JPS645959B2 - - Google Patents
Info
- Publication number
- JPS645959B2 JPS645959B2 JP11399782A JP11399782A JPS645959B2 JP S645959 B2 JPS645959 B2 JP S645959B2 JP 11399782 A JP11399782 A JP 11399782A JP 11399782 A JP11399782 A JP 11399782A JP S645959 B2 JPS645959 B2 JP S645959B2
- Authority
- JP
- Japan
- Prior art keywords
- sludge
- denitrification
- tank
- liquid
- solid
- 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
- 239000010802 sludge Substances 0.000 claims description 44
- 238000000034 method Methods 0.000 claims description 35
- 239000007788 liquid Substances 0.000 claims description 31
- 238000000926 separation method Methods 0.000 claims description 15
- 239000002351 wastewater Substances 0.000 claims description 10
- 238000005273 aeration Methods 0.000 claims description 7
- 238000004062 sedimentation Methods 0.000 claims description 7
- 230000005484 gravity Effects 0.000 claims description 3
- 238000005188 flotation Methods 0.000 claims description 2
- 238000005119 centrifugation Methods 0.000 claims 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 20
- 239000010800 human waste Substances 0.000 description 6
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 4
- 238000000746 purification Methods 0.000 description 4
- 241000894006 Bacteria Species 0.000 description 3
- JVMRPSJZNHXORP-UHFFFAOYSA-N ON=O.ON=O.ON=O.N Chemical compound ON=O.ON=O.ON=O.N JVMRPSJZNHXORP-UHFFFAOYSA-N 0.000 description 3
- MMDJDBSEMBIJBB-UHFFFAOYSA-N [O-][N+]([O-])=O.[O-][N+]([O-])=O.[O-][N+]([O-])=O.[NH6+3] Chemical compound [O-][N+]([O-])=O.[O-][N+]([O-])=O.[O-][N+]([O-])=O.[NH6+3] MMDJDBSEMBIJBB-UHFFFAOYSA-N 0.000 description 3
- 239000006228 supernatant Substances 0.000 description 3
- 239000002562 thickening agent Substances 0.000 description 3
- 229910001873 dinitrogen Inorganic materials 0.000 description 2
- 238000012423 maintenance Methods 0.000 description 2
- 230000014759 maintenance of location Effects 0.000 description 2
- 230000001546 nitrifying effect Effects 0.000 description 2
- XKMRRTOUMJRJIA-UHFFFAOYSA-N ammonia nh3 Chemical compound N.N XKMRRTOUMJRJIA-UHFFFAOYSA-N 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 210000000416 exudates and transudate Anatomy 0.000 description 1
- 238000006396 nitration reaction Methods 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 239000010865 sewage Substances 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
Landscapes
- Purification Treatments By Anaerobic Or Anaerobic And Aerobic Bacteria Or Animals (AREA)
Description
【発明の詳細な説明】
本発明は、曝気槽の活性汚泥を高濃度に維持し
て汚水の高負荷処理を行う方法に関するものであ
る。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for high-load treatment of sewage by maintaining activated sludge in an aeration tank at a high concentration.
従来、し尿系汚水などの有機性汚水を脱窒素を
目的として活性汚泥法で処理する場合、処理槽内
のMLSS濃度を2000〜5000mg／に維持してなさ
れていたが、近年処理効率を高めるために、処理
槽内のMLSS濃度を10000〜20000mg／と高くす
る方法が種々研究されている。 Conventionally, when organic wastewater such as human waste water was treated using the activated sludge method for the purpose of denitrification, the MLSS concentration in the treatment tank was maintained at 2000 to 5000 mg/ml, but in recent years, the MLSS concentration in the treatment tank has been maintained at 2000 to 5000 mg/ml. Various methods have been studied to increase the MLSS concentration in the treatment tank to 10,000 to 20,000 mg/.
このような生物処理においては、生物処理後に
固液の分離が行われるが、処理槽内の汚泥濃度を
高くすると固液分離工程において汚泥の沈降性が
悪くなり、沈殿槽の水面積を大きくする必要があ
る。また汚泥濃度が高いために汚泥の安定性を欠
き、時々汚泥が上澄液と共に流出することがあ
る。 In this type of biological treatment, solid-liquid separation is performed after biological treatment, but if the sludge concentration in the treatment tank is increased, the sedimentation properties of the sludge will deteriorate in the solid-liquid separation process, and the water area of the settling tank will need to be increased. There is a need. Furthermore, due to the high sludge concentration, the sludge lacks stability, and the sludge sometimes flows out together with the supernatant liquid.
