CN111196629A - Drop oxygenation control system for upflow denitrification biological filter - Google Patents
Drop oxygenation control system for upflow denitrification biological filter Download PDFInfo
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- CN111196629A CN111196629A CN202010160057.3A CN202010160057A CN111196629A CN 111196629 A CN111196629 A CN 111196629A CN 202010160057 A CN202010160057 A CN 202010160057A CN 111196629 A CN111196629 A CN 111196629A
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- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F3/00—Biological treatment of water, waste water, or sewage
- C02F3/28—Anaerobic digestion processes
- C02F3/2826—Anaerobic digestion processes using anaerobic filters
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- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2209/00—Controlling or monitoring parameters in water treatment
- C02F2209/005—Processes using a programmable logic controller [PLC]
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- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
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Abstract
The invention discloses a drop oxygenation control system for an upflow denitrification biological filter, which is used for thoroughly solving the problems that the drop oxygenation of a water distribution channel of the denitrification biological filter seriously inhibits denitrification and limits the denitrification capability of the system in the prior art; the problem that the running cost is additionally increased sharply due to the fact that the dissolved oxygen in the inlet water is too high and a large amount of additional denitrification carbon source is wasted because of drop oxygenation of the denitrification biological filter is thoroughly solved; effectively reducing the problem of overlarge backwashing water quantity of the existing biological filter, ensuring the economical stability of the effluent to reach the standard, having stronger impact resistance and having great popularization and application values.
Description
Technical Field
The invention relates to a sewage treatment process, in particular to a drop oxygenation control system for an upflow denitrification biological filter.
Background
At present, with the increasingly prominent water pollution problem in China, the improvement of the discharge standard of urban sewage treatment tends to be great, and the biomembrane sewage treatment technology is widely researched and applied, wherein the aeration biofilter is widely applied to the field of sewage deep treatment due to the advantages of small occupied area, low operation cost, small capital investment, high treatment load, convenient operation and management, good treatment effect and the like. In the process, the upflow denitrification biological filter has good denitrification effect especially on nitrogen in sewage. At present, a plurality of processes for advanced denitrification treatment of sewage exist, wherein the advanced denitrification treatment technology of the denitrification biofilter shows better development prospect and market value, but the prior art still has more problems which are mainly shown as follows.
The denitrification biological filter is used for sewage deep denitrification treatment, a channel and pipeline mode is adopted for water distribution, during channel water distribution, the phenomenon of aeration along with drop is very serious, and the dissolved oxygen of inlet water of the denitrification biological filter is too high, the defect exists that ① denitrification bacteria belong to heterotrophic anaerobic bacteria, the heterotrophic anaerobic bacteria need to grow and propagate under the anoxic/anaerobic condition, the high-concentration dissolved oxygen can seriously inhibit denitrification (the dissolved oxygen in a biological membrane system is controlled to be less than 1.0 mg/L), the denitrification capability of the system is seriously limited, 0.733kgO2 needs to be provided when 1kgBOD is removed by ②, a large amount of additional denitrification carbon source is wasted when the dissolved oxygen of the inlet water of the denitrification biological filter is too high, for example, a sewage treatment plant with the treatment scale of 50 ten thousand tons per day, the aeration of the inlet water of the denitrification biological filter is increased by 4-6 mg/L, the cost of carbon source (sodium acetate) in one year is increased by nearly 600-800 ten thousand yuan due to the problem of drop dissolved oxygen, the large amount of the aerobic heterotrophic bacteria in the sewage treatment process is increased, and the backwash resistance of the aerobic heterotrophic bacteria is increased, so that the filter bed is frequently shortened.
Therefore, it is necessary to develop a deep denitrification control system which aims at controlling the concentration of dissolved oxygen in the inlet water of the denitrification biological filter, uniformly distributing water and stably making the sewage reach the standard economically and stably.
