Heavy Metal Removal Investigation in Conventional Activated Sludge Systems

Abstract

The combination of industrial and domestic wastewater in municipal WWTPs (waste water treatment plants) may be economically profitable, but it increases the difficulty of treatment, and also has some detrimental effects on the biomass and causes a low-quality final effluent. The present study evaluates the treatment process both in the presence and absence of heavy metals using ASM3 (activated sludge model no.3) so as to improve the model by means of incorporating other novel inhibitory kinetic and settler models. The results reveal that the presence of heavy metal, a case study for copper and cadmium at a concentration of 0.7 mgL−1 in a biological treatment system has a negative effect on heterotrophic bacteria concentration by 25.00 %, and 8.76 % respectively. Meanwhile, there are no important changes in COD (chemical oxygen demand), SS (total suspended solids) and TN (total nitrogen) in the final effluent in the conventional system. However, all these parameters are acceptable and consistent with EU Commission Directives. The results indicate that ASM3 can predict and provide an opportunity of the operation for an activated sludge wastewater treatment plant that receives the effluent from an industrial plant.

Spatial Distribution and Source Apportionment of Soil Heavy Metals in Pearl River Delta, China

“…where, Y is the total concentration of the pollutants, P is the number of factors extracted by the PCA, a h is the standardized regression coefficient of the h factor, X h is the score of the h factor extracted by PCA, and b is the regression constant term. The independent and dependent variables were standardized and regression analysis was performed by the standardized Equation (5).…”

“…Agricultural and industrial activities have intensified the input of HMs to soil ecosystems [4]. HMs, such as Cu, Zn, Ni, Cd, Pb, Cr, Hg, and As, not only affect the quality of crops, but also accumulate in the human body through food-chain accumulation and harm public health, resulting in most countries listing them as priority pollutants to control [5][6][7]. The abovementioned eight HMs have been listed as priority pollutants by the United Environmental Protection agency, based on a series of hazards.…”

Copper Removal Mediated by Pseudomonas veronii 2E in Batch and Continuous Reactors

“…Also, excessive Cu(II) intake leads to severe mucosal irritation and corrosion, stomach upset or ulcer, wide spread capillary, hepatic and renal damages (for example Wilson's disease leading to brain damage), central nervous system irritation followed by depression, gastrointestinal irritation and possible necrotic changes in the liver and kidney [18,19]. Besides, there are reported studies of copper toxicity in microorganisms [20].…”

Hydrolytic performances of different organic compounds in different lignocellulosic biomass during anaerobic digestion

“…Lignocellulose comprised the main part of organic compounds in LBs, whose proportion were about 66-78% in crop straws [10], 75-94% in different grass [11], 64-75% in different leaves [12] and 14-44% in excess sludge (ES) [12,13]. The lignocellulosic contents in these LBs are different, and their composition and structure also vary a lot.…”