このような問題に対処するため従来第１図、第
２図に示すような方法が提案されている。すなわ
ち第１図の方法は、汚水１０を曝気槽２０で処理
し、沈殿槽３０で固液分離したのち遠心分離機４
０で清澄化処理し処理水５０とするものであり、
第２図の方法は曝気槽２０からの流出液を全量遠
心分離機４０で処理するものである。なお、６０
は返送汚泥である。 In order to deal with such problems, methods as shown in FIGS. 1 and 2 have been proposed. In other words, in the method shown in FIG.
The water is clarified at 0 and becomes treated water at 50.
In the method shown in FIG. 2, all of the effluent from the aeration tank 20 is treated with a centrifuge 40. In addition, 60
is the returned sludge.
しかしながら、これらの方法には種々の問題点
がある。すなわち第１図の方法では、
沈殿槽３０で分離された沈降性のよい汚泥に
は不活性分が多く、汚泥重量当りの浄化効率が
劣り、汚泥濃度の増大に比例した浄化能力の増
大が得られないこと
沈殿槽３０からの滲流水の清澄化の装置とし
て遠心分離機４０を用いているため、その水量
負荷を、通常の汚泥処理水工程で適用する水量
負荷に比べて相当に小さくしなければならず、
従つて単位処理水量当たりの動力消費量が多大
になることである。 However, these methods have various problems. In other words, in the method shown in Fig. 1, the sludge separated in the settling tank 30 with good settling properties has a large amount of inert content, and the purification efficiency per sludge weight is poor, and the purification capacity increases in proportion to the increase in the sludge concentration. Since the centrifugal separator 40 is used as a device for clarifying the exudate water from the settling tank 30, the water load must be considerably smaller than that applied in the normal sludge treatment water process. Not necessarily,
Therefore, the amount of power consumed per unit amount of water processed becomes large.
また、第２図の方法においては、
生物処理槽流出液の全量を遠心分離機４０に
て固液分離するため、原水の濃度変動に対応し
て汚泥の処理量を円滑に加減することが難しく
維持管理が面倒であること
遠心分離液中のSS濃度を一定量以下に減少
させると同時に生物処理槽内のMLSS濃度を一
定量に維持することが難しく安定した処理を行
うことが難しいことである。 In addition, in the method shown in Figure 2, since the entire volume of the biological treatment tank effluent is separated into solid and liquid using the centrifuge 40, it is difficult to smoothly adjust the amount of sludge treated in response to changes in the concentration of raw water. Maintenance and management is troublesome. It is difficult to reduce the SS concentration in the centrifuged liquid below a certain level and at the same time maintain the MLSS concentration in the biological treatment tank at a certain level, making it difficult to perform stable treatment. .
本発明は、これらの欠点を解消するための方法
を提供することを目的としたものである。 The present invention aims to provide a method for overcoming these drawbacks.
即ち本発明は、有機性汚水を第１脱窒素工程、
硝酸化工程、第２脱窒素工程、再曝気工程の順で
処理する生物学的硝化脱窒素法において、前記第
２脱窒素工程流出液の一部を遠心濃縮工程で濃縮
汚泥と分離液に分離し、該遠心濃縮汚泥の一部を
前記第１脱窒素工程へ返送し残部を余剰汚泥とす
ると共に、前記流出液の残部と前記遠心分離液を
再曝気工程及び固液分離工程に導いて処理するこ
とを特徴とする高濃度有機性汚水の処理方法であ
る。 That is, in the present invention, organic wastewater is subjected to a first denitrification step,
In the biological nitrification and denitrification method, which processes in the order of nitrification process, second denitrification process, and reaeration process, a part of the second denitrification process effluent is separated into thickened sludge and separated liquid in a centrifugal concentration process. Then, a part of the centrifugally concentrated sludge is returned to the first denitrification process and the remaining part is used as surplus sludge, and the remaining part of the effluent and the centrifuged liquid are led to a re-aeration process and a solid-liquid separation process for treatment. This is a method for treating highly concentrated organic wastewater.
