What is precision aeration?

What is precision aeration?

1. What is precision aeration?

Precision aeration is the product of the advancement of sewage treatment plants from early extensive manual control methods to modern refined automatic control methods.

The traditional activated sludge method has been used worldwide for hundreds of years. Many authoritative experts at home and abroad have repeatedly proposed and emphasized that it is necessary to deeply explore the century-old activated sludge process to achieve optimal control and efficient operation of the biochemical treatment process.

The primary goal of precision aeration is to ensure the stable operation of the biochemical treatment process and the stable compliance of the effluent, thereby achieving energy saving and consumption reduction of the aeration system and reducing the operating costs of the sewage treatment plant.

Automation and refined management and control of sewage treatment plants have long been advocated internationally. Precision aeration is an effective tool for sewage treatment plants to achieve refined management, which requires the joint efforts of blowers, aeration equipment, and precision aeration systems.

The precision aeration system can realize various complex air supply schemes, such as intermittent aeration, trace aeration, normal aeration, dissolved oxygen distribution control, etc.; it can help sewage treatment plants to achieve fine-tuning of the process, adapt to various processes, and be able to adjust as the process changes; it can also notify the blower master control to adjust the air volume according to the current required aeration volume, prevent abnormal conditions such as surging, and save blower power consumption.

2. Why do we need to achieve precise aeration?

In the biological treatment process of sewage treatment plants, if the aeration volume is insufficient, the process operation will deteriorate and the effluent water quality will exceed the standard; if the aeration volume is too much, it will lead to high energy consumption and increase the operating cost of the sewage treatment plant. Therefore, only by reasonably allocating and accurately adjusting the aeration volume of each area according to actual needs can the efficient and economical operation of the sewage treatment plant be guaranteed.

A good sewage treatment process automatic control system can not only ensure the continuous and stable operation of sewage treatment plant equipment, but also achieve energy saving and consumption reduction, and has received attention and application in process upgrading and transformation. The precise aeration control system is a set of energy-saving technologies that have been developed in recent years to better control aeration.

3. Composition of the precision aeration system

It mainly consists of the following 6 devices: (1) blower, (2) valve, (3) flow meter, (4) aeration disc/tube, (5) DO and other field instruments, (6) precision aeration control cabinet.（7）. Blower

The blower is the air source supply equipment of the precision aeration system. It is responsible for providing compressed air with suitable pressure and flow. It is the key equipment of the entire precision aeration system. Without a stable air source, there will be no stability of the entire system, not to mention controlling the aeration volume of each corridor and maintaining the stability of parameters and processes. Therefore, choosing a blower suitable for the aeration system is the key to realizing a precision aeration system.

4. Ideal precision aeration system

An ideal precision aeration system should take into account the influence of equipment such as valves, flow meters, DO meters, blowers, etc., and be able to adapt to the working characteristics of these equipment. It should be able to have parameter settings for different process loads, and at the same time, it should have control methods and alarm outputs in emergency situations (such as DO meter failure, blower surge and other unfavorable factors)

There are many manufacturers of precision aeration systems on the market, and their controls are also different, but in general, a perfect precision aeration system should have the following characteristics:

（1）. Adaptability:

An ideal precision aeration system should be able to adapt to different water quality requirements and various supporting process equipment. For other equipment (such as blowers), it can adapt well to its control method, such as flow and pressure control mode.

（2）. Independence:

An ideal precision aeration system should have independent control capabilities. You only need to put the system in automatic mode, and the system can operate according to the set process parameters without being disturbed by other factors such as communication disconnection. And in emergency situations, there are alternative control methods and alarm outputs to ensure parameter stability.

（3）. Parameter selectivity:

The parameters of an ideal precision aeration system should be selectable, such as being able to set the control mode (flow control, valve position control, DO control, etc.), control location (remote/local), control parameters, etc.

（4）. Refinement:

An ideal precision aeration system should refine the control range, because different valves and flowmeter curves are different, and the parameters of different valves and flowmeters can be imported into the precision aeration system, even a butterfly valve can achieve better results.