PRELIMINARY DATA REGARDING BIOREMEDIATION OF SOILS POLLUTED WITH PETROLEUM HYDROCARBONS BY USING CYCLODEXTRINS

The main characteristics of the pollution caused by refineries and petrochemical plants is that the source of pollution is active, most of the time, for a short period of time, but has an important intensity, the pollutiong agent being usualy made up of limited pretoleum fractions. Also, in most of tha cases of accidental spills of petroleum products, the affected soil surface is much smaller than the contaminated surface of the first aquifer encountered by the pollution front. The crude oil resulting from the extraction, having a complex composition, acts on the soil depending on the amount, composition and properties of the organic and inorganic components contained. β-Cyclodextrin is a chemical substance with the molecular formula C42H70O35. Cyclodextrins were the first compounds studied in terms of complexation behaviour and catalytic properties, the objective being to mimic enzymes. The paper presents data concerning the soil physical, chemical and biological characteristics and chemical characteristics of crude oil that will be used in the Greenhouse experiment. Also, in the paper is achieved the state of the art for β-cyclodextrins used in bioremediation of soils polluted with petroleum hydrocarbons

STEEL SLAG-AMENDMENT FOR ACIDIC SOILS

Acidic soils are soils that have a pH less than 6,5. There are several ways to raisethe pH of acidic soils, the addition of amendments is one of them.The steel slag can be an effective liming material in the favorable soil conditions forproductive plant growth; it can be used as acidic soils amendment considering the high contents of Ca and Mg.To find out if the soil needs modification, have it tested and also should take intoaccount the soil test recommendations to apply the steel slag as amendment

THE INFLUENCE OF AN INDUSTRIAL SLAG ON THE MACROELEMENTS CONTENT IN THE SOIL

To maintain the quality of the soil it is required its use according the characteristics it has. This implies the inclusion on the appropriate use of any kind of waste, nutrients and pesticides management; improve physical and chemical characteristics, to avoid pollution. The ability of steel slag to improve the characteristics of acidic soils may be explained by the high content of calcium and magnesium. The paper describes the changes that occurred with regard to existing macroelements in soil as a result of using different doses of steel slag (0%; 0.1%; 0.2%; 0.3%; 0.4%; 0.5%) for the purpose of amending the soil.Macroelements such as nitrogen, phosphorus and potassium, as well as organic carbon content are presented. Changes in the total nitrogen content and soluble potassium content were strongly influenced as a result of treatment

Bioremediation Potential of Native Hydrocarbons Degrading Bacteria in Crude Oil Polluted Soil

Bioremediation of crude oil contaminated soil is an effective process to clean petroleum pollutants from the environment. Crude oil bioremediation of soils is limited by the bacteria activity in degrading the spills hydrocarbons. Native crude oil degrading bacteria were isolated from different crude oil polluted soils. The isolated bacteria belong to the genera Pseudomonas, Mycobacterium, Arthrobacter and Bacillus. A natural biodegradable product and bacterial inoculum were used for total petroleum hydrocarbon (TPH) removal from an artificial polluted soil. For soil polluted with 5% crude oil, the bacterial top, including those placed in the soil by inoculation was 30 days after impact, respectively 7 days after inoculum application, while in soil polluted with 10% crude oil,  multiplication top of bacteria was observed in the determination made at 45 days after impact and 21 days after inoculum application, showing once again how necessary is for microorganisms habituation and adaptation to environment being a function of pollutant concentration. The microorganisms inoculated showed a slight adaptability in soil polluted with 5% crude oil, but complete inhibition in the first 30 days of experiment at 10% crude oil

THE DIVERSITY OF HETEROTROPHIC BACTERIAL MICROFLORA IN SOIL POLLUTED WITH CRUDE OIL AND DIFFERENT TREATMENTS

Petroleum hydrocarbon pollution is one of the main environmental problems, not only bythe important amounts released but also because of their toxicity. It is known that the mainmicroorganisms consuming petroleum hydrocarbons are bacteria. The present researchwork reports the diversity of microrganis from crude oil polluted soil been treated with anatural biodegradable product and bacterial inoculum. The bacterial inoculum was used toenrich indigenous microbes to enhance biodegradation rate. In soil excessively polluted with crude oil, bacterial population size in conditioned variant with Ecosol maximum dose (1%) presented values comparable to those of inoculated variants, demonstrating the protective and stimulation effect of soil bacteria, including those involved in the degradation of petroleum hydrocarbons exercised by organic compound applied Ecosol

A review on different bioremediation technologies for soil polluted with petroleum hydrocarbons

Crude oil and its derivates now has become a threat to environment due to extraction and transportation. Accidental oil spills occur regularly at many locations throughout the world. Contamination / pollution of soil with petroleum hydrocarbons has become a serious problem. Various physical, chemical and biological remediation strategies have been used to restore polluted soils. For bioremediation technology application, it is necessary to know the optimizing ways of the biodegradation process. Even though cost the of soil decontamination is roughly similar in many ways, more and more of pollution research is directed to biotechnological methods based on the ability of microorganisms to degrade certain pollutants under both natural conditions and through anthropogenic intervention meant to shorten the time of ecological reconstruction of polluted sites. Bioremediation can be divided into two basic types: natural attenuation, which can be applied when the natural conditions are suitable for the performance of bioremediation without human intervention, and engineered bioremediation, which is used when is necessary to add substances that stimulate microorganisms. Soil bioremediation technologies could be in situ or ex situ. As bioremediation technologies in situ cand be applied: biostimulation, bioaugmentation, bioventing, stimulation with surfactans, phytoremediation, use of agricultural land, natural attenuation, biobubbling, cometabolism. Ex situ bioremediation technologies could be achieved by bioreactors, hovering the land, biopile, composting