本発明の一実施態様を第３図に示すフローシー
トに従つて説明すると、
し尿系汚水などの高濃度の有機性汚水１は第１
脱窒素槽２に流入し、次の硝酸化槽３より循環さ
れてきた硝化液９と、更に遠心濃縮機５よりの濃
縮返送汚泥１０と混合処理され、脱窒素菌の働き
により硝化液９中の硝酸性窒素及び亜硝酸性窒素
を還元して窒素ガスにする。次に、硝酸化槽３で
は、汚水中のアンモニア性窒素を硝化菌の働きに
より硝酸性窒素及び亜硝酸性窒素に硝化する。 One embodiment of the present invention will be explained according to the flow sheet shown in FIG. 3. Highly concentrated organic wastewater 1 such as human waste wastewater is
The nitrification liquid 9 that flows into the denitrification tank 2 and is circulated from the next nitrification tank 3 is mixed with the concentrated return sludge 10 from the centrifugal concentrator 5, and the nitrification liquid 9 is mixed with the nitrification liquid 9 by the action of denitrification bacteria. nitrate nitrogen and nitrite nitrogen are reduced to nitrogen gas. Next, in the nitrification tank 3, ammonia nitrogen in the wastewater is nitrified into nitrate nitrogen and nitrite nitrogen by the action of nitrifying bacteria.
硝化液９の一部は次の第２脱窒素槽４に流入
し、脱窒素菌の働きにより硝酸性窒素及び亜硝酸
性窒素を窒素ガスに還元する。 A portion of the nitrifying solution 9 flows into the next second denitrification tank 4, where nitrate nitrogen and nitrite nitrogen are reduced to nitrogen gas by the action of denitrifying bacteria.
第２脱窒素槽４からの流出液の一部４ａは次の
遠心濃縮機５にかけて、その濃縮汚泥５′の一部
を上記濃縮返送汚泥１０として第１脱窒素槽２に
返送し、分離液５″は次の再曝気槽６に移送する。
なお、１２は余剰汚泥である。 A part of the effluent 4a from the second denitrification tank 4 is passed through the next centrifugal concentrator 5, and a part of the concentrated sludge 5' is returned to the first denitrification tank 2 as the concentrated return sludge 10, and the separated liquid is 5'' is transferred to the next reaeration tank 6.
In addition, 12 is surplus sludge.
本発明は、第２脱窒素槽４からの流出液の一部
４ａを遠心濃縮機５にかけて、その濃縮汚泥５′
の一部を返送汚泥、残部を余剰汚泥とすることに
特徴を有する。即ち、
汚泥を遠心濃縮機５で濃縮し、その一部を余
剰汚泥として系外に取り出すので、後続する固
液分離工程で沈殿槽７から汚泥が上澄液（処理
水８）と共に流出することを防止できること
第２脱窒素槽４内の活性ある汚泥を強制的に
濃縮し、それを第１脱窒素槽２への返送汚泥と
するので、汚泥重量当りの浄化効率を高めるこ
とができること
第２脱窒素槽４からの流出液の一部４ａを遠
心濃縮機５で処理するので、原水の濃度変動に
対して容易に対処でき、生物処理槽のMLSS濃
度を一定に維持することができ安定した生物処
理が可能であること
等の効果を得ることができる。 In the present invention, a portion 4a of the effluent from the second denitrification tank 4 is subjected to a centrifugal concentrator 5, and the concentrated sludge 5'
The feature is that a part of the sludge is returned and the rest is surplus sludge. That is, since the sludge is concentrated in the centrifugal thickener 5 and a part of it is taken out of the system as surplus sludge, the sludge does not flow out from the settling tank 7 together with the supernatant liquid (treated water 8) in the subsequent solid-liquid separation process. The active sludge in the second denitrification tank 4 is forcibly concentrated and returned to the first denitrification tank 2 as sludge, so the purification efficiency per sludge weight can be increased. Since a portion 4a of the effluent from the denitrification tank 4 is treated with the centrifugal concentrator 5, fluctuations in the concentration of raw water can be easily dealt with, and the MLSS concentration in the biological treatment tank can be maintained constant and stable. Effects such as the possibility of biological treatment can be obtained.
次に、第２脱窒素槽４からの流出液の残部４ｂ
は遠心濃縮機５による上記分離液５″と共に再曝
気槽６に移送し脱気を行なう。分離液５″中には
通常微細な気泡が含有されるので、後続する沈殿
槽７における汚泥の浮上を防止すると共に、第２
脱窒素処理で残留するNOxを硝化する。 Next, the remainder 4b of the effluent from the second denitrification tank 4 is
The separated liquid 5'' from the centrifugal concentrator 5 is transferred to the re-aeration tank 6 for deaeration.Since the separated liquid 5'' normally contains fine air bubbles, the sludge floats to the surface in the subsequent settling tank 7. In addition to preventing
Nitrifies the NO x remaining in the denitrification process.
