JPH04958Y2 - - Google Patents
Info
- Publication number
- JPH04958Y2 JPH04958Y2 JP1985027121U JP2712185U JPH04958Y2 JP H04958 Y2 JPH04958 Y2 JP H04958Y2 JP 1985027121 U JP1985027121 U JP 1985027121U JP 2712185 U JP2712185 U JP 2712185U JP H04958 Y2 JPH04958 Y2 JP H04958Y2
- Authority
- JP
- Japan
- Prior art keywords
- blower
- pressure
- flow rate
- blowing
- air
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
- 238000007664 blowing Methods 0.000 claims description 38
- 230000007423 decrease Effects 0.000 claims description 14
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 5
- 238000000034 method Methods 0.000 description 4
- 239000010802 sludge Substances 0.000 description 4
- 230000006866 deterioration Effects 0.000 description 3
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 229910052760 oxygen Inorganic materials 0.000 description 2
- 239000001301 oxygen Substances 0.000 description 2
- 239000010865 sewage Substances 0.000 description 2
- 239000002351 wastewater Substances 0.000 description 2
- 230000003247 decreasing effect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000001788 irregular Effects 0.000 description 1
- 238000003908 quality control method Methods 0.000 description 1
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
- Y02W10/00—Technologies for wastewater treatment
- Y02W10/10—Biological treatment of water, waste water, or sewage
Landscapes
- Activated Sludge Processes (AREA)
Description
【考案の詳細な説明】
Ａ 産業上の利用分野
本考案は活性汚泥プロセスなど、ブロワから制
御弁を介して風をとり込んで種々の制御を行う処
理施設に対する送風圧力制御装置に関する。[Detailed Description of the Invention] A. Field of Industrial Application The present invention relates to an air blowing pressure control device for a processing facility, such as an activated sludge process, which takes in air from a blower via a control valve to perform various controls.
Ｂ 考案の概要
活性汚泥プロセスなどの処理施設に対する送風
圧力制御装置において、ブロワ吸込側の総風量を
求め、総風量に基づいて総風量の低下に対し所定
の関係で低下する送風圧力を設定し、ブロワ吐出
側の送風圧力を検出し、ブロワ吸込側制御弁を操
作して上記検出送風圧力を上記設定送風圧力に制
御することにより、処理施設が必要とする風量が
低下する場合でもブロワ吐出側制御弁の開度低下
を防ぎ、これにより圧力損失（エネルギー損失）
の増大を防ぐと共に制御性の悪化、ハンチング現
象が生じるのを防ぐようにしたものである。B. Summary of the idea In a blowing pressure control device for treatment facilities such as activated sludge process, the total air volume on the blower suction side is determined, and based on the total air volume, the blowing pressure is set to decrease in a predetermined relationship with respect to the decrease in total air volume. By detecting the blowing pressure on the blower discharge side and controlling the detected blowing pressure to the set blowing pressure by operating the blower suction side control valve, the blower discharge side can be controlled even when the air volume required by the treatment facility decreases. Prevents the valve opening from decreasing, thereby reducing pressure loss (energy loss)
This is designed to prevent an increase in the amount of noise, as well as to prevent deterioration of controllability and hunting phenomenon.
Ｃ 従来の技術
有機物排水などを処理する活性汚泥プロセスに
おいては、流入負荷変動による処理水質の悪化を
防止するため、種々の水質制御が行われている。C. Prior Art In an activated sludge process for treating organic wastewater, etc., various water quality controls are carried out to prevent deterioration of treated water quality due to fluctuations in inflow load.
このうち送風量の制御も、処理水質の安定化と
省エネルギー化を実現するため、重要なことであ
る。 Among these, controlling the air flow rate is also important in order to stabilize the quality of treated water and save energy.
