JPS6345635B2 - - Google Patents
Info
- Publication number
- JPS6345635B2 JPS6345635B2 JP5184083A JP5184083A JPS6345635B2 JP S6345635 B2 JPS6345635 B2 JP S6345635B2 JP 5184083 A JP5184083 A JP 5184083A JP 5184083 A JP5184083 A JP 5184083A JP S6345635 B2 JPS6345635 B2 JP S6345635B2
- Authority
- JP
- Japan
- Prior art keywords
- activated sludge
- water
- sludge treatment
- compounds
- phosphorus
- 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 78
- 238000011282 treatment Methods 0.000 claims description 49
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 43
- NBIIXXVUZAFLBC-UHFFFAOYSA-N phosphoric acid Substances OP(O)(O)=O NBIIXXVUZAFLBC-UHFFFAOYSA-N 0.000 claims description 31
- 150000003018 phosphorus compounds Chemical class 0.000 claims description 30
- -1 phosphoric acid compound Chemical class 0.000 claims description 29
- 229910000147 aluminium phosphate Inorganic materials 0.000 claims description 24
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 claims description 20
- IMQLKJBTEOYOSI-GPIVLXJGSA-N Inositol-hexakisphosphate Chemical compound OP(O)(=O)O[C@H]1[C@H](OP(O)(O)=O)[C@@H](OP(O)(O)=O)[C@H](OP(O)(O)=O)[C@H](OP(O)(O)=O)[C@@H]1OP(O)(O)=O IMQLKJBTEOYOSI-GPIVLXJGSA-N 0.000 claims description 20
- 238000005273 aeration Methods 0.000 claims description 19
- 238000000034 method Methods 0.000 claims description 19
- 235000002949 phytic acid Nutrition 0.000 claims description 19
- 229910052698 phosphorus Inorganic materials 0.000 claims description 18
- 239000011574 phosphorus Substances 0.000 claims description 18
- IMQLKJBTEOYOSI-UHFFFAOYSA-N Phytic acid Natural products OP(O)(=O)OC1C(OP(O)(O)=O)C(OP(O)(O)=O)C(OP(O)(O)=O)C(OP(O)(O)=O)C1OP(O)(O)=O IMQLKJBTEOYOSI-UHFFFAOYSA-N 0.000 claims description 14
- 239000000467 phytic acid Substances 0.000 claims description 14
- 229940068041 phytic acid Drugs 0.000 claims description 14
- 239000000126 substance Substances 0.000 claims description 6
- 150000003016 phosphoric acids Chemical class 0.000 claims description 5
- 238000004062 sedimentation Methods 0.000 claims description 2
- 241000894006 Bacteria Species 0.000 description 21
- 230000007257 malfunction Effects 0.000 description 18
- OAICVXFJPJFONN-UHFFFAOYSA-N Phosphorus Chemical compound [P] OAICVXFJPJFONN-UHFFFAOYSA-N 0.000 description 15
- NJYFRQQXXXRJHK-UHFFFAOYSA-N (4-aminophenyl) thiocyanate Chemical class NC1=CC=C(SC#N)C=C1 NJYFRQQXXXRJHK-UHFFFAOYSA-N 0.000 description 11
- 241000209094 Oryza Species 0.000 description 9
- 235000007164 Oryza sativa Nutrition 0.000 description 9
- 235000009566 rice Nutrition 0.000 description 9
- 102000004190 Enzymes Human genes 0.000 description 6
- 108090000790 Enzymes Proteins 0.000 description 6
- 235000013343 vitamin Nutrition 0.000 description 6
- 239000011782 vitamin Substances 0.000 description 6
- 229940088594 vitamin Drugs 0.000 description 6
- 229930003231 vitamin Natural products 0.000 description 6
- 229910019142 PO4 Inorganic materials 0.000 description 5
- TWJVNKMWXNTSAP-UHFFFAOYSA-N azanium;hydroxide;hydrochloride Chemical compound [NH4+].O.[Cl-] TWJVNKMWXNTSAP-UHFFFAOYSA-N 0.000 description 5
- 239000010452 phosphate Substances 0.000 description 5
- 150000003839 salts Chemical class 0.000 description 5
- 230000035939 shock Effects 0.000 description 5
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 4
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 4
- 238000005516 engineering process Methods 0.000 description 4
- 229910052816 inorganic phosphate Inorganic materials 0.000 description 4
- 239000002184 metal Substances 0.000 description 4
- 229910052751 metal Inorganic materials 0.000 description 4
- 150000003013 phosphoric acid derivatives Chemical class 0.000 description 4
- 238000011084 recovery Methods 0.000 description 4
- 238000007796 conventional method Methods 0.000 description 3
- 230000007423 decrease Effects 0.000 description 3