次に、再曝気処理液を沈殿槽７に流入させ、重
力式沈降分離法により汚泥の固液分離を行なう。
従来の処理方法だと固液分離工程として機械的分
離法を使用せざるを得ないのであるが、本発明方
法においては前記のように、前段階で遠心濃縮機
５により汚泥の一部を余剰汚泥として系外に排出
しているので、沈殿槽流入混合液の汚泥濃度を
1000〜3000mg／に下ることができ、沈殿槽７で
の汚泥負荷を小さくすることができる。この結
果、沈殿槽上澄液すなわち処理水８の水質も向上
し、処理の安定性も増加する。 Next, the reaeration treatment liquid is caused to flow into the settling tank 7, and solid-liquid separation of the sludge is performed by gravity sedimentation separation method.
Conventional treatment methods have no choice but to use a mechanical separation method as a solid-liquid separation step, but in the method of the present invention, as mentioned above, a portion of the excess sludge is removed using the centrifugal thickener 5 in the previous stage. Since it is discharged outside the system as sludge, the sludge concentration of the mixed liquid flowing into the sedimentation tank is
The sludge load in the settling tank 7 can be reduced to 1000 to 3000 mg/. As a result, the quality of the sedimentation tank supernatant liquid, that is, the treated water 8, is improved, and the stability of the treatment is also increased.
なお、重力式沈殿槽７の代りに加圧浮上分離装
置を設ける場合には、再曝気槽６のような脱気の
必要はなく、上記流出液４ｂと分離液５″の単な
る混合槽を設ければよい。なお、１１は余剰汚泥
である。 Note that when a pressure flotation separation device is provided in place of the gravity settling tank 7, there is no need for deaeration as in the re-aeration tank 6, and a simple mixing tank for the effluent 4b and separated liquid 5'' is provided. Note that 11 is excess sludge.
次に本発明の実施例を示す。 Next, examples of the present invention will be shown.
実施例 １
下記の水質を有する生し尿を第３図に示す生物
学的硝化脱窒素法により無希釈生物処理した。Example 1 Human waste having the following water quality was subjected to undiluted biological treatment by the biological nitrification and denitrification method shown in FIG.
１ 生し尿の水質
BOD 12000〜20000mg／
NH4−Ｎ 3000〜5000 〃
CODMo 5000〜8000 〃
２ 処理プロセスの仕様 運転条件
第１脱窒素槽滞留時間 ３日
硝酸化槽滞留時間 ５日
第２脱窒素槽滞留時間 １日
硝化液循環量 生し尿流入量の30倍
遠心濃縮機処理量 〃 の1.3倍
濃縮汚泥返送量 〃 の0.5倍
生物処理工程内MLSS 10000〜20000mg／
硝酸化槽内DOレベル １〜４mg／
余剰汚泥量１２ 生し尿流入量の0.05倍
〃 １１ 〃 の0.40倍
第２脱窒素槽からの流出液の10〜20％を遠心濃
縮機に供給し、遠心濃縮汚泥（SS濃度４〜５％）
の80％〜90％を第１脱窒素槽に返送した。第２脱
窒素槽流出液の残部と遠心濃縮機分離液を再曝気
槽（滞留時間0.5〜１日）に流入せしめ充分曝気
処理したのち、重力式沈殿槽（滞留時間1.5〜２
日）に導入して固液分離処理した。沈殿槽越流水
の水質は下記のとおりであり、無希釈処理水とし
て良好なものであつた。1 Water quality of raw human waste BOD 12000~20000mg/ NH 4 -N 3000~5000 〃 COD Mo 5000~8000 〃 2 Treatment process specifications Operating conditions Residence time in the first denitrification tank 3 days Residence time in the nitrification tank 5 days Second denitrification Nitrogen tank retention time 1 day Nitrification liquid circulation volume 30 times the raw human waste inflow volume Centrifugal concentrator processing volume 1.3 times of 〃 Thickened sludge return volume 0.5 times of 〃 MLSS in biological treatment process 10,000 to 20,000 mg/DO level in nitrification tank 1 〜4 mg/ Surplus sludge amount 12 0.05 times the raw human waste inflow 〃 11 〃 0.40 times 10 to 20% of the effluent from the second denitrification tank is supplied to the centrifugal thickener, and centrifugally thickened sludge (SS concentration 4 to 5%)
80% to 90% of the amount was returned to the first denitrification tank. The remainder of the effluent from the second denitrification tank and the centrifugal concentrator separated liquid are flowed into a re-aeration tank (retention time 0.5 to 1 day) and sufficiently aerated.
(Japan) and subjected to solid-liquid separation treatment. The water quality of the settling tank overflow water was as shown below, and was good as undiluted treated water.
