JPH0228391B2 - KOJOHAIEKITONODATSUHISHORIHO - Google Patents
KOJOHAIEKITONODATSUHISHORIHOInfo
- Publication number
- JPH0228391B2 JPH0228391B2 JP11516287A JP11516287A JPH0228391B2 JP H0228391 B2 JPH0228391 B2 JP H0228391B2 JP 11516287 A JP11516287 A JP 11516287A JP 11516287 A JP11516287 A JP 11516287A JP H0228391 B2 JPH0228391 B2 JP H0228391B2
- Authority
- JP
- Japan
- Prior art keywords
- arsenic
- iron
- waste liquid
- precipitate
- ferrous sulfate
- 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 - Lifetime
Links
- 229910052785 arsenic Inorganic materials 0.000 claims description 32
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 31
- RQNWIZPPADIBDY-UHFFFAOYSA-N arsenic atom Chemical compound [As] RQNWIZPPADIBDY-UHFFFAOYSA-N 0.000 claims description 31
- 239000007788 liquid Substances 0.000 claims description 21
- 239000002244 precipitate Substances 0.000 claims description 18
- 239000002699 waste material Substances 0.000 claims description 17
- 229910052742 iron Inorganic materials 0.000 claims description 16
- 238000000034 method Methods 0.000 claims description 12
- 241000894006 Bacteria Species 0.000 claims description 9
- BAUYGSIQEAFULO-UHFFFAOYSA-L iron(2+) sulfate (anhydrous) Chemical compound [Fe+2].[O-]S([O-])(=O)=O BAUYGSIQEAFULO-UHFFFAOYSA-L 0.000 claims description 9
- 239000011790 ferrous sulphate Substances 0.000 claims description 7
- 235000003891 ferrous sulphate Nutrition 0.000 claims description 7
- 229910000359 iron(II) sulfate Inorganic materials 0.000 claims description 7
- 238000005273 aeration Methods 0.000 claims description 6
- VTYYLEPIZMXCLO-UHFFFAOYSA-L Calcium carbonate Chemical compound [Ca+2].[O-]C([O-])=O VTYYLEPIZMXCLO-UHFFFAOYSA-L 0.000 claims description 4
- 230000001590 oxidative effect Effects 0.000 claims description 3
- 229910000019 calcium carbonate Inorganic materials 0.000 claims description 2
- 229910000358 iron sulfate Inorganic materials 0.000 claims description 2
- 239000012530 fluid Substances 0.000 claims 1
- 230000003472 neutralizing effect Effects 0.000 claims 1
- 229910052751 metal Inorganic materials 0.000 description 11
- 239000002184 metal Substances 0.000 description 11
- 150000002739 metals Chemical class 0.000 description 11
- 238000006386 neutralization reaction Methods 0.000 description 8
- 239000003610 charcoal Substances 0.000 description 7
- CWYNVVGOOAEACU-UHFFFAOYSA-N Fe2+ Chemical compound [Fe+2] CWYNVVGOOAEACU-UHFFFAOYSA-N 0.000 description 5
- 229910001448 ferrous ion Inorganic materials 0.000 description 5
- 239000002351 wastewater Substances 0.000 description 5
- 239000008267 milk Substances 0.000 description 4
- 210000004080 milk Anatomy 0.000 description 4
- 235000013336 milk Nutrition 0.000 description 4
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 4
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 3
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 description 3
- 229910052782 aluminium Inorganic materials 0.000 description 3
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 3
- 238000007796 conventional method Methods 0.000 description 3
