Ultrafiltration for the reuse of spent filter backwash water from drinking water treatment (original) (raw)
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The concern with water quality problems worldwide has led to the improvement of water/wastewater treatment processes. In this PhD project, industrial water and drinking water treatments using membrane processes were investigated in three different case studies. The main aim of these works was the assessment, optimisation and validation of the process’s technologies for the respective case studies. These studies included in a laboratory stage followed by a pilot-scale stage. The first case study contemplates residual water from a rubber industry presenting high chemical oxygen demand (COD). The impact of retrofitting of the existent wastewater treatment process with the replacement of the previously used evaporator with an integrate system (nanofiltration+ evaporator), was evaluated. Two modes of operation were considered, batch and continuous, depending on the daily flowrate of water to be treated in this industry. The second case study addresses surface water treatment, for product...
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Removal of various pollutants from waste water can be facilitiated by various methods. Conventional treatment methods include physical treatment followed by biological treatments , either attached growth or suspended growth. These methods have their own disadvantages like large land area requirements, disposal of the sludge produced in the treatments, operating problems under various conditions of temperature. Membrane technology is very promising and widely studied alternative. The current review aims at studying the research carried out for application of membrane technology for the wastewater treatment. During the review it was found that the membrane technologies such as electro dialysis, membrane bioreactors, anaerobic membrane bioreactors, reverse osmosis, ultrafiltration, microfiltration, nanofiltration etc. can be used effectively for wastewater treatment. High efficiency and low area requirement, compactness are key features of this technology. This technology can be combined with conventional aerobic and anaerobic treatment facilities to increase the effectiveness. Membrane technology is the most important method in achieving the objective of reuse of wastewater in an era of water scarcity in many parts of the world
Data in brief, 2017
During operation of most water treatment plants, spent filter backwash water (SFBW) is generated, which accounts about 2-10% of the total plant production. By increasing world population and water shortage in many countries, SFBW can be used as a permanent water source until the water treatment plant is working. This data article reports the practical method being used for water reuse from SFBW through different method including pre-sedimentation, coagulation and flocculation, second clarification, ultra filtration (UF) and returned settled SFBW to the beginning of water treatment plant (WTP). Also, two coagulants of polyaluminum ferric chloride (PAFCl) and ferric chloride (FeCl) were investigated with respect to their performance on treated SFBW quality. Samples were collected from Isfahan's WTP in Iran during spring and summer season. The acquired data indicated that drinkable water can be produced form SFBW by applying hybrid coagulation-UF process (especially when PAFCl used...
Membrane-Based Processes to Obtain High-Quality Water From Brewery Wastewater
Frontiers in chemical engineering, 2021
Water reuse is a safe and often the least energy-intensive method of providing water from non-conventional sources in water stressed regions. Although public perception can be a challenge, water reuse is gaining acceptance. Recent advances in membrane technology allow for reclamation of wastewater through the production of high-quality treated water, including potable reuse. This study takes an in-depth evaluation of a combination of membrane-based tertiary processes for its application in reuse of brewery wastewater, and is one of the few studies that evaluates long-term membrane performance at the pilotscale. Two different advanced tertiary treatment trains were tested with secondary wastewater from a brewery wastewater treatment plant (A) ultrafiltration (UF) and reverse osmosis (RO), and (B) ozonation, coagulation, microfiltration with ceramic membranes (MF) and RO. Three specific criteria were used for membrane comparison: 1) pilot plant optimisation to identify ideal operating conditions, 2) Clean-In-Place (CIP) procedures to restore permeability, and 3) final water quality obtained. Both UF and Micro-Filtration membranes were operated at increasing fluxes, filtration intervals and alternating phases of backwash (BW) and chemically enhanced backwash (CEB) to control fouling. Operation of polymeric UF membranes was optimized at a flux of 25-30 LMH with 15-20 min of filtration time to obtain longer production periods and avoid frequent CIP membrane cleaning procedures. Combination of ozone and coagulation with ceramic MF membranes resulted in high flux values up to 120 LMH with CEB:BW ratios of 1:4 to 1:10. Coagulation doses of 3-6 ppm were required to deal with the high concentrations of polyphenols (coagulation inhibitors) in the feed, but higher concentrations led to increasing fouling resistance of the MF membrane. Varying the ozone concentration stepwise from 0 to 25 mg/L had no noticeable effect on coagulation. The most effective cleaning strategy was found to be a combination of 2000 mg/L NaOCl followed by 5% HCl which enabled to recover permeability up to 400 LMH•bar −1. Both polymeric UF and ceramic MF membranes produced effluents that fulfil the limits of the national regulatory framework for reuse in industrial services (RD 1620/2007). Coupling to the RO units in both tertiary trains led to further water polishing and an improved treated water quality.