３ 沈殿槽越流水の水質
BOD 20〜60mg／
CODMo 100〜300 〃
NH4−Ｎ 10〜15 〃
NOx−Ｎ 20〜50 〃
SS 30〜50 〃
以上述べたように、本発明によれば高濃度の有
機性汚水を安定して、かつ高い浄化効率で処理す
ることができ、運転操作・維持管理も極めて簡便
に行なえるなどの効果が得られる。3 Water quality of sedimentation tank overflow water BOD 20-60 mg/ COD Mo 100-300 〃 NH 4 -N 10-15 〃 NO x -N 20-50 〃 SS 30-50 〃 As described above, according to the present invention Highly concentrated organic wastewater can be treated stably and with high purification efficiency, and operation and maintenance can be performed extremely easily.
第１図及び第２図は、いずれも従来方法の代表
例を示すフローシート、第３図は、本発明の一実
施態様を示すフローシートである。
１……有機性汚水、２……第１脱窒素槽、３…
…硝酸化槽、４……第２脱窒素槽、５……遠心濃
縮機、６……再曝気槽、７……沈殿槽、８……処
理水、９……硝化液、１０……濃縮返送汚泥、１
１，１２……余剰汚泥。
1 and 2 are flow sheets showing typical examples of conventional methods, and FIG. 3 is a flow sheet showing one embodiment of the present invention. 1... Organic wastewater, 2... First denitrification tank, 3...
... Nitration tank, 4 ... Second denitrification tank, 5 ... Centrifugal concentrator, 6 ... Reaeration tank, 7 ... Sedimentation tank, 8 ... Treated water, 9 ... Nitrification liquid, 10 ... Concentration Returned sludge, 1
1, 12...excess sludge.
Claims (1)
第２脱窒素工程、再曝気工程の順で処理する生物
学的硝化脱窒素法において、 前記第２脱窒素工程流出液の一部を遠心濃縮工
程で濃縮汚泥と分離液に分離し、該遠心濃縮汚泥
の一部を前記第１脱窒素工程へ返送し残部を余剰
汚泥とすると共に、前記流出液の残部と前記遠心
分離液を再曝気工程及び固液分離工程に導いて処
理することを特徴とする高濃度有機性汚水の処理
方法。 ２ 前記固液分離工程が、前記再曝気工程の後段
に設けられ、重力式沈降分離法により行なわれる
ものである特許請求の範囲第１項記載の方法。 ３ 前記再曝気工程及び固液分離工程が、加圧浮
上分離工程により並行して行なわれるものである
特許請求の範囲第１項記載の方法。[Claims] 1 Organic wastewater is subjected to a first denitrification process, a nitrification process,
In the biological nitrification denitrification method in which the second denitrification step and the reaeration step are performed in this order, a part of the second denitrification step effluent is separated into thickened sludge and separated liquid in a centrifugal concentration step, and the centrifugation A part of the concentrated sludge is returned to the first denitrification process and the remaining part is used as surplus sludge, and the remaining part of the effluent and the centrifuged liquid are led to a re-aeration process and a solid-liquid separation process for treatment. A method for treating highly concentrated organic wastewater. 2. The method according to claim 1, wherein the solid-liquid separation step is provided after the reaeration step and is performed by a gravity sedimentation separation method. 3. The method according to claim 1, wherein the reaeration step and the solid-liquid separation step are performed in parallel by a pressure flotation separation step.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP11399782A JPS596996A (en) | 1982-07-02 | 1982-07-02 | Treatment of organic filthy water of high concentration |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP11399782A JPS596996A (en) | 1982-07-02 | 1982-07-02 | Treatment of organic filthy water of high concentration |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS596996A JPS596996A (en) | 1984-01-14 |
| JPS645959B2 true JPS645959B2 (en) | 1989-02-01 |
Family
ID=14626469
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP11399782A Granted JPS596996A (en) | 1982-07-02 | 1982-07-02 | Treatment of organic filthy water of high concentration |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS596996A (en) |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS59154197A (en) * | 1983-02-21 | 1984-09-03 | Showa Denko Kk | Biological denitrification method of organic waste |
| JPS60238199A (en) * | 1984-05-10 | 1985-11-27 | Kurita Water Ind Ltd | Method for keeping activity of sludge in biological nitration and denitrification treatment apparatus |
| JPH06102956B2 (en) * | 1986-12-01 | 1994-12-14 | 石川島播磨重工業株式会社 | Shield machine |
| JPS6422400A (en) * | 1987-07-18 | 1989-01-25 | Kajima Corp | Waste water treatment |
| JPH0626629Y2 (en) * | 1988-10-26 | 1994-07-20 | 東京電力株式会社 | Shield machine |
-
1982
- 1982-07-02 JP JP11399782A patent/JPS596996A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS596996A (en) | 1984-01-14 |
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