- 229910052802 copper Inorganic materials 0.000 description 3
- 239000010949 copper Substances 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 230000003647 oxidation Effects 0.000 description 3
- 238000007254 oxidation reaction Methods 0.000 description 3
- 229910052725 zinc Inorganic materials 0.000 description 3
- 239000011701 zinc Substances 0.000 description 3
- VTLYFUHAOXGGBS-UHFFFAOYSA-N Fe3+ Chemical compound [Fe+3] VTLYFUHAOXGGBS-UHFFFAOYSA-N 0.000 description 2
- 238000003723 Smelting Methods 0.000 description 2
- 230000000052 comparative effect Effects 0.000 description 2
- 229910001447 ferric ion Inorganic materials 0.000 description 2
- 238000011084 recovery Methods 0.000 description 2
- 239000006228 supernatant Substances 0.000 description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- 238000007664 blowing Methods 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 238000000975 co-precipitation Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000007599 discharging Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- -1 iron ions Chemical class 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 238000010992 reflux Methods 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 239000013049 sediment Substances 0.000 description 1
- 239000010802 sludge Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
Landscapes
- Removal Of Specific Substances (AREA)
- Purification Treatments By Anaerobic Or Anaerobic And Aerobic Bacteria Or Animals (AREA)
- Treatment Of Water By Oxidation Or Reduction (AREA)
Description
〔産業上の利用分野〕
この発明は、少なくとも砒素と硫酸第１鉄を含
む工場等の廃液中から上記砒素を効率的に除去し
て無砒素鉄澱物を回収し、廃液中の有用金属を有
効に利用できるようにした脱砒処理法に関する。
〔従来の技術及びその問題点〕
鉱山や製練の排水または工場廃液等には、硫酸
第１鉄を主体としたものが多く、これらの廃水処
理に当たつて生ずる多量の鉄澱物中には、多くの
有用金属が含有されているところから、これらを
回収して有効利用を図ることが強く望まれてい
る。
しかしながら、一般に、この種鉄澱物中には可
成りの砒素が含まれている場合が多く、有用金属
の回収には該砒素を分離除去する必要がある。
而して、上記砒素を分離するに当たつて従来
は、砒素と硫酸第１鉄を含む工場等の廃液を脱砒
中和槽に導入し、予め該溶液のPHが６程度になる
ように相当量の炭酸カルシウム（以下「炭カル」
と略称する）を加えつゝ曝気して、その第１鉄イ
オンの一部を酸化させて第２鉄イオンにすること
により、これが上記炭カルと反応して生成する鉄
澱物中に砒素を吸着・共沈させるようにしたもの
である（特許第1281102号参照）。
ところで、この種硫酸第１鉄を含む廃液中に、
鉄以外にアルミニウム、銅、亜鉛等の有用金属が
含まれている場合、上記PH条件下での曝気中和手
段では、これらの各金属類も砒素と共沈してしま
うため、その回収が不可能となる他、いきおい沈
澱物量も多くなつて、その堆積場所の確保に困難
を来す等、種々の問題点が見られたものである。
又、PH３以下の低PH下で鉄酸化バクテリアを利
用して第１鉄イオンを酸化する方法も一部で開発
されているが、砒素の除去効率が相対的に低く、
特に多量の砒素を含有する廃液処理には不向きな
面が見受けられたものであつた。
〔問題点を解決するための手段〕
そこで本発明者は、工場廃液等に含まれる鉄以
外のアルミニウム、銅、亜鉛等の有用金属類がPH
４付近（以下「中PH」という）では砒素と共沈し
難い事実、並びに廃液中の砒素As3+が酸化され
てAs5+となつた場合、第２鉄イオンと吸着・共
沈し易い点などに着目し、鋭意、実験研究の結
果、上記硫酸第１鉄を含む廃液中に炭カルを添加
するに当たり、中和槽内の廃液のPHが常に４〜
4.5の中PHを維持するように設定し、該廃液を曝
気すると同時に別途鉄酸化バクテリアが吸着した
塩基性硫酸鉄を加えることによつて、上述した
種々の問題点を一挙に解消したものである。
〔作用〕
叙上の技術的手段に係る本発明は、含砒鉄澱物
中に他の有用金属が混在することを確実に抑制す
る一方、曝気と鉄酸化バクテリアによつて廃液中
の第１鉄イオンと砒素の酸化を効率的に行うとい
う作用を奏するものである。
〔実施例〕
以下、本発明方法を図面に示す実施例に従つて
更に具体的に述べると、脱砒中和槽１に砒素及び
硫酸第１鉄を含む廃液２を流送した後、当初は別
途培養された所定量の鉄酸化バクテリアを投入す
ると共に、圧気３による曝気と制御バルブ４′を
介してパイプ流送に適する濃度の炭カル乳４を供
給可能としたものである。
但し、上記炭カル乳の供給量はPHメーター５と
連動する上記制御バルブ４′によつて脱砒中和槽
１内の廃液２のPHが常時４程度に維持されるよう
に自動調整する。
このようにして酸化と中和が進行した処理液６
は、回収槽７に送られて含砒鉄澱物８を沈降分離
する一方、その上澄水９は次工程に流送されて、
該上澄水に含有される有用金属が分離回収される
のである。
而して、上記含砒鉄澱物８中には、鉄酸化バク
テリアが濃縮状態で吸着しているから、該澱物８
