Sigma Enviro offer Reverse Osmosis Plants setup. Reverse osmosis (RO) is a membrane-technology filtration method that removes many types of large molecules and ions from solutions by applying pressure to the solution, when it is on one side of a selective membrane.
The result is that the solute is retained on the pressurized side of the membrane and the pure solvent is allowed to pass to the other side. To be “selective,” this membrane should not allow large molecules or ions through the pores (holes), but should allow smaller components of the solution (such as the solvent) to pass freely. Reverse osmosis is used to purify Water and remove salts and other impurities in order to improve the color, taste or properties of the fluid.
Design Considerations for RO Plant
Fluid Systems RO Plants work on the Crossflow Filtration method, which takes the feed water and uses a percentage of it as a wash or reject stream, removing the solids during the filtration process.
The product flow of an RO Plant is mainly a function of temperature and pressure. System recovery (product divided by feed) is limited by the characteristics of the feed water and can be controlled through the use of recycle stream. Product quality is based on a percentage of dissolved solids fed to the membrane. There should be an economic balance between product quality and system recovery. High recoveries increase concentration of dissolved solids in the system which degrades quality, but high recoveries make the system work more efficiently and decrease waste.
Reverse Osmosis Plants do not deliver to service all of the water that is fed to them. During operation, some of the incoming water is used to wash down the membrane, and only part becomes finished product water. Purified water is referred to as product and wastewater is referred to as concentrate, or reject. The percent of water delivered as product is called the recovery, and depends upon the membrane and on total RO Plant design considerations.
Pretreatment - Reverse Osmosis Plants
The feed water, depending on its source, may contain various concentrations of suspended solids and dissolved matter. Suspended solids may consist of inorganic particles, colloidal particles and biological impurities such as microorganisms and algae. Dissolved matter may consist of highly soluble salts, such as chlorides, and sparingly soluble salts, such as carbonates, sulfates, and silica.
During the Reverse Osmosis process, the volume of feed water decreases, and the concentration of suspended particles and dissolved ions increases. Suspended particles may settle on the membrane surface, thus blocking feed channels and increasing pressure drop across the system. Sparingly soluble salts may precipitate from the concentrate stream, create scale on the membrane surface, and result in lower water permeability through the RO membranes. This process of formation of a deposited layer on a membrane surface is called membrane fouling and results in performance decline of the RO system. The objective of the feed water pretreatment process is to improve the quality of the feed water to the level which would result in reliable operation of the RO membranes. Based on the raw water quality, the pretreatment process for RO Plants may consist of all or some of the following treatment steps: • Clarification followed by Sand Filtration for Turbidity removal
• Water disinfection with chlorine
• Hardness reduction by Softening
• Addition of scale inhibitor
• Reduction of free chlorine using sodium bisulfite/ Activated carbon filters
• Final removal of suspended particles using cartridge filters
RO Plants - Post Treatment
Based on the Output water quality required, the post treatment process for Reverse Osmosis Plants may consist of all or some of the following treatment steps
• chlorination systems
We Offer a wide range of Reverse Osmosis Plants [RO Plants]
Commercial RO Systems / Institutional RO Systems
One of our most popular series, the Commercial RO usually comes in standard Models. These Commercial RO Systems can be customized to add Multimedia Filters & Activated carbon Filters, Water softeners, Antiscalant Dosing Systems, and UV sterilizers.
These systems are used to purify water and remove salts and other impurities. It is also capable of rejecting bacteria
The Main features of these RO Plants are:
• Microprocessor based Control Panel
• Powder coated frame
• 20 & 5 micron sediment pre-filter
• Stainless Steel Multistage High pressure pump
• FRP pressure vessel
• Product and Reject Flow Meters
• Low & High pressure switch
• High rejection TFC membranes
• Heavy duty high pressure tubing
• Pressure gauges