従来の活性汚泥プロセスにおいては、送風圧力
制御は図面中の、可変送風圧設定装置１が存在せ
ず、設定圧力PSETは固定されていた。即ち、従来
は、独立した複数の処理施設２1〜２ｍへ１ケ所
のブロワ施設３から送風する場合、ブロワ吐出側
制御弁V11〜V14……Vn1からVn4の相互干渉を防
止するため、ブロワ吐出側本幹４の圧力を一定値
に制御していた。なお、図面中で、５は流入汚
水、６はDO（溶存酸素）制御装置、７はDO値設
定器、８1〜８ｍはDO計、９11〜９14及び９n1〜
９n4はブロワ吐出側風量計であり、例えばDO値
が一定となるように、所要の風量を算出して弁開
度が制御される。１０は圧力計、B1〜Bnはブロ
ワ、V1からVnはブロワ吸込側制御弁、１１1〜１
１ｎはブロワ吸込側風量計、１２は総風量算出装
置、１３は偏差アンプ、１４は圧力制御装置、１
５は送風流量設定値配分演算装置、１６は偏差ア
ンプ、１７は流量制御装置である。 In the conventional activated sludge process, the variable blowing pressure setting device 1 shown in the drawing does not exist for blowing pressure control, and the set pressure P SET is fixed. That is, conventionally, when air is blown from one blower facility 3 to a plurality of independent processing facilities 2 1 to 2 m, mutual interference between the blower discharge side control valves V 11 to V 14 ...V n1 to V n4 is prevented. Therefore, the pressure in the main blower discharge side 4 was controlled to a constant value. In the drawing, 5 is inflowing wastewater, 6 is a DO (dissolved oxygen) control device, 7 is a DO value setting device, 8 1 to 8m is a DO meter, 9 11 to 9 14 and 9 n1 to
9 n4 is a blower discharge side air volume meter, and the valve opening degree is controlled by calculating the required air volume so that the DO value is constant, for example. 10 is a pressure gauge, B 1 to Bn are blowers, V 1 to Vn are blower suction side control valves, 11 1 to 1
1n is a blower suction side airflow meter, 12 is a total airflow calculation device, 13 is a deviation amplifier, 14 is a pressure control device, 1
Reference numeral 5 designates an air blowing flow rate set value distribution calculation device, 16 a deviation amplifier, and 17 a flow rate control device.
Ｄ 考案が解決しようとする問題点
ところが、本幹４での圧力が一定の場合、設定
圧力に対し総風量QAが一定のときは問題ないが、
必要な風量が低下してくるにつれてブロワ吐出側
制御弁V11〜V14……Vn1からVn4も全体的に低開
度となつて問題が生じる。即ち、低開度になる
と、この制御弁のところで圧力損失、換言すれば
エネルギー損失が増大する。また、低開度部分で
は開度と風量の関係が急傾斜（敏感）になり、
DO定値制御などを行う場合も制御性が悪化し、
ハンチング現象（不規則動作）が起ることもあ
る。D Problems that the invention aims to solve However, if the pressure in the main trunk 4 is constant, there is no problem when the total air volume Q A is constant for the set pressure, but
As the required air volume decreases, the blower discharge side control valves V 11 to V 14 . . . V n1 to V n4 also have a low opening degree as a whole, causing a problem. That is, when the opening degree becomes low, pressure loss, or in other words, energy loss, increases at this control valve. In addition, the relationship between the opening degree and the air volume becomes steep (sensitive) in the low opening part.
Controllability also deteriorates when performing DO fixed value control, etc.
Hunting phenomenon (irregular movement) may also occur.
本考案は上述した従来技術の問題点に鑑み、必
要な総風量が低下してもブロワ吐出側制御弁が極
端に低開度とならず、常に適正な弁開度になるよ
うにした送風圧力制御装置を提供することを目的
とする。 In view of the problems of the prior art described above, the present invention has been developed to prevent the blower discharge side control valve from opening at an extremely low opening even if the required total air volume decreases, and to maintain the blowing pressure at an appropriate valve opening at all times. The purpose is to provide a control device.
