Treatment Of High Strength Distillery Wastewater (Cherry Stillage) By Integrated Aerobic Biological Oxidation And Ozonation

Introduction In the future, the world is confronted with energy and freshwater shortage. Desalination of brackish or seawater is one of the most important ways to solve the water scarcity issue [1, 2]. The use of solar energy or waste heat sources is acceptable for water-producing systems of such a small size [3–5]. The relevancy of nanomaterials is to realize the best attainable properties within the smallest possible loadings through homogenized distribution and stable suspension of these nanoparticles[6–11]. Often, heat transfer improvement in solar collectors is one of the basic problems in energy saving, compact designs, and different operating temperatures. Researchers also investigated the multiwalled carbon nanotubes (MWCNTs) and water nanofluids with a pH of 3.5, 6.5, and 9.5, and Triton X-100 as a surfactant (0.2 wt %) using flat-plate solar collectors. It was found that the nanofluids have better heat transfer performance in acidic and alkaline water due to the influence of the isoelectric point. The higher efficiency (67 %) was obtained at pH 9.5 and 3.5 with a water flow rate of 0.0333 kg s–1. A stable nanofluid based on ethylene glycol-containing nanosheets of graphene oxide was prepared by Yu et al. [12]. The improvement in thermal conductivity relies strongly on the volume fraction of the nanosheet of graphene oxide and increases with higher nanoparticle loading. The heat efficiency was enhanced up to 61.0 % using a nanosheet loading of 5.0 vol %. For seven days, the thermal conductivity of the fluids remained almost constant, which suggests their high stability. In the measured temperature range, the enhancement value was independent of the temperature. Peyghambarzadeh et al. [13, 14] studied force convection techniques in an excessively base water nanofluid, which was experimentally compared to water in a vehicle heat exchanger with different nanofluid loadings. It was experimentally investigated to improve the rate of heat transfer. The variable effect of the inlet temperature of the fluid in the heat exchanger on the heat transfer coefficient was evaluated. The findings showed that the incremental fluid circulation rate would increase the output rate of heat transfer, while the temperature of the fluid entering the heat exchanger had negligible effects. Meanwhile, water nanofluid subservience at low-volume loadings would increase the heat transfer rate efficiency by approximately 44 % compared to water

Abstract: Dynamic membrane system behaviour must be adequately addressed to avoid process unfeasibility. The lack of proper analysis will mean relying on erroneous permeate flux values in the system design, which will lead to quick and/or steady high fouling rates. In this paper, the authors present additional data supporting the boundary flux theory as a helpful tool for membrane engineers to carefully avoid process failures. By fitting the dynamic permeate flux data to the boundary flux model, it was possible to calculate the β fouling index for the three selected membranes (one nanofiltration (NF) and two reverse osmosis (RO) ones). The dynamic flux given by the low-pressure RO membrane did not follow sub-boundary operating conditions, since a sharp flux loss was measured throughout the whole operating cycle, pinpointing that supra-boundary flux conditions were governing the system. This was supported by the calculated value of the β fouling parameter, which resulted to be in the order of ten times higher for this membrane. However, the values of β→0 for the SC-RO and DK-NF ones, supported by the very low value of the sub-boundary fouling parameter α (0.002 and 0.007 L·h −1·m−2 ·bar−2 , respectively), ensure nearly boundary operating conditions for these membranes.

Abstract: Due to advances in desalination technology, desalination has been considered as a practical method to meet the increasing global fresh water demand. This paper explores the status of the desalination industry and research work in South Korea. Desalination plant designs, statistics, and the roadmap for desalination research were analyzed. To reduce energy consumption in desalination, seawater reverse osmosis (SWRO) has been intensively investigated. Recently, alternative desalination technologies, including forward osmosis, pressure-retarded osmosis, membrane distillation, capacitive deionization, renewable-energy-powered desalination, and desalination batteries have also been actively studied. Related major consortium-based desalination research projects and their pilot plants suggest insights into lowering the energy consumption of desalination and mitigation of the environmental impact of SWRO brine as well. Finally, considerations concerning further development are suggested based on the current status of desalination technology in South Korea.

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.

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.