の一部を上記中和槽１に還流させ、残量はダム等
に放流廃棄するものである。
尚、上述の還流して利用される上記鉄澱物８
は、これに吸着する鉄酸化バクテリアによる中和
槽内での第１鉄イオンの過度の酸化を防止するた
め、調整バルブ１０を設けてその系内還流量を適
宜調整するものである。
次に本発明の実験例として20／minの鉱山排
水に対し、0.25m3／m2／minの圧気によつて曝気
すると共に、炭カル乳を供給してPH４の中PH下で
鉄酸化バクテリアを加えて第１鉄イオンを酸化し
た場合の脱砒処理結果を第１表に示す。
[Industrial Application Field] This invention efficiently removes arsenic from waste liquid from factories, etc., which contains at least arsenic and ferrous sulfate, recovers arsenic-free iron precipitate, and removes useful metals from the waste liquid. This invention relates to a method for removing arsenic that can be used effectively. [Conventional technology and its problems] Mine and smelting wastewater or factory wastewater are mainly composed of ferrous sulfate, and a large amount of iron precipitate is generated during the treatment of these wastewaters. Because it contains many useful metals, there is a strong desire to recover and effectively utilize these metals. However, generally, this type of iron precipitate often contains a considerable amount of arsenic, and it is necessary to separate and remove the arsenic in order to recover useful metals. In order to separate the above arsenic, conventionally, waste liquid from factories containing arsenic and ferrous sulfate is introduced into a dearsenic neutralization tank, and the pH of the solution is adjusted to about 6 in advance. A considerable amount of calcium carbonate (hereinafter referred to as "charcoal")
) is added and aerated to oxidize a portion of the ferrous ions to ferric ions, which react with the carbonaceous carbon to produce arsenic in the iron precipitate. It is designed to adsorb and co-precipitate (see Patent No. 1281102). By the way, in the waste liquid containing this type of ferrous sulfate,
If useful metals such as aluminum, copper, and zinc are included in addition to iron, the above-mentioned aeration neutralization method under the PH conditions will cause these metals to co-precipitate with arsenic, making it impossible to recover them. In addition to this, various problems have been observed, such as the increasing amount of precipitate, making it difficult to secure a place to deposit it. Additionally, some methods have been developed to oxidize ferrous ions using iron-oxidizing bacteria under a low pH of 3 or less, but the arsenic removal efficiency is relatively low;
In particular, it was found that the method was unsuitable for treating waste liquid containing a large amount of arsenic. [Means for Solving the Problems] Therefore, the present inventor discovered that useful metals other than iron, such as aluminum, copper, and zinc, contained in factory waste liquid, etc.
4 (hereinafter referred to as "medium PH"), it is difficult to co-precipitate with arsenic, and when arsenic As 3+ in the waste liquid is oxidized to As 5+ , it is easy to adsorb and co-precipitate with ferric ions. As a result of intensive experimental research, we focused on these points and found that when adding charcoal to the waste liquid containing ferrous sulfate, the pH of the waste liquid in the neutralization tank was always 4 to 4.