Ｅ 問題点を解決するための手段
上述した目的を達成する本考案の送風圧力制御
装置は、吐出側が共通管に接続された複数のブロ
ワからブロワ吐出側制御弁を介して風をとり込ん
で水質制御が行われている処理施設に対する送風
圧力制御装置において、ブロワ毎にブロワ吸込側
に設けられた風量計と、ブロワ毎にブロワ吸込側
に設けられたブロワ吸込側制御弁と、前記ブロワ
吐出側の共通管に設けられた圧力計と、前記各風
量計の検出値からブロワ吸込側の総風量を算出す
る総風量算出装置と、総風量の低下に対して送風
圧力が低下する予め定めた関係に基づき、前記算
出した総風量に対応する送風圧力を圧力設定値と
する可変送風圧力設定装置と、圧力設定値と前記
圧力計で検出したブロワ吐出側の送風圧力との偏
差を算出する圧力偏差算出装置と、前記算出した
圧力偏差に応じた制御信号を出力する圧力制御装
置と、前記制御信号に基づき圧力偏差をゼロとす
る送風流量を算出すると共に、この送風流量の算
出値を、個々のブロワの容量及び稼働状況に応じ
て個々のブロワの送風流量設定値に配分する送風
流量設定値配分装置と、ブロワ毎に、前記送風流
量設定値と前記風量計の検出値との偏差を算出す
る流量偏差算出装置と、ブロワ毎に、前記算出し
た流量偏差に応じて前記ブロワ吸込側制御弁を制
御する流量制御装置とを備える。E. Means for Solving the Problems The air blowing pressure control device of the present invention, which achieves the above-mentioned purpose, takes in air from a plurality of blowers whose discharge sides are connected to a common pipe through a blower discharge side control valve, and improves water quality. In a blowing pressure control device for a processing facility that is being controlled, an air flow meter provided on the blower suction side for each blower, a blower suction side control valve provided on the blower suction side for each blower, and the blower discharge side A pressure gauge installed in the common pipe of the airflow meter, a total airflow calculation device that calculates the total airflow on the blower suction side from the detected values of each of the airflow meters, and a predetermined relationship in which the blowing pressure decreases as the total airflow decreases. a variable blowing pressure setting device that sets the blowing pressure corresponding to the calculated total air volume as the pressure setting value based on the above, and a pressure deviation that calculates the deviation between the pressure setting value and the blowing pressure on the blower discharge side detected by the pressure gauge. a calculation device; a pressure control device that outputs a control signal according to the calculated pressure deviation; and a pressure control device that calculates a blowing flow rate that makes the pressure deviation zero based on the control signal, and calculates the calculated value of the blowing flow rate to each individual. An air flow rate set value distribution device that allocates the air flow rate set value to each blower according to the capacity and operating status of the blower, and a deviation between the air flow rate set value and the detected value of the air flow meter for each blower is calculated. A flow rate deviation calculation device and a flow rate control device for controlling the blower suction side control valve according to the calculated flow rate deviation for each blower.
Ｆ 作用
設定送風圧力が総風量の低下に応じて所定の関
係で低下することにより、ブロワ吐出側制御弁の
開度は極端に低下せず、常に適正な範囲になる。F Effect: Since the set air blowing pressure decreases in a predetermined relationship as the total air volume decreases, the opening degree of the blower discharge side control valve does not decrease excessively and always remains within an appropriate range.
Ｇ 実施例
図面により本考案の一実施例を説明する。図面
中、１は可変送風圧力設定装置であり、総風量
QAが低下すると設定圧力PSETも所定の関係で低下
するようになつており、この関係がグラフ化ある
いは数式化されている。G. Example An example of the present invention will be described with reference to the drawings. In the drawing, 1 is a variable blowing pressure setting device, which controls the total air volume.
When Q A decreases, the set pressure P SET also decreases according to a predetermined relationship, and this relationship is graphed or expressed mathematically.
各処理施設は２1〜２ｍと複数個存在し、それ
ぞれQ1〜Qmという流量で汚水が流入している。
また各処理施設では、例えばDO定値制御などが
実施されている。この場合、各処理施設によつて
は、DO設定値はそれぞれ独立に設定することが
できる。またDO制御の操作端はブロワ吐出側制
御弁V11〜V14……Vn1からVn4である。この制御
は従来から一般に行われている。 Each treatment facility has a plurality of 2 1 to 2 m in length, and sewage flows into each of them at a flow rate of Q 1 to Qm.
In addition, each treatment facility implements, for example, DO fixed value control. In this case, depending on each treatment facility, the DO setting value can be set independently. Further, the operation ends of the DO control are the blower discharge side control valves V 11 to V 14 . . . V n1 to V n4 . This control has been commonly performed.
本考案では、総風量算出装置１２によりB1〜
Bnのうち運転中のブロワの送風量を加算して総
風量QAを求める。この総風量QAを可変送風圧力
設定装置１に与え、対応する適正な送風圧力設定
値PSETが得られる。圧力設定値PSETが求まると、
これと本幹４の実測した送風圧力PMESとを比較
し、
PMES＝PSET
となるように圧力制御装置１４が送風流量設定値
配分演算装置１５に制御信号を与える。この送風
流量設定値配分演算装置１５はPMES＝PSETに見合
う送風流量を決定すると共に、各ブロワの容量、
ブロワの稼働・非稼働等の条件に基づいて、所要
のブロワに対する流量設定値を個々に定める。す
ると流量制御装置１７が設定した流量値となるよ
うにブロワ吸込側制御弁V1〜Vnのうち運転制御
中のものを制御する。これにより本幹４での送風
圧力が設定圧力になる。 In the present invention, the total air volume calculation device 12 calculates B 1 to
Calculate the total air volume Q A by adding the air volume of the operating blower out of Bn. This total air volume Q A is given to the variable blowing pressure setting device 1, and a corresponding appropriate blowing pressure setting value P SET is obtained. Once the pressure set value P SET is determined,
This is compared with the blowing pressure P MES actually measured by the main trunk 4, and the pressure control device 14 gives a control signal to the blowing flow rate set value distribution calculation device 15 so that P MES = P SET . This air flow rate set value distribution calculation device 15 determines the air flow rate corresponding to P MES = P SET , and also determines the capacity of each blower,
Based on conditions such as whether the blower is in operation or not, the required flow rate setting value for the blower is determined individually. Then, the flow rate control device 17 controls the blower suction side control valves V 1 to Vn that are under operational control so that the set flow rate value is achieved. As a result, the blowing pressure in the main trunk 4 becomes the set pressure.
