Control system for medical purified water

 

1. Raw water quality: The raw water used for preparing medical purified water must be drinking water and regularly tested according to requirements to obtain corresponding qualified reports.

 

2. Raw water tank management: Raw water tanks need to be regularly cleaned and disinfected as required, and undergo microbiological limit, clarity, water hardness, and physicochemical testing.

 

2、 Process control

 

1. Pre treatment: Remove suspended solids, organic matter, heavy metals and other impurities from raw water through pre-treatment equipment such as multi-media filters and activated carbon filters.

 

Multi media filter: backwash, backwash, and rinse as required, regularly replace filter media, and conduct microbial limit testing.

 

Activated carbon filter: backwash and wash as required, regularly sterilize and replace, and conduct microbial limit testing. Meanwhile, activated carbon filters can adsorb organic matter and residual chloride ions in water.

 

2. Softening treatment: Using the exchangeable Na+in sodium ion resin to replace Ca2+and Mg2+in water, the raw water becomes softened water, which can effectively prevent subsequent scaling on the surface of the reverse osmosis membrane, improve the working life and treatment effect of the reverse osmosis membrane. Softened resin needs to be regenerated and effectively replenished as required, and subjected to microbial limit and water hardness testing.

 

3. Precision filtration: Use precision filters for pressure monitoring and recording, conduct microbial limit and water hardness testing on the effluent, and regularly replace the filters. Precision filters are usually composed of melt blown polypropylene (PP) membranes with a pore size of 5 μ m, which are used to prevent possible leaks in the previous filtration process and are the next processing step before the reverse osmosis membrane.

 

4. Reverse osmosis treatment: Remove impurities such as dissolved salts, colloids, microorganisms, and organic matter from water through a secondary reverse osmosis system. The secondary reverse osmosis system requires pressure and flow monitoring and recording as required, and microbial limit testing of the primary effluent. Due to the very small pore size of the reverse osmosis membrane, it can effectively remove the above-mentioned impurities with a removal rate of up to 97-98%.

 

3、 Terminal control

 

1. Control of circulation system: The inlet of the medical purified water circulation system must have qualified conductivity, harmful substances in bacteria, and physical and chemical indicators before entering the tank. Adopting sanitary grade pump circulation, with the lowest discharge point and no dead corners, the circulation flow rate meets the specified requirements (such as 1.5m/s). Perform TOC detection and UV lamp sterilization on the return water online, and regularly replace the respirator filter element and perform pure steam sterilization for conductivity and harmful substances in bacteria TOC、 Monitoring of physical and chemical indicators.

 

2. Storage management: The storage period of purified water should not exceed 24 hours, and the storage tank should be made of stainless steel material or other materials that have been verified to be non-toxic, corrosion-resistant, and do not leak out pollutant ions. A hydrophobic sterilization filter with non shedding fibers should be installed to protect its ventilation port. The inner wall of the storage tank should be smooth, and there should be no dead corners or sand holes in the connecting pipes and welds.