Drinking water quality items have greatly increased, from 35 items to 96 items
Divide the test items into conventional test items (34 items) and unconventional test items (62 items)
Improved requirements for turbidity
Oxygen consumption (permanganate index) has been added to the routine testing items of drinking water: oxygen consumption (calculated as O2) does not exceed 3mg/L, and under special circumstances it does not exceed 5mg/L.
In determining the selection and restriction of individual items of inorganic and organic matters, we should not only learn from foreign standards (WHO, EU, and the United States), but also consider China’s national conditions.
Pay attention to the hazards of disinfectants and disinfection by-products, from the original 1 item to 13 items.
More stringent requirements are put forward for some of the original project restrictions, including 4 items: turbidity, lead, cadmium, and carbon tetrachloride.
The item of fecal coliforms has been added.
2. Industrial water quality standards
3. Other important water quality standards
Environmental quality standards for surface water
Other water quality standards
3. Basic methods and basic processes of water supply treatment
1. Basic methods of water supply treatment
Remove particulate matter
Methods include: coagulation, sedimentation, clarification, air flotation, filtration, sieving (grid, screen, microfilter, filter element filter, etc.), membrane separation (microfiltration, ultrafiltration), sedimentation (coarse Sedimentation of particles), centrifugal separation (cyclone sedimentation), etc.
Treatment methods for removing and adjusting dissolved (inorganic) ions and dissolved gases in water
Treatment methods include: lime softening, ion exchange, groundwater removal of iron and manganese, redox, chemical precipitation, membrane separation (reverse osmosis, nanofiltration, electrodialysis, concentration dialysis, etc.), water quality stability (balance of dissolved ions in water, To prevent scaling and corrosion, please refer to Chapter 5 for details), defluoridation (removal of fluorine from drinking water with high fluorine water), fluorination (adding fluorine to drinking water from low fluorine water), blow-off (removal of free carbon dioxide, sulfurization) Hydrogen, etc.), aeration (oxygenation), deaeration (deoxygenation of boiler water, etc.), etc.
Treatment method to remove organic matter
Methods include: powdered carbon adsorption, raw water aeration, biological pretreatment, ozone pre-oxidation, potassium permanganate pre-oxidation, hydrogen peroxide pre-oxidation, pre-chlorination, ozone oxidation, activated carbon adsorption, biological activated carbon, membrane separation, large Porous resin adsorption (used for the removal of organic matter in the preparation of industrial pure water and high-purity water), etc.