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Shaw W.A.,Veolia Water Solutions and Technologies

Wastewater from wet flue gas desulfurization (wet FGD) systems and integrated gasification combined cycle (IGCC) plants contains highly soluble salts, e.g., calcium and ammonium chlorides, and certain heavy metal salts, which are not so easy to crystallize by evaporation. Discharge of FGD and IGCC wastewaters is usually regulated due to the presence of relatively small amounts of toxic contaminants, such as heavy metals, selenium, boron, and organics. A discussion covers the conventional treatment methods; water evaporation process; crystallization that occurs in the forced-circulation evaporator-crystallizer; alternatives for the use of a crystallizer; and HPD's new ZLD process employing the approach used in industrial crystallization of very soluble chloride salts; a unique low-temperature crystallization process known as the CoLD Process (Crystallization of high-solubility salts at low temperature and deep vacuum). Source

Li J.,Virginia Polytechnic Institute and State University | Rosenberger G.,Veolia Water Solutions and Technologies | He Z.,Virginia Polytechnic Institute and State University
Chemical Engineering Journal

Membrane bioelectrochemical reactors (MBERs) integrate membrane filtration module into microbial fuel cells (MFCs) to achieve silmultaneous wastewater treatment, bioenergy production, and high-quality effluent. Previous MBERs usually have membrane modules as a part of the MFC reactors that creates challenges for membrane cleaning. In this study, an MBER with an external membrane module was investigated through both experiments and mathematical modeling. This MBER produced a current density of 7.1±0.5Am-3 with an anolyte recirculation of 90mLmin-1; reducing the anolyte recirculation rate had a negligible effect on MBER's electrical performance but resulted in a positive energy balance of 0.003±0.002kWhm-3. Periodic backwashing (1min-backwashing/15min-operation) was demonstrated as an effective method for fouling control. A mathematical model was developed and validated using the experimental data. The model could predict the influence of key parameters such as influent organic concentration and anolyte flow rate on the current generation, and identify the maximum organic loading rate for current generation. Those results encourage further investigation and development of this MBER toward system scaling up. © 2015 Elsevier B.V.. Source

Salgado B.,Dow Chemical Company | Majamaa K.,Dow Chemical Company | Sanz J.,Veolia Water Solutions and Technologies | Molist J.,Agencia Catalana de lAigua
Desalination and Water Treatment

Within the current and future world's water scarcity, the reuse of treated waste water for specific applications offers an appealing alternative to conventional fresh water sources that cannot meet the expectations, mostly in terms of quantity. Spain is no exception to this global situation, with a constantly increasing population, in combination with growing water demand for applications such as production industry, exportation oriented agriculture, tourism development, and booming construction, access to sufficient quantities of fresh water is currently a rising concern. Camp de Tarragona (ACA) Water Reclamation Project is a prime example how water scarcity can be solved regionally by reclaiming water that would otherwise be discharged to the sea. The new reclamation plant treats municipal secondary effluent from Tarragona and Salou/Vilaseca Wastewater Treatment Plants to supply process water for the petrochemical industry of Tarragona. The plant capacity is currently 19,000 m3/d (Phase I), and further expansions are planned for increases up to 29,000 m3/d (Phase II) and even to 55,000 m3/d (Phase III) in the coming years. This additional supply would replace the water currently taken from the Ebro River, thus releasing this volume for drinking water supply to the population. Utilizing such a process, the industrial growth in water scarce regions can be supported and industry sustainability is increased further. A pipeline connects the two different Wastewater Treatment Plants (WWTPs), 10 km apart from each other, and feeds secondary treated effluent to the reverse osmosis (RO) pretreatment process. The pretreatment consists of ballasted flocculation, followed by disc filtration, sand filtration, and multimedia filtration prior feeding it to the two pass RO system. Final permeate treatment is done by UV light and chlorine disinfection, prior releasing water to the distribution system. This paper will review the detailed design of the plant, as a scale-up of pilot plant results, as well as the RO membranes performance data obtained during the start-up of the installation. RO performance is evaluated in detail taking into account the performance differences when different combinations of raw water sources were used. This paper will also explain in detail the preservation of the installation by means of 5-Chloro-2-Methyl-2H-Isothiazol-3-one/2-Methyl-2HIsothiazol-3-one (CMIT/MIT), during a medium term stop of the plant. © 2013 Desalination Publications. Source

Bourke C.,Veolia Water Solutions and Technologies Australia Pty Ltd | Mack B.,Veolia Water Solutions and Technologies
AusIMM Bulletin

The cost of water treatment is now more than ever a major consideration for maintaining an environmentally and economically sustainable mining operation. As an industry, we often have to consider water sources that are highly impure and difficult to treat. We are also discovering the value of our waste waters in this regard and using new and improved methods and technology to reclaim and reuse water. In many instances, the water or waste water to be treated is highly acidic and saturated in sparingly soluble salts. Conventional systems used to liberate this type of water typically involve high doses of lime with large volumes of waste sludge produced, and are comparatively complex to operate, to pretreat the water in order to reduce scaling tendency on the reverse osmosis stage. However, if the water is considered valuable for reuse, then why not avoid difficult and cumbersome pretreatment processes and treat the water at low pH to keep the sparingly soluble salts, metals and other dissolved species in solution. This paper describes a patented technology that uses and successfully proves this concept as a cost effective option for certain situations. Results from a treatability study on an Australian groundwater are discussed, along with an economic comparison to a conventional method and discussion on full-scale potential. Source

Lee J.J.,University of Technology, Sydney | Johir M.A.H.,University of Technology, Sydney | Chinu K.H.,University of Technology, Sydney | Shon H.K.,University of Technology, Sydney | And 4 more authors.

A high rate fibre filter was used as a pre-treatment to seawater reverse osmosis (SWRO) to reduce membrane fouling. Seawater was drawn from Chowder Bay where the Sydney Institute of Marine Science, Australia is located. A lab-scale fibre filter with a height of 1000 mm and a diameter of 30 mm was used in conjunction with in-line coagulation. The effect of operating the fibre filter with different packing densities (105, 115 kg/m3) and filtration velocities (40, 60 m/h) was investigated in terms of silt density index (SDI10), modified fouling index (MFI), pressure drop (ΔP), turbidity and molecular weight distribution (MWD). The use of in-line coagulation improved the performance of fibre filter as measured by the MFI and SDI. Regardless of filtration velocity and packing density the MFI and SDI10 values remained low as did the turbidity until the end of the filtration run. The MWD analysis showed the removal efficiencies of organic materials like biopolymers, fulvic acids, low MW acids for even experiments with the highest filtration velocity (60 m/h) and lowest packing density (105 kg/m3). This pre-treatment has a small foot print as it has the capacity of operating at a very high filtration velocity. © 2009 Elsevier B.V. All rights reserved. Source

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