- 150000002989 phenols Chemical class 0.000 description 3
- 241000196324 Embryophyta Species 0.000 description 2
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 2
- 229910021529 ammonia Inorganic materials 0.000 description 2
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 2
- 230000001580 bacterial effect Effects 0.000 description 2
- 230000015271 coagulation Effects 0.000 description 2
- 238000005345 coagulation Methods 0.000 description 2
- 239000003245 coal Substances 0.000 description 2
- 238000000354 decomposition reaction Methods 0.000 description 2
- 239000013505 freshwater Substances 0.000 description 2
- 229910052739 hydrogen Inorganic materials 0.000 description 2
- 239000001257 hydrogen Substances 0.000 description 2
- 229910052742 iron Inorganic materials 0.000 description 2
- 150000002825 nitriles Chemical class 0.000 description 2
- 235000015097 nutrients Nutrition 0.000 description 2
- 239000003921 oil Substances 0.000 description 2
- 235000019198 oils Nutrition 0.000 description 2
- 230000033116 oxidation-reduction process Effects 0.000 description 2
- 229910052760 oxygen Inorganic materials 0.000 description 2
- 239000001301 oxygen Substances 0.000 description 2
- 230000035755 proliferation Effects 0.000 description 2
- 239000013535 sea water Substances 0.000 description 2
- 239000010865 sewage Substances 0.000 description 2
- 238000001179 sorption measurement Methods 0.000 description 2
- 150000003568 thioethers Chemical class 0.000 description 2
- 235000015112 vegetable and seed oil Nutrition 0.000 description 2
- 239000008158 vegetable oil Substances 0.000 description 2
- 235000015099 wheat brans Nutrition 0.000 description 2
- QTWJRLJHJPIABL-UHFFFAOYSA-N 2-methylphenol;3-methylphenol;4-methylphenol Chemical compound CC1=CC=C(O)C=C1.CC1=CC=CC(O)=C1.CC1=CC=CC=C1O QTWJRLJHJPIABL-UHFFFAOYSA-N 0.000 description 1
- QGZKDVFQNNGYKY-UHFFFAOYSA-O Ammonium Chemical compound [NH4+] QGZKDVFQNNGYKY-UHFFFAOYSA-O 0.000 description 1
- VHUUQVKOLVNVRT-UHFFFAOYSA-N Ammonium hydroxide Chemical class [NH4+].[OH-] VHUUQVKOLVNVRT-UHFFFAOYSA-N 0.000 description 1
- 244000068988 Glycine max Species 0.000 description 1
- 235000010469 Glycine max Nutrition 0.000 description 1
- 208000001953 Hypotension Diseases 0.000 description 1
- ISWSIDIOOBJBQZ-UHFFFAOYSA-N Phenol Chemical compound OC1=CC=CC=C1 ISWSIDIOOBJBQZ-UHFFFAOYSA-N 0.000 description 1
- 244000000231 Sesamum indicum Species 0.000 description 1
- 235000003434 Sesamum indicum Nutrition 0.000 description 1
- 206010066901 Treatment failure Diseases 0.000 description 1
- 230000002159 abnormal effect Effects 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
- 241001148470 aerobic bacillus Species 0.000 description 1
- 235000011114 ammonium hydroxide Nutrition 0.000 description 1
- BFNBIHQBYMNNAN-UHFFFAOYSA-N ammonium sulfate Chemical compound N.N.OS(O)(=O)=O BFNBIHQBYMNNAN-UHFFFAOYSA-N 0.000 description 1
- 229910052921 ammonium sulfate Inorganic materials 0.000 description 1
- 235000011130 ammonium sulphate Nutrition 0.000 description 1
- 230000033228 biological regulation Effects 0.000 description 1
- 238000010000 carbonizing Methods 0.000 description 1
- 235000013339 cereals Nutrition 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 239000000571 coke Substances 0.000 description 1
- 229930003836 cresol Natural products 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 238000007865 diluting Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 230000003203 everyday effect Effects 0.000 description 1
- 150000002484 inorganic compounds Chemical class 0.000 description 1
- 229910010272 inorganic material Inorganic materials 0.000 description 1
- 238000002386 leaching Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 230000002503 metabolic effect Effects 0.000 description 1
- 150000002903 organophosphorus compounds Chemical class 0.000 description 1
