Introduction to the AARSE2016 Special Issue of the South African Journal of Geomatics

No Abstrac

Медико-социальная экспертиза

МЕДИКО-СОЦИАЛЬНАЯ ЭКСПЕРТИЗАОРГАНИЗАЦИЯ ЗДРАВООХРАНЕНИЯУЧЕБНО-МЕТОДИЧЕСКИЕ ПОСОБИЯСодержатся современные материалы по вопросам медико-социальной экспертизы. Предназначено для проведения лабораторных занятий

Biosurfactant facilitated emulsification and electro-osmotic recovery of oil from petrochemical contaminated soil

Petroleum industries are burdened with the problem of handling petroleum products, petroleum waste products and refinery byproducts such as large quantities of oil waste. Improper management of these products and their wastes present an environment hazard when they end up in the atmosphere, water and land due to their hazardous constituents. An evaluation to determine the possibility of enhancing the electrokinetic process by application of a biosurfactant producing strain for remediation of petroleum contaminated soil through oil recovery and hydrocarbon degradation was studied at a bench scale. A DC powered electrokinetic reactor consisting of electrode/electrolyte compartments and a medium chamber was used under voltage variations of 10 V and 30 V with an electrode spacing of 185 mm. Biosurfactant with its producing microbes and biosurfactant free cells were introduced in the soil chamber after which the reactor was left to run for 10 days under the electric field. The technology was able to achieve the highest oil recovery of 75.15 % from the soil in 96 hours at 30 V. The microorganisms were able to survive under the electric field there by leading to further reduction of the carbon content in the reactor.The National Research Foundationhttp://www.aidic.it/cetam2020Chemical Engineerin

Evaluation of the toxicity of a rhamnolipid biosurfactant for its application in the optimization of the bio-electrokinetic remediation of petrochemical contaminated soil

The combination of bioremediation, biosurfactants and electrokinetic remediation as a hybrid system was evaluated for the possibility of enhancing the removal of petrochemical hydrocarbons from contaminated soil as a sustainable and effective replacement for ineffective conventional remediation methods in an optimized manner. To begin with, the toxicity of the biosurfactant was determined by examining the effect of the biosurfactant on plant growth and microbial growth. The independent effect of biosurfactant concentration, voltage, the distance between electrodes and multifactor interactions on the bio-electrokinetic remediation of petrochemical contaminated soil using a bench-scale electrokinetic system were then evaluated. The results revealed that the rhamnolipid biosurfactant did not have any observable inhibition effects on the growth of the test bacteria in 5 days since the growth under test solutions of 0 mg/L, 10 mg/L, 50 mg/L and 100 mg/L did not have any significant differences. On the other hand, the biosurfactant affected root elongation and germination of the three test vegetables. Still, SDS had more substantial adverse effects represented by extremely low values of germination index as compared to the biosurfactant. The bio-electrokinetic remediation of soil revealed that a combination of the highest voltage of 30 V, the lowest electrode spacing of 185 mm and the highest biosurfactant concentration of 84 g/L had the highest microbial growth of 11.52 CFU/mL and hydrocarbon removal of 92% as compared to other configuration combinations. Microbial growth and hydrocarbon removal were mainly affected by voltage and biosurfactant concentration as the independent variables.https://www.sciencedirect.com/journal/cleaner-engineering-and-technologyhj2023Chemical Engineerin