The core process principle of injection water purification equipment is to gradually remove impurities, ions, microorganisms, and pyrogens from water through multi-stage physical and chemical treatment, and ultimately obtain high-purity water that meets pharmacopoeia standards. The process flow is mainly divided into the following key stages:
1、 Preprocessing stage
Pre treatment is the first step in the preparation of purified water, with the aim of providing suitable water quality for subsequent deep purification. Mainly includes:
1. Multi media filtration: removes large particles such as sediment and suspended solids from water through sand filters, reducing water turbidity.
2. Activated carbon adsorption: Using the adsorption effect of activated carbon to remove residual chlorine, organic matter, and odors from water.
3. Softening treatment: Remove calcium and magnesium ions from water through ion exchange resin, reduce water hardness, and prevent subsequent equipment scaling.
2、 Reverse osmosis (RO) stage
Reverse osmosis is the core process in the preparation of purified water. Under high pressure, raw water passes through a semi permeable membrane, allowing water molecules to pass through. Almost all impurities such as inorganic salts, heavy metal ions, colloids, bacteria, and viruses are intercepted, and about 95% -99% of the salt in water can be removed. For higher water quality requirements, a two-stage reverse osmosis process can be used.
3、 Deep purification stage
To further improve water quality, the following treatment units are usually added after reverse osmosis:
1. Ion exchange: By using cation and anion exchange resins to remove residual ions from water, the electrical resistivity of the water is significantly increased. For continuous production needs, EDI (Electrodeionization) technology can be used to replace traditional ion exchange.
2. Ultrafiltration (UF): Used to remove macromolecules, bacteria, and pyrogens from water, it is one of the key steps in preparing injection water.
4、 Sterilization and storage
To ensure water quality safety, the system will be equipped with multiple sterilization devices:
1. UV sterilization: kills residual bacteria in water.
2. Pasteurization: used for regular cleaning of purified water pipelines and storage tanks to prevent microbial growth.
3. Purified water tank: made of 316L stainless steel material, used for storing produced water and providing a stable water source for water consumption points.
5、 Preparation of injection water
The quality requirements for injection water are stricter than those for purified water, and its preparation methods mainly include:
1. Distillation method: Heating and evaporating purified water, condensing the steam to obtain distilled water, and if necessary, conducting secondary distillation to remove the heat source.
2. Reverse osmosis method: Purified water is efficiently removed of ions and microorganisms by passing it through a reverse osmosis membrane under high pressure.
3. Comprehensive method: combining multiple technologies (such as reverse osmosis+distillation) to optimize water quality.
The entire system adopts modular design and is automatically controlled by PLC to ensure stable water quality. The final produced water must comply with the electrical resistivity and other parameter standards specified in the Chinese Pharmacopoeia.