1. technical name

Full-process energy saving and consumption reduction precise operation control technology.

2. scope of application

Sewage treatment plant and station upgrading, capacity expansion, efficiency improvement and low-carbon operation management.

3. technical content

3.1 technical principle

(1) Multi-parameter control technology for precise sand removal and mud discharge. The air-water ratio, sand suction time and the optimal volume of the sand-water separator are determined based on parameters such as inlet water volume, sand content, sand suction pipe displacement and particle size distribution, so as to form a feed-forward real-time control of high-efficiency sand sedimentation, intelligent sand lifting, and precise sand separation. Control sand removal technology; combined with the changing characteristics of sludge concentration in the primary sedimentation tank, real-time sludge monitoring methods are used to form a sludge time-series sludge discharge control technology to stabilize the sludge concentration and total amount discharged from the primary sedimentation tank. (2) Precise control technology based on models and big data analysis. Developed technologies such as precise aeration control based on load balancing-pressure adjustment-dissolved oxygen regulation based on gas demand prediction, precise phosphorus removal control based on adaptive adjustment of biological/chemical coupling effects, and real-time precise sludge age control based on sludge material balance; and established a precise aeration model, a phosphorus removal dosing model and a dynamic sludge age control model, using big data analysis to achieve adaptive adjustment control. (3) Real-time control technology for full-process multi-factor systems. A quantitative indicator system such as target quantities, operating quantities and related quantities for multi-factor operating units such as desanding, aeration, denitrification, phosphorus removal, primary sedimentation/residual sludge discharge has been established. Through order issuance, execution of operations, and feedback improvement, real-time dynamic control of the entire process is realized.

3.2 main innovations

(1) The first systematic control technology based on model and big data analysis has filled the gap in precise sand removal and precise mud age control, broken through the bottleneck of the engineering application of full-process precision control technology, and solved the problem of online process stability in corrosive environments. Control problems, achieve precise control in dynamic processes and significant energy conservation and consumption reduction, and significantly reduce the number of people on duty. (2) In response to outstanding problems such as severe fluctuations in the influent water quality and quantity of sewage treatment plants, complex and changeable treatment processes, and difficulty in ensuring the stability and reliability of instruments in corrosive environments, an adaptive precise control method based on model and big data analysis has been proposed., a multi-factor control model based on target quantities, operating quantities and related quantities has been established, and an efficient and intelligent sand removal system for sand removal, sand removal and sand separation, a triple precise aeration control system, and a precise phosphorus removal system have been developed. The real-time precise mud age control system and the multi-factor real-time dynamic control system achieve precise control of the entire process. The sludge concentration discharged from the primary sedimentation tank is stably controlled within the set value ±300mg/L, the dissolved oxygen is controlled within the set value ± 0.2 mg/L, and the sludge age is controlled within the set value ±12%.

4. Pollution control or environmental restoration effects

Intelligent and precise control during the operation of the sewage treatment plant has been achieved, and power consumption, drug consumption and carbon emissions have been reduced by 10% to 40%. Taking the original site standard raising project of Gaobeidian Sewage Treatment Plant, the first million-ton sewage treatment plant in China, as an example, under the condition that the retention time of the biochemical water is shortened by 1/3 compared with the conventional process, the biological denitrification and phosphorus removal efficiency after the technical transformation is significantly improved, and the total nitrogen in the secondary effluent is reduced by more than 50%.

5. Technology demonstration

This technology has been applied in 11 reclaimed water plants with a total scale of 4.13 million m3/d in the central Urban area of Beijing, and has been radiated to standard improvement and efficiency improvement projects in sewage treatment plants in Xiongan, Nanning and other places. It was first applied to the standard raising and renovation project of Gaobeidian Sewage Treatment Plant, the first million-ton sewage treatment plant in China, achieving the original site raising of Gaobeidian Sewage Treatment Plant without additional land occupation. The retention time of biological pond water is shortened by 1/3 compared with conventional processes, the expansion of influent pollutant load exceeds the design value by 25%, the total nitrogen in secondary effluent is reduced by more than 53%, and the deep effluent index stably reaches the "quasi-IV" standard of GB3838 -2002. The sand production volume has increased by 2.8 times, and the mass of fine gravel with a particle size of ≤ 0.2 mm accounts for 6.8%, and the removal amount has increased by 160 times; the electricity consumption for aeration per ton of water is 0.09 kW·h, which is reduced by 38%. The dosing rate of phosphorus removal agents has been reduced by 30%, and the additional carbon source has been reduced by 87%. In the past three years, electricity bills and medical expenses have been saved hundreds of millions of yuan. Compared with conventional processes, it saves hundreds of millions of yuan in project costs, and plays a role in demonstrating the transformation of national sewage treatment plants and stations to improve standards and increase efficiency from traditional to precise.

6. investment estimation

Taking a 100,000 m3/d sewage treatment plant as an example, the investment in the precise phosphorus removal control system is 1.2 million yuan, the investment in the precise nitrogen removal system is 1.2 million yuan, the investment in the precise aeration control system is 2.8 million yuan, and the investment in the precise sludge discharge control system is 1 million yuan. The investment in the precise sludge age control system is 1 million yuan.

7. investment recovery period

The payback period for the precision phosphorus removal system, precision nitrogen removal system and precision aeration system is about 3 years.

8. Prospects for transformation and promotion of technological achievements

At present, my country is operating more than 5000 sewage treatment plants with a treatment capacity of nearly 200 million m3/d. After this technology is promoted nationwide, it can save 3.2 billion kilowatt-hours of electricity, 3.87 million tons of additional carbon source (sodium acetate), and 3.63 million tons of phosphorus removal agents every year, save 7.5 billion yuan in operating costs, and have good economic and social environmental benefits.