Executive Summary : | Objective: Development of highly charged cation and anion-exchange membranes for electro- deionization unit. Designing of the stack, stack size (membrane area and number of cell pair) and optimization of applied potential for different grade ultra pure water. Study of hydrodynamics for turbulent flow and better process efficiency. Development of electro-deionization system for continuous production of ultrapure water with zero discharge 50 lph out put. Summary: Ultrapure water is specially purified water that has had most or all of its mineral and salt ions removed. Ultrapure water mainly produced by ion-exchange resins plant. These specially manufactured resins can be pura-fine resins, clear gel resins, or gel polystyrene resins. Mixed bed deionization is another method, in which a 50/50 mixture of cation and anion resin combined in a single ion exchange column. With proper pretreatment, product water purified from a single pass through a mixed bed ion exchange column is the purest that can be made. Most commonly, mixed bed demineralizers are used for final water polishing to clean the last few ions within water prior to use. Small mixed bed deionization units have no regeneration capability. Commercial mixed bed deionization units have elaborate internal water and regenerant distribution systems for regeneration. A control system operates pumps and valves for the regenerants of spent anions and cations resins within the ion exchange column. Each is regenerated separately, then remixed during the regeneration process. Because of the high quality of product water achieved, and because of the expense and difficulty of regeneration, mixed bed demineralizers are used only when the highest purity water is required. Ultrapure water is suitable for many applications, including autoclaves, hand-pieces, laboratory testing, laser cutting, and automotive use. Purification removes contaminants that may interfere with processes, or leave residues on evaporation. Although water is generally considered to be a good electrical conductor—for example domestic electrical systems are considered particularly hazardous to people if they may be in contact with wet surfaces—pure water is a poor conductor. The conductivity of sea-water is typically 5 S/m, drinking water is typically in the range of 5-50 mS/m, while highly purified water can be as low as 5.5 µS/m (0.055 µS/cm), a ratio of about 1,000,000:1,000:1. Ultrapure water is also used in the pharmaceutical industry. Water of this grade is widely used as a raw material, ingredient, and solvent in the processing, formulation, and manufacture of pharmaceutical products, active pharmaceutical ingredients (APIs) and intermediates, compendial articles, and analytical reagents. The microbiological content of the water is of importance and the water must be regularly monitored and tested to show that it remains within microbiological control. Major application of Ultrapure water produced by Ion Exchange Plants includes: softener, industrial Ultrapure plant, de-gasifiers, cation polisher, manual/automatic plants, pharmaceutical industry, power plant, oil & gas sector, chemical industries, textile industries etc. After producing certain volume of Ultrapure water, ion-exchange resin get discharged. Thus, regeneration of exhausted ion exchange resin, is urgently required to ensure the consistency in product Ultrapure water quality. Regeneration of ion exchange resin require. |
