What is a sewage treatment system?
The sewage treatment system is a system that treats water bodies such as domestic sewage and industrial wastewater through a series of physical, chemical, biological and other methods to meet discharge standards or reuse standards. With the continuous improvement of environmental protection requirements, sewage treatment has become the focus of environmental protection work in various countries around the world.
The basic components of the sewage treatment system:
Sewage treatment systems usually consist of the following parts:
Pretreatment unit: including grilles, grit chambers, etc., mainly removes large particle impurities, suspended solids, etc.
Biological treatment unit: Use microorganisms to decompose organic pollutants. Common ones include activated sludge method, biofilm method, etc.
Physical and chemical treatment unit: Including coagulation sedimentation, filtration, air flotation and other methods, mainly removing suspended solids, dissolved pollutants, etc.
Advanced treatment unit: Further remove residual pollutants in sewage. Commonly used methods include adsorption, membrane separation, ozone oxidation, etc.
Sludge treatment unit: Dehydrate and stabilize the sludge generated during the treatment process, and part of the sludge can be utilized as resources.
How do sewage treatment systems work?
The basic principle of the sewage treatment system is to separate, degrade or transform harmful substances in the sewage into harmless substances through physical, chemical and biological interactions, and ultimately achieve water purification. Through the synergistic effect of multiple treatment units, it can not only remove suspended solids, but also decompose organic matter and remove nitrogen, phosphorus and other pollutants to achieve comprehensive treatment of water quality.
What are the commonly used valves in sewage treatment systems?
Valves are indispensable control elements in sewage treatment systems. They are used to control the flow, pressure and direction of water flow. Different working conditions and processing links require different types of valves. Commonly used valve types include:
How to choose an efficient and durable butterfly valve in sewage treatment? What role does the butterfly valve play in the sewage treatment system?
Butterfly valves play a vital role in sewage treatment systems, especially in large-diameter pipelines and situations that require rapid opening and closing. Its main functions include:
1. Flow control
The butterfly valve can control the flow of water by adjusting the opening of the disc, thereby achieving flow control and regulation of the system.
2. Quick opening and closing
The structure of the butterfly valve determines that it can complete the opening or closing action in a short period of time, so it is suitable for use in pipeline systems that require rapid opening and closing.
3. Takes up little space
Due to its compact structure and small volume, butterfly valves occupy less installation space than gate valves, ball valves and other valves, so they are especially suitable for use in sewage treatment systems where space is limited.
4. Sealing performance
The sealing performance of butterfly valves can be optimized through different sealing materials and designs. Especially in the sewage treatment process, good sealing performance is particularly important when facing water quality containing suspended solids.
Why is hard-sealed butterfly valve preferred in sewage treatment?
In sewage treatment systems, hard-sealed butterfly valves are often preferred, especially in some cases where the working conditions require higher requirements. This is because hard-sealed butterfly valves have many advantages in structure and materials and can adapt to special working conditions in the sewage treatment process.
1. More resistant to high temperature and pressure
Hard-sealed butterfly valves use metal seals, which can withstand higher temperatures and pressures, and have better stability and durability under high-temperature and high-pressure conditions.
2. More resistant to wear and corrosion
Since sewage often contains suspended solids, corrosive chemicals, etc., the metal sealing surface of the hard-sealed butterfly valve has strong anti-wear and anti-corrosion capabilities, which can effectively extend the service life of the valve.
3. Longer sealing performance
The sealing surface of the hard-seal butterfly valve has been specially treated to have high wear resistance and corrosion resistance. The sealing performance is more durable and can maintain a good sealing effect during long-term use.
4. Adapt to harsh working conditions
In some harsh working conditions, such as situations where there are a lot of suspended particles in the sewage and it is highly corrosive, hard-sealed butterfly valves can work more reliably and are less prone to problems such as seal failure.
What are the characteristics and advantages of hard seal butterfly valve?
The reason why hard-sealed butterfly valves are widely used in sewage treatment systems is mainly due to their unique structural characteristics and advantages.
1. The material is hard and durable
The sealing surface of hard-seal butterfly valves is usually made of stainless steel, carbide and other materials, which have high hardness and wear resistance and are not easily worn during long-term use.
2. Strong adaptability to high temperature and high pressure working conditions
Compared with soft-sealed butterfly valves, hard-sealed butterfly valves are more adaptable in high-temperature and high-pressure environments and can maintain stable operation under harsh working conditions.
