Removal of Multi-Metals from Water Using Reusable Pectin-Cellulose Microfibers Composite Beads

Water is one of the world’s most abundant resources, but less than 1% of the global supply of water is available and safe for human consumption [1]. According to the World Health Organization, over 760 million people were without adequate drinking water supply in 2011 [2]. Where it is available, the cost of potable water is rising due to increasing energy costs, growing populations, and climatic or other environmental issues [1,3]. In addition, an increasing number of drinking water sources are showing evidence of contamination, especially by emerging pollutants like pharmaceuticals and personal care products [4,5]. Many traditional water and wastewater treatment methods do not effectively remove these emerging contaminants, and/or are not capable of removing enough to meet increasingly stringent water quality standards [5,6]. Contamination of surface waters also constitutes a risk to water supplies because pollutants may penetrate into aquifers, where they can be transported to drinking water sources.

ABSTRACT The objective of this study was to evaluate the efficiency of electrocoagulation in the removal of Escherichia coli from domestic and urban wastewaters and to determine the effects of the main operational parameters on the process. An electrocoagulation reactor with aluminum and iron electrodes was built for this purpose. A factorial design was applied, where amperage, treatment time, and pH were considered as the factors and E. coli percent removal was the response variable. After 20 min of treatment, >97% removal efficiency was achieved. The highest E. coli removal efficiency achieved was 99.9% at a neutral pH of 7, amperage of 3 A, and treatment time of 60 min. However, the removal efficiency of close to 99% was also achieved at natural wastewater pH of 8.5. The statistical analyses showed that the three tested factors significantly affected the E. coli removal percentage (p < 0.05). These results indicate that electrocoagulation has a high disinfection power in a primary reactor in removing water con[1]taminants as well as simultaneously removing pathogenic microorganisms when compared to biological treatment processes. This represents an additional benefit, because it will considerably reduce the use of chlorine during the final disinfection stage.

Biofouling is a critical issue in membrane water and wastewater treatment as it greatly compromises the efficiency of the treatment processes. It is difficult to control, and significant economic resources have been dedicated to the development of effective biofouling monitoring and control strategies. This paper highlights the underlying causes of membrane biofouling and provides a review on recent developments of potential monitoring and control methods in water and wastewater treatment with the aim of identifying the remaining issues and challenges in this area.

Abstract In this study, the performance of different adsorbents—red clay, zeolite, limestone, and oyster shell—for adsorption of polymetallic ions (Cr3+, Ni2+, Cu2+, Zn2+, As3+, Cd2+, and Pb2+) were investigated from aqueous solutions.

Abstract: The use of water disinfection as a public health measure reduces the spread of diseases. Various disinfection technologies can be used to meet the pathogen inactivation demand in water. This work is an overview of the main disinfection technologies of wastewater and drinking water that reports for the conventional processes the action mechanism, the possible formation of by-products, the operative conditions, the advantages and disadvantages. For advanced and natural processes the action mechanisms are reported. Advanced technologies are interesting but are still in the research state, while conventional technologies are the most used. There is a tendency, especially in Italy, to use chlorine-based disinfectant, despite in some forms could lead to production of disinfection by-products.

Abstract Developing country causes growth of industries sectors. Despite that industrial sectors releases massive amount of waste water into the environment. At the same time, the increasing number of vehicles in Malaysia promotes the development of automobile workshop that produces huge amount of wastewater as well. Wastewater contains high level of suspended total solids and leave untreated. For instance oil, grease, dyestuff, chromium, phosphate in washing products and colouring, as well as heavy metals such as lead, cadmium, barium and others potential metals. All these hazardous wastes directly pollute the environment especially the groundwater and harm the ecosystem. In order to minimize and reduce the impact to the environment, the wastewater needed to be treated using technology such as permeable reactive barrier (PRB). Activated carbon is one of the PRB utilised. It is a compromised material for treatment of wastewater where there are varieties of sources to produce activated carbon. Malaysia as an active agricultural country, massive amount of agriculture wastes can be turned into activated carbon. They are two methods used to produce activated carbon, namely furnace heat processing and microwave processing. The usage of furnace and microwave instruments can produce different quality of activated carbon due to different mechanism involves. Furnace heat processing transferred the heat from external to the internal but microwave processing is vice versa. In this article, a brief overview of activated carbon usage for wastewater treatment is highlighted.