon levels of the soils in the water-logged or swamp areas were lower and slower than that of the well drained soils. This shows that the soil microbes were able to degrade the hydrocarbons faster in the well-drained soil probably because of the favourable soil conditions like pH, moisture, and nutrient. To ameliorate this problem, more effective way of bio-remediation for swamp area should be pursued like phyto-remediation; this is the use of higher plants to enhance the remediation of soils contaminated with recalcitrant organic compounds.
Studies on the diversity, abundance and succession of hydrocarbon utilizing micro organisms in tropical soil polluted with oily sludge
G Nkwelang, HFL Kamga, GE Nkeng, SP Antai
African Journal of Biotechnology , 2008,
Abstract: A research was carried out in a tropical region to study the population of hydrocarbon utilizers in soil polluted with oily sludge. Plots were prepared to receive treatments with neat and emulsified oily sludge. These plots were further treated with fertilizer and bioaugmented with a consortium of hydrocarbon utilizers for six months. Results obtained indicated that, the presence of oily sludge in soil caused the growth of diverse genera of oil degraders. The major genera of bacteria active in polluted soil were Pseudomonas, Bacillus and Acinetobacter, while fungal general were Aspergillus, Penicillium, and Mucor. Abundant microbial growth was observed during the first 60 days. Some organisms such as Pseudomonas, Bacillus, Penicillium, and Aspergillus were present in polluted soil throughout the experimental period, while others including Candida, Sporobolomyces and Rhizopus were found only during the first two months. Further analysis revealed that, succession of the hydrocarbon utilizers in polluted soil was subject to seasonal variations and depended primarily on the fraction of the oil being utilized at a specific time and also on the physiology of the micro organisms involved. In addition, the selective appearance and succession of hydrocarbon utilizers in the polluted soil were affected only by the presence of neat and emulsified oil in soil as compare to other treatment parameters. The practical implication of these findings suggests that reloading of oil in some treated plots could be carried out after the first 90 days. Molecular techniques are underway to provide a more comprehensive study on this successional trend.
Laboratory Scale Bioremediation of Petroleum Hydrocarbon – Polluted Mangrove Swamps in the Niger Delta Using Cow Dung
Orji, F. A.,Ibiene, A. A.,Dike, E. N.
Malaysian Journal of Microbiology , 2012,
Abstract: Aims: The aim of the study was to carry-out laboratory–scale bioremediation of petroleum hydrocarbon polluted mangrove swamps using cow dung as source of limiting of nutrients.Methodology and Results: In a 70 days study, the cow dung treated polluted soil had its total culturable hydrocarbon utilising bacterial/fungi, heterotrophic bacterial and fungal counts increased progressively from the 28th day to the 70th day. The control set- up showed very slight increment in its microbial growth. Alkaline pH was observed in all the treatments and control during the study period. The conductivity values of cow dung decreased progressively. In the cow dung treatment option, the nitrate concentration decreased from 35.44 mg/kg to 14.28 mg/kg. Phosphate concentration of cow dung option decreased from 25.41 mg/kg to 9.31mg/kg. The control had the nitrate decreased from 8.42 mg/kg to 6.98 mg/kg. Percentage total organic carbon (% TOC) in the cow dung option decreased from 4.06% to 0.96%. Control experiment had the % TOC decreased from 3.32% to 2.99%. Studies using Gas chromatographic analyses showed that 0%, 49.88%, and 69.85% of Total petroleum hydrocarbon (TPH) were lost at zero hour, 28th day and 70th day respectively in the cow dung option. In addition, in the control experimental set-up, 0%, 7.14% and 13.42% of TPH were lost at zero hour, 28th day and 70th day respectively.Conclusion, significance and impact of study: The use of organic nutrient sources such as cow dung has shown good promises in bioremediation of crude oil impacted Mangrove Swamps in the Niger Delta. The next line of action is to transfer the technology to pilot scale study.