STEEL SLAG, A SUBSTITUTE OF LIMING MATERIALS IN AGRICULTURE

Regular application of amendments and fertilizers in required doses causes significant and lasting chemical changes in the soil, in relation with the degree of success of crop production. Steel slag is a highly alkaline material considered a by-product of the steelmaking process. This material is used in many different applications including the amendment for acid soils. Amendment is a practice commonly used for rapid elimination of problems of soil acidification. As a product applied in agriculture, the steel slag has been studied in many parts of the world somewhat with satisfactory results. In some European countries, researches have shown an improvement in acid soil properties. The ability of the steel slag to improve the acidity of the soil can be explained by the high content of CaO and MgO and Al2O3 low. When a liming material such as limestone or steel slag is evaluated, it is compare to calcium carbonate, and its neutralizing value is called the Calcium Carbonate Equivalent (CCE) value. Application of amendments, including by-products such as steel slag can restore soil quality by balancing the pH value, organic matter intake, increasing water retention capacity, reducing compaction, etc. For reasons of environmental protection, steel slag properties should always be tested given the wide variety in terms of their physical and chemical indicators

AN ASSESSMENT OF THE EFFECTS OF CRUDE OIL POLLUTION ON SOIL PROPERTIES

Pollution caused by crude oil is the most prevalent problem in the environment. The release of crude oil into theenvironment by oil spills is receiving worldwide attention. The effect of crude oil pollution on soil properties wasinvestigated by achieving a case study in Perisoru, Braila County. It has been achieved a profile until 120 cm and soilsamples were collected according to the methodology and analyzed for some physical and chemical properties. In caseof physical analysis, the values obtained for granulometric fractions were not influenced by the presence of crude oil.Results obtained showed variation in chemical properties of soil. Organic carbon increased from 2.23% for anunpolluted soil to 5.51% in polluted soil. C/N ratios increased from 13.01 for an unpolluted soil to 20.54 in pollutedsoil. Mobile phosphorous and potassium registered in polluted soil similar values with the one characteristic forunpolluted soil. Crude oil at high pollution levels inhibited the growth of crops

The influence of heavy metals on soil chemical characteristics from Copşa mică

The main pollution source in Sibiu is represented by the continued emissions of particulate matter and sediment containing heavy metals from S.C. Sometra S.A. located in Copsa Mica. High metal concentrations in the environment have widely ranging impacts on soils, plants and animals. Early 90s, polluted area stretched along the Târnava Mare valley, from Dumbrăveni town in the East, to Blaj in the West, and bordered to the north by Smig and Cetatea de Balta localities and in the southern part by Mihăileni, Șeica Mare and Cenade localities. Investigation area covered Târnava Mare Valley (upstream and downstream of Copsa Mica), between Tîrnava (upstream) and Micasasa (downstream) localities. Also, it have been done research in the valley slopes area. There were collected 30 soil samples on 0-20 cm depth (or Ap horizon), inside SOMETRA S.A. company and in the immediate vicinity, to obtain analytical data to characterize the dominant soils in the area and determine the pollutants content accumulated in the soil, especially on surface horizon and spread throughout the existing environmental conditions; laboratory tests on some chemical characteristics were achieved in ICPA Bucharest laboratories. In the investigated area formed a coating of diverse soil composed of terms belonging to four soils classes: Protisoils, Luvisoils, Hydrisoils, Antrisoils. Soils identified were classified according to Romanian System of Soil Taxonomy. The paper presents the chemical characteristics (soil reaction, organic matter content and total nitrogen and phosphorus and potassium supply mobile) of soil sampled from Copsa Mica. Soil samples collected from the enterprise influence area have a soil reaction neutral to weak alkaline. Regarding the contents of humus, total nitrogen, phosphorus and potassium are very low and low cell all the soil samples collected in the area

PHYTOEXTRACTION IN AN ARTIFICIAL SOIL POLLUTED WITH LEAD. THIRD EXPERIMENTAL CYCLE

This study concerns the research relating lead mobilization from artificially pollutedsoil by using EDTA ligand (ethylene diamine tetra acetic acid).Experimental research in Green House were designed to check the reproducibilityof analysed parameters on the selected plant (maize) and the conclusions of thepreliminary test laboratory experiments.The checking consisted in two experiments achievement with 2 degrees ofartificialloading soil with Pb: 1000 mg Pb/kg soil and concentration of EDTA in ratio Ligand/Leadbetween 0 and 0.5 and 2000 mg Pb / kg soil and ratio Ligand/Lead between 0 and 0.4 and three growing cycles (Cycle 1, Cycle 2 - residual effect, Cycle 3 - residual effect).The paper will present experimental results obtained in Cycle 3, remanent effect