可変送風圧力設定装置１におけるQAとPSETの関
係は各機場によつて異なるので、予め実験等で求
めておく。例えば、ブロワ吸込側制御弁V1〜Vn
を或る開度に固定しておき、ブロワ吐出側制御弁
V11〜V14……Vn1〜Vn4の開度を何段階かに変化
させ、各段階における本幹４の圧力を測定するこ
とにより、QAとPSETの関係が求まる。 Since the relationship between Q A and P SET in the variable blast pressure setting device 1 differs depending on each pump station, it is determined in advance through experiments or the like. For example, blower suction side control valve V 1 ~Vn
is fixed at a certain opening, and the blower discharge side control valve
The relationship between Q A and P SET is determined by changing the opening degrees of V 11 to V 14 ...V n1 to V n4 in several stages and measuring the pressure in the main trunk 4 at each stage.
なお、上記実施例では処理施設をDO定値制御
としたがこれに限定されるものではない。 In addition, in the above embodiment, the treatment facility is controlled to a fixed DO value, but the present invention is not limited to this.
Ｈ 考案の効果
総風量の低下により送風圧力設定値を適正な低
い値に修正することにより、ブロワ吐出側制御弁
が常に適正な弁開度範囲で制御される。これによ
りブロワ吐出側制御弁が極端な低開度にならず、
圧力損失が増大したり、制御性が悪化することが
ない。H. Effect of the invention By correcting the air blowing pressure set value to an appropriately low value due to a decrease in the total air volume, the blower discharge side control valve is always controlled within an appropriate valve opening degree range. This prevents the blower discharge side control valve from opening at an extremely low opening.
No increase in pressure loss or deterioration of controllability.
図は本考案の一実施例装置のブロツク図であ
る。
図面中、１は可変送風圧力設定装置、２1〜２
ｍは処理施設、３はブロワ施設、４はブロワ吐出
側本幹、５は流入汚水、６はDO（溶存酸素）制
御装置、７はDO値設定器、８1〜８ｍはDO計、
９11〜９14及び９n1〜９n4は風量計、１０は圧力
計、B1〜Bnはブロワ、V1〜Vnはブロワ吸込側
制御弁、１１1〜１１ｎはブロワ吸込側風量計、
１２は総風量算出装置、１３は偏差アンプ、１４
は圧力制御装置、１５は送風流量設定値配分演算
装置、１６は偏差アンプ、１７は流量制御装置で
ある。
The figure is a block diagram of an apparatus according to an embodiment of the present invention. In the drawing, 1 is a variable blowing pressure setting device, 2 1 to 2
m is the treatment facility, 3 is the blower facility, 4 is the main blower discharge side, 5 is the inflowing sewage, 6 is the DO (dissolved oxygen) control device, 7 is the DO value setting device, 8 1 to 8m is the DO meter,
9 11 to 9 14 and 9 n1 to 9 n4 are air flow meters, 10 is a pressure gauge, B 1 to Bn are blowers, V 1 to Vn are blower suction side control valves, 11 1 to 11n are blower suction side air flow meters,
12 is a total air volume calculation device, 13 is a deviation amplifier, 14
1 is a pressure control device, 15 is an air flow rate set value distribution calculation device, 16 is a deviation amplifier, and 17 is a flow rate control device.
