Abstract: A photovoltaic-thermal (PV-T) system and a method of cooling photovoltaic (PV) cells in the system is described herein. Energy from an excitation source such as the sun hits the PV cells in the PV-T system causing heating that reduces PV efficiency. The PV cells are cooled by fluid in an intact heat-transfer system making a heated water byproduct while the PV cells release a form of energy. In addition, the PV-T system can be implemented in a desalination plant to harvest energy and heat for desalination processes. The present invention also includes methods for transferring heat from PV cells to the earth to improve PV performance and reduce thermal shock to the PV cells.

Abstract: The present invention provides counter flow cascade separation systems useful to separate solute/solute pairs present in a solvent. The separation systems include a series of interconnected stages with each stage comprising a diafilter preferentially permeable for one solute. Solute/solute pairs are preferentially separated by the diafilter into permeate and retentate flows. Stages are combined to form separation systems capable of operation approaching an ideal cascade.

Abstract: The present invention describes a system and method for accurately measuring the concentration of a substance within a filter housing. A concentration sensor and a communications device are coupled so as to be able to measure and transmit the concentration of a particular substance within the filter housing while in use. This system can comprise a single component, integrating both the communication device and the concentration sensor. Alternatively, the system can comprise separate sensor and transmitter components, in communication with one another. In yet another embodiment, a storage element can be added to the system, thereby allowing the device to store a set of concentration values. The use of this device is beneficial to many applications. For example, the ability to read concentration values in situ allows integrity tests to be performed without additional equipment.

Abstract: Disclosed is a system for reducing the demand of wastewater volume flowing through a wastewater collection piping system and thereby increasing the effective capacity of the system. A portion of the wastewater is diverted from a sewer main. The solids are separated from the liquid, for example, by a vortex separator. The recovered liquid can be treated and made available for reuse or can be disposed of, for example, in a body of water or pumped into the ground. The concentrated solids are reintroduced into the main sewage line in a portion that adjusts the wastewater loading in the sewer main to a predetermined amount or predetermined range. Also disclosed is a system capable of reintroducing the concentrated solids into the sewer main in a portion that adjusts the solids loading in the sewer main to a predetermined amount or predetermined range.

Abstract: An apparatus and methods for producing purified drinking water are disclosed. A hand pump is used in a closed system to generate pressure sufficient to pass the untreated water through a system of filters and a reverse osmosis membrane. The system preferably includes an ultrafiltration filter. The resulting water is substantially pure, being free of bacteria and having a significant amount of minerals and salts removed to make it safe for drinking. The system can produce enough potable water to supply the daily needs for a small village.

Abstract: The present invention describes a system and method for accurately measuring the concentration of a substance within a filter housing. A concentration sensor and a communications device are coupled so as to be able to measure and transmit the concentration of a particular substance within the filter housing while in use. This system can comprise a single component, integrating both the communication device and the concentration sensor. Alternatively, the system can comprise separate sensor and transmitter components, in communication with one another. In yet another embodiment, a storage element can be added to the system, thereby allowing the device to store a set of concentration values. The use of this device is beneficial to many applications. For example, the ability to read concentration values in situ allows integrity tests to be performed without additional equipment.

Abstract: A process of producing a structure for molecular separations includes providing a plurality of template materials. The template materials are selected from biomolecules, biopolymers, polymers, or combinations thereof. A sieve material, suitable for producing a structure for molecular separations, is provided around the template materials. The template materials are positioned in an arrangement for leaving pores suitable for molecular separations. The template materials are removed to leave pores in the sieve material and produce the structure suitable for molecular separations.

Abstract: A method of making a porous membrane is disclosed. One such method optionally includes: forming a plurality of pillars in an array form over a substrate; and forming a layer with a mixture of a porous material precursor and a surfactant over the substrate. The method optionally includes removing the pillars to leave cavities in the layer; filling the cavities in the layer with a cavity filler; and removing the surfactant from the layer. The porous membrane can be used as, for example, a sieve for separating molecules from a chemical reaction.