Disclosure of Invention
The invention aims to solve the problems and provide a control system for drop oxygenation of an upflow denitrification biological filter to overcome the problems encountered at present. The specific contents are as follows: the upward flow denitrification biological filter consists of a transverse water passage, a water distribution channel, a liquid level meter, an electric water distribution valve, a water distribution chamber, a long-handle filter head, a filter plate, a support layer, a filter material reaction layer, a clear water area, a backwashing water drainage channel, a water outlet pipeline, a backwashing water system, a backwashing gas system and a PLC system; the transverse water channel is connected with a water distribution channel of the upflow denitrification biological filter to control even water inflow of the plurality of groups of upflow denitrification biological filters; the liquid level meter in the water distribution channel is respectively connected with the water distribution electric valve and the PLC system and is used for measuring, feeding back, adjusting and controlling and feeding back the drop head; the control system process of drop oxygenation of the upflow denitrification biological filter is as follows:
(1) drop head measurement and parameter setting: the difference value of the liquid level meter in the water distribution channel and the opening degree signal of the water distribution electric valve are led to the PLC system; the liquid level meter is used for measuring the liquid level difference between the weir water head of the transverse water passing channel and the water surface in the water distribution channel, namely the drop level difference of the liquid level meter, and the value of the drop level difference is 0.1-0.3 m;
(2) constantly adjusting drop head: 1) after backwashing is finished, the aged biomembrane and suspended matters intercepted by the filter material layer are backwashed out of the filter by a backwashing system, so that the head loss of the filter material layer in the upflow denitrification biomembrane filter is reduced to the minimum (resistance is minimum), the drop head difference between the weir head of a transverse water channel and the water surface of a water distribution channel is maximum, the opening degree of a water distribution electric valve is reduced through a PLC (programmable logic controller) system, the head loss of the water distribution electric valve is reduced, the constant water level is maintained, the phenomena of drop oxygenation and air entrainment oxygenation are prevented, and uniform water distribution is synchronously realized; 2) along with the prolonging of the time after the backwashing, the biomembrane of the upflow denitrification biofilter continuously grows, the increase of the amount of the intercepted suspended matter is increased, the opening degree of the water distribution electric valve is increased through a PLC system, the head loss is reduced, the constant water level is kept, the head loss of the water distribution electric valve is reduced, the dynamic control of the constant water level is realized, the phenomena of drop oxygenation and air entrainment oxygenation are prevented, and the uniform water distribution is synchronously realized; 3) during backwashing, the opening degree of a water distribution electric valve of the upward flow denitrification biological filter is 0, and the water distribution electric valve is in a closed state.
The opening degree of the water distribution electric valve is 0-100%, and the opening degree of the water distribution electric valve is dynamically controlled through a drop head value monitored by a PLC.
The upward flow denitrification biological filter is composed of a water distribution chamber, a bearing layer, a filter material reaction layer, a clear water area, a water outlet channel and a water outlet pipeline from bottom to top in sequence, wherein a long-handle filter head and a filter plate are arranged in the water distribution chamber, and the bearing layer and the filter material reaction layer are arranged on the long-handle filter head and the filter plate.
The adjustable electric valve of the normal water inlet pipeline is provided with three controls of opening, stopping and closing, can display the specific opening percentage of the valve and can upload a PLC system.
The filter material can be a ceramsite filter material, a quartz stone filter material, a volcanic rock filter material and a shale filter material.
The thickness of the filter material reaction layer is 1.8-4.0 m.
The transverse water passing channel can uniformly distribute water for at least 2 groups of water distribution channels.
The invention thoroughly solves the problems that the drop oxygenation of the water distribution channel of the denitrification biological filter seriously inhibits the denitrification effect and limits the denitrification capability of the system in the current situation; the problem that the running cost is additionally increased sharply due to the fact that the dissolved oxygen in the inlet water is too high and a large amount of additional denitrification carbon source is wasted because of drop oxygenation of the denitrification biological filter is thoroughly solved; effectively reducing the problem of overlarge backwashing water quantity of the existing biological filter, ensuring the economical stability of the effluent to reach the standard, having stronger impact resistance and having great popularization and application values.
Drawings
FIG. 1 is a schematic structural diagram of a drop oxygenation control system for an upflow denitrification biological filter according to the invention.