- 230000001590 oxidative effect Effects 0.000 description 1
- 238000001556 precipitation Methods 0.000 description 1
- 230000002035 prolonged effect Effects 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 238000007670 refining Methods 0.000 description 1
- 159000000000 sodium salts Chemical class 0.000 description 1
- 150000004764 thiosulfuric acid derivatives Chemical class 0.000 description 1
- 235000013311 vegetables Nutrition 0.000 description 1
- 239000002351 wastewater Substances 0.000 description 1
- 150000003739 xylenols Chemical class 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
本発明は安水の活性汚泥処理法に関するもの
で、さらに詳述すると安水の活性汚泥処理を不調
を起すことなく順調に処理し、しかも活性汚泥処
理水中の無機性リン化合物の濃度を１mg／以下
に管理する方法である。
安水は、石炭を乾留してコークスを製造する際
に原料の石炭の約10〜15％発生する。安水はフエ
ノール、クレゾール、キシレノールなどの有機物
およびアンモニア化合物、シアン化合物、ロダン
化合物、チオ硫酸化合物、硫化物などの無機化合
物を含有しており、化学的酸素要求量（COD）
も5000〜10000mg／と高く、また、濃茶褐色を
呈しており、このまゝでは公共用水域に排出する
ことができない。
この安水の無害化処理は、残留法などの常法に
よりアンモニア化合物の一部を除去した後、海水
およびまたは淡水により２〜６倍に希釈し、活性
汚泥（バクテリヤ）の栄養源として無機性リン酸
化合物を生物学的酸素要求量（BOD）100重量部
に対して約１重量部（リンとして）添加して活性
汚泥処理を行うのが通常の方法である。
本発明者らは、この無機性リン酸化合物の添加
量にもとづいて安水の活性汚泥処理を行つた結
果、無機性リン酸化合物としてリン酸を使用した
場合、活性汚泥（バクテリヤ）に利用されている
リン酸は20〜60％に過ぎず、残りは処理水に流出
することが判明した。処理水中のリン化合物が１
mg／をこえる場合には、そのまま公共用水域に
放出すると赤潮等の廃水害の原因になるおそれが
あり好ましくないので無機性リン酸化合物の除去
工程を余分に設ける必要がある。
そこで、処理水の無機性リン酸化合物を減少さ
せる目的で、活性汚泥処理装置の曝気槽に添加す
る無機性リン酸化合物を減らした所、処理水の無
機性リン酸化合物は減少するが、活性汚泥処理の
不調、たとえば、ロダン化合物などのCOD成分
の分解性不良、活性汚泥のバルキングなどの処理
不調が起り易くなることが判明した。このため、
活性汚泥処理の処理不調を起さず、しかも活性汚
泥処理水のリン化合物の濃度を１mg／以下にす
ることはかなり困難である。
そこで、本発明者らは活性汚泥処理の代謝機構
にADP（アデノシリン、２−リン酸エステル）、
ATP（アデノシリン、３−リン酸エステル）など
の有機性リン酸化合物が関与していることに着目
し、各種の有機性リン化合物について検討した。
その結果、有機性リン酸エステルであるフイチン
酸（C6H6（OPO3H2）6）および水溶性フイチン酸
たとえばナトリウム塩を活性汚泥処理の曝気槽に
添加すると、活性汚泥（バクテリヤ）によるリン
の有効利用率は、ほゞ100％であり、処理水にほ
とんどリン化合物が流出しないことを見出した。
また、この有機性リン酸エステルと無機性リン
酸化合物とを併用すると無機性リン酸化合物自体
の活性汚泥による有効利用率も約78〜83％に向上
することを見い出した。したがつて、この有機性
リン酸エステルと無機性リン酸化合物とを併用す
ると有機リン酸化合物の利用効率が良いうえに活
性汚泥による無機性リン酸化合物の有効率も大幅
に向上するため、無機性リン酸化合物の曝気槽へ
の添加量を大幅に減少させることができ、しかも
処理水へのリン化合物の流出を大巾に減少できる
ことがわかつた。
又、安水の活性汚泥処理は、フエノール系化合
物、ロダン化合物などのCOD成分の大部分を分
解除去する重要なプロセスであるにもかゝらず、
都市下水などの活性汚泥処理の設備、関理、操業
条件などをそのまゝ模倣している。しかし、安水
は都市下水などに比べて組成的に複雑であり、ま
た、シアン化合物、硫化物など活性汚泥の機能を
阻害する成分を含有しているので、都市下水など
の活性汚泥の設備仕様、管理、操業技術などを、
そのまま安水に適用するには限界がある。
このため、従来の安水活性汚泥処理は、原因不
明の処理不調が発生しやすく、また、処理不調が
発生すると、原因、対策および回復技術などが明
らかにされていないため、その回復方法は試行錯
誤的であり、回復に１〜６ケ月の長期間を要する
ことがある。
さらに、処理不調が発生した場合の重要な問題
点は、処理不調の多くのケースにおいて、ロダン
化合物の分解性が低下し処理水質が悪化すること
である。この処理水中のロダン化合物は、鉄凝集
沈澱法、活性炭吸着法などの物理化学的処理によ
つても除去困難であり、現在のところ、活性汚泥
処理以外の方法では経済的にしかも効率的に除去
する技術が確立されていない。従つて、このよう
な場合、活性汚泥処理の後に鉄凝集沈澱法、活性
炭吸着法などの追加処理設備を設置してもロダン
化合物は、この処理設備を素通りして除去するこ
とができない。
このロダン化合物を分解する菌（ロダン資化
菌）は、フエノールなどを分解する菌に比べて増
殖性が著しく遅く、本発明者の研究によると毒性
物質、PHなどのシヨツクによりロダン資化菌の機
能が低下した場合、これらのシヨツクを取り除い
た後、機能がシヨツク以前の状態に回復するのに
20〜60日も要することが明らかになつている。こ
の期間は、処理水のCOD、ロダン濃度が高い状
態が続くことになる。
もう一つの重要な問題点は、製鉄所から発生す
るCOD量のうち安水関係に起因するCODが約50
〜70％と最も高い比率を占めており、安水の活性
汚泥処理の不調が発生し、処理不調が長期化する
と環境排出規制を遵守できなくなる懸念がある。
本発明者らは、すでに安水の処理に適した処理
技術を確立しているが、処理不調に対しては必ず
しも十分対処できなかつた。そこで本発明は、安
水の活性汚泥処理の不調を予防して順調に処理し
しかも処理水のリン化合物の濃度を１mg／以下
に維持する技術を完成するに至つたものである。
安水の活性汚泥の機能を阻害する成分によるシ
ヨツク、あるいは異常PHによるシヨツクによる活
性汚泥の処理不調は、これらのシヨツクにより活
性汚泥を構成しているバクテリヤ（資化菌）がか
なり死滅していることに起因している。
したがつて、処理不調が正常な処理状態に回復
するためには、まず、シヨツクにより減少したバ
クテリヤを増殖させて正常な処理を行なつていた
時の状態に回復しなければならない。
処理不調の活性汚泥を正常な状態に回復させる
方法は、処理不調になつた原因を取り除いて活性
汚泥処理のPH、温度、DOなどを適正な条件に管
理する方法が最も普遍的である。
しかし、活性汚泥は各種バクテリヤの集合体で
あり、各バクテリヤの性状がかなり異なつている
ことが考えられる。たとえば、先に説明したよう
にロダン資化菌の増殖速度は非常に遅く、例えば
フエノール系化合物を分解するバクテリヤの約1/
４０である。したがつて、安水の活性汚泥処理の不
調を短期間に回復させるためには、ロダン資化菌
のように増殖速度の遅いバクテリヤの増殖速度を
促進する必要がある。
従来の不調の回復方法は、活性汚泥処理の条件
すなわち、温度、PH、DOなどを管理しバクテリ
ヤの自然増殖を期待するに過ぎず、このような方
法では処理不調の回復は、先に説明したように長
期間を要する。
そこで本発明者らは、安水活性汚泥処理の不調
を短期間に回復させるためにバクテリヤ、特に、
ロダン資化菌の増殖を促進させて処理不調を短期
間に回復させる方法を完成してすでに特許出願済
みである。
即ち、一般に、バクテリヤは微量のビタミン、
金属塩、酵素などが存在すると増殖速度が促進さ
れることが知られている。本発明者らは、この点
に着目し、ビタミン、金属塩、酵素などを安水活
性汚泥処理の曝気槽に添加し、バクテリヤの増殖
速度を測定した結果、ロダン資化菌を例にとると
無添加の場合に比べて増殖速度が約２〜５倍も促
進されることを知見した。これらの結果から、活
