CN201406344Y - A biological fixed bed reactor - Google Patents

Abstract

The utility model discloses a biological fixed bed reactor, the bottom of the reactor body is provided with a water distribution channel, which communicates with the water inlet pipe; Spherical filter materials with a specific gravity less than 1 of the microbial film are arranged and stacked together to form; the upper part of the filter material layer is covered with a filter plate to prevent the loss of the filter material, and several filter heads for water outlet are arranged on the filter plate; A water outlet is arranged on the wall of the reactor body; an aeration pipe is arranged under the filter material layer inside the reactor body. It occupies a small area, does not produce odor pollution, and has stable sewage treatment performance. It can be used not only for secondary treatment of sewage, but also for advanced treatment of sewage that requires reuse of effluent and other requirements, and can meet high discharge water quality standards.

Description

A biological fixed bed reactor

technical field

The utility model relates to a sewage treatment device, in particular to a biological fixed bed reactor, which is used for treating pollutants such as COD and N in sewage.

Background technique

At present, in the field of sewage treatment, the activated sludge method is undoubtedly a sewage biological treatment technology that is widely used and has good results. However, as the scale of the city continues to expand, it occupies a huge area and the population continues to expand, making the city crowded. In many cities, land is scarce, and the construction of a sewage treatment plant using the activated sludge method often needs to occupy several hectares, or even dozens of hectares. Too large forms a contradiction with urban development, thereby restricting its development.

In addition, the harsh environment and huge sewage treatment structures are exposed to the air in a large area, which easily produces odor pollution, which is unbearable for the surrounding residents. Therefore, more and more residents refuse to be adjacent to the sewage treatment plant.

In addition, the performance of activated sludge treatment of sewage is unstable. Since activated sludge is a kind of suspended microbial micelles, its concentration is usually below 6000 mg/L, and the external environment (such as temperature, pollutant concentration, etc.) The treatment effect will be affected, and even cause sludge bulking, which will deteriorate the treated water quality.

Utility model content

In order to overcome the above-mentioned shortcomings of the prior art, the purpose of this utility model is to provide a biological fixed bed reactor, which occupies a small area, does not produce odor pollution, and has stable sewage treatment performance.

The technical scheme of the utility model is: the biological fixed bed reactor, the bottom of the reactor body is provided with a water distribution channel, which is connected with the water inlet pipe; the reactor body is provided with a filter material layer, and the filter material layer is composed of several surfaces attached with microbial films Spherical filter materials whose specific gravity is less than 1 are arranged and stacked together to form; the upper part of the filter material layer is covered with a filter plate to prevent the loss of filter material, and several filter heads for water outlet are arranged on the filter plate; the reactor above the filter plate A water outlet is arranged on the wall of the main body; an aeration pipe is arranged under the filter material layer in the main body of the reactor.

As a further technical solution of the utility model:

In the biological fixed bed reactor, the thickness of the filter material layer is 3-3.5m.

In the biological fixed bed reactor, the bottom of the reactor body is also connected with a recoil inlet pipe, and the recoil inlet pipe is located below the aeration pipe.

The beneficial effects of the utility model are:

1. Since the filter and the biochemical reactor are combined, the sedimentation tank is no longer needed;

2. It occupies a small area, which is 1/4 to 1/5 of the conventional process, saving a lot of land acquisition and foundation treatment costs;

3. The pool volume is small, and the amount of civil engineering is 20% to 40% less than other processes;

4. All modular structure, easy to rebuild and expand, short construction period;

5. The upper part of the water is clear water, the filter head is not easy to block, and it is easy to repair and replace. No need to empty the filter material in the filter;

6. The factory area can be completely closed, no odor pollution, good visual and landscape effects;

3. There is no need for separate backwashing water and backwashing water pumps, which reduces equipment investment and operating costs;

7. Perforated tube aeration, saving equipment investment and maintenance costs, high efficiency. Membrane aerators, on the other hand, usually begin to lose their efficiency after two years of operation;

9. High degree of automation, few operators; stable operation at low temperature, little affected by temperature;

10. Due to its continuous physical filtration capacity, once a problem occurs in the biological reaction, the filter can still remove most of the suspended solids; and it only takes a few days to restore the biological treatment capacity, while the activated sludge method takes several weeks to recover;

11. The process operation is flexible, and the functions of nitrification and denitrification can be completed simultaneously in the same filter tank.

It can be used not only for secondary treatment of sewage, but also for advanced treatment of sewage that requires reuse of effluent and other requirements, and can meet high discharge water quality standards.

Description of drawings

Below in conjunction with accompanying drawing and embodiment the utility model is described further:

Fig. 1 is the structural representation of the utility model,

In the figure: 1 filter material layer, 2 aeration pipe, 3 reactor body, 4 filter plate, 41 filter head, 5 distribution channel, 6 recoil inlet pipe, 7 water outlet.

Detailed ways

As shown in FIG. 1 , the biological fixed bed reactor is the same as the prior art in that the bottom of the reactor body 3 is also provided with a water distribution channel 5 for communicating with the water inlet pipe. The difference is that the reactor body 3 is provided with a filter material layer 1, and the thickness of the filter material layer is 3-3.5m. The filter material layer 1 is formed by arranging and stacking several spherical filter materials with a microbial film attached to the surface and a specific gravity less than 1. The filter material has a large specific surface area, a high purification capacity, and a high processing load; and it has good mechanical properties and physical and chemical properties, and is not easy to wear. The loss of the filter material is very small, and it is almost unnecessary to replace it. The raw materials of the filter material come from domestic industrial raw materials, which can be produced and processed locally with low cost.

