Biocides for Disinfection and Storage of Hydranautics Membrane Elements
This bulletin provides general information about biocides that may be used with Hydranautics membrane elements for disinfection and/or storage. Before storage or disinfection of Hydranautics elements, one should become familiar with Technical Service Bulletins 108 and 118 which describe the general storage and flushing procedures for all Composite Polyamide, and PVD membrane elements. Also, one should confirm which type of membrane elements are actually in the system. Since elements may be composed of either composite polyamide membrane or polyvinyl derivative, it is imperative to be certain of the type to be disinfected.
Biocides for Disinfection and Storage of Hydranautics Membrane Elements
This bulletin provides general information about biocides that may be used with Hydranautics membrane elements for disinfection and/or storage. Before storage or disinfection of Hydranautics elements, one should become familiar with Technical Service Bulletins 108 and 118 which describe the general storage and flushing procedures for all Composite Polyamide, and PVD membrane elements. Also, one should confirm which type of membrane elements are actually in the system. Since elements may be composed of either composite polyamide membrane or polyvinyl derivative, it is imperative to be certain of the type to be disinfected.
Tailoring Advanced Desalination Technologies for 21st Century Agriculture
Abstract: Substantial parts of the U.S., particularly drier landlocked regions, are facing acute water shortages and water quality issues that decrease agricultural productivity. Reduced crop yields cause billions of dollars in losses annually, affecting the livelihoods of thousands. A combination of population growth, inefficient agricultural practices, and resource demanding consumption trends is only expected to increase pressure on our water supplies. This research proposal seeks to address water and food security issues by cost-effectively and energy-efficiently enhancing water quality and water supply in greenhouses; a $22.93 billion dollar industry in 2017 that is rapidly growing at an annual rate of 8.92%. Greenhouses widely practice desalination of salty irrigation water to improve their operations. However, currently used desalination methods do not tailor greenhouse waters based on crop requirements. This work investigates a fully integrated desalination solution that treats and tailors brackish source waters ingreenhouses to save fertilizer and water. Specifically, this project experimentally studies multi-ion transport in and assesses the economic viable of monovalent selective electrodialysis (MSED). MSED allows for the selective removal of monovalent ions damaging to crops and the retention of divalent ions beneficial for crops, unlike the widely used reverse osmosis (RO), which removes all ions from greenhouse source water. First, we evaluate the techno-economic feasibility of MSED compared to other brackish desalination technologies for agricultural applications, based on primary market research we conduct with over 70 greenhouses.
These include conventional technologies, such as reverse osmosis (RO) and electrodialysis (ED), and advanced technologies, such as closed circuit reverse osmosis (CCRO). The analysis determines the levelized costs of water, the capital costs and energy requirements of these technologies, and how these vary with feed salinity, system capacity and recovery ratio. Then, we build a bench-scale setup to experientially characterize MSED membrane properties, including monovalent selectivity, ion transport, limiting current and resistance, for multiple brackish feedwaters and for two sets of MSED membranes: the widely used Neosepta ACS/CMS membranes and the new Fujifilm Type 16 membranes. Both MSED membranes show notable monovalent selectivity for all tested compositions, reflecting the potential of the technology for selective desalination in greenhouses. The measurements are compared to a model for MSED in multi-ion solutions. The model predicts multi-ion transport for the Neosepta and Fujifilm MSED systems within 6% and 8%, respectively.
