CN108083438B

CN108083438B - Downward flow BAF and MBBR double-membrane nitrification biological filter

Info

Publication number: CN108083438B
Application number: CN201810077999.8A
Authority: CN
Inventors: 蒋富海; 曲艳慧; 袁安江; 安鹏; 董德风; 吕丹丹; 崔丹红
Original assignee: Csd Water Service Co ltd
Current assignee: Csd Water Service Co ltd
Priority date: 2018-01-26
Filing date: 2018-01-26
Publication date: 2021-05-25
Anticipated expiration: 2038-01-26
Also published as: CN108083438A

Abstract

The invention provides a downward flow BAF and MBBR double-membrane nitrification biological filter, which comprises: a water inlet device and a water distribution channel which are positioned at the upper part of the biological filter; the MBBR light filler layer is positioned at the middle upper part of the biological filter; a granular filter material layer positioned below the MBBR light filler layer; an aeration layer, a filter plate and a filter head layer, a backwashing device layer and a water collecting area positioned at the bottom of the biological filter are sequentially arranged from top to bottom below the granular filter material layer; wherein the water outlet area of the biological filter is vertically arranged along the outer wall of the biological filter body, and a water passing hole is arranged between the water outlet area and the water collecting area.

Description

Downward flow BAF and MBBR double-membrane nitrification biological filter

Technical Field

The invention relates to the field of sewage treatment, in particular to a downward flow BAF and MBBR double-membrane nitrification biofilter.

Background

Most of the existing BAF (Biological Aerated Filter) filters adopt a single Filter material, the reaction retention time is short, the biomass intercepted or attached on the Biological Filter material is less, and backwashing operation and the like can often cause elutriation and loss of Biological sludge on the Filter material. And because DO (Dissolved Oxygen) instruments are not convenient to install in the filter tank, DO in the filter tank cannot be monitored and adjusted, operating efficiency such as decarbonization, nitrification and denitrification is poor due to the lack of biomembrane regulation means, and functions such as organic matter carbonization (C), nitrification (N) and Denitrification (DN) cannot be realized in a single tank.

At present, BAF filter tanks are basically divided into a nitrification filter tank (N) and a denitrification filter tank (DN), wherein a ceramsite single filter material is mostly adopted for nitrification, the biomass attached to a biological membrane is limited, and the pollutant removal effect is poor. As the nitrification filter tank is internally filled with a thicker ceramsite filter material layer, a DO instrument is not convenient to install, the energy consumption management of the running of the fan is relatively extensive, and an effective detection and diagnosis means is lacked for the running of the unit regulation DO.

Disclosure of Invention

In order to solve or alleviate the problems in the prior art, the invention provides a downward flow BAF and MBBR double-membrane nitrification biological filter.

According to one aspect of the invention, a down-flow BAF and MBBR double membrane nitrification biofilter is provided, the biofilter comprising: a water inlet device and a water distribution channel which are positioned at the upper part of the biological filter; the MBBR light filler layer is positioned at the middle upper part of the biological filter; a granular filter material layer positioned below the MBBR light filler layer; the aeration device, the filter plate and the filter head layer, the backwashing device layer and the water collecting area are sequentially arranged below the granular filter material layer from top to bottom; the water outlet area of the biological filter is vertically arranged along the outer wall of the biological filter body in a rectangular shaft mode, and water passing holes are formed between the water outlet area and the water collecting area.

Preferably, in the biofilter according to the present disclosure, a vertical sleeve for placing the monitoring instrument may be provided on an inner side wall of the biofilter, a lower end of the sleeve vertically extending up to a position adjacent to the aeration device, and a lower end portion of the sleeve being closed. Further preferably, the upper end of the sleeve is higher than the top of the biological filter.

In one embodiment of the biofilter according to the invention, the walls of the sleeves are provided with water inlet holes arranged vertically at different depths. Preferably, the water inlet of the sleeve is an inlet of a probe tube arranged on the sleeve.

In one embodiment of the biofilter according to the invention, a monitoring instrument is disposed in the sleeve at a position movable in the sleeve, preferably the monitoring instrument is a dissolved oxygen detector.

Preferably, in the biofilter according to the present invention, a ceramsite filter material may be laid in the granular filter material layer.

Preferably, in the biofilter according to the present invention, the backwashing means comprises water washing means and/or gas washing means.

Further preferably, in the biofilter according to the present invention, the dissolved oxygen detector is interlocked with the aeration apparatus.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention, as claimed.

Drawings

Further objects, features and advantages of the present invention will become apparent from the following description of embodiments of the invention, with reference to the accompanying drawings, in which:

FIG. 1 is a schematic configuration diagram of one embodiment of a biological filter according to the present invention;

FIG. 2 is a schematic view showing the structure of the casing and the monitoring apparatus in the biofilter according to the present invention.

