(I)Product Overview
EDI electric deionization ultra pure water equipment belongs to continuous deep desalination water production equipment that does not require acid-base regeneration. It combines the dual mechanism of ion exchange resin and electrodialysis electrochemistry, and can further refine the reverse osmosis RO effluent to produce ultrapure water. It is a key terminal unit of high-end industrial pure water systems.
The equipment uses reverse osmosis water as the inlet and relies on the electric field to drive the directional migration of anions and cations in the water to achieve desalination. At the same time, it completes the online self regeneration of the resin and can stably produce high-purity ultrapure water with a resistivity of ≥ 15M Ω· cm. Widely applicable to electronic semiconductors, lithium batteries, photovoltaics, research laboratories, pharmaceuticals, medical devices, precision electroplating, etc TOC、 Industries with strict requirements for silicon content indicators can replace traditional mixed bed processes to achieve green and environmentally friendly, fully automatic continuous water production.
(II) Core product features
1. Free from acid-base regeneration, green economy operation eliminates the traditional mixed bed operation mode relying on hydrochloric acid and sodium hydroxide for regeneration, does not generate acid-base waste liquid, saves the expenses of drug procurement, storage, and waste liquid neutralization and disposal, and avoids the operational safety hazards caused by chemicals.
2. Continuous outflow of water, stable water quality performance, uninterrupted production of ultrapure water can be achieved by powering on. Equipment start-up and shutdown will not cause sudden changes in water quality, and the effluent resistivity remains stable at 10.18.2M Ω· cm, which can efficiently remove trace ion impurities such as silicon, heavy metals, and nitrates.
3. Highly automated, with low maintenance burden, equipped with online monitoring modules for resistivity, flow rate, pressure, and conductivity of concentrated water, which can automatically regulate the reflux and production flow of concentrated water; Resin relies on an electric field for in-situ regeneration, without the need for manual disassembly or replacement of resin fillers.
4. Energy saving and water-saving, small space occupation, long service life. The EDI membrane stack adopts a standard modular structure and supports single or multiple parallel expansion; The working voltage of the module is low, and the power consumption is low. The concentrated water can be recycled back to the front end of the reverse osmosis system, and the comprehensive water recovery rate can reach 85% 95%. The water resource loss is much better than that of traditional mixed beds. The service life of the membrane stack can reach 23 years, and the pipeline and self-control components have excellent corrosion resistance, with a longer maintenance cycle.
5. Low TOC and low silicon effluent, suitable for high-end processes to efficiently remove soluble silicates and organic ions, meeting the strict ultrapure water standards of the photovoltaic, chip, and lithium battery industries, and avoiding blockage and failure of backend precision equipment caused by silicon and water scales.
6. Anti corrosion insulation, suitable for special working conditions. The water passing components are made of UPVC, PVDF, 316L stainless steel materials, and the electrodes are designed with insulation protection to eliminate the risk of leakage. It can be applied to complex production environments such as clean workshops and explosion-proof workshops.
(III) Complete system composition
The EDI ultra pure water system mainly consists of four functional modules: pre-processing unit, EDI host unit, automatic monitoring unit, and auxiliary circulation recovery unit.
1. The pre-processing unit (EDI inlet protection system) EDI has very strict inlet conditions, and this unit is responsible for producing standard reverse osmosis water to ensure the stable operation of EDI.
Reverse osmosis RO host: optional first or second stage reverse osmosis process, capable of removing over 99% of inorganic salts, colloids, and suspended particles;
Security filter (5 μ m/1 μ m): intercepts debris and small impurities from the reverse osmosis membrane to avoid scratching the EDI membrane stack components;
Activated carbon filter/TOC removal device: reduce the total organic carbon content in the influent to avoid resin contamination by organic matter;
PH adjustment device: Control the pH of the incoming water at 7.0 and 9.0 to optimize the desilication performance of the EDI system;
Boosting and stabilizing pump: Stabilize the inlet pressure to ensure uniform and consistent inlet flow for each membrane stack.
2. EDI host core unit (ultra pure water production core)
EDI membrane stack (core component): assembled by a combination of cation exchange membrane, concentrated water separator, fresh water separator, ion exchange resin, and positive and negative electrode plates. Internally divided into fresh water chamber, concentrated water chamber, and extreme water chamber; The fresh water chamber produces ultrapure water, the concentrated water chamber collects enriched ion wastewater, and the electrode water chamber discharges the wastewater generated by electrode reactions.
DC stabilized power supply: outputs an adjustable DC voltage of 0 300V, providing electric field power for ion migration and resin self regeneration.
Water production, concentrated water, and extreme water pipelines: PVDF corrosion-resistant pipelines are used, and the three water bodies circulate independently.
Concentrated water circulation booster pump: increases the water flow velocity in the concentrated water chamber, suppresses ion enrichment, and reduces the risk of scaling.
3. Online monitoring and automatic control unit
Online resistivity meter: Real time monitoring of water quality, automatic alarm and switching of drainage when water quality exceeds the standard;
Conductivity meter: Collect conductivity data of concentrated water and extreme water to determine the actual desalination efficiency of the membrane stack;
Pressure sensors and flow transmitters: collect pressure and flow parameters of incoming water, produced water, and concentrated water;
PLC control cabinet with touch screen: realizing automatic start stop of equipment, safety interlock protection, fault alarm, and operation data storage and recording;
Electromagnetic valve and automatic directional valve: When the water quality does not meet the standard, it automatically flows back to the original water tank to prevent unqualified water from being supplied to the back end for use.
4. Auxiliary recycling and water storage unit
Ultra pure water tank: equipped with nitrogen sealing device, breathing valve, UV sterilization to prevent secondary pollution of ultra pure water;
Concentrated water recovery pipeline: EDI concentrated water flows back to the reverse osmosis raw water tank for reuse, improving the overall water utilization rate;
UV sterilizer and ultra purification column (equipped with advanced processing components at the back end): further reducing TOC and microbial content;
Circulating conveying pump: realizes the circulation of workshop water pipeline, avoiding the retention of pure water in the pipeline and causing water quality degradation.