Abstract: In the present invention high performance cross-linked polybenzoxazole and polybenzothiazole polymer membranes and methods for making and using these membranes have been developed. The cross-linked polybenzoxazole and polybenzothiazole polymer membranes are prepared by: 1) first synthesizing polyimide polymers comprising pendent functional groups (e.g., —OH or —SH) ortho to the heterocyclic imide nitrogen and cross-linkable functional groups in the polymer backbone; 2) fabricating polyimide membranes from these polymers; 3) converting the polyimide membranes to polybenzoxazole or polybenzothiazole membranes by heating under inert atmosphere such as nitrogen or vacuum; and 4) finally converting the membranes to high performance cross-linked polybenzoxazole or polybenzothiazole membranes by a crosslinking treatment, preferably UV radiation. The membranes can be fabricated into any convenient geometry.

Abstract: The present invention provides methods for producing salinity power using pressure retarded osmosis and a biometric membrane (e.g., a liquid bilayer membrane or a lipid membrane containing multiple bilayers of fused deposited lipid vesicles) containing aquaporin water channels. The invention also provides power plants for producing salinity energy using pressure retarded osmosis and a biometric water membrane containing functional aquaporin channels.

Abstract: The present invention is directed to a membrane for aromatics separation that is stable in an alcohol containing environment. The polymeric membrane is a epoxy amine based membrane.

Abstract: Disclosed is a method of purifying fluid, typically an aqueous fluid steam, with the method involving at least two reverse osmosis stages with retentate from a first reverse osmosis stage being subjected to the second reverse osmosis stage, and with intermediate treatment of retentate from the first reverse osmosis stage by exposure to an electric field. The intermediate treatment may involve electrocoagulation to remove sparingly-soluble compounds and permit enhanced reverse osmosis recovery. Additional treatment may be performed prior to the first reverse osmosis stage, between the first reverse osmosis stage and the intermediate treatment with an electric field, between such intermediate treatment and the second reverse osmosis stage, or after the second reverse osmosis stage.

Abstract: Systems and methods for osmotically assisted desalination include using a pressurized concentrate from a pressure desalination process to pressurize a feed to the desalination process. The depressurized concentrate thereby produced is used as a draw solution for a pressure-retarded osmosis process. The pressure-retarded osmosis unit produces a pressurized draw solution stream that is used to pressurize another feed to the desalination process. In one example, the feed to the pressure-retarded osmosis process is impaired water.

Abstract: An electrically-driven separation apparatus can be used with a pressure-driven separation apparatus to provide potable water having a desired total dissolved solids (TDS).

Abstract: Prior water treatment equipments have several water clarifying process filters, water purifier and water reservoir separated from each other, occupying too much space to install under a water tank and resulting inconvenient installment. The water treatment equipments for home cannot be received in water tanks, and thus water clarifier and water purifier are disposed in the water tanks while the water reservoir is disposed separately. Water pipes are connected in between. Therefore, water clarifying processors, water reservoir and water purifier utilizing RO membrane may be integrated to eliminate unnecessary space in existing systems.

Abstract: A flow-switch controlled, zero waste reverse osmosis water treatment system having a first conduit for providing a supply of water, a second conduit having an inlet in fluid communication with the first conduit for selectively receiving a flow of water from the first conduit, a reverse osmosis element positioned along the second conduit, the reverse osmosis element separating the flow of water within the second conduit into a purified water stream and a reject water stream, a purified water conduit having an inlet configured to receive the purified water stream and a reject water conduit having an inlet configured to receive the reject water stream and an outlet in fluid communication with the first conduit.

Abstract: The present invention relates to surface modification of reverse osmosis membranes to introduce antifouling properties without compromising the separation properties of the original membranes. This approach utilizes: providing a coated membrane surface having enhanced hydrophilic characteristics that prevents the biofoulants from settling; have a surface that consists of hydrophilic brushes that unsettle any biofoulants that get through; and having antimicrobial ions present in the membrane coatings and able to remove or minimize any remaining biofoulants without leaching into the permeate. These coatings are made using dendritic polymers such as hyperbranched polymers or dendrimers.

Abstract: A pre-treatment method for cleaning and maintaining reverse osmosis membrane filters by injecting sulfurous acid into waters with suspended solids in a liquid fraction to be filtered to form sulfurous acid (H2SO3) to acid leach heavy metals into the liquid fraction, reduce alkalinity and mineral scaling, add sufficient SO2 as a biocide to attack bacteria and other micro organisms to prevent membrane fouling, reduce iron to prevent iron deposit build-up, scavenge and remove dissolved oxygen prior to filtration to prevent membrane oxidation, and then sequentially filtering the acidified water through membrane filters to create a metal free permeate and a brine retentate, which can be pH adjusted to remove the heavy metals as metal hydroxide precipitates.

