The definition of a mixed bed
Mixed bed, one of the processes in the preparation of ultrapure water, isEDIUltra-pure water equipmentBefore its rise, it occupied a large share of the water treatment industry market. Due to its stable water quality (the water quality recovers quickly after mixed bed regeneration, reaching the ideal value instantly) and low cost, it has always been a process that requires ultra-pure water equipment, although it is casualEDIThe rise of ultra-pure water equipment has lost its competitive edge in high-end industries, but it still has considerable room for application in mid-to-low-end industries.

What is a mixed bed

Mixed bed is the abbreviation of mixed ion exchange column, which is a device designed for ion exchange technology. The so-called mixed bed refers to the combination of a certain proportion of positive and negative ions.Anion exchange resinThey are mixed and filled in the same exchange device to exchange and remove ions from the fluid. Because the specific gravity of the cation resin is greater than that of the anion resin, in a mixed bed, the anion resin is on top and the cation resin is at the bottom. The general ratio of anion and cation resin filling is1:2There is also a filling ratio of1:1.5For instance, different resins can be considered and selected as appropriate. Mixed beds are also divided into internal synchronous regeneration mixed beds and external regeneration mixed beds. The synchronous regeneration mixed bed operates and the entire regeneration process takes place within the mixed bed. During regeneration, the resin does not move out of the equipment, and both the cation and anion resins are regenerated simultaneously. Therefore, it requires fewer auxiliary devices and is easy to operate.

Mixed bed treatment process

The equipment for the mixed bed treatment process includes mixed ion exchangers and in vitro regeneration equipment. Among them, the in vitro regeneration equipment mainly includes resin separators and anions(Yang)Resin regenerators, resin storage towers, mixed resin towers and acid-base regeneration equipment. The main feature of the domestic mixed bed treatment process is reflected in the resin separation and regeneration process. There are three separation and regeneration processes for resins.

Advantages

1The effluent quality is excellentpHThe value is close to neutral.

2The effluent quality is stable. Short-term changes in operating conditions (such as influent water quality or composition, operating flow rate, etc.) have little impact on the effluent quality of the mixed bed.

3Intermittent operation has a small impact on the effluent quality, and the time required to restore the water quality to that before the shutdown is relatively short.

4The recovery rate reaches100%

The application of mixed beds

Mixed beds are generally placed after electrodialyzers or reverse osmosis devices (or directly applied to water with a lower salt content), and can further desalinate water to produce water of higher purity. They are widely used in industries such as electronics, chemical engineering, medicine, atomic energy, and power.

The composition and performance of mixed beds:

The materials for the mixed bed shell include fiberglass reinforced plastic, organic glass, stainless steel, carbon steel, anti-corrosion, etc. The shape is cylindrical with a diameterΦ200-2500mmThe water production volume is from0.5t/h-98t/h. The cation bed is loaded with strong acid cation exchange resin, and the anion bed is loaded with strong base anion exchange resin. The loading height is always maintained1000-2400 mmThe bottom of the small filter cap type equipment has no support layer, while the bottom of the medium and large equipment has multiple levels of quartz sand support layers of different particle sizes. The top layer of the countercurrent regeneration fixed bed resin has200 mmThick quartz sand pressed lipid layer. Operating pressure of the acrylic column≤0.15MPaOperating pressure of equipment made of other materials≤0.6MPa. The cation bed is equipped with an acid tank and an acid pump regeneration system, while the anion bed is equipped with an alkali tank and an alkali pump regeneration system.

The water quality of the effluent from the mixed-bed ultrapure water equipment≧10MΩ?CM,System recovery rate>98%Above,The service life of mixed bed resin is one or two years

The above is provided by Beijing Yuanlai Water Treatment Equipment Co., LTD., which specializes in the production and processing of water softening equipment, reverse osmosis equipment, water supply pressure stabilizing equipment, as well as the sale of water treatment accessories and consumables.