Detailed Description

The objects and functions of the present invention and methods for accomplishing the same will be apparent by reference to the exemplary embodiments. However, the present invention is not limited to the exemplary embodiments disclosed below; it can be implemented in different forms. The nature of the description is merely to assist those skilled in the relevant art in a comprehensive understanding of the specific details of the invention.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In the drawings, the same reference numerals denote the same or similar parts, or the same or similar steps.

In order to solve or relieve the problems of limited attached biomass, poor pollutant removal effect and the like of the prior BAF filter tank, the invention provides a downward flow BAF and MBBR (Moving Bed Biofilm Reactor) double-membrane nitrification biofilter,

according to one aspect of the present invention, there is provided a down-flow BAF and MBBR double membrane nitrification biofilter (hereinafter simply referred to as biofilter), comprising: a water inlet device and a water distribution channel which are positioned at the upper part of the biological filter; the MBBR light filler layer is positioned at the middle upper part of the biological filter; a granular filter material layer positioned below the MBBR light filler layer; the aeration device, the filter plate and the filter head layer, the backwashing device layer and the water collecting area are sequentially arranged below the granular filter material layer from top to bottom; wherein the water outlet area of the biological filter is vertically arranged along the outer wall of the biological filter body, and a water passing hole is arranged between the water outlet area and the water collecting area.

In a preferred embodiment of the biofilter according to the invention, the inside side walls of the biofilter may be provided with vertical sleeves for receiving monitoring instruments, the lower ends of the sleeves extending vertically up to a position adjacent to the aeration means. Further preferably, the upper end of the sleeve is higher than the top of the biological filter. The wall of the sleeve can be provided with water inlet holes which are vertically arranged and are positioned at different depths. Preferably, the water inlet hole of the sleeve is an inlet of a probe tube vertically arranged on the sleeve.

Preferably, the lower end of the sleeve is closed at the bottom end, so that water can only enter the water inlet holes with different depths.

In one embodiment of the biofilter according to the present invention, a monitoring instrument is disposed in the sleeve and can move in position in the sleeve, and preferably, the monitoring instrument is a dissolved oxygen detector. Preferably, in the biofilter according to the present invention, a ceramsite filter material may be laid in the granular filter material layer.

For example, in the example of the filter according to an embodiment of the present invention shown in fig. 1, the upper portion of the biological filter communicates with a water inlet device 10 and a distribution channel 8; the middle upper part of the filter body is provided with MBBR light filler 6, and a granular filter material layer 5 is arranged below the MBBR light filler, and is a ceramsite filter material in the example. An aeration device and a filter plate 4 are arranged below the ceramsite filter material, a filter head 41 is arranged on the filter plate 4, and a water collecting area 1 is arranged below the filter plate.

The upper part of the water outlet area 2 is communicated with a water outlet pipeline 11.

Preferably, the backwashing device in the biological filter comprises a water washing device 14 communicated with the water collecting area 1, a gas washing device 13 arranged below the water collecting area and the filter plate, a backwashing water drainage channel 9 communicated with the upper part of the filter, and a backwashing water drainage device 15 communicated with the backwashing water drainage channel.

Preferably, a filler interception grille 7 is arranged at the communication part of the backwashing drainage channel 7 and the filter body.

Preferably, the aeration device is arranged between the ceramsite filter material layer 5 and the filter plate 4, and the aeration device further comprises an aeration fan arranged outside the filter body.

Preferably, the water inlet device 10, the aeration device 12, the water outlet pipeline, the water washing device 14, the air washing device 12 and the backwashing water discharging device 15 can be provided with valves on the pipelines.

The monitoring instrument in the present invention may be a portable DO detector (dissolved oxygen detector) placed inside the vertical sleeve (outer protective sleeve) 17 described above. For example, the sleeve 17 can be said to be mounted on the inner side wall of the filter body through the fixing bracket 20. In the embodiment shown in the drawings, the movable DO probe is arranged with its bottom near the filter plate and preferably with its upper part above the top of the filter body, and can be lifted to different heights inside the casing 17.

Preferably, the sleeve 17 is provided with probe tubes 18 at different depths, the probe tubes being provided with openings. Preferably, a filter screen 19 for intercepting the filter material may be provided at the opening of the probe tube.

Preferably, the probe tube 19 is provided with two openings symmetrically at the same horizontal level.

Preferably, the DO detection device is interlocked with the aeration device.