Abstract: Disclosed is a system for reducing the demand of wastewater volume flowing through a wastewater collection piping system and thereby increasing the effective capacity of the system. A portion of the wastewater is diverted from a sewer main. The solids are separated from the liquid, for example, by a vortex separator. The recovered liquid can be treated and made available for reuse or can be disposed of, for example, in a body of water or pumped into the ground. The concentrated solids are reintroduced into the main sewage line in a portion that adjusts the wastewater loading in the sewer main to a predetermined amount or predetermined range. Also disclosed is a system capable of reintroducing the concentrated solids into the sewer main in a portion that adjusts the solids loading in the sewer main to a predetermined amount or predetermined range.

Abstract: A method and system for purifying production water obtained from oil and gas operations so that the purified water need not be disposed of by forced injection back into the geological formation but can be put to a beneficial use such as agriculture, irrigation, industrial or municipal or potable applications. The production water is treated in a ceramic microfilter after it has been pretreated (preferably by aeration and with a walnut shell filter) to remove volatile hydrocarbons and heavier oils, such as paraffins and asphaltenes, that could foul the ceramic filter. The permeate from the ceramic microfiltration can then be treated with activated charcoal or otherwise treated to meet the specific requirements for the intended beneficial use.

Abstract: A multi-ported vessel system includes an outer pressure vessel containing a plurality of flow distribution tubes, each of which comprises a plurality of reverse osmosis membrane elements aligned serially within each tube. The outer pressure vessel includes bypass flow paths whereby feed water flows around each of the tubes within the vessel. Slots are disposed in the flow distribution tubes at the upstream end of each RO membrane element such that feed water reaches all RO membrane elements of the tubes in parallel. The serial alignment of the membranes also allows for serial water processing also. A product water tube collects the purified water from the reverse osmosis elements and provides it to a product water port. Brine water is provided to an output port to be discarded of for further processing. The parallel processing of feed water by all membrane elements results in increased productivity and reduced costs.

Abstract: This invention relates to the fabrication of a polymeric membrane and a process for utilizing the polymeric membrane for separating components of a feedstream. More particularly, but not by way of limitation, this invention relates to the fabrication of a polymeric membrane and a process for utilizing the polymeric membrane in the separation of aromatics from a hydrocarbon based feedstream. The membranes of the present invention possess low soft segment glass transition temperatures and improved separation characteristics.

Abstract: The present disclosure provides methods and systems for purifying liquids. In a particular implementation, the system includes a forward-osmosis unit for diluting a water source for a downstream desalination unit. A pretreatment unit may be located hydraulically upstream of the desalination unit, such as upstream or downstream of the forward-osmosis unit. In certain embodiments, the system includes an extraction unit for extracting a relatively easily extractable osmotic agent from an osmotic draw solution. The system may include one or more forward-osmosis units downstream of the desalination unit for diluting a concentrated brine stream produced by the desalination unit. In particular embodiments, a downstream forward-osmosis unit uses the concentrated brine stream as an osmotic agent, such as to extract water from seawater or brackish water. Another downstream forward-osmosis unit may use impaired water as a feed stream.

Abstract: The present invention describes a system for accurately measuring the concentration of a substance within a filter housing. A concentration sensor and a communications device are coupled so as to measure and transmit the concentration of a particular substance within the filter housing while in use. This system allows the operator to certify the integrity of the filters within the filter housing at the customer site without additional equipment. In one embodiment, a tracer gas, such as helium or hydrogen, is added to a carrier and injected into the system. The concentration of tracer gas at a specific operating transmembrane pressure is indicative of bubble pointing specific pores in the filter. This test will give a more sensitive indication of the bubble point and the presence of defects than a standard diffusion test. In a second embodiment, two gasses, in a known ratio, are introduced into the filter housing.

Abstract: An object is to provide a fresh water generating method that is capable of efficiently producing purified water, such as fresh water, from unpurified water, such as sea water. Provided is a fresh water generating method for generating fresh water by way of reverse osmosis membrane filtration, which includes mixing sea water with low salt concentration water having a salt concentration lower than sea water to produce mixed water, and subjecting the mixed water prepared by the mixing to reverse osmosis membrane filtration, thereby generating fresh water.

