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Millions of dollars are being spent worldwide on the repair and maintenance of sewer systems and wastewater treatment plants. Microbially-induced corrosion causes damage via micro-organisms. Deterioration is caused by acid excretion which etches the surface of concrete, penetrating the mortar surface, especially in sewer systems. The mechanisms of concrete and reinforcement deterioration in sewer environments and microbially-induced corrosion is discussed in detail in this paper. A comprehensive review is given of the role of hydrogen sulphide and micro-organisms in the deterioration of concrete in sewer environments and of repair and rehabilitation measures, including the following preventative measures: (a) modification of the materials used in construction of sewer pipes; (b) coatings; (c) sewer treatments. A complete review of the microbial deterioration of concrete and its remedies is also included.

The coffee processing industry is one of the major agro-based industries contributing significantly in international and national growth. Coffee fruits are processed by two methods, wet and dry process. In wet processing, coffee fruits generate enormous quantities of high strength wastewater requiring systematic treatment prior to disposal. Different method approach is used to treat the wastewater. Many researchers have attempted to assess the efficiency of batch aeration as posttreatment of coffee processing wastewater from an upflow anaerobic hybrid reactor (UAHR)-continuous and intermittent aeration system. However, wet coffee processing requires a high degree of processing know-how and produces large amounts of effluents which have the potential to damage the environment. Characteristics of wastewater from coffee processing has a biological oxygen demand (BOD) of up to 20,000 mg/l and a chemical oxygen demand (COD) of up to 50,000 mg/l as well as the acidity of pH below 4. In this review paper, various methods are discussed to treat coffee processing wastewaters; the constitution of wastewater is presented and the technical solutions for wastewater treatment are discussed.

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The production of electrical and electronic equipment (EEE) is one of the fastest growing global manufacturing activities. This development has resulted in an increase of waste electric and electronic equipment (WEEE). Rapid economic growth, coupled with urbanization and growing demand for consumer goods, has increased both the consumption of EEE and the production of WEEE, which can be a source of hazardous wastes that pose a risk to the environment and to sustainable economic growth. To address potential environmental problems that could stem from improper management of WEEE, many countries and organizations have drafted national legislation to improve the reuse, recycling and other forms of material recovery from WEEE to reduce the amount and types of materials disposed in landfills. Recycling of waste electric and electronic equipment is important not only to reduce the amount of waste requiring treatment, but also to promote the recovery of valuable materials. EEE is diverse and complex with respect to the materials and components used and waste streams from the manufacturing processes. Characterization of these wastes is of paramount importance for developing a cost-effective and environmentally sound recycling system. This paper offers an overview of electrical and e-waste recycling, including a description of how it is generated and classified, strategies and technologies for recovering materials, and new scientific developments related to these activities. Finally, the e-waste recycling industry in India is also discussed.

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The performance characteristics of high-strength and high-performance concrete are discussed in this review. Recent developments in the field of high-performance concrete marked a giant step forward in high-tech construction materials with enhanced durability, high compressive strength and high modulus of elasticity particularly for industrial applications. There is a growing awareness that specifications requiring high compressive strength make sense only when there are specific strength design advantages. HPC today employs blended cements that include silica fume, fly ash and ground granulated blast-furnace slag. In typical formulations, these cementitious materials can exceed 25% of the total cement by weight. Silica fume contributes to strength and durability; and fly ash and slag cement to better finish, decreased permeability, and increased resistance to chemical attack. The influences of various mineral admixtures such as fly ash, silica fume, micro silica, slag etc. on the performance of high-strength concrete are discussed.

Textile dye wastewater is well known to contain strong colour, high pH, temperature, Chemical Oxygen Demand (COD) and biodegradable materials. The electrochemical treatment of wastewater is considered as one of the advanced oxidation processes, potentially a powerful method of pollution control, offering high removal efficiencies the removal of colour of methyl red azo dye is a challenge in textile industry. The following methods have been adopted for the treatment of real textile wastewater: 1) Electro-oxidation (EO) and 2) Bio-treatment (BT). In EO process, reduction of COD and removal of colour were 70% and 81% respectively. The effluent was further treated by BT. BT showed a final reduction of 92% of COD and removal of colour by 95%. Both the combined processes were highly competitive and showed a very good reduction of COD and colour removal. Electrochemical processes generally have lower temperature requirement than those of other equivalent non-electrochemical treatments and there is no need for additional chemicals. These treatment methods may also be employed successfully to treat other industrial effluents