In the embodiment, the biological filler is added and is layered and symbiotic with the existing ceramsite filter material, so that a mixing double-membrane system of the light filler and the ceramsite filter material is realized, the specific surface area of a carrier for biological growth is increased, the biological activity and biomass are greatly improved, and the biological filler has the capability of resisting water inflow impact load such as organic matters, ammonia nitrogen, TN and SS. Another aspect of the present invention provides a configuration capable of conveniently mounting a monitoring instrument. For example, by installing a movable DO detection device, DO levels of different depths of a filter material layer of the BAF filter tank can be conveniently known under the aeration/micro-aeration state, so that the operation frequency of a fan is conveniently controlled, the DO environment (anoxic, facultative and aerobic) suitable for a filter material layer biomembrane is ensured, carbonization, nitrification and denitrification are realized, and the energy conservation and consumption reduction of an aeration fan can be realized to a certain extent.

An example of one embodiment according to the present invention is specifically described below with reference to the accompanying drawings.

FIG. 1 is a schematic view of the combined structure of a downward flow BAF and MBBR double-membrane nitrification biological filter in the invention. The biological filter tank is used for water feeding and distribution through a top channel and comprises a filter tank body, wherein the upper part of the filter tank body is communicated with a water feeding device 10 and a water distribution channel 8. The middle part of the filter body is filled with MBBR light filler 6 and ceramsite filter 5. The aeration device 12 and the filter plate 4 are arranged below the ceramsite filter material 5, the filter head 41 is arranged on the filter plate 4, and the water collecting area 1 is arranged below the filter plate 4. The biological filter is also provided with a water outlet area 2 communicated with the water collecting area 1 through the overflowing hole 3, and the water outlet area 2 is communicated with a water outlet pipeline 11. The aeration device 12 is arranged between the ceramsite filter material 5 and the filter plate 4, and the aeration device 12 can also comprise an aeration fan and the like which are arranged outside the filter body. A filter material bearing layer can be arranged below the ceramsite filter material 5 and is used for bearing the filter material. According to the downward flow BAF and MBBR double-membrane nitrification biological filter, the MBBR light filler with a certain proportion is added into the filter body to serve as a carrier for strengthening biological growth, so that the biomass is greatly improved, the number and activity of dominant organisms are improved, the reaction residence time of a system is prolonged, and the functions of removing pollutants such as ammonia nitrogen, denitrification and the like are strengthened on the basis of the conventional ceramsite filter material.

According to one aspect of the invention, the water outlet zone 1 can be vertically arranged along the outer wall of the filter body, and the water outlet pipeline 11 is communicated with the upper part of the water outlet zone 2. The water outlet pipeline 11 may be provided with a valve, which may be an electric valve or a pneumatic valve, etc.

According to another aspect of the invention, the biological filter is also provided with a backwashing device and the like, comprising a water washing device 14, a gas washing device 13, a backwashing water drainage channel 9, a backwashing water drainage device 15 and the like. The water washing device 14 may communicate with one side of the sump 1. The gas washing device 13 may be arranged in the water collection area 1. The outer side of the filter body can be provided with an air blower, an air inlet pipeline and the like. And air distribution pipelines and the like can be distributed in the filter body and below the filter plate 4. The backwashing water draining channel 9 is communicated with the upper part of the filter body, and the backwashing water draining device 15 is communicated with the backwashing water draining channel 9, so that the backwashing wastewater is convenient to discharge. Preferably, a filler interception grid 7 is arranged at the communication part of the backwashing drainage channel 9 and the filter body, so that the phenomenon of material leakage of MBBR fillers in the gas/water backwashing stage is prevented.

Further preferably, the water inlet device 10, the aeration device 12, the water outlet pipeline 11, the water washing device 14, the air washing device 13, and the backwashing water discharging device 15 are all provided with valves, and the valves can be electric valves, pneumatic valves, and the like. The biological filter tank with the above mode meets the functions of biodegradation, filtration and removal through water inlet and outlet, and realizes the shedding of the aged biological membrane of the ceramsite filter material and the MBBR light filler through air washing, air-water combined washing and water washing, thereby improving the sludge activity on the biological membrane carrier.

In the example shown in fig. 1 and fig. 2, the monitoring instrument is arranged along the inner side wall of the filter body, and the detection position along the water depth direction can be moved according to the requirement, so that the water depth state states in the filter can be monitored. In this example, the monitoring apparatus comprises an outer protective sleeve 17 and a DO detection device 16 (which may be in-line, the DO probe is connected using a flexible signal cable, the length of which may be up to the aeration device; or may be portable) disposed within the outer protective sleeve 17 for measuring the dissolved oxygen content. Wherein the bottom of the outer protective sleeve 17 is close to the filter plate, and the upper part of the outer protective sleeve is higher than the top of the filter body. The DO meter can be raised or lowered to different heights within the outer protective sleeve.

