[Product Introduction]
The suspended chain aerator, also known as Biolak technology, is a new type of aerator developed by our company after years of effort and drawing on the advantages of various similar products from abroad. It is the core equipment of the advanced pollution control process - the improved A/O process (activated sludge biochemical process). It effectively acts on various parts of the tank, providing uniform oxygen supply, high oxygen utilization rate, and low energy consumption. The difference between the suspended chain aerator and other aeration technologies is that the air distribution pipeline floats on the water surface, and the rubber membrane tube aeration unit is connected to the floating air distribution pipeline through a suspended hose. During the aeration process, the rubber membrane tube aeration unit can freely swing underwater, with significant characteristics of high efficiency, low consumption, and easy maintenance. The oxygenation efficiency and power efficiency of the equipment are improved compared to ordinary microporous aeration equipment, and maintenance is simple. It can be repaired and damaged aerators can be replaced without affecting normal operation (without stopping water or gas supply), which is practical and reliable.

Characteristics of using suspended chain mobile aerator process
Save engineering investment
The core structure of the aerator in the hanging chain technology can adopt a joint soil tank structure (phosphorus removal tank, aeration tank, sedimentation tank, secondary aeration tank, and stabilization tank can be freely combined), or existing ponds and natural water systems can be utilized, and the tank shape can be designed into irregular shapes according to the actual situation. The cost of civil engineering has been significantly reduced, and the project investment can be saved by about 30% -50%.
According to different geological conditions and usage requirements, the method of using soil pools can include clay compaction, stone slope protection, and laying HDPE anti-seepage film. After welding and laying the HDPE anti-seepage layer on site, a pressure test is conducted to ensure quality. The anti-seepage effect and service life of HDPE anti-seepage film are higher than those of concrete, while the cost is lower than that of concrete, thereby reducing project investment and shortening construction period.
Save operating costs
Compared to other activated sludge processes, the suspended chain aeration system has significant energy-saving and consumption reducing characteristics: traditional processes have an air-water ratio of around 10:1 under the premise of an aerobic stage residence time of 8 hours, while the suspended chain aeration system can achieve an air-water ratio of 6:1 under the premise of an aerobic stage residence time of 12 hours, greatly reducing power consumption and saving operating costs.
There are two reasons:
One reason is that the bubbles generated by the suspended chain aerator stay in the water for a long time, avoiding the phenomenon of regional unsaturation and supersaturation in traditional fixed aeration devices. Therefore, the oxygen utilization rate is high and the theoretical power efficiency is high.
The second reason is that the mobile aeration method causes a wave distribution of dissolved oxygen concentration in the aeration tank, resulting in the unstable state of beneficial bacterial communities in the water. The impact on biological treatment systems under non steady state conditions is mainly attributed to the influence on microorganisms in the system, including microbial activity, adaptability to the external environment, and the formation of microorganisms with special functions. Unstable conditions can stimulate microorganisms to increase their activity, greatly enhancing their processing capacity.
Easy maintenance and repair
All fasteners of the suspended chain mobile aeration system are located on the water surface, making it easy to maintain. Without stopping the air or emptying the structure, the aerator can be directly lifted out of the water surface for maintenance and repair.
Wide applicability
Suitable for the treatment of newly built urban sewage treatment plants and industrial wastewater from industries such as petrochemicals, textiles, papermaking, printing and dyeing, brewing, pharmaceuticals, and leather making.

Characteristics of Suspension Chain Aerator
The suspended chain mobile aerator adopts EPDM or silicone membrane.
2. Strong collision resistance and not easily damaged.
Equipped with a check valve, it completely solves the problem of backflow.
The 4 floating pipes are welded together with UV resistant materials, which completely solves the problem of air leakage and has a long service life.
All 5 are made of corrosion-resistant materials.

