The biological degradation of acetaldehyde in coastal seawater

Atrazine, a chlorinated s-triazine group of herbicide is one of the most widely used pesticides in the World. Due to its extensive use, long half-life and various toxic properties, it has very high environmental significance. Up to 22 mg l-1 of atrazine was found in ground water whereas permissible limit of atrazine is in ppb level in drinking water. As per Indian standard there should not be any pesticide present in drinking water. Among many other treatment processes available, Incineration, adsorption, chemical treatment, phytoremediation and biodegradation are the most commonly used ones. Biological degradation of atrazine depends upon various factors like the operating environment, external carbon and nitrogen sources, carbon/ nitrogen ratio (C/N), water content and the bacterial strain. Although, general atrazine degradation pathways are available, the specific pathways in specific conditions are not yet clearly defined. In this paper extensive review has been made on the occurrence of atrazine in surface and ground water bodies, probable sources and causes of its occurrence in water environment, the toxicity of atrazine on various living organisms and its removal by biological processes.

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The Malachite Green Biodegradation in Bioreactors on Various pH Domains

Revista de Chimie ◽

10.37358/rc.19.8.7472 ◽

2019 ◽

Vol 70 (8) ◽

pp. 2996-2999

Author(s):

Viorel Gheorghe ◽

Catalina Gabriela Gheorghe ◽

Andreea Bondarev ◽

Vasile Matei ◽

Mihaela Bombos

Keyword(s):

Malachite Green ◽

Contact Time ◽

Dominant Species ◽

Wastewater Treatment Plants ◽

Organic Substances ◽

Biological Degradation ◽

Growth Promoters ◽

Ph Values ◽

Biological Sludge ◽

Ph Range

In the experimental study was studied the malachite green colorant biodegradation in biological sludge with biological activity. The biodegradability tests were carried out in laboratory bioreactors, on aqueous solutions of green malachite contacted with microorganisms in which the dominant species is Paramecium caudatum, in a pH range between 8 and 12, temperatures in the ranges 25-350C, using pH neutralizing substances and biomass growth promoters. The colorant initial concentrations and those obtained after biological degradation depending on the contact time, at certain pH values, were established through UV-Vis spectrometry. The studies have shown the measure of possible biological degradation of some organic substances with extended uses, with largely aromatic structure, resistance to biodegradation of microorganisms, commonly used in wastewater treatment plants.

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Sludge minimization by disintegration at different wastewater treatment plants

Water Practice & Technology ◽

10.2166/wpt.2008.010 ◽

2008 ◽

Vol 3 (1) ◽

Author(s):

Luchien Luning ◽

Paul Roeleveld ◽

Victor W.M. Claessen

Keyword(s):

Organic Matter ◽

Wastewater Treatment ◽

Anaerobic Digestion ◽

Sewage Sludge ◽

New Technologies ◽

Wastewater Treatment Plants ◽

Treatment Plant ◽

Biological Degradation ◽

Ongoing Research ◽

Sludge Minimization

In recent years new technologies have been developed to improve the biological degradation of sewage sludge by anaerobic digestion. The paper describes the results of a demonstration of ultrasonic disintegration on the Dutch Wastewater Treatment Plant (WWTP) Land van Cuijk. The effect on the degradation of organic matter is presented, together with the effect on the dewatering characteristics. Recommendations are presented for establishing research conditions in which the effect of sludge disintegration can be determined in a more direct way that is less sensitive to changing conditions in the operation of the WWTP. These recommendations have been implemented in the ongoing research in the Netherlands supported by the National Institute for wastewater research (STOWA).

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Degradation of Oil by Land Disposal

Water Science & Technology ◽

10.2166/wst.1987.0048 ◽

1987 ◽

Vol 19 (8) ◽

pp. 99-105 ◽

Cited By ~ 3

Author(s):

G. Tesan ◽

D. Barbosa

Keyword(s):

Nutrient Availability ◽

Filter Cake ◽

Test Procedure ◽

Pilot Scale ◽

Effluent Treatment ◽

Biological Degradation ◽

Chemical Fertilizers ◽

Land Disposal ◽

Micro Organisms

The work presented consists of a test procedure applied at a pilot scale using soil as a biological degradation agent. The experiments described were carried out with oily residues considered as wastes difficult to degrade by other means. The tests were applied to filter cake with activated clay containing 40% oil and oily residues from re-refining of lubricants to give white oils and vaseline. The effect of the amount of moisture is evaluated using a mechanical stirrer to improve the interaction between the wastes and microorganisms. The following are also evaluated: nutrient availability; incorporation of micro-organisms into the soil; introduction of chemical fertilizers; and, injections of sludge from effluent treatment plants.

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Continuous Ozonation of Polycyclic Aromatic Hydrocarbons in Oil/Water-Emulsions and Biodegradation of Oxidation Products

Water Science & Technology ◽

10.2166/wst.1999.0581 ◽

1999 ◽

Vol 40 (4-5) ◽

pp. 107-114 ◽

Cited By ~ 9

Author(s):

A. Kornmüller ◽

U. Wiesmann

Keyword(s):

Polycyclic Aromatic Hydrocarbons ◽

Aromatic Hydrocarbons ◽

Biological Treatment ◽

Reaction Rate ◽

Oxidation Products ◽

Direct Reaction ◽

Biological Degradation ◽

Polycyclic Aromatic ◽

Oil Water ◽

Treatment Step

The continuous ozonation of polycyclic aromatic hydrocarbons (PAH) was studied in a two stage ozonation system followed by serobic biological degradation. The highly condensed PAH benzo(e)pyrene and benzo(k)fluoranthene were oxidized selectiely in synthetic oil/water-emulsions. The influence of the ozone mass transfer gas-liquid on the reaction rate of benzo(k)fluoranthene was studied for process optimization. The dissolved ozone concentration is influenced by temperature to a higher degree than the reaction rate of PAH. In dependence on pH, PAH oxidation occurs by a direct reaction with ozone inside the oil droplets. Two main ozonation products of benzo(e)pyrene were quantified at different retention times during ozonation and their transformation could be shown in the biological treatment step.

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