What is the water treatment process?

First, the commonly used water treatment method

Common water supply treatment method

Natural precipitation to remove coarse particulate impurities in water

Coagulation and sedimentation using a coagulating agent to precipitate or clarify the removal of colloids and suspended impurities in the water to filter water to pass through the fine pore filter layer, to remove the fine impurities remaining after precipitation or clarification; or to directly add the raw water without precipitation. Coagulation, filtration, removal of colloids and suspended impurities in water to eliminate viruses and bacteria in water, ensure safe drinking water sanitation and production water, reduce calcium and magnesium ion content in water, soften water, remove iron and manganese, and remove excess iron and manganese from groundwater. To meet the drinking water requirements

Second, the water treatment process and applicable conditions

Common processing procedures and applicable conditions

Process conditions

Simple treatment of raw water (such as screen filtration or disinfection)

Raw water-contact filtration - disinfection is generally used to treat lake water and reservoir water with low turbidity and chroma. Influent suspended solids are generally less than l00mg/L, water quality is stable, small change and no algae reproduction

Raw water-coagulation, sedimentation or clarification-filtration-disinfection The general treatment process widely used in surface water treatment plants is suitable for turbidity less than 3mg/L river water. The turbidity of river creeks is often low, and the amount of sand contained in floods is large. This procedure can be used to directly filter low turbidity and non-polluting water without coagulant or across sediments.

Pre-sinking of raw water - natural pre-precipitation or coagulation sedimentation - coagulation sedimentation or clarification - filtration - disinfection of high turbidity water secondary precipitation, suitable for large sand content, long sand peak duration, raw water after pre-sinking The sand content should be reduced to less than 1000mg/L. The small and medium-sized water plants in the middle and upper reaches of the Yellow River and the high turbidity water treatment in the upper reaches of the Yangtze River use secondary sedimentation (clarification) technology, which is suitable for small and medium-sized water plants, sometimes built after the filter tank. Clear water storage pool

Third, preprocessing and advanced processing

In order to further play the overall role of the water treatment process, improve the removal of pollutants, improve and improve the quality of drinking water, in addition to the conventional treatment process, there are pretreatment and advanced treatment processes.

1. According to different ways of removing pollutants, the pretreatment method can be divided into oxidation method and adsorption method, wherein the oxidation method can be further divided into chemical oxidation method and biological oxidation method. The chemical oxidation pretreatment technology mainly includes pretreatment of cl2 and oxidation, ultraviolet oxidation, ozone oxidation, etc. The biooxidation pretreatment technology mainly adopts the biofilm method, and its form is mainly a submerged biofilter, such as TOC biodegradation. , nitrogen removal, iron and manganese removal, etc. Adsorption pretreatment techniques, such as adsorption with powdered activated carbon, adsorption of clay, and the like.

2. Advanced processing. At present, the widely used advanced treatment technologies mainly include activated carbon adsorption method, ozone oxidation method, ozone activated carbon method, biological activated carbon method, photocatalytic oxidation method, and blow-off method.