activated sludge or extended aeration treatment involves a continous system where aerobic biological growths are mixed with waste water and then separated in a gravity clarifier. therefore, waste treatment system such as the activated sludge system depend on the activities of communities of living organism. in this study, an attempt was made on the indentification of the bacterial population in...

Ethanol fermentation requires oxygen to maintain high biomass and cell viability, especially under very-high-gravity (VHG) condition. In this work, fermentation redox potential (ORP) was applied to drive the aeration process at low dissolved oxygen (DO) levels, which is infeasible to be regulated by a DO sensor. The performance and characteristics of flocculating yeast grown under 300 and 260 g...

Manganese is a redox-sensitive element in soils and sediments that plays an important role the retention of trace elements. Under anoxic conditions, clay minerals were shown to increase Cd by favoring precipitation Mn(II) phases. In this study, we investigated influence aeration on anoxically formed Mn solid phases its impact presence two with low Fe contents, natural kaolinite (KGa-1b) synthet...

The aims of these experiments were treating tapioca processing waste water to produce polyhydroxyalkanoates (PHAs) and removal of chemical oxygen demand (COD). The experiments were conducted in a sequencing batch reactor with a volume of 6 L. The entire experimental condition was anaerobic-aerobic-anaerobic. Experiment 1, 2 and 3 had the first 2 h for feeding time while Experiment 4 had 3 h. Th...

Due to urbanization and industrialization huge amount of wastewater is being generated, which causing water pollution. Nowadays pollution a serious problem. The present study has been carried out evaluate the efficiency waste treatment plants with Extended Aeration Sludge Process (EASP). This done by examining various physiochemical characteristics (BOD, COD, TSS & PO4), including compariso...

(a) The treatment efficiency in MBR was observed under different aeration rates. It was found that the optimal rate of aeration for removal efficiency was 3m/h.Increasing aeration rate resulted in shear stress, which caused elevated rates of sludge floc breakage, and consequently, supernatant COD. Excessive aeration rate could consequently also affected nitrogen removal by destructing anoxic co...

Biowaste composting at several plants in Scandinavia has been troubled by low pH in the collected waste as well as after the composting process. Our hypothesis was that increased aeration would give a higher and faster rise in pH during the composting process, and that this would give a higher decomposition rate. The objective was to test this hypothesis by experiments in full scale, with an em...

The aim of this work was to study the production of the bioinsecticide using the aerobic cultivation. Two-stage cultivation process was used: aerobic vegetative growth and end-phase of sporulation (with aeration and without aeration). The cuts of working volume evaluated were 20, 40, 60 and 80 %. The highest value of spore concentration (2.17x10 CFU/mL) and spore productivity (7.2x10 CFU/mL.h) ...

This study investigated the effects of 4 aeration levels (varied by injection of air to the soil through subsurface irrigation lines) at two subsurface irrigation line depths (15 and 40 cm) on plant growth, yield and nutritional quality of greenhouse tomato. In all experiments, fruit number, width and length, yield, vitamin C, lycopene and sugar/acid ratio of tomato markedly increased in respon...