The outer protective sleeve 17 is provided with probe tubes 18 at different depths, the probe tubes 18 are provided with openings, and the openings are provided with filter screens 19 for intercepting the filter material 5 or the filler 6 so as to protect probes of the DO instrument 16 from being damaged by collision. For example, the probe tube 18 has two openings symmetrically arranged at the same horizontal height, so that oxygenated water in different water depths in the filter tank can enter the outer protective sleeve 17 through the probe tube 18. Through the DO instrument 16 arranged in the outer protective sleeve 17, the DO instrument 16 can be lifted to different heights, and DO concentration in different water depths can be measured.

Preferably, other devices in the biological filter and the movable DO detection device are synchronously interlocked and controlled through the DO instrument 16 and the aeration device 12 in the biological filter, so that different DO environments of the inner surface and the outer surface of the filter material layer and the filler layer are realized, and the functions of deep decarbonization, nitrification removal of pollutants such as ammonia nitrogen and denitrification are synchronously realized.

In the embodiment, the MBBR filler is combined with the BAF filter, and the deep enhanced removal of carbon and nitrogen and the efficient interception of SS (Suspended Solid) are realized through a filler and filter material double-membrane sludge system. The filler and the filter material are subjected to a regular air-water automatic backwashing program to complete the sludge demoulding and updating on the biological membrane.

By installing the movable DO detection device, DO detection is carried out on different water depths in the tank, the aeration device of the filter tank system is interlocked and controlled in time, different facultative and aerobic reaction environments inside and outside the biological membrane are realized, synchronous nitrification and denitrification of the inner layer and the outer layer of the biological membrane are realized to a certain extent, and energy conservation and consumption reduction of the aeration device can also be realized synchronously.

According to the downward flow BAF and MBBR biological filter, the beneficial effects can be obtained at least in that:

1. the MBBR light filler is added into the filter tank main body in a certain proportion and is used as a carrier for strengthening the growth of organisms, the biomass is greatly improved, the number and activity of dominant organisms are improved, the reaction residence time of a system is prolonged, and the functions of removing pollutants such as ammonia nitrogen, denitrification and the like are strengthened on the basis of the existing ceramsite filter material.

2. Through installing movable monitoring instrument, for example DO detection device, survey different water depths in the pond, in time interlock regulation and control the equipment such as aeration equipment of filtering pond system, realize the different facultative, good oxygen reaction environment of biofilm inside and outside, realize the synchronous nitrification and denitrification of biofilm inside and outside layer to a certain extent, the energy saving and consumption reduction that aeration equipment also can be realized to the synchronization.

Other embodiments of the invention will be apparent to those skilled in the art from consideration of the specification and practice of the invention disclosed herein. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the invention being indicated by the following claims.

Claims

1. A down-flow BAF and MBBR double-membrane nitrification biological filter, which is characterized by comprising:

a water inlet device and a water distribution channel which are positioned at the upper part of the biological filter;

the MBBR light filler layer is positioned at the middle upper part of the biological filter;

a granular filter material layer positioned below the MBBR light filler layer;

the aeration device, the filter plate and the filter head layer, the backwashing device layer and the water collecting area are sequentially arranged below the granular filter material layer from top to bottom;

the water outlet area of the biological filter is vertically arranged along the outer wall of the biological filter body in a rectangular shaft mode, and water passing holes are formed between the water outlet area and the water collecting area; a vertical sleeve for placing a monitoring instrument is arranged on the side wall of the inner side of the biological filter, the lower end of the sleeve vertically extends to a position adjacent to the aeration device, and the lower end part of the sleeve is closed;

a monitoring instrument capable of moving in the sleeve is placed in the sleeve, the sleeve is provided with probe tubes at different depths, the probe tubes are symmetrically arranged at the same horizontal height, and an opening of each probe tube is provided with a filter screen for intercepting filter materials;

the monitoring instrument is a dissolved oxygen detector;

the dissolved oxygen detector and the aeration device are controlled in an interlocking way.

2. A biofilter according to claim 1, wherein the upper end of said sleeve is higher than the roof of said biofilter.

3. A biofilter according to claim 1, wherein a ceramsite filter material is laid in said granular filter material layer.

4. A biofilter according to claim 3, wherein said backwashing means comprises water washing means and/or gas washing means.

5. A biofilter according to claim 3, wherein said backwashing means comprises water washing means communicating with the water collection region, gas washing means disposed below the water collection region and the filter plate, backwashing water discharge channels communicating with an upper portion of the filter, backwashing water discharge means communicating with the backwashing water discharge channels.