Water treatment mode

Water treatment development process

In ancient times, people at that time did not have advanced water treatment technology, in order to reduce the water transmission of diseases, they used simple grid interception and natural settlement methods for water treatment. Subsequently, after years of observation and summary, they also found a way to filter out fine suspended matter with sand, and then appeared the chemical coagulation pretreatment. With the continuous progress of human civilization, the waste generated by human beings and the destruction of the environment have led to serious pollution of water resources. When various infectious diseases spread through water, causing many people to become sick or die, people discovered how important water treatment is. It is for this reason that people gradually began to study water treatment technology.

Since the end of the 19th century, industrial technology has been greatly developed, and industrial sewage is also doubled year by year. At that time, the rivers and lakes of the industrial powers were also seriously polluted and gradually became social hazards. Typical examples include the near-death of fish in the Thames in the United Kingdom, the death of a large number of organisms in the Mississippi River in the United States, and the pollution of Minamata Bay in Kumamoto Prefecture, Japan, by methylmercury, resulting in bone pain in nearby residents. People found that simple chemical and physical methods and difficult to treat these sewage, the research of new water treatment technology has been impatient. Scientists in various countries have begun to study water treatment methods, the earliest is the sewage aeration test, and then the biofilm method, and then the artificial biological treatment method, and now the targeted ion exchange method, electrochemical method and other high-tech.

In the 1990s, with the idea of sustainable development, many countries began to use systems engineering methods. Taking economic development and environmental protection into account, water treatment is not only to treat the sewage that has taken shape, but to control it from the source. Due to the rapid economic development in recent decades, people found that the traditional water treatment process has been difficult to meet the needs of the society, so they began to apply biotechnology to the water supply process. Not only that, with the generation of water resources crisis, the process of sewage reuse has also become a point of concern. In order to improve water quality and improve the current environment, land irrigation, oxidation pond and other sewage treatment technologies based on ecological principles have also been developed.

Treatment process:

Sewage treatment generally includes the following three levels of treatment: primary treatment is it through mechanical treatment, such as grille, precipitation or air flotation, remove the stone, sand and fat, iron ions, manganese ions, grease and so on contained in sewage. Secondary treatment is biological treatment, where pollutants in sewage are degraded and converted into sludge under the action of microorganisms. Tertiary treatment is the advanced treatment of sewage, which includes the removal of nutrients and the disinfection of sewage by chlorination, ultraviolet radiation or ozone technology. Depending on the target of the treatment and the quality of the water, some sewage treatment processes do not include all of the above processes.

Pure water treatment process, depending on the quality of raw water.

If the raw water is municipal tap water, the general process is

Sand filter - activated carbon filter - softening (optional) - security filter - reverse osmosis - UV disinfection - water production

If it is general surface water, sterilize and add flocculant before entering the above process.

If it is well water, iron and manganese filters should be added after sand filtration.

Water is recycled for purification.

Quartz sand filtration is one of the most effective means to remove suspended matter in water, and it is an important unit in sewage advanced treatment, sewage reuse and water supply treatment. Its role is to further remove the pollutants that have been flocculated in the water, and it achieves the purpose of water purification through the interception, sedimentation and adsorption of the filter material.

two Scope of application

1. For industrial water, domestic water and municipal water supply systems requiring effluent turbidity ≤5mg/L to meet drinking water quality standards;

2. Removal of suspended matter and solid matter in industrial sewage;

3. It can be used as pretreatment equipment in ion exchange softening and desalt system, and crude filtration equipment for industrial water supply with low water quality requirements;

And used in swimming pool circulation treatment system, cooling circulation water purification system, etc.

Pollutant discharge standard editor broadcast

GB18918-2002 is the "urban sewage treatment plant pollutant discharge standard", while GB8978-1996 is the "sewage comprehensive discharge standard", the two are different concepts, both have their own targets, the two can not be mixed.