Claims (1)
らブロワ吐出側制御弁を介して風をとり込んで
水質制御が行われている処理施設に対する送風
圧力制御装置において、 (b) ブロワ毎にブロワ吸込側に設けられた風量計
と、 (c) ブロワ毎にブロワ吸込側に設けられたブロワ
吸込側制御弁と、 (d) 前記ブロワ吐出側の共通管に設けられた圧力
計と、 (e) 前記各風量計の検出値からブロワ吸込側の総
風量を算出する総風量算出装置と、 (f) 総風量の低下に対して送風圧力が低下する予
め定めた関係に基づき、前記算出した総風量に
対応する送風圧力を圧力設定値とする可変送風
圧力設定装置と、 (g) 圧力設定値と前記圧力計で検出したブロワ吐
出側の送風圧力との偏差を算出する圧力偏差算
出装置と、 (h) 前記算出した圧力偏差に応じた制御信号を出
力する圧力制御装置と、 (i) 前記制御信号に基づき圧力偏差をゼロとする
送風流量を算出すると共に、この送風流量の算
出値を、個々のブロワの容量及び稼働状況に応
じて個々のブロワの送風流量設定値に配分する
送風流量設定値配分装置と、 (j) ブロワ毎に、前記送風流量設定値と前記風量
計の検出値との偏差を算出する流量偏差算出装
置と、 (k) ブロワ毎に、前記算出した流量偏差に応じて
前記ブロワ吸込側制御弁を制御する流量制御装
置と、 を備えたことを特徴とする送風圧力制御装置。[Scope of Claim for Utility Model Registration] (a) Air blowing pressure control device for a treatment facility where water quality is controlled by taking in air from multiple blowers whose discharge sides are connected to a common pipe via a blower discharge side control valve. (b) an air flow meter provided on the blower suction side for each blower, (c) a blower suction side control valve provided on the blower suction side for each blower, and (d) a common pipe on the blower discharge side. (e) a total air volume calculation device that calculates the total air volume on the suction side of the blower from the detected values of each of the air volume meters; (f) a predetermined value for reducing the blowing pressure in response to a decrease in the total air volume; (g) a variable blowing pressure setting device that sets the blowing pressure corresponding to the calculated total air volume as the pressure setting value based on the relationship, and (g) a deviation between the pressure setting value and the blowing pressure on the blower discharge side detected by the pressure gauge; (h) a pressure control device that outputs a control signal according to the calculated pressure deviation; (i) a pressure deviation calculation device that calculates a blowing flow rate that makes the pressure deviation zero based on the control signal; , an air blowing flow rate setting value distribution device that allocates the calculated value of the air blowing flow rate to the air blowing flow rate setting value of each blower according to the capacity and operating status of each blower; (j) the air blowing flow rate setting for each blower; (k) a flow rate control device that controls the blower suction side control valve for each blower according to the calculated flow rate deviation; An air blowing pressure control device characterized by:
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1985027121U JPH04958Y2 (en) | 1985-02-28 | 1985-02-28 |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1985027121U JPH04958Y2 (en) | 1985-02-28 | 1985-02-28 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS61143697U JPS61143697U (en) | 1986-09-04 |
| JPH04958Y2 true JPH04958Y2 (en) | 1992-01-13 |
Family
ID=30523771
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP1985027121U Expired JPH04958Y2 (en) | 1985-02-28 | 1985-02-28 |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH04958Y2 (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2018167249A (en) | 2017-03-30 | 2018-11-01 | メタウォーター株式会社 | Wastewater treatment system, air supply amount control equipment and air supply amount control method |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5827692A (en) * | 1981-08-11 | 1983-02-18 | Toshiba Corp | Airflow controller for aeration vessel |
| JPS5841116A (en) * | 1981-09-01 | 1983-03-10 | Raito Kogyo Kk | Constructing method for slope forms |
| JPS5864191A (en) * | 1981-10-14 | 1983-04-16 | Shinko Electric Co Ltd | Method for controlling airflow |
| JPS59222299A (en) * | 1983-05-27 | 1984-12-13 | Toshiba Corp | Method for controlling aeration tank |
| JPS60102997A (en) * | 1983-11-09 | 1985-06-07 | Hitachi Ltd | Energy-conserving type controlling method for aerating air quantity |
-
1985
- 1985-02-28 JP JP1985027121U patent/JPH04958Y2/ja not_active Expired
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5827692A (en) * | 1981-08-11 | 1983-02-18 | Toshiba Corp | Airflow controller for aeration vessel |
| JPS5841116A (en) * | 1981-09-01 | 1983-03-10 | Raito Kogyo Kk | Constructing method for slope forms |
| JPS5864191A (en) * | 1981-10-14 | 1983-04-16 | Shinko Electric Co Ltd | Method for controlling airflow |
| JPS59222299A (en) * | 1983-05-27 | 1984-12-13 | Toshiba Corp | Method for controlling aeration tank |
| JPS60102997A (en) * | 1983-11-09 | 1985-06-07 | Hitachi Ltd | Energy-conserving type controlling method for aerating air quantity |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS61143697U (en) | 1986-09-04 |
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