Tailoring Advanced Desalination Technologies for 21st Century Agriculture
Abstract: Substantial parts of the U.S., particularly drier landlocked regions, are facing acute water shortages and water quality issues that decrease agricultural productivity. Reduced crop yields cause billions of dollars in losses annually, affecting the livelihoods of thousands. A combination of population growth, inefficient agricultural practices, and resource demanding consumption trends is only expected to increase pressure on our water supplies. This research proposal seeks to address water and food security issues by cost-effectively and energy-efficiently enhancing water quality and water supply in greenhouses; a $22.93 billion dollar industry in 2017 that is rapidly growing at an annual rate of 8.92%. Greenhouses widely practice desalination of salty irrigation water to improve their operations. However, currently used desalination methods do not tailor greenhouse waters based on crop requirements. This work investigates a fully integrated desalination solution that treats and tailors brackish source waters ingreenhouses to save fertilizer and water. Specifically, this project experimentally studies multi-ion transport in and assesses the economic viable of monovalent selective electrodialysis (MSED). MSED allows for the selective removal of monovalent ions damaging to crops and the retention of divalent ions beneficial for crops, unlike the widely used reverse osmosis (RO), which removes all ions from greenhouse source water. First, we evaluate the techno-economic feasibility of MSED compared to other brackish desalination technologies for agricultural applications, based on primary market research we conduct with over 70 greenhouses.
These include conventional technologies, such as reverse osmosis (RO) and electrodialysis (ED), and advanced technologies, such as closed circuit reverse osmosis (CCRO). The analysis determines the levelized costs of water, the capital costs and energy requirements of these technologies, and how these vary with feed salinity, system capacity and recovery ratio. Then, we build a bench-scale setup to experientially characterize MSED membrane properties, including monovalent selectivity, ion transport, limiting current and resistance, for multiple brackish feedwaters and for two sets of MSED membranes: the widely used Neosepta ACS/CMS membranes and the new Fujifilm Type 16 membranes. Both MSED membranes show notable monovalent selectivity for all tested compositions, reflecting the potential of the technology for selective desalination in greenhouses. The measurements are compared to a model for MSED in multi-ion solutions. The model predicts multi-ion transport for the Neosepta and Fujifilm MSED systems within 6% and 8%, respectively.
A Review of the Water Desalination Technologies
Abstract: Desalination is commonly adopted nowadays to overcome the freshwater scarcity in
some areas of the world if brackish water or salt water is available. Different kinds of technologies
have been proposed in the last century. In this paper, the state of the mainstream solutions is
reported, showing the current commercial technologies like reverse osmosis (RO), Multi-Stages Flash
desalination (MSF) and Multi-Effect Distillation (MED), and the new frontiers of the research with
the aim of exploiting renewable sources such as wind, solar and biomass energy. In these cases,
seawater treatment plants are the same as traditional ones, with the only difference being that they
use a renewable energy source. Thus, classifications are firstly introduced, considering the working
principles, the main energy input required for the treatment, and the potential for coupling with
renewable energy sources. Each technology is described in detail, showing how the process works
and reporting some data on the state of development. Finally, a statistical analysis is given concerning
the spread of the various technologies across the world and which of them are most exploited. In this
section, an important energy and exergy analysis is also addressed to quantify energy losses.
A Review of the Water Desalination Technologies
Abstract: Desalination is commonly adopted nowadays to overcome the freshwater scarcity in
some areas of the world if brackish water or salt water is available. Different kinds of technologies
have been proposed in the last century. In this paper, the state of the mainstream solutions is
reported, showing the current commercial technologies like reverse osmosis (RO), Multi-Stages Flash
desalination (MSF) and Multi-Effect Distillation (MED), and the new frontiers of the research with
the aim of exploiting renewable sources such as wind, solar and biomass energy. In these cases,
seawater treatment plants are the same as traditional ones, with the only difference being that they
use a renewable energy source. Thus, classifications are firstly introduced, considering the working
principles, the main energy input required for the treatment, and the potential for coupling with
renewable energy sources. Each technology is described in detail, showing how the process works
and reporting some data on the state of development. Finally, a statistical analysis is given concerning
the spread of the various technologies across the world and which of them are most exploited. In this
section, an important energy and exergy analysis is also addressed to quantify energy losses.
A Primer On Brackish And Seawater Desalination
Abstract: This publication was produced as an activity of the Texas Living Waters Project. This project
is a collaborative effort of the National Wildlife Federation, Environmental Defense, and the Lone
Star Chapter of the Sierra Club. The goals of the project are to 1) ensure adequate water for people
and environmental needs, 2) reduce future demand for water and foster efficient and sustainable use
of current water supplies, 3) educate the public and decision makers about the impact of wasteful
water use and the opportunities for water conservation, and 4) involve citizens in the decision
making process for water management.