Abstract: Disclosed herein are systems and methods for desalination of salt water based on an engineered acoustic field that causes constructive and destructive interference at pre-computed spatial positions. The engineered acoustic field can cause high-pressure and low-pressure regions where desalination membranes are located. The induced pressure from the acoustic field can force pure water through the membranes leaving ionic and dissolved molecular species behind.

Abstract: Dialysis treatment devices and methods for removing urea from dialysis waste streams are provided. In a general embodiment, the present disclosure provides a dialysis treatment device including: 1) a first filter having a filtration membrane, 2) a urea removal unit having urease and in fluid communication with the first filter, and 3) a second filter having an ion rejection membrane and in fluid communication with the first filter and the urea removal unit.

Abstract: A desalination system is provided that may be operated in a self-sustained fashion. The desalination system is comprised of (i) a wind turbine; (ii) an air compressor coupled to, and powered by, the wind turbine; (iii) a compressed air storage tank for storing the pressurized air from the air compressor; (iv) a pneumatic actuator that is powered by compressed air stored in the air storage tank; (v) at least one compression cylinder coupled to, and powered by, the pneumatic actuator; (vi) a source of salt water that is introduced into the compression chamber(s) of the compression cylinder(s); and (vii) a reverse osmosis desalination column that is configured to receive pressurized salt water from the compression cylinder(s) and output desalinated water.

Abstract: A system for treating feedwater includes a fluidized bed heat exchanger unit connected to receive feedwater and a flash concentrator column connected to receive feedwater discharged from the fluidized bed heat exchanger unit. A spray dryer is provided to receive a solids/liquid slurry discharged from the flash concentrator column. Feedwater can be treated by converting dissolved solids in the feedwater to suspended solids, vaporizing a portion of the feedwater to produce a solids/liquid slurry, and separating solids from the solids/liquid slurry.

Abstract: This invention is directed to an integrated process and system for water treatment, in particular, an integrated process and system for water treatment in the beverage manufacture cycle. The water treatment process is directed to treating an influent water solution, a low sugar concentration solution, and a high sugar concentration solution. The water treatment system is directed to a system for treating an influent water solution, a system for treating a low sugar concentration solution, and system for treating a high sugar concentration solution.

Abstract: Disclosed is a treatment apparatus capable of inhibiting growth of microorganisms and carrying out long-term stable treatment in an activated carbon tower and a reverse osmosis membrane separation device during processes including activated carbon treatment and RO membrane separation treatment of a later step in a system for manufacturing ultrapure water used in an electronic device factory.

Abstract: Certain disclosed embodiments concern systems and methods of preparing dialysate for use in a home dialysis system that is compact and light-weight relative to existing systems and consumes relatively low amounts of energy. The method includes coupling a household water stream to a dialysis system; filtering the water stream; heating the water stream to at least about 138 degrees Celsius in a non-batch process to produce a heated water stream; maintaining the heated water stream at or above at least about 138 degrees Celsius for at least about two seconds; cooling the heated water stream to produce a cooled water stream; ultrafiltering the cooled water stream; and mixing dialysate components into the cooled water stream in a non-batch process.

Abstract: An object is to provide a fresh water generating method that is capable of efficiently producing purified water, such as fresh water, from unpurified water, such as sea water. Provided is a fresh water generating method for generating fresh water by way of reverse osmosis membrane filtration, which includes mixing sea water with low salt concentration water having a salt concentration lower than sea water to produce mixed water, and subjecting the mixed water prepared by the mixing to reverse osmosis membrane filtration, thereby generating fresh water.

Abstract: An object is to provide a fresh water generating method that is capable of efficiently producing purified water, such as fresh water, from unpurified water, such as sea water. Provided is a fresh water generating method for generating fresh water by way of reverse osmosis membrane filtration, which includes mixing sea water with low salt concentration water having a salt concentration lower than sea water to produce mixed water, and subjecting the mixed water prepared by the mixing to reverse osmosis membrane filtration, thereby generating fresh water.

