Activated sludge is a biological floc composed of microorganisms, organics, and inorganics and plays an important role in wastewater treatment. The pH of an activated sludge suspension determines the acid – base behaviour and the charge of the microorganisms in water. In the present study, the...

It is well known that chlorine and its compounds, traditionally utilized for water and wastewater disinfection, react with some organic matter to form undesirable by-products, hazardous to human health, known as Disinfection By-Products (DBPs). In many countries very stringent limits for...

The purpose of the present study is to investigate the single and joint effect of zinc and copper to the growth pattern of the metal tolerant species of Arthrobacter sp. JM018. The results showed that, both, Zn and Cu at concentrations between 1 to 10 μM stimulated the growth of the above...

Trichloroethylene (TCE) is found in all mediums of environment in varying concentrations. Over the past 25 years, many engineered systems have been devised for its complete and sustainable degradation. This study reviews the environmental factors that influence the TCE pollution in environment and...

Olive oil mill solid residue (OMSR) is the solid waste generated during olive oil production process in three-phase olive mills. It consists of the remaining pulp of olive processing after the extraction of oil, as well as the cracked seeds of the olive fruits, containing thus mainly lignocellulose...

The goal of every solar saltworks with seawater intake--continuous and economic production of high quality salt (sodium chloride) at design capacity—requires ability to simultaneously manage and coordinate physical systems with biological systems in the concentrating and crystallizing ponds. This...

Industria Salinera de Yucatan S.A. de C.V. (ISYSA) has its operation of primary production of salt by solar evaporation in Las Coloradas, Yucatan, Mexico, in the coast the northwest of the Yucatan Peninsula. One of the disadvantages of this location is the presence of extreme climatologic phenomena...

Sites co-contaminated with organic and metal pollutants are common and considered to be a more complex problem, as the two components often have a synergistic effect on cytotoxicity. This study investigated the dissipation mechnisms for pyrene in cadmium co-contaminated soil in which maize (ZEA MAYS...

The introduction to the European Market of biodiesel blends along with the minimization of the sulphur content in automotive diesel has rejuvenated the research interest on the microbial stability of diesel fuel. Several microorganisms are able to metabolize hydrocarbons contained in conventional...

Various pollutants (e.g. boron and hexavalent chromium) are introduced into the aquatic environment from a variety of industrial operations causing damages to environment and affecting human health. Boron in irrigation water is of particular interest because it can have beneficial or toxic effect on...

Green waste (leaves, grass and shredded twigs) was composted for 5.5 months in a wooden composting bioreactor, of 1 m3 capacity, using both passive convective aeration, facilitated by the design of the bioreactor, and manual turning. Temperature was measured daily, while samples were analysed for...

Foaming and bulking problems in activated sludge treatment plants are associated to the presence of a variety of filamentous bacteria. However, it has been observed that M. parvicella is the most frequent filamentous microorganism causing sludge bulking and foaming, especially in treatment plants...

The methylation of mercury has been investigated and documented mainly in sediments, fish and microorganisms, while limited number of relevant studies is available for wastewater. The procedure of mercury methylation can occur via biological pathway (by microorganisms) and via chemical or...

Chlorination has been the most widely used technology for the disinfection of drinking water around the world. The main purpose for the disinfection of drinking water is to protect it against microbial contamination in the distribution systems and to prevent or at least control re-growth of...

In this study two bench scale activated sludge systems were used, a CSTR and an SBR for the treatment of coke – oven wastewater. Both reactors were inoculated with activated sludge from a municipal wastewater treatment plant. At the first stages of operation, reactors were feed by a mixture of...

Biological treatment has been carried out in two different systems: aerated closed and threephase fluidized bed reactors for hydrocarbons removal from refinery wastewaters. For the two systems, hydrodynamic study allowed the determination of operating conditions before treatment experiments. Then...

Major environmental problems in metallic mining areas come from the hazard of metal pollution of surrounding areas. Therefore, an appropriated management of these soils is necessary for minimizing the associated risks. Some properties of mining soils, such as elevated metal concentrations, pH and...

Photocatalysis by titanium dioxide (TiO2) is a water treatment method. Pseudomonas aeruginosa is a microorganism resistant to chlorine and UV-C irradiation. TiO2 photocatalytic technology can destroy bacteria, which are resistant to oxidative destruction of cell membrane caused by sole UV...