Flavour assessment of blends between desalinated and conventionally treated sources

Energy management and DSM techniques for a PV-diesel powered sea water reverse osmosis desalination plant in Ginostra, Sicily

Integrating membrane technologies and blending options in water production and distribution systems to improve organoleptic properties. The case of the Barcelona Metropolitan Area

Evaluation and characterization of seawater RO membrane fouling

This article shows a climate change mitigation strategy by means of membranes replacement and determination methodology of carbon footprint in reverse osmosis (RO) desalination plants, valid for all the islands, and even isolated territories in the continent. This study takes the case of study of Canary Islands, where there are more than 320 desalination plants with different sizes, private, and public. The objective is to propose a new method which integrates this analysis with the replacement of membranes, from 0% to 20% per year in sea water reverse osmosis desalination plants, to reduce the carbon footprint and ecological footprint. If it is considered a replacement of 20% of the elements per year, the carbon footprint could be reduced to between 5% and 6% and even more if it is introduced low energy consumption membranes instead of high rejection elements. The factor mix in Canary Islands, according to the technological structure of the generation park that uses oil products, is around 0.678 kgCO2/kWh, much higher than in the Spanish mainland where it is 0.263 kgCO2/kWh. Therefore, it is estimated in Canary Islands 5,326,963 t CO2/year can be emitted, which represents 2.4 tCO2/person/year, 12 times more the admissible admissions per inhabitant in the Canary Islands, only considering the seawater desalination sector. This document shows the different results of the analysis of energy efficiency and the environmental footprints. This study may serve as a tool for the decision-making processes related to how to improve energy efficiency in desalination plants.

Case study: Integrating membrane processes with evaporation to achieve economical zero liquid discharge at the Doswell Combined Cycle Facility

Brackish water desalination is an important alternative for developing drinking water sources in arid regions. Electrodialysis reversal (EDR) and reverse osmosis (RO) are suitable technologies for desalination of brackish groundwater. Pilot testing conducted with brackish groundwater containing 1,200 mg/L of total dissolved solids (TDS) and 60 mg/L of silica demonstrated that RO can operate at 10 gfd with 75 percent recovery and 96 percent TDS rejection. As predicted by modeling software for the same water chemistry, the EDR process can operate at 88 percent recovery with TDS rejection of 78 percent. Order of magnitude cost estimates (−30 percent and +50 percent) prepared for three feed-flow scenarios (3, 5, and 8 mgd) for RO and EDR treating the same groundwater suggested both processes are comparable, especially when feedwater contains elevated silica levels.

Artificial neural networks applied to manage the variable operation of a simple seawater reverse osmosis plant

Energy and environmental issues of seawater reverse osmosis desalination considering boron rejection: A comprehensive review and a case study of exergy analysis

Institute of African research and studies, Cairo University

80,000 h operational experience and performance analysis of a brackish water reverse osmosis desalination plant. Assessment of membrane replacement cost

It is well established that to sustain the growth in human population commensurate growth in potable water resources is a necessity. Thus, to produce “extra” water in potable form, technologies like sea-water or brackish water desalination is resorted which include thermally driven technologies like multi-stage flash (MSF) or multi effect distillation (MED) or pressure driven like reverse osmosis (RO). It is well established that operation of “State of Art” RO plants are energetically closest (3–6 kWh/m3) to thermodynamic limits (1.56 kWh/m3 for 50% recovery of 35,000 ppm feed) of desalination whereas MSF or MED are more energy intensive (20 kWh/m3 and higher). Hence, RO has gained widespread popularity over the last few decades. However, as fresh water is extracted from seawater, what remains is concentrated brine, which has almost twice the salt concentration of sea-water and is(increasingly becoming) an environmental concern. Therefore, Zero Liquid Discharge (ZLD) desalination processes for brine or hypersaline streams management from land locked desalination is an absolute necessity. As RO itself is a mature technology, there is little scope in improvement of the same as far as membrane configuration and chemistry is concerned. Hence, in this book chapter, the authors discuss sustainability of desalination from two perspectives. One is to explore the potential to integrate solar/wind energies to desalinate water through RO. This would lead future efforts into solar and wind related developments as well as energy storage devices influencing RO. Then the chapter delves into handling the RO reject. The reject brine of RO (or any hypersaline stream) can be subjected to three approaches: (i) Water for Energy (WFE), (ii) Energy for Water (EFW) and (iii) Brine to Chemicals (BTC). The selection of WFE and EFW depends on the degree of salinity (DOS). If the DOS is large, indicating high osmotic pressures, then it is advisable to recover the osmotic energy of the stream to generate power (WFE) through technologies like Pressure Retarded Osmosis or Reverse Electrodialysis. However, EFW approach can also be undertaken utilizing brine concentrator (BC) to generate water and recover salts from brine. Zero Liquid Discharge approach utilizing BC and aided by membrane-based forward osmosis (FO)/electrodialysis reversal (EDR)/membrane distillation (MD) to achieve 10% concentration of brine followed by BC (to attain 22% concentration) is also discussed. To achieve ZLD, Forced Circulation Crystallizer (FCC) is utilized downstream of BC. This process will recover salts as valuable byproduct and thereby improve the overall techno-economics. Challenges involved in design and development of ZLD desalination processes for wider scale application of these technologies in desalination and other industries is discussed. A new avenue worth exploring is BTC, which involves integration of Chlor-Alkali processes to recover Chlorine and Hydrogen from brine which are extremely important to the chemical industry to produce water treatment chemicals (using Chlorine) as well as for producing urea (using hydrogen through Haber process) for agriculture. Thus, the book chapter focuses not only on making RO sustainable but also provides futuristic avenues to make the Water-Energy and Water-Energy-Food Nexus more sustainable.KeywordsDesalinationReverse osmosisWater-energy nexusBrine handlingSustainability

Decentralized brackish water reverse osmosis desalination plant based on PV and pumped storage - Technical analysis

Long-term performance decline in a brackish water reverse osmosis desalination plant. Predictive model for the water permeability coefficient

The metropolitan area of Barcelona suffers from a well known lack of water resources. To mitigate this situation the El Prat Desalination Plant, a seawater reverse osmosis (RO) facility, is scheduled to come into operation during 2009. The network management project foresees supply in the southern area of the city of a blend of desalinated seawater and water from the River Llobregat. The latter could be treated in two ways: by conventional treatment consisting of the predioxychlorination, clarification, sand filtration, GAC filtration and postchlorination stages, or by means of this same process with an additional electrodialysis reversal (EDR) stage prior to postchlorination. In this study, an estimation of the organoleptic characteristics of the blends was carried out by trained and untrained sensory panels. The water samples for tasting were RO desalinated seawater (Tordera Plant), treated water from the Llobregat (Sant Joan Despí water treatment plant working under adequate conditions for the study), and the effluent from an EDR pilot plant. The results of the ranking, scoring and triangle difference tests indicated that the quality of the 50/50 blends improved in relation to the water from the Llobregat, although without reaching the level of quality of the water from the Ter basin, Barcelona's other important resource (North area).

Intensification and energy minimization of seawater reverse osmosis desalination through high-pH operation: Temperature dependency and second pass implications