Wherein: 1. the device comprises an upward flow denitrification biological filter, 2, a transverse water passage, 3, a water distribution channel, 4, a liquid level meter, 5, a normal water inlet pipeline, 6, an electric water distribution valve, 7, a water distribution chamber, 8, a supporting layer, 9, a filter material reaction layer, 10, a clean water area, 11, a backwashing water discharge channel, 12, a water outlet channel, 13, a long-handle filter head, 14, a filter plate, 15, a water outlet pipeline, 16, a backwashing water system, 17, a backwashing gas system, 18, a control cable, 19 and a PLC system.
Detailed Description
The invention is further illustrated with reference to figure 1:
a control system for drop oxygenation of an upflow denitrification biofilter (1), characterized in that: the upward flow denitrification biological filter (1) is composed of a transverse water passage (2), a water distribution channel (3), a liquid level meter (4), an electric water distribution valve (6), a water distribution chamber (7), a long-handle filter head (13), a filter plate (14), a support layer (8), a filter material reaction layer (9), a clear water area (10), a backwashing drainage channel (11), a water outlet channel (12), a water outlet pipeline (15), a backwashing water system (16), a backwashing gas system (17) and a PLC system (19); the transverse water channel (2) is connected with a water distribution channel (3) of the upflow denitrification biological filter (1) to control even water inflow of the plurality of groups of upflow denitrification biological filters (1); the liquid level meter (4) in the water distribution channel (3) is respectively connected with the water distribution electric valve (6) and the PLC system (19) and is used for measuring, feeding back, adjusting and controlling and feeding back the drop head; the control system process of drop oxygenation of the upflow denitrification biological filter (1) is as follows:
(1) drop head measurement and parameter setting: the difference value of the liquid level meter (4) in the water distribution channel (3) and the opening degree signal of the water distribution electric valve (6) are led to a PLC system (19); the liquid level meter (4) is used for measuring the liquid level difference between the weir water head of the transverse water passing channel (2) and the water surface in the water distribution channel (3), namely the drop level difference of the liquid level meter (4), and the value of the drop level difference is 0.1-0.3 m;
(2) constantly adjusting drop head: 1) after backwashing is finished, the aged biomembrane and suspended matters intercepted by the filter material layer are backwashed out of the filter by a backwashing system, so that the head loss of the filter material layer (9) in the upflow denitrification biological filter (1) is reduced to the minimum (resistance is minimum), the head difference between the weir head of a transverse water channel (2) and the water surface of a water distribution channel (3) is maximum, the opening degree of an electric water distribution valve (6) is reduced by a PLC (programmable logic controller) system (19), the head loss of the electric water distribution valve (6) is increased, the constant water level is maintained, the phenomena of drop oxygenation and gas entrainment oxygenation are prevented, and uniform water distribution is synchronously realized; 2) along with the prolonging of the time after the backwashing, the biomembrane of the upflow denitrification biofilter (1) continuously grows, the amount of the intercepted suspended matter is increased, the opening degree of the water distribution electric valve (6) is increased through the PLC system (19), the head loss is reduced, the constant water level is maintained, the head loss of the water distribution electric valve (6) is increased, the dynamic control of the constant water level is realized, the phenomena of drop oxygenation and aeration oxygenation are prevented, and the uniform water distribution is synchronously realized; 3) during backwashing, the opening degree of a water distribution electric valve (6) of the upward flow denitrification biological filter (1) is 0, and the valve is in a closed state.
The opening degree of the water distribution electric valve (6) is 0-100%, and the opening degree of the water distribution electric valve (6) is dynamically controlled through a drop head value number monitored by a PLC;
upward flow denitrification biological filter (1) from up constitute (15) by distributing water room (7), supporting layer (8), filter material reaction layer (9), clear water district (10), outlet canal (12), outlet conduit in proper order down, install long handle filter head (13), filter plate (14) in distributing water room (7), be supporting layer (8) and filter material reaction layer (9) on it.
The adjustable electric valve (6) of the normal water inlet pipeline (5) is provided with three controls of opening, stopping and closing, can display the specific opening percentage of the valve and can upload a PLC system (19).