性汚泥処理の不調が発生した場合、ビタミン、酵
素、金属塩などを添加すると不調が短期間に回復
することが考えられる。
そこで、実際に不調が発生した活性汚泥処理に
添加した結果、ロダン化合物の分解不良の回復
は、従来の方法が20〜60日間も要したのに対して
ビタミン、金属塩、酵素などを添加することによ
り７〜10日間で回復した。
しかし、実設備の処理不調にこの方法を適用す
ると大量のビタミン、酵素などを必要とし、コス
ト的に問題があり実用化はかなり困難である。そ
こで本発明者らはビタミン、酵素などに代るもの
について検討した結果、米ヌカ、フスマ、植物油
を製造する際に発生する油かす、フイテン酸又は
その塩などの有機性燐酸化合物、又はそれらの含
有物が最適であることを見出し既に特許出願済み
である。
本発明者らは引続き研究を行つた結果、前記の
バクテリヤ増殖剤を無機性リン酸化合物と併用し
て常時少量添加することにより活性汚泥処理の不
調を予防できることも見い出したものである。
この結果にもとづき、活性汚泥処理が順調に行
われ、また、処理水のリン化合物の濃度を１mg／
以下に維持する条件を検討した結果、COD容
積負荷量が１〜３Kg／m3・日の安水の活性汚泥処
理の場合、曝気槽１m3当り、１日にフイチン酸ま
たは水溶性フイチン酸塩を１〜５ｇ、無機性リン
酸化合物を３〜４ｇ（リンとして）連続的に添加
すれば良いことが判明した。
また、フイチン酸および水溶性フイチン酸塩
は、無機性リン酸化合物に比べてかなり高価であ
るため、これらのフイチン酸に代るものとして、
こく物を精製する時に発生する米ヌカ、フスマな
ど、あるいは、大豆、ゴマなどの植物の種より植
物油を製造する際に発生する米カスなどを使用し
たところ同様の良い結果が得られた。
これは、こく物あるいは植物の種にはフイチン
酸がかなり含有されており、フイチン酸の多くは
米ヌカなどから抽出して製造している。たとえ
ば、米ヌカの場合、リンを１〜1.5％程度含有し
ており、フイチン酸として４〜７％程度に相当す
る。
したがつて、フイチン酸および水溶性フイチン
酸塩に代る安価なものとして、米ヌカ、フスマ、
油カスなどを使用すると経済的にも有利であり、
この時の添加量は、曝気槽１m3当り１日に10〜50
ｇ程度が最適である。
次に、活性汚泥処理水のリン化合物の濃度を、
無機性リン酸化合物の添加量の調整により１mg／
以下にする方法について説明する。
本発明では、安水の活性汚泥処理の曝気槽に、
フイチン酸、水溶性のフイチン酸塩、フイチン酸
を含む物質の内１種類または２種類以上を好まし
くは１日に１回〜３回に分割して所定量を添加す
る。一方無機性リン酸化合物の添加方法は、活性
汚泥処理水のリン化合物の濃度を測定し、濃度が
１ｇ／m3以下になるように供給原水または曝気槽
に連続的に添加する。具体的にはもし、処理水の
リン化合物の濃度が0.5ｇ／m3以上になつたら、
徐々に無機性リン酸化合物の添加量を減少させ、
好ましくは処理水のリン化合物濃度を0.2〜0.5
ｇ／m3に維持することにより１mg／以下に維持
することができる。一方、リン化合物の濃度が
0.2ｇ／m3以下になるようであつたら無機性リン
酸化合物の添加量を増加させると同時にフイチン
酸、又はフイチン酸塩、若しくはこれらの含有物
の添加量を減少させるのが好ましい。
次に、活性汚泥処理装置の活性汚泥沈降槽の酸
化還元電位（ORP）と処理水のリン化合物の濃
度との関係について説明する。一般に、好気性活
性汚泥処理においては、曝気槽が好気性環境であ
るが活性汚泥沈降槽は嫌気性環境である。好気性
活性汚泥（バクテリヤ）は、好気性環境において
はリン化合物を細胞内に取り入れるが、この好気
性バクテリヤが嫌気性環境におかれると細胞内に
取り入れたリン化合物を放出する傾向がある。
したがつて、バクテリヤ細胞内のリン化合物を
測定すると、曝気槽における活性汚泥のリン化合
物の含有量は、活性汚泥沈降槽の活性汚泥よりも
高く、また、沈降槽における滞留時間が長いほど
活性汚泥のリン化合物の含有量が低くなり、処理
水のリン化合物の濃度が高くなる傾向がある。
このことから、活性汚泥沈降槽が嫌気性になる
のを防げば活性汚泥よりのリン化合物の放出を抑
制することができ活性汚泥処理水のリン化合物の
濃度を低下させることができる。この活性汚泥沈
降槽の嫌気性、好気性の管理指標として酸化還元
電位（以下ORPと略記）を管理するのが最適で
ある。
本発明者らの研究によると、活性汚泥がリン化
合物を放出しないORPは、約＋100〜200ｍｖ（水
素電極を基準にした場合）以上であることが判明
したので、活性汚泥沈降槽のORPを約＋100〜
200ｍｖ以上に維持すれば活性汚泥のリンの放出
が減少し、処理水のリン濃度が減少することが考
えられる。
一般に、好気性活性汚泥処理においては、曝気
槽と汚泥沈降槽のORPの差異は、約100〜200ｍ
ｖであり、曝気槽を高いORP、すなわち、より
好気性（酸化性）環境に維持すれば、汚泥沈降槽
のORPも高くなる。したがつて、安水の活性汚
泥処理の場合、曝気槽のORPを400〜480ｍｖ
（NHE基準）に常時管理すれば、汚泥沈降槽の
ORPは、活性汚泥がリンを放出しにくい条件に
維持することができる。
このことから、安水の活性汚泥処理は、曝気槽
のORPを400〜480ｍＶの範囲に管理し、さらに、
汚泥沈降槽のOPRを＋100〜200ｍＶ以上に、そ
れぞれ管理すれば、活性汚泥がリン化合物を放出
しにくくなる。
このようなORP管理に加えてさらに、活性汚
泥が栄養源として利用しやすいフイチン酸、水溶
性フイチン酸塩およびフイチン酸を含む物質と無
機リン酸化合物を併用すれば、処理不調を起すこ
となく順調に処理でき、しかも無機性リン化合物
の添加量をコントロールすることにより、処理水
のリン化合物の濃度を１mg／以下に維持するこ
とができ、また、円滑な処理と無機性リン化合物
使用量の大幅な削減が可能になつた。
次に、本発明の実施例について説明する。
実施例 １
常法のアンモニアストリツピング処理により、
遊離アンモニア化合物の85〜90％以上を除去した
安水を、海水と淡水により４倍稀釈したものを供
給原水として、COD容積負荷量1.5Kg／m3・日で、
曝気槽のORPを＋430±10ｍＶに管理しながら、
米ヌカを曝気槽（3300m3）に８時間毎に30Kg添加
（30ppm）して活性汚泥処理を行つた。このよう
な条件で活性汚泥処理を行うと、汚泥沈降槽の
ORPは約250ｍＶになる。
なお、無機リン化合物は、供給原水にリン酸を
添加した。
表−１は、供給原水に添加したリン酸の濃度
（燐として表示）と処理水の燐濃度との関係を示
したものである。
The present invention relates to an activated sludge treatment method for ammonium chloride water. More specifically, the present invention relates to an activated sludge treatment method for ammonium chloride water, and more specifically, it is capable of smoothly processing activated sludge treatment of ammonium chloride water without causing any problems, and furthermore, the concentration of inorganic phosphorus compounds in the activated sludge treatment water can be reduced to 1 mg/ml. The following is the method of management. Ammonium water is generated by approximately 10 to 15% of the raw material coal when producing coke by carbonizing coal. Ammonium water contains organic substances such as phenol, cresol, and xylenol, and inorganic compounds such as ammonia compounds, cyanide compounds, rhodan compounds, thiosulfate compounds, and sulfides, and has a high chemical oxygen demand (COD).
The concentration is high at 5,000 to 10,000mg/, and the color is dark brown, so it cannot be discharged into public water bodies in this state. This ammonia water is detoxified by removing a part of the ammonia compound using a conventional method such as the residual method, and then diluting it 2 to 6 times with seawater and/or fresh water to make it inorganic as a nutrient source for activated sludge (bacteria). The usual method is to perform activated sludge treatment by adding about 1 part by weight (as phosphorus) of a phosphoric acid compound per 100 parts by weight of biological oxygen demand (BOD). The present inventors conducted activated sludge treatment with ammonium water based on the amount of the inorganic phosphoric acid compound added, and found that when phosphoric acid was used as the inorganic phosphoric acid compound, it was not used in the activated sludge (bacteria). It was found that only 20-60% of the phosphoric acid was present in the water, with the rest leaching into the treated water. Phosphorus compounds in treated water are 1
mg/, it is not preferable to release it directly into public water bodies as it may cause wastewater damage such as red tide, so it is necessary to provide an extra step to remove the inorganic phosphoric acid compound. Therefore, in order to reduce the inorganic phosphate compounds in the treated water, we reduced the amount of inorganic phosphate compounds added to the aeration tank of the activated sludge treatment equipment, and although the inorganic phosphate compounds in the treated water decreased, It has been found that malfunctions in sludge treatment, such as poor decomposition of COD components such as rhodan compounds and bulking of activated sludge, are more likely to occur. For this reason,
It is quite difficult to reduce the concentration of phosphorus compounds in activated sludge treated water to 1 mg/l or less without causing malfunctions in activated sludge treatment. Therefore, the present inventors added ADP (adenocillin, 2-phosphate ester) to the metabolic mechanism of activated sludge treatment.
Focusing on the involvement of organic phosphoric acid compounds such as ATP (adenosyline, 3-phosphate ester), various organic phosphorus compounds were investigated.
As a result, when phytic acid (C 6 H 6 (OPO 3 H 2 ) 6 ), an organic phosphate ester, and water-soluble phytic acid, such as sodium salt, are added to an aeration tank for activated sludge treatment, activated sludge (bacteria) It was found that the effective utilization rate of phosphorus was almost 100%, and almost no phosphorus compounds were leaked into the treated water. Furthermore, it has been found that when this organic phosphate ester and an inorganic phosphoric acid compound are used in combination, the effective utilization rate of the inorganic phosphoric acid compound itself by activated sludge increases to about 78 to 83%. Therefore, if this organic phosphate ester and inorganic phosphoric acid compound are used together, the utilization efficiency of the organic phosphoric acid compound is high, and the effectiveness of the inorganic phosphoric acid compound by activated sludge is also greatly improved. It has been found that the amount of phosphoric acid compounds added to the aeration tank can be significantly reduced, and the outflow of phosphorus compounds into treated water can also be greatly reduced. In addition, activated sludge treatment of ammonium water is an important process that decomposes and removes most of the COD components such as phenolic compounds and rhodan compounds.
The equipment, related principles, and operating conditions for activated sludge treatment for urban sewage are imitated exactly as they are. However, ammonium water has a more complex composition than municipal sewage, etc., and contains components such as cyanide compounds and sulfides that inhibit the function of activated sludge. , management, operational technology, etc.
There are limitations to applying it directly to ammonium water. For this reason, with conventional ammonium water activated sludge treatment, processing malfunctions of unknown cause are likely to occur, and when treatment malfunctions occur, the causes, countermeasures, and recovery techniques have not been clarified, so recovery methods have been tried only. It is a common misconception, and recovery can take a long time, from 1 to 6 months. Furthermore, an important problem when a treatment malfunction occurs is that in many cases of treatment malfunction, the decomposability of the rhodan compound decreases and the quality of the treated water deteriorates. It is difficult to remove the rhodan compounds in the treated water even by physical and chemical treatments such as iron coagulation precipitation and activated carbon adsorption, and at present, they cannot be removed economically and efficiently using methods other than activated sludge treatment. The technology to do so has not been established. Therefore, in such cases, even if additional processing equipment such as iron coagulation sedimentation method or activated carbon adsorption method is installed after activated sludge treatment, the rhodan compound cannot be removed by passing through this processing equipment. Bacteria that decompose this rodan compound (rodan assimilating bacteria) have a significantly slower growth rate than bacteria that decompose phenols, etc., and according to the research of the present inventor, the rodan assimilating bacteria are If function deteriorates, it may take some time for function to return to its pre-shock state after these shocks are removed.
It has become clear that it will take 20 to 60 days. During this period, the COD and rodan concentrations in the treated water will remain high. Another important issue is that of the amount of COD generated from steelworks, approximately 50% is due to cheap water.
This accounts for the highest ratio of ~70%, and there is a concern that malfunctions in activated sludge treatment of ammonium chloride water may occur, and that if treatment malfunctions are prolonged, it will not be possible to comply with environmental discharge regulations. Although the present inventors have already established a treatment technology suitable for treating cheap water, it has not always been possible to adequately deal with treatment failures. Therefore, the present invention has completed a technology for preventing malfunctions in the activated sludge treatment of ammonium chloride water, processing it smoothly, and maintaining the concentration of phosphorus compounds in the treated water at 1 mg/l or less. Activated sludge processing malfunctions due to shocks caused by components that inhibit the function of activated sludge in ammonium sulfate or by shocks due to abnormal PH are caused by the fact that the bacteria that make up the activated sludge are largely killed by these shocks. This is due to this. Therefore, in order to restore a normal processing state from a processing malfunction, it is first necessary to multiply the bacteria that have been reduced by the shock and restore the state to the state when normal processing was being performed. The most common method for restoring malfunctioning activated sludge to a normal state is to remove the cause of the malfunction and control the activated sludge treatment's pH, temperature, DO, etc. to appropriate conditions. However, activated sludge is an aggregate of various types of bacteria, and the properties of each type of bacteria are considered to be quite different. For example, as explained earlier, the growth rate of Rodan assimilating bacteria is extremely slow, and is about 1/2 that of bacteria that degrade phenolic compounds.
It is 40. Therefore, in order to recover from malfunctions in activated sludge treatment using ammonium water in a short period of time, it is necessary to accelerate the growth rate of bacteria that have a slow growth rate, such as rodan assimilating bacteria. Conventional methods for recovering from malfunctions simply involve controlling the activated sludge treatment conditions, such as temperature, PH, DO, etc., and hoping for the natural proliferation of bacteria. It takes a long time. Therefore, the present inventors developed bacteria, especially
We have completed a method to promote the growth of Rodan assimilating bacteria and quickly recover from processing problems, and have already applied for a patent. In other words, bacteria generally contain trace amounts of vitamins,
It is known that the presence of metal salts, enzymes, etc. accelerates the growth rate. The present inventors focused on this point, added vitamins, metal salts, enzymes, etc. to an aeration tank for ammonium activated sludge treatment, and measured the growth rate of bacteria. It was found that the proliferation rate was promoted by about 2 to 5 times compared to the case without the addition. These results suggest that when activated sludge treatment malfunctions occur, adding vitamins, enzymes, metal salts, etc. can recover the malfunction in a short period of time. Therefore, as a result of adding vitamins, metal salts, enzymes, etc. to activated sludge treatment where problems actually occurred, recovery from poor decomposition of rhodan compounds took 20 to 60 days using conventional methods. The patient recovered within 7 to 10 days. However, if this method is applied to treatment problems in actual equipment, large amounts of vitamins, enzymes, etc. are required, which poses a cost problem and is quite difficult to put into practical use. Therefore, the present inventors investigated alternatives to vitamins, enzymes, etc., and found that rice bran, wheat bran, oil residue generated during the production of vegetable oil, organic phosphoric acid compounds such as phythenic acid or its salts, or their We have already applied for a patent after discovering that the content is optimal. As a result of continued research, the present inventors have also discovered that malfunctions in activated sludge treatment can be prevented by constantly adding a small amount of the above-mentioned bacterial growth agent in combination with an inorganic phosphoric acid compound. Based on this result, the activated sludge treatment was carried out smoothly, and the concentration of phosphorus compounds in the treated water was reduced to 1mg/
As a result of considering the conditions to be maintained as follows, in the case of activated sludge treatment using ammonium water with a COD volume load of 1 to 3 kg/ m3 /day, phytic acid or water-soluble phytate per 1 m3 of aeration tank was It has been found that it is sufficient to continuously add 1 to 5 g of phosphorus and 3 to 4 g (as phosphorus) of an inorganic phosphoric acid compound. In addition, phytic acid and water-soluble phytic acid salts are considerably more expensive than inorganic phosphoric acid compounds, so as an alternative to these phytic acids,
Similar good results were obtained by using rice bran, bran, etc. that are generated when refining grains, or rice dregs that are generated when producing vegetable oil from the seeds of plants such as soybeans and sesame. This is because vegetables and plant seeds contain a considerable amount of phytic acid, and most of the phytic acid is extracted from rice bran and other sources. For example, rice bran contains about 1 to 1.5% of phosphorus, which corresponds to about 4 to 7% of phytic acid. Therefore, rice bran, wheat bran,
It is economically advantageous to use oil scum etc.
The amount added at this time is 10 to 50 per m3 of aeration tank per day.
The optimum value is approximately 100 g. Next, the concentration of phosphorus compounds in activated sludge treated water is
1mg/by adjusting the amount of inorganic phosphoric acid compound added.
The method to do this will be explained below. In the present invention, in the aeration tank for activated sludge treatment of ammonium water,
One or more of phytic acid, water-soluble phytic acid salts, and substances containing phytic acid are preferably added in predetermined amounts divided into once to three times a day. On the other hand, in the method of adding an inorganic phosphoric acid compound, the concentration of the phosphorus compound in the activated sludge treated water is measured, and it is continuously added to the feed water or the aeration tank so that the concentration is 1 g/m 3 or less. Specifically, if the concentration of phosphorus compounds in the treated water exceeds 0.5g/ m3 ,
Gradually reduce the amount of inorganic phosphoric acid compound added,
Preferably, the concentration of phosphorus compounds in the treated water is 0.2 to 0.5.
By maintaining it at g/m 3 , it can be maintained at 1 mg/m or less. On the other hand, the concentration of phosphorus compounds
If the amount is less than 0.2 g/m 3 , it is preferable to increase the amount of the inorganic phosphoric acid compound added and at the same time decrease the amount of phytic acid, phytate, or their contents. Next, the relationship between the oxidation-reduction potential (ORP) of the activated sludge settling tank of the activated sludge treatment equipment and the concentration of phosphorus compounds in the treated water will be explained. Generally, in aerobic activated sludge treatment, the aeration tank is an aerobic environment, but the activated sludge settling tank is an anaerobic environment. Aerobic activated sludge (bacteria) takes phosphorus compounds into their cells in an aerobic environment, but when these aerobic bacteria are placed in an anaerobic environment, they tend to release the phosphorus compounds they took into their cells. Therefore, when measuring phosphorus compounds in bacterial cells, the content of phosphorus compounds in the activated sludge in the aeration tank is higher than that in the activated sludge settling tank, and the longer the residence time in the settling tank, the higher the activated sludge content. The content of phosphorus compounds tends to decrease, and the concentration of phosphorus compounds in treated water tends to increase. From this, if the activated sludge settling tank is prevented from becoming anaerobic, the release of phosphorus compounds from the activated sludge can be suppressed, and the concentration of phosphorus compounds in the activated sludge treated water can be reduced. The best way to manage the anaerobic and aerobic properties of this activated sludge settling tank is to control the oxidation-reduction potential (hereinafter abbreviated as ORP). According to the research conducted by the present inventors, it was found that the ORP at which activated sludge does not release phosphorus compounds is approximately +100 to 200 mv (based on the hydrogen electrode) or more, so the ORP of the activated sludge settling tank is approximately +100 to 200 mv (based on the hydrogen electrode). +100～
It is thought that if it is maintained at 200mv or more, the release of phosphorus from activated sludge will be reduced, and the phosphorus concentration of treated water will be reduced. Generally, in aerobic activated sludge treatment, the difference in ORP between the aeration tank and the sludge settling tank is approximately 100 to 200 m.
v, and if the aeration tank is maintained in a high ORP, that is, in a more aerobic (oxidizing) environment, the ORP of the sludge settling tank will also be higher. Therefore, in the case of activated sludge treatment with cheap water, the ORP of the aeration tank should be 400 to 480 mv.
(NHE standards), the sludge settling tank
ORP can maintain conditions in which activated sludge is less likely to release phosphorus. For this reason, in activated sludge treatment with ammonium water, the ORP of the aeration tank should be controlled within the range of 400 to 480 mV, and furthermore,
If the OPR of the sludge settling tank is controlled at +100 to 200 mV or higher, activated sludge will be less likely to release phosphorus compounds. In addition to such ORP management, if activated sludge is easily used as a nutrient source by using phytic acid, water-soluble phytate, and substances containing phytic acid in combination with inorganic phosphate compounds, the process will go smoothly without causing any malfunctions. Furthermore, by controlling the amount of inorganic phosphorus compounds added, the concentration of phosphorus compounds in the treated water can be maintained at 1 mg/or less, and the process is smooth and the amount of inorganic phosphorus compounds used can be significantly reduced. This has made it possible to achieve significant reductions. Next, examples of the present invention will be described. Example 1 By conventional ammonia stripping treatment,
Ammonium water from which more than 85 to 90% of free ammonia compounds have been removed is diluted 4 times with seawater and fresh water, and the COD volumetric load is 1.5Kg/m3/ day .
While controlling the ORP of the aeration tank to +430±10mV,
Activated sludge treatment was performed by adding 30 kg (30 ppm) of rice bran to an aeration tank (3300 m 3 ) every 8 hours. If activated sludge treatment is carried out under these conditions, the sludge settling tank will
ORP will be approximately 250mV. In addition, for the inorganic phosphorus compound, phosphoric acid was added to the supplied raw water. Table 1 shows the relationship between the concentration of phosphoric acid (expressed as phosphorus) added to the feed water and the phosphorus concentration of the treated water.
【表】
表−１の結果より曝気槽に米ヌカを１日に約
30ppm添加しながら、処理水のリンを1ppm以下
にするには、供給原水にリン酸を３〜4ppm（燐と
して）添加すれば良い。この条件で長期間処理を
行つた時の処理性能を表−２に示す。[Table] From the results in Table 1, rice bran is added to the aeration tank approximately every day.
In order to reduce the phosphorus content of treated water to 1 ppm or less while adding 30 ppm, 3 to 4 ppm (as phosphorus) of phosphoric acid may be added to the feed water. Table 2 shows the processing performance when processing was performed for a long period of time under these conditions.
【表】
なお、米ヌカを添加しない従来の活性汚泥処理
は、供給原水（2000〜2200ppm）に対してリン酸
を約20ppm（リンとして）添加して処理を行うが、
この時、処理水のリン濃度は13〜17ppmである。
したがつて、本発明は、処理水のリン化合物量を
１mg／以下に維持でき、しかも無機性リン化合
物の使用量を大幅に削減することができる。
実施例 ２
実施例１の供給原水にフイチン酸を３ｇ／m3、
リン酸を３ｇ／m3添加して、安水の活性汚泥処理
を、実施例１の条件で行つた結果、活性汚泥処理
水のリン濃度は、0.3〜0.8mg／m3の範囲にあり、
また、処理水のCODは60〜80ppm、COD除去率
95％以上で、安定した、良好な処理ができること
が明らかになつた。[Table] Conventional activated sludge treatment without adding rice bran involves adding approximately 20 ppm (as phosphorus) of phosphoric acid to the raw water supply (2000 to 2200 ppm).
At this time, the phosphorus concentration of the treated water is 13 to 17 ppm.
Therefore, according to the present invention, the amount of phosphorus compounds in treated water can be maintained at 1 mg/or less, and the amount of inorganic phosphorus compounds used can be significantly reduced. Example 2 3 g/m 3 of phytic acid was added to the feed water of Example 1,
As a result of adding 3 g/m 3 of phosphoric acid and performing activated sludge treatment with ammonium water under the conditions of Example 1, the phosphorus concentration of the activated sludge treated water was in the range of 0.3 to 0.8 mg/m 3 .
In addition, the COD of treated water is 60 to 80 ppm, COD removal rate
It has become clear that stable and good processing can be achieved with a rate of 95% or higher.
Claims (1)
化合物と、フイチン酸、又は水溶性フイチン酸
塩、若しくはそれらの含有物の１種又は２種以上
を共存させ、活性汚泥処理装置の曝気槽及び沈降
槽の酸化還元電位を管理しながら活性汚泥処理を
行うとともに、処理水のリン化合物の濃度が0.5
ｇ／m3以上になつたら徐々に無機性リン酸化合物
の添加量を減少させ、一方、リン化合物の濃度が
0.2ｇ／m3以下になつたら無機性リン酸化合物の
添加量を増加させて、処理水中のリン化合物の濃
度が１mg／以下になるように調整することを特
徴とする安水の活性汚泥処理方法。1. An inorganic phosphoric acid compound and phytic acid, water-soluble phytate, or one or more of these substances are allowed to coexist in an aeration tank for activated sludge treatment of ammonium water, and aeration of activated sludge treatment equipment is carried out. Activated sludge treatment is performed while controlling the redox potential of the tank and sedimentation tank, and the concentration of phosphorus compounds in the treated water is 0.5.
g/ m3 or more, gradually reduce the amount of inorganic phosphoric acid compound added, while increasing the concentration of phosphorus compound.
Activated sludge treatment of ammonium water, characterized in that when the concentration of phosphorus compounds in treated water becomes 0.2 g/ m3 or less, the amount of inorganic phosphoric acid compounds added is increased to adjust the concentration of phosphorus compounds in the treated water to 1 mg/m3 or less. Method.
Priority Applications (8)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP58051840A JPS59177195A (en) | 1983-03-28 | 1983-03-28 | Treatment of ammonia liquor with activated sludge |
| FR838307942A FR2527585B1 (en) | 1982-05-13 | 1983-05-11 | PROCESS FOR THE TREATMENT OF INDUSTRIAL WASTEWATER WITH ACTIVATED SLUDGE |
| IT4827183A IT1173711B (en) | 1982-05-13 | 1983-05-11 | PROCEDURE FOR TREATING WASTE WATER FROM INDUSTRIAL PLANTS WITH ACTIVE MUD |
| CA000427980A CA1197633A (en) | 1982-05-13 | 1983-05-12 | Process for treating industrial wastewaters by activated sludge |
| GB08313090A GB2121398B (en) | 1982-05-13 | 1983-05-12 | Process for treating industrial wastewaters by avtivated sludge |
| AU14528/83A AU548300B2 (en) | 1982-05-13 | 1983-05-13 | Treating industrial waste waters by activated sludge |
| DE3317577A DE3317577C2 (en) | 1982-05-13 | 1983-05-13 | Process for the activated sludge treatment of waste water |
| US06/902,069 US4698158A (en) | 1982-05-13 | 1986-08-27 | Process for treating industrial wastewaters by activated sludge |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP58051840A JPS59177195A (en) | 1983-03-28 | 1983-03-28 | Treatment of ammonia liquor with activated sludge |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS59177195A JPS59177195A (en) | 1984-10-06 |
| JPS6345635B2 true JPS6345635B2 (en) | 1988-09-09 |
Family
ID=12898050
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP58051840A Granted JPS59177195A (en) | 1982-05-13 | 1983-03-28 | Treatment of ammonia liquor with activated sludge |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS59177195A (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP5103796B2 (en) * | 2006-06-09 | 2012-12-19 | 栗田工業株式会社 | Biological treatment accelerator for wastewater and biological treatment method for wastewater using the same |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5779123A (en) * | 1980-10-31 | 1982-05-18 | Kawasaki Steel Corp | Continuous annealing method for cold rolled steel strip and its device |
-
1983
- 1983-03-28 JP JP58051840A patent/JPS59177195A/en active Granted
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5779123A (en) * | 1980-10-31 | 1982-05-18 | Kawasaki Steel Corp | Continuous annealing method for cold rolled steel strip and its device |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS59177195A (en) | 1984-10-06 |
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