Composition of Suspension Chain Aerator System
The hanging chain aerator consists of a gas supply hose, a floating cloth airway, a hanging hose, and a rubber membrane tube aeration unit. The rubber membrane tube aeration unit is the core of the suspended chain aeration system, which sinks underwater by its own weight; The floating cloth tube floats on the water surface, and the gas supply hose is connected to the gas supply main pipe through a valve. Compressed air is introduced into the floating cloth tube, and then the air is introduced into the rubber membrane tube aeration unit through a hanging hose. The air is released in the form of small bubbles through the micropores on the rubber membrane tube to complete the aeration process. Several sets of rubber membrane tube aeration units are installed on a floating gas pipe, forming an aeration chain that spans both sides of the aeration tank. Multiple chains can be installed in one aeration tank as needed.
Technical advantages:
1. This aerator has a long service life, which can reach 5-8 years, solving the problem of short service life of similar equipment.
2. All materials are made of corrosion-resistant materials with strong collision resistance and are not easily damaged. They can prevent the deposition of large particles of sediment and remove some organic matter. During aeration, the aerator swings left and right, which can remove the sediment at the bottom of the tank and avoid dead zones.
3. High oxygen utilization efficiency, power efficiency, large service area, and low energy consumption. If the air volume needs to be increased or decreased during aeration, the aerator can also be adjusted without affecting normal operation.
4. Installation and maintenance, no need to drain water, no need for any configuration in the tank, and can be directly replaced with this hanging chain aerator without draining water under the condition that the original air intake pipeline used for aeration remains unchanged.

Installation of Suspension Chain Aeration System
The two ends of the floating gas pipe are fixed on both sides of the aeration tank with stainless steel wire ropes; Insert the two ends of the gas supply hose into the gas supply main pipe and the floating cloth pipe respectively, and lock them with pipe clamps; Insert the two ends of the suspension hose into the floating cloth tube joint and the rubber membrane tube aerator joint respectively, and lock them with pipe clamps; As the water level in the aeration tank increases, gradually tighten the stainless steel wire ropes fixed at both ends of the floating aeration tube until the water level rises to the design level. Secure the stainless steel wire ropes at both ends and install the suspension chain aeration system.

Material Performance Table
1. The pipes and fittings shall comply with the GB4217-84 and GB9116.1-88 standards,
2. The components of the aerator shall comply with the national urban construction industry standard CJ/T3015.4-1996.
3. The suspended ventilation hose is made of high-strength polyvinyl chloride pipe.
4. The floating pipe is a UV resistant hard wall bendable (PE) pipe.

Main physical and chemical properties of aeration membrane

[Operation and Maintenance]
Remove all debris from the aeration tank before starting operation.
The time interval between the installation of the suspension chain aerator and the trial operation and formal operation should be as short as possible.
Painting, welding, and other construction are prohibited in aerobic tanks that have already installed suspension chain aerators but have not yet been operated, in order to avoid damage to the rubber membrane of the suspension chain aerators.
Check the air switch and inject clean water to submerge the suspension chain aerator by at least 100-200mm. After a short period of gas supply, turn off and cut off the gas source, and check the airtightness of the aerator and air pipe network one by one. If there is a leak in a certain area due to poor sealing, bubbles will appear there.
Check if there is any air leakage at all pipeline interfaces and sealing points.
Under the condition of a standard ventilation rate of 5.0m3/h, check whether the aeration distribution is uniform, and ensure that the ventilation area of each suspension chain aerator is greater than 80%.
Inspection and testing shall be conducted in accordance with the requirements specified in the national industry standards CJ/T3015.1~2-93 and CJ/T3015.4-1996.
If the trial operation inspection is not immediately put into normal operation, the water level should be raised to at least 1 meter to submerge the suspension chain aerator to prevent adverse effects of ultraviolet radiation and possible extreme cold and hot weather temperatures on the rubber membrane.
Considering the evaporation of water in the pool during long intervals, it is necessary to replenish clean water in a timely manner. The hanging chain aerator should be aerated with standard air volume for at least ten minutes every day.
When the temperature is below 0 º C, the water level in the pool is about 1.5-2 meters to prevent the aerator from freezing. The lower the temperature, the higher the water level in the pool.