The filter material can be a ceramsite filter material, a quartz stone filter material, a volcanic rock filter material and a shale filter material.
The thickness of the filter material reaction layer is 1.8-4.0 m.
The transverse water passing channel (2) can uniformly distribute water for at least 2 groups of water distribution channels (3).
Example 1:
the treatment flow of a certain municipal sewage treatment plant in Hebei province is 40000m3/d, the prokaryotic core process is an oxidation ditch and secondary sedimentation tank process, a denitrification biofilter is adopted for upgrading and removing TN, the outlet water of the secondary sedimentation tank is lifted to a denitrification water distribution channel for the second time by a lifting pump, the DO value of the water distribution channel is 1.0mg/L, the DO value of the water distribution channel falling into a single denitrification water inlet pipe is 8mg/L, after the drop oxygenation control system is adopted, the DO value of the water distribution channel falling into the single denitrification water inlet pipe is reduced to 0.9mg/L, the waste of carbon sources caused by drop oxygenation is basically avoided, and the operation cost is greatly saved.
Example 2:
the treatment flow of a sewage treatment plant in a certain chemical industry park in Jiangsu province is 20000m3/d, the original main process is 'hydrolysis acidification + AAO + secondary sedimentation tank' process, secondary treatment effluent enters a denitrification biological filter tank process for TN index upgrading, secondary sedimentation tank effluent enters a denitrification biological filter tank water distribution channel, the DO value of the water distribution channel is 1.5mg/L, the DO value of the water distribution channel falling into a single denitrification water inlet pipe is 7.9mg/L, after the drop oxygenation control system is adopted, the DO value of the water distribution channel falling into the single denitrification water inlet pipe is reduced to 0.5mg/L, waste of carbon sources caused by drop oxygenation is basically avoided, and the cost of carbon sources is saved by 60 ten thousand yuan per year.
The invention thoroughly solves the problems that the drop oxygenation of the water distribution channel of the denitrification biological filter seriously inhibits the denitrification effect and limits the denitrification capability of the system in the current situation; the problem that the running cost is additionally increased sharply due to the fact that the dissolved oxygen in the inlet water is too high and a large amount of additional denitrification carbon source is wasted because of drop oxygenation of the denitrification biological filter is thoroughly solved; effectively reducing the problem of overlarge backwashing water quantity of the existing biological filter, ensuring the economical stability of the effluent to reach the standard, having stronger impact resistance and having great popularization and application values.
The above-mentioned embodiments are merely illustrative of the technical ideas and features of the present invention, and the purpose thereof is to enable those skilled in the art to understand the contents of the present invention and implement the present invention, and not to limit the protection scope of the present invention. All equivalent changes and modifications made according to the spirit of the present invention should be covered within the protection scope of the present invention.
Claims (7)
1. A control system for drop oxygenation of an upflow denitrification biological filter is characterized in that: the upward flow denitrification biological filter consists of a transverse water passage, a water distribution channel, a liquid level meter, an electric water distribution valve, a water distribution chamber, a long-handle filter head, a filter plate, a support layer, a filter material reaction layer, a clear water area, a backwashing water drainage channel, a water outlet pipeline, a backwashing water system, a backwashing gas system and a PLC system; the transverse water channel is connected with a water distribution channel of the upflow denitrification biological filter to control even water inflow of the plurality of groups of upflow denitrification biological filters; the liquid level meter in the water distribution channel is respectively connected with the water distribution electric valve and the PLC system and is used for measuring, feeding back, adjusting and controlling and feeding back the drop head; the control system process of drop oxygenation of the upflow denitrification biological filter is as follows:
(1) drop head measurement and parameter setting: the difference value of the liquid level meter in the water distribution channel and the opening degree signal of the water distribution electric valve are led to the PLC system; the liquid level meter is used for measuring the liquid level difference between the weir water head of the transverse water passing channel and the water surface in the water distribution channel, namely the drop level difference of the liquid level meter, and the value of the drop level difference is 0.1-0.3 m;
(2) constantly adjusting drop head: 1) after backwashing is finished, the aged biomembrane and suspended matters intercepted by the filter material layer are backwashed out of the filter by a backwashing system, so that the head loss of the filter material layer in the upflow denitrification biomembrane filter is reduced to the minimum (resistance is minimum), the drop head difference between the weir head of a transverse water channel and the water surface of a water distribution channel is maximum, the opening degree of a water distribution electric valve is reduced by a PLC system, the head loss of the water distribution electric valve is increased, the constant water level is maintained, the phenomena of drop oxygenation and air entrainment oxygenation are prevented, and uniform water distribution is synchronously realized; 2) along with the prolonging of the time after the backwashing, the biomembrane of the upflow denitrification biofilter continuously grows, the increase of the amount of the intercepted suspended matter is increased, the opening degree of the water distribution electric valve is increased through a PLC system, the head loss is reduced, the constant water level is kept, the head loss of the water distribution electric valve is reduced, the dynamic control of the constant water level is realized, the phenomena of drop oxygenation and air entrainment oxygenation are prevented, and the uniform water distribution is synchronously realized; 3) during backwashing, the opening degree of a water distribution electric valve of the upward flow denitrification biological filter is 0, and the water distribution electric valve is in a closed state.