A Primer On Brackish And Seawater Desalination
Abstract: This publication was produced as an activity of the Texas Living Waters Project. This project
is a collaborative effort of the National Wildlife Federation, Environmental Defense, and the Lone
Star Chapter of the Sierra Club. The goals of the project are to 1) ensure adequate water for people
and environmental needs, 2) reduce future demand for water and foster efficient and sustainable use
of current water supplies, 3) educate the public and decision makers about the impact of wasteful
water use and the opportunities for water conservation, and 4) involve citizens in the decision
making process for water management.
A Pilot Study of an Electromagnetic Field for Control of Reverse Osmosis Membrane Fouling and Scaling During Brackish Groundwater Desalination
Abstract: This study investigated the effects of an electromagnetic field (EMF) on control of membrane
fouling and scaling during desalination of brackish groundwater using a pilot reverse osmosis (RO)
skid. The groundwater was primarily CaSO4 type with a total dissolved solids concentration of
5850 mg/L and hardness of 2500 mg/L as CaCO3. Two EMF devices were installed in the pipeline
before a cartridge filter and in the RO feed inlet to induce an electric signal of ±150 kHz to the
groundwater. The effects of EMF on membrane scaling were evaluated under accelerated conditions,
i.e., without pH adjustment and addition of antiscalant. Two-phase experiments were conducted:
Phase 1 (376 h) with the EMF devices turned on after 150 h baseline operation; and Phase 2 (753 h)
with the EMF devices turned on from the beginning of testing. The EMF significantly reduced
membrane scaling and improved RO performance by 38.3% and 14.3% in terms of normalized water
permeability decline rate after 150 h and 370 h operation, respectively. Membrane autopsy results
indicated that the fouling layer formed under the influence of EMF was loose with a low density and
was easily removed by hydraulic flushing
A Pilot Study of an Electromagnetic Field for Control of Reverse Osmosis Membrane Fouling and Scaling During Brackish Groundwater Desalination
Abstract: This study investigated the effects of an electromagnetic field (EMF) on control of membrane
fouling and scaling during desalination of brackish groundwater using a pilot reverse osmosis (RO)
skid. The groundwater was primarily CaSO4 type with a total dissolved solids concentration of
5850 mg/L and hardness of 2500 mg/L as CaCO3. Two EMF devices were installed in the pipeline
before a cartridge filter and in the RO feed inlet to induce an electric signal of ±150 kHz to the
groundwater. The effects of EMF on membrane scaling were evaluated under accelerated conditions,
i.e., without pH adjustment and addition of antiscalant. Two-phase experiments were conducted:
Phase 1 (376 h) with the EMF devices turned on after 150 h baseline operation; and Phase 2 (753 h)
with the EMF devices turned on from the beginning of testing. The EMF significantly reduced
membrane scaling and improved RO performance by 38.3% and 14.3% in terms of normalized water
permeability decline rate after 150 h and 370 h operation, respectively. Membrane autopsy results
indicated that the fouling layer formed under the influence of EMF was loose with a low density and
was easily removed by hydraulic flushing
Industrial Pretreatment Programs
Pretreatment is the reduction of the amount of pollutants, the elimination of pollutants, or the alteration of the nature of pollutant properties in wastewater prior to, or in leu of, discharging or otherwise introducing such pollutants into a POTW. The reduction or alteration may be obtained by physical, chemical or biological processes, process changes or by other means, except as prohibited by 40 CFR 403.6(d)
Industrial Pretreatment Programs
Pretreatment is the reduction of the amount of pollutants, the elimination of pollutants, or the alteration of the nature of pollutant properties in wastewater prior to, or in leu of, discharging or otherwise introducing such pollutants into a POTW. The reduction or alteration may be obtained by physical, chemical or biological processes, process changes or by other means, except as prohibited by 40 CFR 403.6(d)