Phytoremediation of Petroleum Hydrocarbons Sewage Sludge in Isfahan Refinery  [cached]
A.R. Melali,M.A. Hajabbasi,M. Afyuni,A. H. Khoshgoftarmanesh
Journal of Science and Technology of Agriculture and Natural Resources , 2011,
Abstract: The petroleum refinery sludge is an important source of environmental pollution. Burning and burying of the sludge may have adverse effects on environment and human health. Thus, other mechanisms for decreasing the toxic effects of hydrocarbon substances in the sludge must be used. In this study, Isfahan refinery sludge was dewatered, air dried and mixed by 0, 10, 20, 30 and 40% w/w ratio with two calcareous soils, viz., Mahmoud Abad (Typic Haplocalcids with clay texture) and Bagh Parandegan (Anthropic Torrifluvents with silty loam texture). Different mixtures of soil and sludge were farmed for 21 days and irrigated on a daily basis to field capacity. Then, 100 seeds of Tallfescue (Festuca arundinacea) and Agropyron were planted in polluted soils with 3 replicates in 3 kg pots for 5 months. Result showed that Tallfescue and Agropyron yields decreased in sludge contaminated treatments. In the 40% sludge treatment, Tallfescue decreased the total petroleum hydrocarbons content by 65 percent. The highest degradation for agropyron was in the 30% sludge treatment which showed about 55% reduction in total petroleum hydrocarbons. The 40% sludge treatment resulted in the minimum yields of root and shoot plants. The highest degradation of TPHs occurred in the Tallfescue rhizospher of 40% sludge. Maximum degradation of TPHs on the Agropyron rhizospher was in 30% sludge mixed with Bage parandegan soil, but maximum yield of plant was in 20% sludge. Our study shows that Tallfescue rhizospher is most effective for decreasing TPHs, and that the phytoremediation in soils with more clay can adsorb and fix the toxic components and then at higher levels of pollutions can let the plants grow.
Growth study on chrysene degraders isolated from polycyclic aromatic hydrocarbon polluted soils in Nigeria
I-E M Nwanna, GO George, IM Olusoji
African Journal of Biotechnology , 2006,
Abstract: Acinetobacter anitratus, Alcaligenes faecalis, Acinetobacter mallei and Micrococcus varians were isolated from polycyclic aromatic hydrocarbon polluted soils by enrichment culture using chrysene as sole carbon and energy source. Physiochemical evaluation revealed that these isolates grew well at a temperature range of 20 - 40°C, pH 6.0-8.0 but less tolerable to various salt concentrations except Micrococcus varians which grew at 1.0 to 7.5% NaCl. These organisms utilized chrysene, anthracene, naphthalene, crude oil, kerosene, diesel and engine oil as sole carbon source. None could utilize benzene, hexane, xylene, phenol and toluene as carbon sources. Growth study of the isolates on 0.1% (w/v) chrysene resulted in highest cell density of 8.8x107, 7.9x107, 6.3x106, 6.3x106 cfu/ml for A. anitratus, Alc. faecalis, A. mallei and M. varians, respectively. There was statistical significant difference (P< 0.05) in the growth of these organisms on chrysene as sole carbon and energy source when compared with non-chrysene control. This study indicates the potential of these hitherto unreported tropical bacterial strains as chrysene degraders and their use in biodegradation processes involving petrochemical products
Impact of substrate amendment on the polyaromatic hydrocarbon contents of a five month old waste engine oil polluted soil
B Ikhajiagbe, GO Anoliefo
African Journal of Environmental Science and Technology , 2011,
Abstract: The present study investigated the impact of substrate amendment on the bioremediation of waste engine oil-polluted soil. Top soil was collected randomly from a 50 × 50 m marked plot on a farmland, sun-dried and weighed. Ten kilogram’s of soil each was placed into perforated 25 L buckets. Waste engine oil (WEO) was prepared at 5 different levels of pollution: 0, 1.0, 2.5, 5.0, and 10.0% w/w, and poured into the measured soil, and thoroughly mixed. The entire set up was left under an open shade for 5 months without mechanically disturbing the soil, after which the polluted soil was amended with sawdust and left for a further 9 months. Significant reductions in polyaromatic hydrocarbon (PAH) content of soils over the experimental period were recorded. Total (100%) remediation of some PAH compounds (benzo[a]anthracene, benzo(a)pyrene, benzo[b]fluoranthene, benzo[g,h,i]perylene, benzo[k]fluoranthene, chrysene, dibenzo[a,h]anthracene, fluoranthene, fluorene, and indeno[1,2,3-c,d]pyrene) was recorded. Total PAH ranged from 1.10 to 6.35 mg/L in the substrate-amended treatment compared to a range of 25.45 to 456.99 mg/L in the unamended soil. Toxicity equivalencies (TEQ) in the unamended soils were generally higher than benchmark values, implying that the cleanup levels were not met. In the amended treatments, however, TEQs were presented for only benzo[a]pyrene (0.7284) in the control and indeno[123-c]pyrene (0.0272) in 2.5% w/w oil in soil treatment. TEQ’s of benzo[a]pyrene in the amended 5% w/w oil in soil treatment was 3.1252 mg/L, also higher than the benchmark TEQ of 1.0 mg/L.
