EDI is the abbreviation for its English name electrodeionization. It is a new deep desalination process that organically combines electrodialysis and ion exchange technologies. It utilizes the deep desalination capability of ion exchange to overcome the incomplete desalination defect of electrodialysis, while also leveraging the polarization-induced generation of H+ and OH- on the surfaces of electrodialysis membranes and ion exchange resins under the influence of an electric field, along with the selective permeability of electrodialysis membranes, to achieve automatic regeneration of ion exchange resins, overcoming the defect of requiring acid and alkali regeneration after resin failure. EDI is the product of the combination of ion exchange and electrodialysis technologies, thus possessing all the operational characteristics of both ion exchange and electrodialysis during the desalination process. The electrodeionization system includes the unit itself, chemical cleaning devices, auxiliary systems, supporting instruments, valves, piping systems, unit framework, and dosing equipment. The EDI unit is a key device for post-RO polishing treatment, and the EDI membrane element is the core component of the EDI unit. It is widely used in the preparation of electronic ultrapure water, industrial high-purity water, etc. It adopts a fully filled concentrate chamber, requires no salt addition or concentrate recycling, produces water continuously without the need for shutdown regeneration, and has a wider application range and superior performance. Unit design requirements: ● The electrodeionization unit adopts a frame design mode and is supplied as a complete set. The unit is equipped with all modules, rectifiers, instruments, controls, piping, valves, etc., required to meet the effluent quality and flow rate requirements. The EDI unit operates fully automatically, with internal equipment and piping arranged aesthetically. The combination of components is determined based on factors such as water quality, recovery rate, and production capacity. ● Valves are installed on the inlet and outlet main pipes of each unit of the device components. Sampling points should be set on the product water pipes and inlet/drain pipes of the device components (each device component's product water pipe should have a separate sampling point). The number and location of sampling points should effectively diagnose and identify system defects. Sampling points are centrally located for easy sampling. ● The device frame is equipped with all piping and fittings, including all supports, fasteners, clamps, etc. The combined framework of the electrodeionization unit should facilitate maintenance and disassembly. The design of the EDI unit combined frame should meet the local seismic intensity requirements. ● Types and requirements of chemical cleaning solutions. Cleaning formula, Cleaning purpose, Type, Requirement. Cleaning formula 1, Scaling/residual chemical solution, 2% hydrochloric acid, Chemically pure. Cleaning formula 2, Organic contamination, 5% NaCl + 1% NaOH, Chemically pure. Cleaning formula 3, Biological contamination/organic contamination, 0.04% peracetic acid + 0.2% H2O2, Chemically pure. ● Instruments, dosing metering pumps, and automatic valves in the electrodeionization unit use imported high-quality and reliable products. The system can achieve automatic operation. ● Each EDI module is equipped with a completely independent DC power control box, ensuring that if any module overheats due to operational reasons, the power to that module is automatically cut off, while other modules in the system continue to operate normally. ● EDI does not generate chlorine gas or salt bridges during operation. ● The EDI rectifier device meets the requirements of relevant national technical standards and displays current and voltage. ● The EDI unit adopts modular assembly for easy maintenance and replacement. Each EDI module has corresponding inlet and outlet pipes and valves, ensuring that if any module fails, it can be isolated while other modules in the system continue to operate normally. All components within the module are assembled before leaving the factory.