The biological treatment of wastewater discharged from a biodiesel fuel (BDF) production plant conducting alkali catalysis transesterification was investigated. BDF wastewater has a high pH and high hexane-extracted oil and low nitrogen concentrations, and inhibits the growth of microorganisms. The biological treatment of BDF wastewater is difficult because the composition of such wastewater is...

Abbreviations: BOD: biochemical oxygen demand COD: chemical oxygen demand OD: optical density OW: optimized wastewater PNSB: purple non sulphur photosynthetic bacteria ROW:raw optimized wastewater RW: raw wastewater SCP: single cell protein SEM: scanning electron microscope SOW: sterile optimized wastewater SW: sterile wastewater TEM: transmission electron microscope TKN: total kjeldahl nitroge...

Due to increasing scarcity of fresh water, use of unconventional water source (e.g., wastewater) in irrigation has now become important. However, inclusive information on the effects of wastewater on crop production and soil health is necessary for such intervention. This study was designed to evaluate these effects by demonstrating the contribution of municipal wastewater (hereafter called was...

The aim of this research was to determine the characteristics, volumes and treatability of Full-service carwash wastewaters in Toluca (Mexico State). The average water use for Exterior-only wash was 50 L per small-size car and 170 L per medium-size vehicle (pick up, van or light truck). The Full-service wash (exterior, engine and chassis) required 170 L per small-size car and 300 L per light tr...

Many wastewater managers in developing countries struggle with the daily operation of urban wastewater systems. Technically well-designed wastewater collection and treatments are often degraded and/or not properly functioning. In this paper, a realistic rehabilitation strategy is developed for the urban wastewater system of Coronel Oviedo (Paraguay), in which the actual performance is unsatisfa...

Biocatalysis based effluent treatment has outclassed the presently favored physico-chemical treatments due to nil sludge production and monetary savings. Azo dyes are commonly employed in the leather industry and pose a great threat to the environment. Here, we show the degradation of C. I. Acid blue 113 using horseradish peroxidase (HRP) assisted with H2O2 as a co-substrate. It was observed th...

Soil-transmitted helminths (STHs) pose a significant public health problem, infecting approximately 2 billion people globally. Despite relatively low prevalence in developed countries, the removal of STHs from wastewater remains crucial to allow the safe use of biosolids or recycled water for agriculture. Wastewater helminth egg count data can contribute to an assessment of the need for, or suc...

Previous studies modeled NDMA formation during chlorine disinfection as arising from the oxidation of an unsymmetrical dimethylhydrazine intermediate formed from the reaction of monochloramine and dimethylamine. However, chlorination of wastewater effluents indicated that this mechanism could not account for a significant portion of the observed NDMA formation. Laboratory studies indicated that...

The aim of this study was to investigate the performance of horizontal subsurface flow constructed wetlands planted with Typha latifolia treating tannery wastewater under long-term operation. Two expanded clay aggregates (Filtralite MR3-8-FMR and Filtralite NR3-8-FNR) and a fine gravel-FG were used as substrate for the constructed wetland units plus one unit with FMR was left as an unvegetated ...

A 100-L microbial electrolysis cell (MEC) was operated for a 12-month period fed on raw domestic wastewater at temperatures ranging from 1°C to 22°C, producing an average of 0.6 L/day of hydrogen. Gas production was continuous though decreased with time. An average 48.7% of the electrical energy input was recovered, with a Coulombic efficiency of 41.2%. COD removal was inconsistent and below th...