3. Excellent sealing performance
Although the sealing performance of hard-sealed butterfly valves is not as good as that of soft-sealed butterfly valves, through optimized design and precision machining, hard-sealed butterfly valves can still provide good sealing performance, especially under harsh working conditions in sewage treatment systems, and can still ensure the sealing of the valve. sex.
4. Strong corrosion resistance
Since sewage often contains corrosive substances, the metal sealing surface of the hard-sealed butterfly valve has good corrosion resistance and can operate stably for a long time in a sewage environment containing chemicals such as acids, alkalis, and salts.
5. Long life and low maintenance
Hard-sealed butterfly valves are made of durable materials and strong structures, which generally have a long service life and require less maintenance, greatly reducing the operating costs of the system.
The difference between hard seal butterfly valve and soft seal butterfly valve
Hard-sealed butterfly valves and soft-sealed butterfly valves are two common types of butterfly valves. They have obvious differences in sealing materials and applicable working conditions.
1. Sealing materials
Hard seal butterfly valve: Using metal materials (such as stainless steel, carbide) as the sealing material, it has high wear resistance and corrosion resistance.
Soft sealing butterfly valve: Using elastic materials (such as rubber, PTFE) as sealing materials, the sealing performance is better, but the high temperature resistance and corrosion resistance are poor.
2. Operating temperature range
Hard seal butterfly valve: suitable for high temperature environments and can withstand higher temperatures (usually above 200°C).
Soft sealing butterfly valve: usually only suitable for low temperature environments, with the maximum operating temperature around 150°C.
3. Applicable pressure range
Hard seal butterfly valve: suitable for high-pressure working conditions and able to withstand large working pressure.
Soft sealing butterfly valve: only suitable for medium and low pressure environments.
4. Service life
Hard seal butterfly valve: Because the sealing surface is metal, it has a long service life, especially in abrasive media.
Soft seal butterfly valve: Since the sealing material is elastomer, it is easily damaged in corrosive and abrasive media and has a relatively short service life.
What problems will hard seal butterfly valves encounter during use? How to solve it?
During the use of hard-sealed butterfly valves in sewage treatment systems, you may encounter some common problems. Understanding these problems and mastering the corresponding solutions can effectively improve the operating efficiency and reliability of the system.
1. Seal failure
Since sewage contains particulate matter, corrosive chemicals, etc., the sealing surface of the hard-sealed butterfly valve may be worn or corroded, resulting in sealing failure.
Solution: Check the valve sealing surface regularly and repair or replace it promptly if wear or corrosion is found. Choosing sealing materials with better wear resistance and corrosion resistance is also an effective preventive measure.
2. Inflexible operation
During long-term use, the operation of the hard-sealed butterfly valve may become inflexible, especially when the sewage contains impurities, which may jam the rotating part of the valve.
Solution: Clean the valve regularly, especially the bearing area, to prevent the accumulation of impurities causing operational difficulties. Lubricant can be used if necessary.
3. Corrosion problem
Chemicals contained in sewage may cause corrosion to the metal parts of the valve, especially in strong acid and alkali environments.
Solution: Choose materials with stronger corrosion resistance, such as stainless steel, alloys, etc. At the same time, check the corrosion of valves regularly and perform timely maintenance and repairs.
How to maintain hard seal butterfly valve?
In order to ensure the long-term and stable operation of the hard-sealed butterfly valve in the sewage treatment system, regular maintenance is essential. Here are some common maintenance methods:
1. Check the sealing surface regularly
Regularly check the sealing surface of the hard-seal butterfly valve for wear, corrosion, etc. to ensure that its sealing performance is good. If problems are found, repair or replace them promptly.
2. Clean valves regularly
In sewage treatment, valves are easily blocked by suspended solids, impurities, etc. Therefore, valves should be cleaned regularly, especially key parts such as bearings and sealing surfaces to ensure normal operation of the valve.
3. Lubrication and maintenance
For hard-sealed butterfly valves that operate frequently, lubricants should be regularly used to lubricate the rotating parts of the valve to prevent inflexible operation.
4. Anti-corrosion treatment
Regularly carry out anti-corrosion treatment on the outside of the valve, especially during sewage treatment, the outside of the valve is also susceptible to corrosion by chemical substances. The use of anti-corrosion coatings can effectively extend the service life of valves.