The above-mentioned problems were solved all at once by setting a medium pH of 4.5, aerating the waste liquid, and simultaneously adding basic iron sulfate to which iron-oxidizing bacteria had been adsorbed. . [Operation] The present invention, which is based on the technical means described above, reliably suppresses the presence of other useful metals in the arsenic-containing precipitate, while at the same time suppressing the primary metals in the waste liquid by aeration and iron-oxidizing bacteria. It has the effect of efficiently oxidizing iron ions and arsenic. [Example] Hereinafter, the method of the present invention will be described in more detail according to an example shown in the drawings. In addition to charging a predetermined amount of iron-oxidizing bacteria that has been separately cultured, it is possible to supply charcoal milk 4 of a concentration suitable for pipe transportation through aeration with pressurized air 3 and a control valve 4'. However, the supply amount of the charcoal milk is automatically adjusted by the control valve 4' interlocked with the PH meter 5 so that the pH of the waste liquid 2 in the arsenization neutralization tank 1 is always maintained at about 4. Processing liquid 6 that has been oxidized and neutralized in this way
is sent to a recovery tank 7 to sediment and separate the arsenic-containing precipitate 8, while the supernatant water 9 is sent to the next step,
The useful metals contained in the supernatant water are separated and recovered. Therefore, since iron-oxidizing bacteria are adsorbed in a concentrated state in the arsenic-containing iron precipitate 8, the arsenic-containing precipitate 8
A portion of the water is returned to the neutralization tank 1, and the remaining amount is disposed of by discharging it into a dam or the like. In addition, the above-mentioned iron precipitate 8 which is refluxed and used
In order to prevent excessive oxidation of ferrous ions in the neutralization tank due to iron-oxidizing bacteria adsorbed thereto, a regulating valve 10 is provided to appropriately adjust the amount of reflux within the system. Next, as an experimental example of the present invention, mine drainage at 20/min was aerated with pressurized air at 0.25 m 3 /m 2 /min, and charcoal milk was supplied to incubate iron oxidizing bacteria under a medium pH of 4. Table 1 shows the results of arsenization treatment when ferrous ions were oxidized by adding .
【表】
比較例 １
第２表は回分式試験により液中鉄濃度545mg／
、液中砒素濃度3.61mg／の鉱山排水６に予
め18ｇの炭カルを加え、毎分0.45m3／m2の圧気を
吹込んでPH6.0で曝気撹拌した従来の脱砒素法に
よる結果である。[Table] Comparative Example 1 Table 2 shows the iron concentration in liquid of 545mg/
This is the result of a conventional arsenic removal method in which 18 g of charcoal was added in advance to mine drainage 6 with a liquid arsenic concentration of 3.61 mg/min, and air was aerated and stirred at pH 6.0 by blowing in pressure air at a rate of 0.45 m 3 /m 2 per minute. .
【表】
比較例 ２
第３表は第１図に示す設備により、PH６程度で
化学的酸化による20／minの鉱山排水を0.4
m3／m2／minの圧気を送つて曝気酸化、脱砒中和
を行つた従来方法に基づく連続試験結果である。[Table] Comparative Example 2 Table 3 shows that using the equipment shown in Figure 1, mine drainage at a rate of 20/min by chemical oxidation at a pH of about 6 was 0.4
These are continuous test results based on a conventional method in which air under pressure of m 3 /m 2 /min was sent for aeration oxidation, arsenic removal and neutralization.
以上述べたように本発明方法は、鉱山や製練の
排水または工場廃液をPH４〜4.5の中PHに維持し
た上、曝気と鉄酸化バクテリアを併用して第１鉄
イオンの酸化を経済的速度で行うことによつて、
脱砒処理時に砒素だけが容易に鉄澱物中に吸着・
共沈して除去されるものであるから、その処理液
から鉄以外のアルミニウム、銅、亜鉛等の有用金
属の回収も可能となるものである。
又、本発明によれば上記砒素はAs3+からAs5+
に酸化されて、鉄澱物に容易に吸着・共沈するこ
とから、砒素の除去効率が高められ、これに伴つ
て該脱砒処理に要する鉄分の消費量も必要最小限
に止められ、従来方法に比較して廃棄される澱物
量が著しく少量となる等、その経済的効果は多大
である。
As described above, the method of the present invention maintains mine or smelting wastewater or factory wastewater at a medium pH of 4 to 4.5, and uses a combination of aeration and iron-oxidizing bacteria to oxidize ferrous ions at an economical rate. By doing this,
During the arsenic removal process, only arsenic is easily adsorbed into the iron precipitate.
Since it is removed by coprecipitation, it is also possible to recover useful metals other than iron, such as aluminum, copper, and zinc, from the treatment solution. Further, according to the present invention, the arsenic is As 3+ to As 5+
Because it is easily adsorbed and co-precipitated with iron precipitates, the removal efficiency of arsenic is increased, and the consumption of iron required for the arsenic removal process is also kept to the minimum necessary, compared to conventional methods. The economic effects are significant, such as the amount of sludge discarded is significantly smaller than that of the conventional method.