[Operation]
During normal operation, the dissolved oxygen in water is maintained at an ideal state by adjusting the air flow rate. However, the adjusted air flow rate should be within the allowable range of the aerator. When the air flow rate is high, the head loss of the suspended chain aerator is large and the oxygen transfer rate is small. A smaller air flow rate cannot fully utilize the performance of the suspended chain aerator, and the aeration in the tank may be uneven. Therefore, the ideal adjustment should be carried out within the recommended air flow rate range.
The recommended air flow rate range is 15-30m3/set, and the normal aeration air flow rate range is 25m3/n • h, with a critical flow rate of 40m3/n • h. It should only be used for a short period of time when cleaning is needed, and should not exceed 10 minutes each time.
The water temperature control range is 5 ℃~35 ℃. Technical parameters:
The air entering the suspension chain aerator should be free of oil, dust, and chemical solvents.

[Problems and Countermeasures]
Due to the use of high-performance and high-quality EPDM rubber material for the suspension chain aerator rubber membrane, only a small amount of maintenance is required during normal operation. Periodic inspection of the aeration system, especially the head loss of the suspended chain aerator, will help operators determine whether the aeration system is working in optimal condition.
The following are possible problems and their solutions:
a. Large bubbles appear in a certain area of the aeration tank
1. Leakage of air distribution pipe:
Solution: Drain the water from the problematic area, use a small amount of air to blow and inspect, determine the location of the leakage, and repair it.
2. Damaged rubber membrane of suspension chain aerator:
Solution: Drain the water from the problematic area, use low air volume to inspect the suspension chain aerator, identify the leaking suspension chain aerator, and replace the rubber diaphragm or the entire suspension chain aerator.
b. Uneven bubbles:
1. Insufficient air volume:
Solution: Check if the blower is running normally.
2. The valve on the air pipe is closed or not fully opened:
Solution: Check if the valve is in the open state.
3. Scale formation on rubber diaphragm:
Solution: Check if there is scale on the rubber film, and if so, clean the rubber film; Replace the rubber diaphragm or the entire aerator.
c. Abnormal decrease in dissolved oxygen in water leads to increased head loss in the aeration system
1. Scale formation on rubber diaphragm:
Solution: Check if there is scale on the rubber film, and if so, clean the rubber film; Replace the rubber diaphragm or the entire aerator.
d. The dissolved oxygen levels in the entire aeration tank are inconsistent:
1. Insufficient air volume:
Solution: Check if the blower is running normally; Check if the valve on the air pipe is in the open position.

[Maintenance and upkeep]
1. Operators should regularly check the aeration status of the aeration system. If the aeration system experiences an increase in water head resistance or a change in bubble shape, the aerator needs to clean sediment such as carbonates, iron salts, aluminum salts, and biological sludge. The scaling on the rubber membrane of the aerator will result in a decrease in air output, a decrease in oxygen utilization law of the aeration system, and an increase in water head loss.
Regular drainage cleaning is an ideal maintenance method, and the duration depends on factors such as the nature of the water being treated and the treatment process.
3. During drainage cleaning and maintenance, be careful not to let the sediment on the surface of the rubber film dry and clump, and clean it immediately. The drying and agglomeration of sediment will make cleaning work difficult, thereby affecting the performance of the aerator.
4. Biological sludge can be removed by physical methods, such as cleaning the rubber membrane surface with a brush or rinsing with a high-pressure water gun. When cleaning with a high-pressure water gun, it is important to maintain a distance of approximately 500mm between the nozzle of the gun and the surface of the rubber film to prevent damage to the rubber film.
5. Carbonate and other scaling should be removed by chemical methods. A certain amount of formic acid should be introduced into the aeration system with air, and the proportion of formic acid added depends on the degree of scaling. It is not necessary to empty the water in the aeration tank during cleaning. Generally, it should be cleaned once or twice a year.
When the suspension chain aerator is damaged or deemed unable to meet performance requirements after cleaning and maintenance, the rubber diaphragm or the entire aerator can be replaced using the same method as installation.