Abstract: An object is to provide a fresh water generating method that is capable of efficiently producing purified water, such as fresh water, from unpurified water, such as sea water. Provided is a fresh water generating method for generating fresh water by way of reverse osmosis membrane filtration, which includes mixing sea water with low salt concentration water having a salt concentration lower than sea water to produce mixed water, and subjecting the mixed water prepared by the mixing to reverse osmosis membrane filtration, thereby generating fresh water.

Abstract: An SWRO module for use in a desalination plant receives refresh water to increase production and product quality and reduce scaling problems. The SWRO module includes a pressure vessel having a front-end feed port, a rear-end brine port and a rear-end permeate port. A plurality of RO membrane elements are located in series within the pressure vessel. At least one refresh port leading to an interconnector mixing zone within the pressure vessel is located between two of the plurality of RO membrane elements. The port is configured such that refresh water added to the SWRO module through the refresh port mixes with the feed water supplied through the front-end feed port in the interconnector mixing zone.

Abstract: Disclosed is a system for reducing the demand of wastewater volume flowing through a wastewater collection piping system and thereby increasing the effective capacity of the system. A portion of the wastewater is diverted from a sewer main. The solids are separated from the liquid, for example, by a vortex separator. The recovered liquid can be treated and made available for local reuse. The concentrated solids are reintroduced into the main sewage line in a portion that adjusts the wastewater loading in the sewer main to a predetermined amount or predetermined range. Also disclosed is a system capable of reintroducing the concentrated solids into the sewer main in a portion that adjusts the solids loading in the sewer main to a predetermined amount or predetermined range.

Abstract: A process of obtaining a natural, bioactive concentrate, rich on hydroxytyrosol, from olive tree residues and subproducts using clean technologies is presented. These technologies comprise supercritical fluid extraction, nanofiltration and reverse osmosis which are used individually or in an integrated mode. The natural extract comprises hydroxytyrosol at a minimum concentration of 15% (mass fraction) and a maximum concentration of 98% (mass fraction). The hydroxytyrosol-rich concentrate exhibits anti-oxidant, anti-microbial, anti-inflammatory and anti-carcinogenic activities, which are superior to the activities observed for isolated hydroxytyrosol in equivalent concentration. The hydroxytyrosol-rich concentrate can be prepared in the form of solid particles, as an aqueous solution, in an emulsion or as lipidic based nanoparticles. Industrial application includes the food, pharmaceutical and cosmetics industries.

Abstract: A method and components for heating and hydrating foods and beverages using an exothermic and pressure generating chemical reaction are described. The exothermic reaction can be initiated by water, spark, electrical impulse, squib, friction, or shock to heat non-potable water and force the water through a membrane filter, thereby producing heated, potable water.

Abstract: An object is to provide a fresh water generating method that is capable of efficiently producing purified water, such as fresh water, from unpurified water, such as sea water. Provided is a fresh water generating method for generating fresh water by way of reverse osmosis membrane filtration, which includes mixing sea water with low salt concentration water having a salt concentration lower than sea water to produce mixed water, and subjecting the mixed water prepared by the mixing to reverse osmosis membrane filtration, thereby generating fresh water.

Abstract: Disclosed is a system for reducing the demand of wastewater volume flowing through a wastewater collection piping system and thereby increasing the effective capacity of the system. A portion of the wastewater is diverted from a sewer main. The solids are separated from the liquid, for example, by a vortex separator. The recovered liquid can be treated and made available for local reuse. The concentrated solids are reintroduced into the main sewage line in a portion that adjusts the wastewater loading in the sewer main to a predetermined amount or predetermined range. Also disclosed is a system capable of reintroducing the concentrated solids into the sewer main in a portion that adjusts the solids loading in the sewer main to a predetermined amount or predetermined range.

Abstract: Systems and methods for lowering levels of carbon dioxide and other atmospheric pollutants are provided. Economically viable systems and processes capable of removing vast quantities of carbon dioxide and other atmospheric pollutants from gaseous waste streams and sequestering them in storage-stable forms are also discussed.

Abstract: A hollow fiber includes a lumen, a polymeric membrane defining the lumen, and a porous tubular substrate, a circumferential surface of which is in contact with a circumferential surface of the polymeric membrane. The polymeric membrane includes a first polymer having monomers each containing an imidazole group.