The top of the filter material layer 1 is covered with a filter plate 4 to prevent the loss of the filter material, and several filter heads 41 for water outlet are arranged on the filter plate 4 . Because these filter heads only come into contact with treated water, clogging is avoided; at the same time, because there is no filter material on these filter heads, they are easy to maintain.

A water outlet 7 is provided on the wall of the reactor body above the filter plate 4 for the treated effluent to flow out. The reactor body is provided with an aeration pipe 2 below the filter material layer. Its aeration pipe 2 divides the interior of the reactor body into a lower anaerobic zone and an upper aerobic zone, which can remove all degradable pollutants, carbon-containing pollutants (COD and BOD), suspended solids (SS), ammonia nitrogen and Nitrate (i.e. total nitrogen).

The bottom of the reactor body is also connected with a recoil inlet pipe 6 , and the recoil inlet pipe 6 is located below the aeration pipe 2 .

During work, the water from primary treatment or secondary treatment is evenly distributed to the water inlets of each biological fixed bed reactor through the water distribution weir, and then flows into the water distribution channel 5 at the bottom of the biological fixed bed reactor through the gravity of the water inlet pipe, and the sewage Through the water distribution channel at the bottom of the biological fixed bed reactor, it enters the whole reactor body, and the reactor body realizes uniform water distribution on the entire cross section. The water flows through the filter material attached with microorganisms, and under the action of the oxygen provided by the bottom aeration pipe 2, the carbon-containing pollutants (COD and BOD) in the sewage are degraded, and the ammonia nitrogen is oxidized into nitro nitrogen. Due to the huge and abundant biofilm attached to the filter material, the treatment capacity of the biological fixed bed reactor is much higher than that of the activated sludge method. In addition, the direction of sewage flowing through the filter material layer is the direction of compressing the filter material, rather than the direction of expanding the filter material, which also strengthens the retention of suspended matter, thus eliminating the need for sedimentation tanks.

In the case of nitrification/denitrification, the treated effluent needs to be refluxed. The reflux water and raw water are mixed in the inlet channel and then continue to enter the reactor body. The sewage first enters the anaerobic zone at the lower part of the reactor body, where the reaction is carried out. Nitrification reaction removes nitro nitrogen in the reflux water; then enters the upper aerobic zone, where carbon-containing pollutants are decomposed and ammonia nitrogen is converted into nitro nitrogen.

For the usual nitrification reaction only required (requirements for ammonia nitrogen), a common pipe is used for aeration and recoil intake, so that the entire filter bed is in an aerobic state and most of the degradable pollutants are removed, including Carbon pollutants (COD and BOD), suspended solids (SS) and ammonia nitrogen.

The backwashing water of the reactor utilizes a certain height of clear water layer stored above the filter plate, which can be realized without a backwashing water pump. When backwashing, stop the water into the reactor (an automatic valve can be installed on the water inlet pipe or canal to stop the water inflow), and use the gravity of the clear water layer to flow down through the filter material layer in the opposite direction to the normal filtration, The downward flushing of water can flush the entrapped matter out of the filter material layer in the shortest route, and is the direction in which the entrapped matter falls by gravity, which saves energy and has high efficiency. Periodic reverse flow backwashing removes excess biofilm and entrapped suspended solids. In the process of backwashing, air backwashing can be combined, air backwashing and water backwashing can be carried out alternately, and finally only water backwashing can be performed. After flushing, it can be drained through the distribution channel.

According to different pollutants removed, the biological fixed bed reactor of the present invention can be divided into carbon removal type, nitrification type, nitrification/denitrification type and post-denitrification type.

If a plurality of reactors of the utility model work together, the aeration pipe and recoil air intake pipe of each reactor are all supplied by the same blower, and the blower does not stop working. It's just that in the nitrification/denitrification type reactors, their gas distribution pipe networks are separated and switched by valves. In the single nitrification filter, the process air and the recoil intake are in the same gas distribution pipe network, and the gas supply of the two methods is regulated by the regulating valve at the reactor inlet.

Claims (3)

1. A biological fixed bed reactor, the bottom of the reactor body is provided with a water distribution channel, which communicates with the water inlet pipe. It is characterized in that: the reactor body is provided with a filter material layer, and the filter material layer is composed of several surfaces with microbial film attached. Spherical filter materials with a specific gravity less than 1 are arranged and stacked together to form; the upper part of the filter material layer is covered with a filter plate to prevent the loss of filter material, and several filter heads for water outlet are arranged on the filter plate; the reactor body above the filter plate A water outlet is arranged on the wall; an aeration pipe is arranged under the filter material layer inside the reactor body. 2. A biological fixed bed reactor according to claim 1, characterized in that: the thickness of the filter material layer is 3-3.5m. 3. A biological fixed bed reactor according to claim 1 or 2, characterized in that: the bottom of the reactor body is also connected with a recoil inlet pipe, and the recoil inlet pipe is located below the aeration pipe.

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