Fiberglass rural sewage treatment equipment

Fiberglass rural sewage treatment equipment

Processing technology:

AO stands for Anaerobic Oxyc, also known as Anaerobic Aerobic Process. A (Anacrobic) is the anaerobic stage used for nitrogen and phosphorus removal; O (Oxyc) is an aerobic stage used for removing organic matter from water. In addition to degrading organic pollutants, it also has a certain denitrification and phosphorus removal function. It uses anaerobic hydrolysis technology as a pretreatment for activated sludge, so AO method is an improved activated sludge method.

Process characteristics:

CASS divides the SBR reaction tank into a biological selector, a pre reaction zone (anoxic zone), and a main reaction zone (aerobic zone) along the length of the tank, with a volume ratio of generally 1:5:30 for each zone. The biological selector is set at the front end of CASS, with a volume accounting for about 10% of the total volume, and usually operates under anaerobic or facultative conditions. The biological selector has a good buffering effect on the quality and quantity of incoming water. By mixing with the returning sludge and incoming water, it can accelerate the removal of dissolved organic matter and the hydrolysis of recalcitrant organic matter. At the same time, it can promote the release of phosphorus and denitrification, thereby improving the settling performance of sludge and effectively inhibiting sludge expansion. The pre reaction zone (anoxic zone) can further promote phosphorus release and denitrification, and can also assist biological selectors in regulating water quality and quantity. The main reaction zone (aerobic zone) is the main place for removing organic matter. During operation, the aeration intensity of the main reaction zone is usually controlled to keep the main solution in an aerobic state and complete the degradation of organic matter. However, the interior of the activated sludge is basically in a state of hypoxia, and the transfer of dissolved oxygen to the sludge flocs is limited. The transfer of nitrate nitrogen from the sludge to the main solution is not limited, so that the degradation of organic matter and synchronous nitrification and denitrification occur simultaneously in the main reaction zone. During operation, complete one cycle by following the steps of water intake - aeration, aeration, sedimentation, decanting, and water intake - idle.

The CASS process is simple, cost-effective, and easy to maintain. It has strong adaptability to water quality and quantity, and has good nitrogen and phosphorus removal effects. Its nitrogen and phosphorus removal effect is currently the strongest among the known SBR variant processes, and it is a relatively proven sewage biological treatment process in practice.

Based on the above description of the basic process of biological denitrification and years of experience in denitrification of coking wastewater, we have summarized that the (A/O) biological denitrification process has the following advantages:

(1) High efficiency. This process has a high removal effect on organic matter, ammonia nitrogen, etc. in wastewater. When the total residence time is greater than 54 hours, the effluent after biological denitrification can be treated with coagulation and sedimentation to reduce the COD value to below 100mg/L, and other indicators can also meet the discharge standards, with a total nitrogen removal rate of over 70%.

(2) Simple process, low investment, and low operating costs. This process uses organic matter in wastewater as the carbon source for denitrification, so there is no need to add expensive carbon sources such as methanol. Especially, with the installation of a device for removing fixed ammonia in the ammonia distillation tower, the carbon nitrogen ratio is increased, and the alkalinity generated during denitrification correspondingly reduces the alkali consumption required for nitrification.

(3) The anaerobic denitrification process has a high degradation efficiency for pollutants. The removal rates of COD, BOD5, and SCN - in the anoxic stage are 67%, 38%, and 59%, respectively, while the removal rates of phenol and organic matter are 62% and 36%, respectively. Therefore, denitrification reaction is an economical and energy-saving degradation process.

(4) High volumetric load. Due to the use of enhanced biochemistry in the nitrification stage and high concentration sludge membrane technology in the denitrification stage, the sludge concentration for nitrification and denitrification has been effectively increased. Compared with similar foreign processes, it has a higher volumetric load.

(5) The anaerobic/aerobic process has strong resistance to load shock. When the inflow water quality fluctuates greatly or the concentration of pollutants is high, this process can maintain normal operation, so the operation and management are also very simple. Through the comparison of the above processes, it is not difficult to see that the biological denitrification process itself not only removes nitrogen, but also degrades organic compounds such as phenol, cyanide, COD, etc. Based on the characteristics of water quantity and quality, we recommend using an anaerobic/aerobic (A/O) biological denitrification (internal circulation) process to ensure that the sewage treatment plant not only meets denitrification requirements, but also other indicators meet discharge standards.

(6) Hydraulic retention time (nitrification>6h, denitrification<2h), sludge concentration MLSS (>3000mg/L), sludge age (>30d), N/MLSS loading rate (<0.03), and total nitrogen concentration in the influent (<30mg/L).

Process flow:

Fiberglass rural sewage treatment equipment

MBR membrane bioreactor

1、 MBR system process flow diagram:

2、 Process characteristics:

Adopting mature A/O+MBR+disinfection treatment process route, it has good removal of organic matter in sewage and good denitrification function to meet the requirements of discharge standards;

◙ Has good shock load resistance to adapt to changes in water quality and quantity;

Adopting the sludge pre reflux denitrification process, greatly reducing the amount of sludge generated;

Adopting a new type of filler, it has fast film hanging, long service life, and fast treatment effect;

Fully consider the possibility of secondary pollution and reduce its impact to a low level;

Adopting PLC centralized control and automated operation, it is easy to manage and maintain, improving system reliability and stability.

The system processing facilities are all located below the ground surface, without occupying any surface area, which can be used for greening and is conducive to anti freezing.

3、 Technical parameter table: