JP2003033797A - Deodorant for sludge dehydrate cake and deodorizing method - Google Patents
Deodorant for sludge dehydrate cake and deodorizing methodInfo
- Publication number
- JP2003033797A JP2003033797A JP2001222887A JP2001222887A JP2003033797A JP 2003033797 A JP2003033797 A JP 2003033797A JP 2001222887 A JP2001222887 A JP 2001222887A JP 2001222887 A JP2001222887 A JP 2001222887A JP 2003033797 A JP2003033797 A JP 2003033797A
- Authority
- JP
- Japan
- Prior art keywords
- sludge
- deodorant
- nitrite
- cake
- deodorizing
- 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.)
- Granted
Links
- 239000010802 sludge Substances 0.000 title claims abstract description 78
- 239000002781 deodorant agent Substances 0.000 title claims abstract description 57
- 230000001877 deodorizing effect Effects 0.000 title claims abstract description 33
- 238000000034 method Methods 0.000 title claims abstract description 14
- IOVCWXUNBOPUCH-UHFFFAOYSA-M Nitrite anion Chemical compound [O-]N=O IOVCWXUNBOPUCH-UHFFFAOYSA-M 0.000 claims abstract description 21
- 229910001385 heavy metal Inorganic materials 0.000 claims abstract description 14
- ZAMOUSCENKQFHK-UHFFFAOYSA-N Chlorine atom Chemical compound [Cl] ZAMOUSCENKQFHK-UHFFFAOYSA-N 0.000 claims abstract description 9
- 239000000460 chlorine Substances 0.000 claims abstract description 9
- 229910052801 chlorine Inorganic materials 0.000 claims abstract description 9
- 239000000725 suspension Substances 0.000 claims abstract description 8
- 239000003112 inhibitor Substances 0.000 claims description 27
- LSDPWZHWYPCBBB-UHFFFAOYSA-N Methanethiol Chemical compound SC LSDPWZHWYPCBBB-UHFFFAOYSA-N 0.000 claims description 20
- RWSOTUBLDIXVET-UHFFFAOYSA-N Dihydrogen sulfide Chemical compound S RWSOTUBLDIXVET-UHFFFAOYSA-N 0.000 claims description 8
- 239000000243 solution Substances 0.000 claims description 8
- 229910000037 hydrogen sulfide Inorganic materials 0.000 claims description 7
- 239000007864 aqueous solution Substances 0.000 claims description 6
- 239000003381 stabilizer Substances 0.000 claims description 4
- 230000008719 thickening Effects 0.000 claims description 4
- 238000013329 compounding Methods 0.000 abstract description 2
- 230000002688 persistence Effects 0.000 abstract 1
- LPXPTNMVRIOKMN-UHFFFAOYSA-M sodium nitrite Chemical compound [Na+].[O-]N=O LPXPTNMVRIOKMN-UHFFFAOYSA-M 0.000 description 20
- 230000000052 comparative effect Effects 0.000 description 11
- 235000010288 sodium nitrite Nutrition 0.000 description 10
- 230000018044 dehydration Effects 0.000 description 9
- 238000006297 dehydration reaction Methods 0.000 description 9
- -1 H 2 S and mercaptan Chemical class 0.000 description 7
- 239000004698 Polyethylene Substances 0.000 description 6
- 239000003795 chemical substances by application Substances 0.000 description 6
- 238000004332 deodorization Methods 0.000 description 6
- 229920000573 polyethylene Polymers 0.000 description 6
- 150000003839 salts Chemical class 0.000 description 5
- 239000010865 sewage Substances 0.000 description 5
- 229940043810 zinc pyrithione Drugs 0.000 description 5
- PICXIOQBANWBIZ-UHFFFAOYSA-N zinc;1-oxidopyridine-2-thione Chemical compound [Zn+2].[O-]N1C=CC=CC1=S.[O-]N1C=CC=CC1=S PICXIOQBANWBIZ-UHFFFAOYSA-N 0.000 description 5
- 230000000694 effects Effects 0.000 description 4
- 238000003756 stirring Methods 0.000 description 4
- 239000000701 coagulant Substances 0.000 description 3
- 230000007774 longterm Effects 0.000 description 3
- 150000002826 nitrites Chemical class 0.000 description 3
- 229920000642 polymer Polymers 0.000 description 3
- DPBJAVGHACCNRL-UHFFFAOYSA-N 2-(dimethylamino)ethyl prop-2-enoate Chemical compound CN(C)CCOC(=O)C=C DPBJAVGHACCNRL-UHFFFAOYSA-N 0.000 description 2
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 description 2
- SIKJAQJRHWYJAI-UHFFFAOYSA-N Indole Chemical compound C1=CC=C2NC=CC2=C1 SIKJAQJRHWYJAI-UHFFFAOYSA-N 0.000 description 2
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical group [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- 230000000844 anti-bacterial effect Effects 0.000 description 2
- 239000003899 bactericide agent Substances 0.000 description 2
- DMSMPAJRVJJAGA-UHFFFAOYSA-N benzo[d]isothiazol-3-one Chemical compound C1=CC=C2C(=O)NSC2=C1 DMSMPAJRVJJAGA-UHFFFAOYSA-N 0.000 description 2
- 238000007789 sealing Methods 0.000 description 2
- ZFRKQXVRDFCRJG-UHFFFAOYSA-N skatole Chemical compound C1=CC=C2C(C)=CNC2=C1 ZFRKQXVRDFCRJG-UHFFFAOYSA-N 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 239000000230 xanthan gum Substances 0.000 description 2
- 229920001285 xanthan gum Polymers 0.000 description 2
- 235000010493 xanthan gum Nutrition 0.000 description 2
- 229940082509 xanthan gum Drugs 0.000 description 2
- JKNCOURZONDCGV-UHFFFAOYSA-N 2-(dimethylamino)ethyl 2-methylprop-2-enoate Chemical compound CN(C)CCOC(=O)C(C)=C JKNCOURZONDCGV-UHFFFAOYSA-N 0.000 description 1
- HRPVXLWXLXDGHG-UHFFFAOYSA-N Acrylamide Chemical group NC(=O)C=C HRPVXLWXLXDGHG-UHFFFAOYSA-N 0.000 description 1
- OYPRJOBELJOOCE-UHFFFAOYSA-N Calcium Chemical compound [Ca] OYPRJOBELJOOCE-UHFFFAOYSA-N 0.000 description 1
- 229920002134 Carboxymethyl cellulose Polymers 0.000 description 1
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- 229920002907 Guar gum Polymers 0.000 description 1
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 description 1
- 239000004677 Nylon Substances 0.000 description 1
- 239000004372 Polyvinyl alcohol Substances 0.000 description 1
- BQCADISMDOOEFD-UHFFFAOYSA-N Silver Chemical compound [Ag] BQCADISMDOOEFD-UHFFFAOYSA-N 0.000 description 1
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 description 1
- AZFNGPAYDKGCRB-XCPIVNJJSA-M [(1s,2s)-2-amino-1,2-diphenylethyl]-(4-methylphenyl)sulfonylazanide;chlororuthenium(1+);1-methyl-4-propan-2-ylbenzene Chemical compound [Ru+]Cl.CC(C)C1=CC=C(C)C=C1.C1=CC(C)=CC=C1S(=O)(=O)[N-][C@@H](C=1C=CC=CC=1)[C@@H](N)C1=CC=CC=C1 AZFNGPAYDKGCRB-XCPIVNJJSA-M 0.000 description 1
- 229910021529 ammonia Inorganic materials 0.000 description 1
- CAMXVZOXBADHNJ-UHFFFAOYSA-N ammonium nitrite Chemical compound [NH4+].[O-]N=O CAMXVZOXBADHNJ-UHFFFAOYSA-N 0.000 description 1
- 239000011575 calcium Substances 0.000 description 1
- 229910052791 calcium Inorganic materials 0.000 description 1
- 239000001768 carboxy methyl cellulose Substances 0.000 description 1
- 235000010948 carboxy methyl cellulose Nutrition 0.000 description 1
- 239000008112 carboxymethyl-cellulose Substances 0.000 description 1
- 229940105329 carboxymethylcellulose Drugs 0.000 description 1
- 239000004568 cement Substances 0.000 description 1
- 230000002301 combined effect Effects 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 229920001577 copolymer Polymers 0.000 description 1
- 229910052802 copper Inorganic materials 0.000 description 1
- 239000010949 copper Substances 0.000 description 1
- 239000010840 domestic wastewater Substances 0.000 description 1
- 239000004744 fabric Substances 0.000 description 1
- 239000003337 fertilizer Substances 0.000 description 1
- 239000000665 guar gum Substances 0.000 description 1
- 235000010417 guar gum Nutrition 0.000 description 1
- 229960002154 guar gum Drugs 0.000 description 1
- 239000010800 human waste Substances 0.000 description 1
- PZOUSPYUWWUPPK-UHFFFAOYSA-N indole Natural products CC1=CC=CC2=C1C=CN2 PZOUSPYUWWUPPK-UHFFFAOYSA-N 0.000 description 1
- RKJUIXBNRJVNHR-UHFFFAOYSA-N indolenine Natural products C1=CC=C2CC=NC2=C1 RKJUIXBNRJVNHR-UHFFFAOYSA-N 0.000 description 1
- 239000010842 industrial wastewater Substances 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 230000005923 long-lasting effect Effects 0.000 description 1
- 239000011777 magnesium Substances 0.000 description 1
- 229910052749 magnesium Inorganic materials 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 229920001778 nylon Polymers 0.000 description 1
- 239000001814 pectin Substances 0.000 description 1
- 229920001277 pectin Polymers 0.000 description 1
- 235000010987 pectin Nutrition 0.000 description 1
- 229960000292 pectin Drugs 0.000 description 1
- 229920002451 polyvinyl alcohol Polymers 0.000 description 1
- 229940068984 polyvinyl alcohol Drugs 0.000 description 1
- 235000019422 polyvinyl alcohol Nutrition 0.000 description 1
- 235000010289 potassium nitrite Nutrition 0.000 description 1
- 239000004304 potassium nitrite Substances 0.000 description 1
- YBBJKCMMCRQZMA-UHFFFAOYSA-N pyrithione Chemical class ON1C=CC=CC1=S YBBJKCMMCRQZMA-UHFFFAOYSA-N 0.000 description 1
- 229910052709 silver Inorganic materials 0.000 description 1
- 239000004332 silver Substances 0.000 description 1
- 229940074386 skatole Drugs 0.000 description 1
- XNRNJIIJLOFJEK-UHFFFAOYSA-N sodium;1-oxidopyridine-2-thione Chemical compound [Na+].[O-]N1C=CC=CC1=S XNRNJIIJLOFJEK-UHFFFAOYSA-N 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 150000003464 sulfur compounds Chemical class 0.000 description 1
- 238000004065 wastewater treatment Methods 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
- 229910052725 zinc Inorganic materials 0.000 description 1
- 239000011701 zinc Substances 0.000 description 1
Landscapes
- Treatment Of Sludge (AREA)
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は、汚泥脱水ケーキ用
脱臭剤および脱臭方法に関する。さらに詳しくは、廃水
処理などで生じる汚泥の脱水ケーキの異臭を防止するた
めに用いる脱臭剤、および該脱臭剤を用いる汚泥脱水ケ
ーキの脱臭方法に関する。TECHNICAL FIELD The present invention relates to a deodorant for a sludge dewatering cake and a deodorizing method. More specifically, the present invention relates to a deodorizing agent used for preventing an offensive odor of a dehydrated cake of sludge caused by wastewater treatment and the like, and a deodorizing method of a sludge dehydrated cake using the deodorant.
【０００２】[0002]
【従来の技術】従来、汚泥脱水ケーキの脱臭剤として、
亜硝酸塩を単独で、または亜硝酸塩とピリチオン塩とを
組み合わせて用いることが知られている（特開２０００
−２８８５９２）。これらの脱臭剤は、短期間の脱臭に
は有効であったが、たとえば４〜５日以上という長期間
脱臭効果を維持しようとする場合には不充分であった。
そのため、汚泥脱水ケーキを最終的に処理するまでに長
期間を要すると、異臭が発生する場合があった。したが
って、従来から、汚泥脱水ケーキの脱臭効果を、少しで
も長く持続させたいという課題があり、そのような脱臭
効果を達成できる脱臭剤が切に望まれていた。Conventionally, as a deodorant for sludge dewatering cake,
It is known to use nitrites alone or in combination with nitrites and pyrithione salts (JP 2000
-288592). Although these deodorants were effective for short-term deodorization, they were insufficient for maintaining a long-term deodorization effect of, for example, 4 to 5 days or longer.
Therefore, if it takes a long time to finally treat the sludge dewatering cake, an offensive odor may be generated. Therefore, there has been a problem in the past that the deodorizing effect of the sludge dewatering cake should be maintained as long as possible, and a deodorant capable of achieving such a deodorizing effect has been earnestly desired.
【０００３】また、特開２０００−２８８５９２のよう
に脱臭剤としてジンクピリチオンなどの重金属塩を用い
ると、汚泥脱水ケーキに重金属が混入して再利用が困難
になるので、好ましくない。さらに、特開２０００−２
８８５９２では、亜硝酸塩と他の薬剤とを、二液型とし
て、別個に汚泥に添加するので、ストックタンクおよび
ポンプが２つ必要となり、また２品種の薬品を投入する
ことになり、さらに添加量の制御が困難であるというデ
メリットがあり、脱臭作業の現場では一液型の脱臭剤が
望まれていた。Also, when a heavy metal salt such as zinc pyrithione is used as a deodorant as in JP-A-2000-288592, it is not preferable because heavy metal is mixed in the sludge dehydrated cake and reuse becomes difficult. Furthermore, JP 2000-2
In 88592, nitrite and other chemicals are separately added to the sludge as a two-pack type, so two stock tanks and pumps are required, and two types of chemicals must be added. However, there is a demerit that it is difficult to control, and a one-pack type deodorant was desired at the site of deodorizing work.
【０００４】[0004]
【発明が解決しようとする課題】本発明の目的は、操作
が簡便であり、脱臭効果が長期間持続する一液型の汚泥
脱水ケーキ用脱臭剤、および、汚泥脱水ケーキの脱臭方
法を提供することにある。DISCLOSURE OF THE INVENTION An object of the present invention is to provide a one-component type deodorant for sludge dewatering cake, which is easy to operate and has a long-lasting deodorizing effect, and a method for deodorizing a sludge dewatering cake. Especially.
【０００５】[0005]
【課題を解決するための手段】前記実情に鑑み、鋭意研
究の結果、脱臭剤として、亜硝酸塩水溶液と重金属およ
び塩素を含まない腐敗抑制剤とを一液型の懸濁液として
用いることによって、前記課題を解決できることを見出
し、本発明に到達した。[Means for Solving the Problems] In view of the above circumstances, as a result of earnest research, as a deodorant, an aqueous nitrite solution and a decay inhibitor containing neither heavy metal nor chlorine are used as a one-component suspension, The inventors have found that the above problems can be solved and arrived at the present invention.
【０００６】すなわち、本発明は、
亜硝酸塩水溶液と重金属および塩素を含有しない腐
敗抑制剤とを配合した懸濁液からなることを特徴とする
一液型の汚泥脱水ケーキ用脱臭剤、の亜硝酸塩との
腐敗抑制剤との割合が２：１〜８０：１（重量比）であ
る前記脱臭剤、亜硝酸塩水溶液の濃度が４重量％以上で
ある前記各脱臭剤、腐敗抑制剤が２，２’−ジチオビス
−ピリジン−１，１’−ジオキシドである前記各脱臭
剤、さらに増粘安定剤を含有する前記各脱臭剤、前記各
脱臭剤を汚泥に添加したのち、脱水することを特徴とす
る汚泥脱水ケーキの脱臭方法、および前記各脱臭剤を汚
泥に添加したのち、汚泥から発生する硫化水素およびメ
チルメルカプタンの各々の濃度が、脱臭剤添加前の汚泥
から発生する硫化水素およびメチルメルカプタンの各々
の濃度の５０％以下となったのち、脱水することを特徴
とする汚泥脱水ケーキの脱臭方法に関する。That is, the present invention relates to a nitrite salt of a one-pack type deodorant for a sludge dewatering cake, which comprises a suspension containing an aqueous nitrite solution and a decay inhibitor containing no heavy metals and chlorine. The deodorant having a ratio of 2: 1 to 80: 1 (weight ratio) to the putrefaction inhibitor, the deodorant having the concentration of the aqueous nitrite solution of 4% by weight or more, and the putrefaction inhibitor are 2,2. The above-mentioned deodorizing agent which is'-dithiobis-pyridine-1,1'-dioxide, each deodorizing agent containing a thickening stabilizer, and each deodorizing agent are added to sludge and then dehydrated. Deodorizing method of sludge dewatering cake, and after adding each deodorant to the sludge, the respective concentrations of hydrogen sulfide and methyl mercaptan generated from the sludge, hydrogen sulfide and methyl mercaptan of the sludge generated before the addition of the deodorant After a 50% or less of the concentration of people, to deodorization process sludge dewatering cake, characterized in that the dehydration.
【０００７】本発明において、脱臭とは、すでに発生し
ている悪臭を除去すること、および、放置しておけば発
生するであろう悪臭を発生しないようにすることの両方
を含む概念である。In the present invention, the deodorization is a concept that includes both removing the malodor that has already occurred and preventing the malodor that would occur if left unattended.
【０００８】[0008]
【発明の実施の形態】本発明の汚泥脱水ケーキ用脱臭剤
は、亜硝酸塩水溶液と重金属および塩素を含有しな
い腐敗抑制剤とを配合した懸濁液からなり、一液型であ
ることを特徴とする。BEST MODE FOR CARRYING OUT THE INVENTION The deodorant for sludge dewatering cake of the present invention comprises a suspension prepared by mixing an aqueous nitrite solution and a decay inhibitor containing no heavy metal and chlorine, and is a one-pack type. To do.
【０００９】亜硝酸塩を含有し、腐敗抑制剤を含有しな
い汚泥用脱臭剤でも、脱臭効果を得ることはできるが、
腐敗抑制剤を併用することにより、脱臭効果がさらに向
上する。逆に、腐敗抑制剤を含有し、亜硝酸塩を含有し
ない汚泥用脱臭剤では、添加直後の脱臭効果が小さく、
即効性に劣る。亜硝酸塩と腐敗抑制剤とを予め配合しな
い場合、前記したように設備上の問題や操作が煩雑にな
るという問題がある。A deodorizing agent for sludge which contains nitrite and does not contain a spoilage inhibitor can obtain the deodorizing effect,
The deodorizing effect is further improved by using the decay inhibitor together. On the contrary, a deodorant for sludge containing a putrefaction inhibitor and containing no nitrite has a small deodorizing effect immediately after addition,
Inferior immediate effect. If the nitrite and the putrefaction inhibitor are not blended in advance, there is a problem in that the facility and the operation become complicated as described above.
【００１０】亜硝酸塩としては、とくに限定されない
が、たとえば、亜硝酸アンモニウム、亜硝酸ナトリウ
ム、亜硝酸カリウムを挙げることができ、亜硝酸ナトリ
ウムが好ましい。亜硝酸塩水溶液の濃度は、腐敗抑制剤
を懸濁させるために、４重量％以上、さらには１０〜４
０重量％とすることが好ましい。The nitrite is not particularly limited, but examples thereof include ammonium nitrite, sodium nitrite and potassium nitrite, and sodium nitrite is preferable. The concentration of the nitrite aqueous solution is 4% by weight or more, further 10 to 4% in order to suspend the putrefaction inhibitor.
It is preferably 0% by weight.
【００１１】腐敗抑制剤は、殺菌剤として作用する化合
物である。腐敗抑制剤としては、重金属および塩素を含
有しない一般的な工業用殺菌剤を使用することができ
る。ここでいう重金属とは、鉄、亜鉛、カルシウム、マ
グネシウム、銅、銀などである。重金属および塩素を含
有しない腐敗抑制剤としては、２，２’−ジチオビス−
ピリジン−１，１’−ジオキシド（ＯＤＳ）や１，２−
ベンズイソチアゾリン−３−オン（ＢＩＴ）などを挙げ
ることができ、より少ない量で有効である点からＯＤＳ
が好ましい。[0011] A putrefaction inhibitor is a compound that acts as a bactericide. As the decay inhibitor, a general industrial bactericide containing neither heavy metal nor chlorine can be used. The heavy metal mentioned here is iron, zinc, calcium, magnesium, copper, silver or the like. As a decay inhibitor containing neither heavy metal nor chlorine, 2,2′-dithiobis-
Pyridine-1,1'-dioxide (ODS) and 1,2-
Benzisothiazolin-3-one (BIT) and the like can be mentioned, and ODS is effective in a smaller amount.
Is preferred.
【００１２】本発明の脱臭剤における亜硝酸塩と腐敗抑
制剤との配合比（重量比）は、２：１〜８０：１、さら
には１０：１〜５０：１であることが好ましい。The compounding ratio (weight ratio) of the nitrite and the decay inhibitor in the deodorant of the present invention is preferably 2: 1 to 80: 1, more preferably 10: 1 to 50: 1.
【００１３】本発明の脱臭剤には、製品安定性を向上す
るために、必要に応じて、キサンタンガム、グアーガ
ム、ペクチン、カルボキシメチルセルロース、ポリビニ
ルアルコールなどの増粘安定剤を配合することができ
る。増粘安定剤の配合量は、たとえば、０．０１〜１．
０重量％配合することができる。In order to improve the product stability, the deodorant of the present invention may contain a thickening stabilizer such as xanthan gum, guar gum, pectin, carboxymethyl cellulose and polyvinyl alcohol, if necessary. The content of the thickening stabilizer is, for example, 0.01-1.
0 wt% can be blended.
【００１４】本発明の脱臭剤は、下水、各種工場廃水、
家庭廃水、し尿などの処理の際に発生する汚泥の脱水ケ
ーキの脱臭処理に有効である。本発明の脱臭剤は、硫化
水素（Ｈ2Ｓ）、メルカプタン、アンモニア、インドー
ル、スカトールなどの悪臭成分、とくにＨ2Ｓ、メルカ
プタンなどの硫黄系化合物が、汚泥脱水ケーキから発生
することを有効に防止することができる。The deodorant of the present invention is used for sewage, various industrial wastewater,
It is effective for deodorizing the dehydrated cake of sludge generated during the treatment of domestic wastewater and human waste. The deodorant of the present invention effectively produces malodorous components such as hydrogen sulfide (H 2 S), mercaptan, ammonia, indole, and skatole, particularly sulfur compounds such as H 2 S and mercaptan, from a sludge dehydrated cake. Can be prevented.
【００１５】本発明の脱臭剤、すなわち、亜硝酸塩水
溶液と重金属および塩素を含有しない腐敗抑制剤とを
予め配合した懸濁液を、脱水前の汚泥または汚泥脱水ケ
ーキ（脱水後の汚泥）に添加し、必要に応じて攪拌する
ことにより、汚泥や汚泥脱水ケーキからの悪臭の発生を
防止することができる。脱臭剤は、脱水後の汚泥脱水ケ
ーキに添加してもよいが、亜硝酸塩と腐敗抑制剤とを汚
泥脱水ケーキに均一に混合できる点で、脱水前の汚泥に
添加することが好ましい。The deodorant of the present invention, that is, a suspension in which an aqueous nitrite solution and a spoilage inhibitor containing no heavy metals and chlorine are mixed in advance is added to sludge before dehydration or sludge dehydration cake (sludge after dehydration). However, by stirring as necessary, it is possible to prevent the generation of offensive odor from the sludge and the sludge dewatering cake. The deodorant may be added to the sludge dewatering cake after dehydration, but it is preferable to add it to the sludge before dewatering because the nitrite and the putrefaction inhibitor can be uniformly mixed in the sludge dewatering cake.
【００１６】とくに脱臭剤添加後、汚泥から発生する悪
臭成分（硫化水素およびメチルメルカプタン）の濃度
が、添加前の汚泥から発生する悪臭成分の濃度の５０％
以下（脱臭率で５０％以上）、好ましくは０〜４０％に
なったのちに脱水するほうが脱臭効果の持続性の点で好
ましい。汚泥から発生する悪臭成分の濃度は、たとえ
ば、所定容量の密閉容器に、所定量の汚泥を入れ、容器
内の汚泥に脱臭剤を添加、混合し、密閉後、所定時間経
過したのち、ヘッドスペース部の悪臭成分の濃度を検知
管で測定することによって、特定することができる。脱
臭剤添加前の汚泥から発生する悪臭成分の濃度は、脱臭
剤を添加、混合することなく、同様の処理をすることに
よって、特定することができる。Particularly, the concentration of malodorous components (hydrogen sulfide and methyl mercaptan) generated from the sludge after addition of the deodorant is 50% of the concentration of malodorous components generated from the sludge before addition.
It is preferable that the deodorization rate is 50% or more, preferably 0 to 40%, and then dehydrated after the deodorizing effect is maintained. The concentration of the malodorous component generated from the sludge is determined by, for example, putting a predetermined amount of sludge in a closed container having a predetermined volume, adding a deodorant to the sludge in the container, mixing and sealing, and after a predetermined time has passed, headspace It can be specified by measuring the concentration of the malodorous component in the part with a detector tube. The concentration of the malodorous component generated from the sludge before the addition of the deodorant can be specified by performing the same treatment without adding and mixing the deodorant.
【００１７】脱臭剤を脱水前の汚泥に添加する場合の脱
臭剤の添加量は、たとえば、汚泥１リットルに対して、
亜硝酸塩が４０〜１０００ｍｇ、とくに８０〜３００ｍ
ｇとなるようにすることが好ましい。汚泥１リットルに
対して４０ｍｇ未満では脱臭効果が劣る傾向があり、１
０００ｍｇをこえるとランニングコストが高まるわりに
脱臭効果が向上しない傾向がある。When the deodorant is added to the sludge before dehydration, the amount of the deodorant added is, for example, 1 liter of sludge.
40 to 1000 mg of nitrite, especially 80 to 300 m
It is preferable that it is g. If it is less than 40 mg per 1 liter of sludge, the deodorizing effect tends to be poor.
If it exceeds 000 mg, the deodorizing effect tends not to improve although the running cost increases.
【００１８】また、脱臭剤を脱水前の汚泥に添加する場
合の脱臭剤の添加量は、たとえば、汚泥１リットルに対
して、腐敗抑制剤が１〜１００ｍｇ、とくに５〜５０ｍ
ｇとなるようにすることが好ましい。汚泥１リットルに
対して１ｍｇ未満では持続的に脱臭効果を発現すること
が困難になる傾向があり、１００ｍｇをこえると持続的
に脱臭効果を発現することはできるが、ランニングコス
トが高まり経済性に劣る傾向がある。When the deodorant is added to the sludge before dehydration, the amount of the deodorant added is, for example, 1 to 100 mg, particularly 5 to 50 m of the decay inhibitor per 1 liter of sludge.
It is preferable that it is g. If it is less than 1 mg per 1 liter of sludge, it tends to be difficult to exert a deodorizing effect continuously, and if it exceeds 100 mg, a deodorizing effect can be exerted continuously, but running cost increases and it is economical. Tends to be inferior.
【００１９】本発明の脱臭剤は、亜硝酸塩水溶液と腐敗
抑制剤とを配合した一液型脱臭剤であるので、ダイヤフ
ラム式、プランジャー式の定量ポンプなどを用いて供給
することによって、脱水前の汚泥に添加することができ
る。Since the deodorant of the present invention is a one-pack type deodorant containing an aqueous nitrite solution and a putrefaction inhibitor, it can be supplied by using a diaphragm type or plunger type metering pump or the like to prevent dewatering. Can be added to the sludge.
【００２０】脱臭剤を脱水前の汚泥に添加する場合、脱
臭を効率的に行なうために、亜硝酸塩と腐敗抑制剤との
一液型脱臭剤を添加する際、攪拌することが好ましい。
攪拌は、汚泥と脱臭剤とを混合できる方法であればいず
れの方法であってもよく、たとえば、攪拌翼、インライ
ンミキサーなどによって実施することができる。When the deodorant is added to the sludge before dehydration, it is preferable to stir when adding the one-pack type deodorant of the nitrite and the putrefaction inhibitor in order to efficiently perform the deodorization.
The stirring may be performed by any method as long as the sludge and the deodorant can be mixed, and can be carried out, for example, by a stirring blade or an in-line mixer.
【００２１】汚泥の脱水手段については、とくに制限は
なく、当業者に公知の手段により適宜実施することがで
きる。汚泥を脱水する際には凝集剤を添加することがで
きる。凝集剤としては、たとえば、ジメチルアミノエチ
ルアクリレート４級塩の重合体、ジメチルアミノエチル
メタクリレート４級塩の重合体、これらの４級塩とアク
リルアミドとの共重合体、ポリアミジンなどを使用する
ことができる。The sludge dewatering means is not particularly limited and can be appropriately implemented by means known to those skilled in the art. A coagulant can be added when dewatering sludge. As the coagulant, for example, a polymer of quaternary salt of dimethylaminoethyl acrylate, a polymer of quaternary salt of dimethylaminoethyl methacrylate, a copolymer of these quaternary salt and acrylamide, polyamidine and the like can be used. .
【００２２】本発明の脱臭剤によって脱臭した汚泥脱水
ケーキは、重金属または塩素を含まないので、セメント
の骨材や肥料などとして良好に再利用することができ
る。Since the sludge dewatering cake deodorized by the deodorant of the present invention does not contain heavy metals or chlorine, it can be favorably reused as cement aggregate or fertilizer.
【００２３】[0023]
【実施例】以下、実施例に基づき本発明をさらに詳細に
説明する。The present invention will be described in more detail based on the following examples.
【００２４】実施例１〜３および比較例１〜４
水５８重量部にキサンタンガム０．２重量部を加え溶解
させたのち、亜硝酸ソーダ４０重量部を加え溶解させ
る。つぎにＯＤＳ２重量部を加え懸濁液を得た。Examples 1 to 3 and Comparative Examples 1 to 4 0.2 parts by weight of xanthan gum was added to and dissolved in 58 parts by weight of water, and then 40 parts by weight of sodium nitrite was added and dissolved therein. Next, 2 parts by weight of ODS was added to obtain a suspension.
【００２５】１リットルのポリエチレン瓶に、公共下水
処理場Ａにて採取した汚泥５００ｃｃを分取し、分取し
た汚泥に、前記脱臭剤を、亜硝酸ソーダおよびＯＤＳの
添加量が表１に示す量となるように添加、混合し、密閉
した。ポリエチレン瓶のヘッドスペース部の悪臭成分
（Ｈ2Ｓ、メチルメルカプタン（ＭＭ））の濃度を、検
知管（ガステック社製）で測定した。500 cc of sludge collected at the public sewage treatment plant A was dispensed into a 1-liter polyethylene bottle, and the amount of the deodorant, sodium nitrite and ODS added to the dispensed sludge is shown in Table 1. The amount was added, mixed, and sealed. The concentration of the malodorous components (H 2 S, methyl mercaptan (MM)) in the head space of the polyethylene bottle was measured with a detector tube (manufactured by Gastec).
【００２６】悪臭成分の濃度が無添加時に比べ５０％以
下となったのち、ポリエチレン瓶内の混合物（脱臭剤を
添加した汚泥）の２００ｃｃをビーカーにとり、凝集剤
としてジメチルアミノエチルアクリレート４級塩の重合
体（第一工業製薬（株）製のハイセットＣ２００Ｈ）を
添加し、撹拌して凝集物を得た。得られた凝集物を２０
０メッシュのナイロン濾布を敷いたヌッチェで濾過し、
固形物を加圧プレスにかけて汚泥脱水ケーキを得た。汚
泥脱水ケーキを２５０ｃｃのポリエチレン瓶に入れ、密
閉し、１、２、３および４日後に悪臭成分の濃度を測定
した。結果を表１に示す。After the concentration of the malodorous component became 50% or less as compared with that without addition, 200 cc of the mixture in the polyethylene bottle (sludge to which the deodorant was added) was placed in a beaker and dimethylaminoethyl acrylate quaternary salt was used as a coagulant. A polymer (Hi-Set C200H manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.) was added and stirred to obtain an aggregate. 20 agglomerates obtained
Filter with a nutche lined with 0 mesh nylon filter cloth,
The solid matter was subjected to a pressure press to obtain a sludge dewatering cake. The sludge dewatering cake was put into a 250 cc polyethylene bottle, sealed, and the concentration of the malodorous component was measured after 1, 2, 3 and 4 days. The results are shown in Table 1.
【００２７】比較例１
脱臭剤を使用しなかったほかは、実施例１〜３と同様に
して、悪臭成分の濃度を測定した。結果を表１に示す。Comparative Example 1 The concentrations of malodorous components were measured in the same manner as in Examples 1 to 3 except that no deodorant was used. The results are shown in Table 1.
【００２８】比較例２
脱臭剤として亜硝酸ソーダ水溶液を単独で使用したほか
は、実施例１〜３と同様にして、悪臭成分の濃度を測定
した。結果を表１に示す。Comparative Example 2 The concentrations of malodorous components were measured in the same manner as in Examples 1 to 3 except that an aqueous sodium nitrite solution was used alone as the deodorant. The results are shown in Table 1.
【００２９】比較例３および４
脱臭剤としてＯＤＳを単独で使用したほかは、実施例１
〜３と同様にして、悪臭成分の濃度を測定した。結果を
表１に示す。Comparative Examples 3 and 4 Example 1 except that ODS was used alone as the deodorant.
The concentration of the malodorous component was measured in the same manner as in Steps 3 to 3. The results are shown in Table 1.
【００３０】比較例５〜８
ポリエチレン瓶に分取した汚泥に４０重量％の亜硝酸ソ
ーダ水溶液を添加、混合し、密閉し、さらに腐敗抑制剤
としてジンクピリチオン（ＺＰＴ）またはナトリウムピ
リチオン（ＮａＰＴ）を添加、混合し、密閉し、ポリエ
チレン瓶のヘッドスペース部における悪臭成分の濃度を
測定し、無添加に比べ硫化水素およびメチルメルカプタ
ンの各々の濃度が５０％以下になったのち、脱水したほ
かは、実施例１〜３と同様にして、悪臭成分の濃度を測
定した。結果を表１に示す。Comparative Examples 5 to 8 A 40% by weight aqueous solution of sodium nitrite was added to a sludge collected in a polyethylene bottle, mixed and sealed, and zinc pyrithione (ZPT) or sodium pyrithione (NaPT) was added as a decay inhibitor. , Mixing and sealing, measuring the concentration of malodorous components in the head space of the polyethylene bottle, and after dehydration after the concentration of each of hydrogen sulfide and methyl mercaptan became 50% or less compared to the case of no addition, it was carried out. The concentration of the malodorous component was measured in the same manner as in Examples 1 to 3. The results are shown in Table 1.
【００３１】実施例４〜６
公共下水処理場Ｂにて採取した汚泥を用いたほかは、実
施例１〜３と同様にして悪臭成分の濃度を測定した。結
果を表１に示す。Examples 4 to 6 The concentrations of malodorous components were measured in the same manner as in Examples 1 to 3 except that the sludge collected at the public sewage treatment plant B was used. The results are shown in Table 1.
【００３２】比較例９〜１１
公共下水処理場Ｂにて採取した汚泥を用いたほかは、比
較例１、５または７と同様にして悪臭成分の濃度を測定
した。結果を表１に示す。Comparative Examples 9 to 11 The concentrations of the malodorous components were measured in the same manner as in Comparative Examples 1, 5 and 7 except that the sludge collected at the public sewage treatment plant B was used. The results are shown in Table 1.
【００３３】比較例１２
公共下水処理場Ｂの汚泥を用い、実施例１と同量となる
よう亜硝酸ソーダとＯＤＳを汚泥に添加し、混合し、直
ちに悪臭成分（硫化水素とメチルメルカプタン）濃度を
検知管で測定し、無添加に比べ５０％を超える悪臭成分
濃度が検出されたことを確認した。つぎに実施例１と同
様に脱水し、汚泥脱水ケーキの悪臭成分を測定した。Comparative Example 12 Using sludge from a public sewage treatment plant B, sodium nitrite and ODS were added to the sludge in the same amounts as in Example 1, mixed and immediately mixed with malodorous components (hydrogen sulfide and methyl mercaptan). Was measured with a detector tube, and it was confirmed that a malodorous component concentration exceeding 50% was detected as compared with the case of no addition. Then, the sludge was dehydrated in the same manner as in Example 1 to measure the malodorous components of the sludge dehydrated cake.
【００３４】[0034]
【表１】 [Table 1]
【００３５】前記結果から、亜硝酸ソーダ水溶液と腐敗
抑制剤（ＯＤＳ）とを配合してなる懸濁液を脱臭剤とし
て用いた場合（実施例１〜６）は、亜硝酸ソーダ水溶液
または腐敗抑制剤（ＯＤＳ）をそれぞれ単独で用いた場
合（比較例２〜４）と比較して、脱臭効果の即効性およ
び持続性がともに優れ、併用効果があることがわかる。
また、亜硝酸ソーダ水溶液と腐敗抑制剤としてＺＰＴま
たはＮａＰＴとを併用して、別個に添加した場合（比較
例５〜８、１０および１１））には、長期持続性に問題
がある。さらに、腐敗抑制剤として、ＺＰＴを用いた場
合（比較例５、６および１０）は、重金属を含むので、
得られる汚泥脱水ケーキの再利用において問題がある。From the above results, when the suspension prepared by mixing the sodium nitrite aqueous solution and the decay inhibitor (ODS) was used as the deodorant (Examples 1 to 6), the sodium nitrite aqueous solution or the decay inhibitor was used. As compared with the case where each of the agents (ODS) is used alone (Comparative Examples 2 to 4), it is understood that both immediate effect and sustainability of the deodorizing effect are excellent, and there is a combined effect.
Further, when a sodium nitrite aqueous solution and ZPT or NaPT as a spoilage inhibitor are used in combination and added separately (Comparative Examples 5 to 8, 10 and 11), there is a problem in long-term sustainability. Furthermore, when ZPT is used as the decay inhibitor (Comparative Examples 5, 6 and 10), since it contains heavy metals,
There is a problem in reusing the resulting sludge dewatering cake.
【００３６】脱臭剤を添加し、汚泥から発生する悪臭成
分濃度が添加前に比べ、５０％を超える状態で脱水すれ
ば長期持続性に劣ることがわかった。It was found that when a deodorant was added and the malodorous component concentration generated from the sludge was dehydrated in a state of exceeding 50%, the long-term sustainability was poor.
【００３７】[0037]
【発明の効果】本発明の脱臭剤は、一液型であるので、
汚泥脱水ケーキの脱臭における処理操作が簡便である。
本発明の一液型の汚泥脱水ケーキ用脱臭剤は、脱臭効果
の即効性および持続性が優れている。本発明の汚泥脱水
ケーキ用脱臭剤（汚泥脱臭方法）を適用して得られる脱
水ケーキは、重金属を含有しないので再利用するために
有利である。汚泥から発生する悪臭成分の濃度を基準と
して脱水する本発明の汚泥脱水ケーキの脱臭方法によれ
ば、脱臭効果の持続性を害することなく、効率よく汚泥
を処理することができる。Since the deodorant of the present invention is a one-pack type,
The processing operation for deodorizing the sludge dewatering cake is simple.
INDUSTRIAL APPLICABILITY The one-pack type deodorant for sludge dewatering cake of the present invention is excellent in immediate effect and durability of deodorizing effect. The dewatering cake obtained by applying the deodorant for sludge dewatering cake (sludge deodorizing method) of the present invention does not contain heavy metals and is therefore advantageous for reuse. According to the deodorizing method of a sludge dewatering cake of the present invention, which is dehydrated based on the concentration of the malodorous component generated from the sludge, the sludge can be efficiently treated without impairing the sustainability of the deodorizing effect.
Claims (7)
を含有しない腐敗抑制剤とを配合した懸濁液からなるこ
とを特徴とする一液型の汚泥脱水ケーキ用脱臭剤。1. A one-pack type deodorant for a sludge dewatering cake, comprising a suspension in which an aqueous nitrite solution and a spoilage inhibitor containing neither heavy metal nor chlorine are mixed.
が２：１〜８０：１（重量比）である請求項１記載の脱
臭剤。2. The deodorant according to claim 1, wherein the ratio of the nitrite to the putrefaction inhibitor is 2: 1 to 80: 1 (weight ratio).
％以上である請求項１または２記載の脱臭剤。3. The deodorant according to claim 1, wherein the nitrite concentration of the nitrite aqueous solution is 4% by weight or more.
リジン−１，１’−ジオキシドである請求項１、２また
は３記載の脱臭剤。4. The deodorant according to claim 1, 2 or 3, wherein the decay inhibitor is 2,2′-dithiobis-pyridine-1,1′-dioxide.
２、３または４記載の脱臭剤。5. The method according to claim 1, further comprising a thickening stabilizer.
The deodorant according to 2, 3, or 4.
臭剤を汚泥に添加したのち、脱水することを特徴とする
汚泥脱水ケーキの脱臭方法。6. A method for deodorizing a sludge dewatering cake, which comprises adding the deodorant according to claim 1, 2, 3, 4 or 5 to sludge and then dehydrating it.
臭剤を汚泥に添加したのち、汚泥から発生する硫化水素
およびメチルメルカプタンの各々の濃度が、脱臭剤添加
前の汚泥から発生する硫化水素およびメチルメルカプタ
ンの各々の濃度の５０％以下となったのち、脱水するこ
とを特徴とする汚泥脱水ケーキの脱臭方法。7. The concentration of hydrogen sulfide and methyl mercaptan generated from the sludge after the deodorant according to claim 1, 2, 3, 4 or 5 is added to the sludge is generated from the sludge before the addition of the deodorant. A method for deodorizing a sludge dewatering cake, which comprises dewatering after the respective concentrations of hydrogen sulfide and methyl mercaptan are reduced to 50% or less.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2001222887A JP3628285B2 (en) | 2001-07-24 | 2001-07-24 | Deodorant for sludge dewatering cake and deodorizing method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2001222887A JP3628285B2 (en) | 2001-07-24 | 2001-07-24 | Deodorant for sludge dewatering cake and deodorizing method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JP2003033797A true JP2003033797A (en) | 2003-02-04 |
| JP3628285B2 JP3628285B2 (en) | 2005-03-09 |
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ID=19056301
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2006075703A (en) * | 2004-09-08 | 2006-03-23 | Asahi Kasei Chemicals Corp | Deodorant and deodorizing method |
| JP2006075704A (en) * | 2004-09-08 | 2006-03-23 | Asahi Kasei Chemicals Corp | Deodorant and deodorization method |
-
2001
- 2001-07-24 JP JP2001222887A patent/JP3628285B2/en not_active Expired - Lifetime
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2006075703A (en) * | 2004-09-08 | 2006-03-23 | Asahi Kasei Chemicals Corp | Deodorant and deodorizing method |
| JP2006075704A (en) * | 2004-09-08 | 2006-03-23 | Asahi Kasei Chemicals Corp | Deodorant and deodorization method |
| JP4652753B2 (en) * | 2004-09-08 | 2011-03-16 | 旭化成ケミカルズ株式会社 | Deodorant and method |
Also Published As
| Publication number | Publication date |
|---|---|
| JP3628285B2 (en) | 2005-03-09 |
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