2. The system for controlling drop oxygenation in an upflow denitrification biofilter according to claim 1, wherein: the opening degree of the water distribution electric valve is 0-100%, and the opening degree of the water distribution electric valve is dynamically controlled through a drop head value monitored by a PLC.
3. The system for controlling drop oxygenation in an upflow denitrification biofilter according to claim 1, wherein: the upward flow denitrification biological filter is composed of a water distribution chamber, a bearing layer, a filter material reaction layer, a clear water area, a water outlet channel and a water outlet pipeline from bottom to top in sequence, wherein a long-handle filter head and a filter plate are arranged in the water distribution chamber, and the bearing layer and the filter material reaction layer are arranged on the long-handle filter head and the filter plate.
4. The system for controlling drop oxygenation in an upflow denitrification biofilter according to claim 1, wherein: the adjustable electric valve of the normal water inlet pipeline is provided with three controls of opening, stopping and closing, can display the specific opening percentage of the valve and can upload the opening percentage to the PLC system.
5. The system for controlling drop oxygenation in an upflow denitrification biofilter according to claim 1, wherein: the filter material can be a ceramsite filter material, a quartz stone filter material, a volcanic rock filter material and a shale filter material.
6. The system for controlling drop oxygenation in an upflow denitrification biofilter according to claim 1, wherein: the thickness of the filter material reaction layer is 1.8-4.0 m.
7. The system for controlling drop oxygenation in an upflow denitrification biofilter according to claim 1, wherein: the transverse water passing channel can uniformly distribute water for at least 2 groups of water distribution channels.
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| CN202010160057.3A CN111196629A (en) | 2020-03-10 | 2020-03-10 | Drop oxygenation control system for upflow denitrification biological filter |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111718068A (en) * | 2020-06-28 | 2020-09-29 | 安徽华骐环保科技股份有限公司 | Water distribution method for solving drop oxygenation of denitrification biological filter |
| CN112225310A (en) * | 2020-09-28 | 2021-01-15 | 中国市政工程华北设计研究总院有限公司 | Water-feeding dissolved oxygen full-flow control system and operation control method for denitrification filter |
| CN114455705A (en) * | 2022-04-13 | 2022-05-10 | 北京高能时代环境技术股份有限公司 | HEDN bioreactor and treatment method |
-
2020
- 2020-03-10 CN CN202010160057.3A patent/CN111196629A/en active Pending
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111718068A (en) * | 2020-06-28 | 2020-09-29 | 安徽华骐环保科技股份有限公司 | Water distribution method for solving drop oxygenation of denitrification biological filter |
| CN112225310A (en) * | 2020-09-28 | 2021-01-15 | 中国市政工程华北设计研究总院有限公司 | Water-feeding dissolved oxygen full-flow control system and operation control method for denitrification filter |
| CN114455705A (en) * | 2022-04-13 | 2022-05-10 | 北京高能时代环境技术股份有限公司 | HEDN bioreactor and treatment method |
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