Abstract: Disclosed is an economical process for the purification of water containing soluble and sparingly soluble inorganic compounds using single-stage or two-stage membrane processes that integrate membrane water purification with chemical precipitation softening and residual hardness and silica removal from the membrane concentrates using ion exchange resins and silica sequestering media, respectively. The purified water recovery in the present invention will not be adversely affected by design and/or operational deficiencies in the chemical precipitation softening system that may result in higher residual hardness and silica in the supernatant from the clarifier.

Abstract: A method for disposing of carbon dioxide is provided. According to the invention, CO2 is dissolved in seawater and the salinity of the seawater is increased to produce CO2-containing brine. The CO2-containing brine is denser than the seawater from which it is made. Therefore, when it is released into the ocean, the CO2-containing brine sinks to depth and sequesters the carbon dioxide. The brine may be produced by forming CO2 hydrate, which extracts fresh water from the seawater. Alternatively, the brine may be produced by forming water ice from the seawater and injecting CO2 into the seawater either before or, more preferably, after the water ice has been formed.

Abstract: Methods and systems for a zero discharge waste water treatment system are provided. The system includes a filtration train including filter media having successively smaller diameter filtration elements, a reverse osmosis apparatus including a pump and a membrane coupled in flow communication with said filtration train, a vapor compressor coupled in flow communication with said reverse osmosis apparatus, and a spray dryer coupled in flow communication with said vapor compressor, said spray dryer configured to separate moisture in a brine solution from particulate suspended in the brine solution.

Abstract: The invention relates to a process for separating, in an aqueous medium, at least one actinide element from one or more lanthanide elements by using at least one molecule which sequesters the said actinide element to be separated and membrane filtration, the said process successively comprising: a) a step of bringing at least one molecule which sequesters the said actinide element in contact with the aqueous medium, the said molecule not being retained in the non-complexed state by the said membrane and being capable of forming a complex with the actinide element to be separated, comprising the said element and at least two of the said sequestering molecules, which complex is capable of being retained by the membrane; b) a step of passing the aqueous medium over the membrane in order to form a permeate on one side, comprising an aqueous effluent depleted of the said actinide element, and a retentate comprising the said complex.

Abstract: Nanoporous membranes comprising single walled, double walled, and multiwalled carbon nanotubes embedded in a matrix material were fabricated for fluid mechanics and mass transfer studies on the nanometer scale and commercial applications. Average pore size can be 2 nm to 20 nm, or seven nm or less, or two nanometers or less. The membrane can be free of large voids spanning the membrane such that transport of material such as gas or liquid occurs exclusively through the tubes. Fast fluid, vapor, and liquid transport are observed. Versatile micromachining methods can be used for membrane fabrication. A single chip can comprise multiple membranes. These membranes are a robust platform for the study of confined molecular transport, with applications in liquid and gas separations and chemical sensing including desalination, dialysis, and fabric formation.

Abstract: In one embodiment, the present invention includes a liquid processing system. In the liquid processing system, a first liquid source transmits feed liquid to a heat exchange unit while a heat generation unit transmits warm coolant to the heat exchange unit. A heat generation unit warms the feed liquid while cooling the warm coolant. The warmed feed liquid is sent to a pump, and cooled feed liquid from a second liquid source is mixed with the warmed feed liquid as necessary until a target temperature is reached. The warmed feed liquid is sent to a reverse osmosis unit for filtering and the resulting permeate is sent to the liquid utilization unit. The cooled coolant is sent from the heat exchange unit to the storage tank and if the cooled coolant is not cool enough, it is sent to a cooling tower for further cooling.

Abstract: Included is a high-pressure pump P1 that increases the pressure of raw water 11 to a predetermined high pressure, a high-pressure reverse osmosis device 13 including a high-pressure reverse osmosis membrane 13a for concentrating a salt content in high-pressure feed water 12 whose pressure is increased, a first drain valve 21 that is mounted on a permeated water line L2 for supplying the permeated water 14 downstream and temporarily drains permeated water 14 of an initial start-up from a discharge line L6, a low-pressure pump P2 that is mounted on a permeated water line L3 provided downstream of the first drain valve 21 and reduces the pressure of the permeated water 14 to a predetermined low pressure, a low-pressure reverse osmosis device 16 including a low-pressure reverse osmosis membrane 16a for concentrating a salt content in low-pressure feed water 15 whose pressure is reduced by the low-pressure pump P2, and a second drain valve 22 that is mounted on a discharge line L5 at the concentrated water side of