Bioreactor-based bioremediation of hydrocarbon-polluted Niger Delta marine sediment, Nigeria
Chioma Blaise Chikere,Blaise Ositadinma Chikere,Gideon Chijioke Okpokwasili
3 Biotech , 2012, DOI: 10.1007/s13205-011-0030-8
Abstract: Crude oil-polluted marine sediment from Bonny River loading jetty Port Harcourt, Nigeria was treated in seven 2.5 l stirred-tank bioreactors designated BNPK, BNK5, BPD, BNO3, BUNa, BAUT, and BUK over a 56-day period. Five bioreactors were biostimulated with either K2HPO4, NH4NO3, (NH4)2SO4, NPK, urea or poultry droppings while unamended (BUNa) and heat-killed (BAUT) treatments were controls. For each bioreactor, 1 kg (wet weight) sediment amended with 1 l seawater were spiked with 20 ml and 20 mg of crude oil and anthracene which gave a total petroleum hydrocarbons (TPH) range of 106.4–116 ppm on day 0. Polycyclic aromatic hydrocarbons (PAH) in all spiked sediment slurry ranged from 96.6 to 104.4 ppm. TPH in each treatment was ≤14.9 ppm while PAH was ≤6.8 ppm by day 56. Treatment BNO3 recorded highest heterotrophic bacterial count (9.8 × 108 cfu/g) and hydrocarbon utilizers (1.15 × 108 cfu/g). By day 56, the percentages of biodegradation of PAHs, as measured with GC–FID were BNK5 (97.93%), BNPK (98.38%), BUK (98.82%), BUNa (98.13%), BAUT (93.08%), BPD (98.92%), and BNO3 (98.02%). BPD gave the highest degradation rate for PAH. TPH degradation rates were as follows: BNK5 (94.50%), BNPK (94.77%), BUK (94.10%), BUNa (94.77%), BAUT (75.04%), BPD (95.35%), BNO3 (95.54%). Fifty-six hydrocarbon utilizing bacterial isolates obtained were Micrococcus spp. 5 (9.62%), Staphylococcus spp. 3 (5.78%), Pseudomonas spp. 7 (13.46%), Citrobacter sp. 1 (1.92%), Klebsiella sp. 1 (1.92%), Corynebacterium spp. 5 (9.62%), Bacillus spp. 5 (9.62%), Rhodococcus spp. 7 (13.46%), Alcanivorax spp. 7 (13.46%), Alcaligenes sp. 1 (1.92%), Serratia spp. 2 (3.85%), Arthrobacter spp. 7 (13.46%), Nocardia spp. 2 (3.85%), Flavobacterium sp. 1 (1.92%), Escherichia sp. 1 (1.92%), Acinetobacter sp. 1 (1.92%), Proteus sp. 1 (1.92%) and unidentified bacteria 10 (17%). These results indicate that the marine sediment investigated is amenable to bioreactor-based bioremediation and that abiotic factors also could contribute to hydrocarbon attenuation as recorded in the heat-killed (BAUT) control.
Journal of Applied Phytotechnology in Environmental Sanitation , 2012,
Abstract: Industrial wastewaters containing petroleum hydrocarbon is highly toxic and posed a great danger especially to refinery nearby communities. Therefore, there is need for effective treatment before discharge. Natural process employing microorganisms is considered to be very effective and environmentally friendly method of decontamination. This research is mainly focused on the use of indigenous microbes in biodegradation of petroleum hydrocarbons in contaminated water. The wastewater was characterized for physicochemical, organics, inorganics and metallic parameters. The ability of Serratia mercescens, Bacillus subtilis, Micrococcus luteus, Bacillus cereus and biostimulated samples were studied for the hydrocarbon reduction from petroleum refinery wastewater. The performance of the system was measured by monitoring chemical oxygen demand (COD) reduction and increase in optical density (OD) of the flask cultured samples in Bushnell-Haas medium. Bacillus subtilis demonstrated high COD reduction of 56.19% while Micrococcus luteus reduced COD by 52.43%. Micrococcus showed higher growth in the Bushnell-Haas medium with the refinery wastewater as a sole carbon source.
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