Nanofiltration and Low Energy Reverse Osmosis for Advanced Wastewaters Treatment

Over the last few decades adsorption has gained paramount importance in industry and environmental protection. Adsorption processes are widely applied for separation and purification because of the high reliability, energy efficiency, design flexibility, technological maturity and the ability to regenerate the exhausted adsorbent. One method of important extending the adsorption treatment processes is biofiltration. The biological filter relies on the activities of the community of micro-organisms that become attached onto the filter media. Microbes oxidize organic matters in water to produce energy and therefore available nutrients sources in feed water are essential for their development. Biofiltration can effectively remove organic matter that is not able to be removed from water and biologically treated sewage effluent in conventional sewage treatment. The microbial attachment process, the factors that influence biological filtration, the kinetics of microbial growth and details of the microbial community in the biofilter are discussed in detail. There are several types of biofilters including submerged filters, trickling filter, bed filter, fluidised bed. The different biofilters are described and a comparison between them is provided. The application of biofilters for treating various types of wastewater effluent is detailed.

The fashion industry contributes 20% of industrial water pollution  With a high water footprint, massive chemical use and atmospheric, water and greenhouse gas (GHG) emissions, dyehouse operations are the most environmentally damaging component of the apparel supply chain2.Global brands are responding by requiring manufacturers to treat wastewater and reduce effluent. Paradoxically, conventional water treatment systems generate toxic sludge, trading water pollution for solid, chemical discharge that is landfilled and emits GHG – mostly methane.

In many semiarid and arid countries, water is now becoming an increasingly limited resource and managers are forced to take into account sources of water that may be used economically and efficiently to encourage further development. Simultaneously, with the population increasing at a high rate, the requirement for increased production of food is apparent. The prospective for irrigation to increase both the agricultural productivity and living standards of the poor has long been acknowledged. Irrigated agriculture occupies nearly 17% of the total arable land in the world but the yield from this land includes about 34% of the world total. This perspective is even more distinct in arid areas like the Near East Region, where only 30% of the cultivated land is irrigated but it yields around 75% of total agricultural production. In the same area, more than 50% of the food necessities are imported and the increased rate in demand for the food surpasses the rate of an upsurge in agricultural production (Tunney et al., 2000).

The control of environmental pollution and also the treatment of polluted water are of great concern. Within the past decade, electrochemical coagulation process has emerged as most effective wastewater treatment process as compared to conventional techniques of treating wastewater. Electrocoagulation is robust, cost effective, reliable, low sludge generating process, it has automation amenability and it has high pollutant removal efficiency. The aim of the review is to explain the basics and up to date advancement of electrocoagulation method for the improvements in the pollutant removal efficiency.

The Swedish Environmental Protection Agency (EPA) has determined a need to introduce advanced treatment for pharmaceutical residues in wastewater. An additional benefit of such a treatment is that it would also include the treatment of other hazardous substances.The extent to which pharmaceutical residues risk becoming a problem depends on local conditions such as the sensitivity of the receiving waters. While this is an important variable to consider, the Swedish EPA believes that the sensitivity of the receiving waters should not be the only consideration when setting requirements for treatment. The amount of released pharmaceutical residues and long-term effects should also be considered in decision making and justification. The investment and operational costs of introducing advanced treatment depend in part on the size and current capacity of treatment facilities, which is why size limitations can be an additional consideration when setting requirements.