第１図は本発明方法の実施に使用した廃液処理
設備の一例を示す配置図である。
尚、図中１……脱砒中和槽、２……廃液、３…
…圧気、４……炭カル乳、５……PHメーター、６
……処理液、７……回収槽、８……含砒鉄澱物、
９……上澄水。
FIG. 1 is a layout diagram showing an example of waste liquid treatment equipment used in carrying out the method of the present invention. In addition, in the figure 1... arsenization neutralization tank, 2... waste liquid, 3...
...Pressure, 4...Charcoal milk, 5...PH meter, 6
...Treatment liquid, 7...Recovery tank, 8...Arsenic-containing precipitate,
9. Clear water.
Claims (1)
化バクテリアを吸着した塩基性硫酸鉄を加え、更
にこの混合液（廃液）のPHが4.0〜4.5になるよう
に炭酸カルシウムを添加して曝気し、上記硫酸第
１鉄の一部および砒素の酸化と同時に中和を行う
ことによつて生成する鉄澱物に砒素を吸着・共沈
させることを特徴とした含砒素工場廃液等の脱砒
処理法。1 Add basic iron sulfate that has adsorbed iron-oxidizing bacteria to waste liquid from factories that contains arsenic and ferrous sulfate, and then add calcium carbonate so that the pH of this mixed liquid (waste liquid) is 4.0 to 4.5. A method for removing arsenic-containing factory waste fluid, etc., which is characterized by adsorbing and co-precipitating arsenic into the iron precipitate produced by aeration and simultaneously oxidizing and neutralizing a part of the ferrous sulfate and arsenic. Arsenic treatment method.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP11516287A JPH0228391B2 (en) | 1987-05-12 | 1987-05-12 | KOJOHAIEKITONODATSUHISHORIHO |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP11516287A JPH0228391B2 (en) | 1987-05-12 | 1987-05-12 | KOJOHAIEKITONODATSUHISHORIHO |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS63278593A JPS63278593A (en) | 1988-11-16 |
| JPH0228391B2 true JPH0228391B2 (en) | 1990-06-22 |
Family
ID=14655869
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP11516287A Expired - Lifetime JPH0228391B2 (en) | 1987-05-12 | 1987-05-12 | KOJOHAIEKITONODATSUHISHORIHO |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0228391B2 (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2002320979A (en) * | 2001-04-27 | 2002-11-05 | Sharp Corp | Method and system for treating metal-containing drainage |
| JP2005000823A (en) * | 2003-06-12 | 2005-01-06 | Japan Science & Technology Agency | Method for treating geothermal water |
Families Citing this family (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| ES2215685T3 (en) * | 1999-06-22 | 2004-10-16 | Paques Bio Systems B.V. | ARSENIC IMMOBILIZATION PROCESS OF A DISPOSAL CONTAINER. |
| JP4520963B2 (en) * | 2006-06-29 | 2010-08-11 | Ｄｏｗａテクノエンジ株式会社 | Bacterial oxidation method of ferrous ions contained in low pH wastewater |
| JP5578730B2 (en) * | 2011-02-17 | 2014-08-27 | 国立大学法人九州大学 | Arsenic treatment method |
| JP5734225B2 (en) * | 2012-03-01 | 2015-06-17 | 国立大学法人九州大学 | Arsenic treatment method |
| JP6133561B2 (en) * | 2012-08-29 | 2017-05-24 | 国立大学法人九州大学 | Arsenic treatment method |
| CN106495215B (en) * | 2016-11-02 | 2017-08-25 | 林子柯 | A kind of method that magnesium arsenate is produced containing arsenic waste solution |
| CN106698821B (en) * | 2016-12-20 | 2019-06-28 | 中南大学 | A method of utilizing microbiological treatment waste water containing trivalent arsenic |
-
1987
- 1987-05-12 JP JP11516287A patent/JPH0228391B2/en not_active Expired - Lifetime
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2002320979A (en) * | 2001-04-27 | 2002-11-05 | Sharp Corp | Method and system for treating metal-containing drainage |
| JP2005000823A (en) * | 2003-06-12 | 2005-01-06 | Japan Science & Technology Agency | Method for treating geothermal water |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS63278593A (en) | 1988-11-16 |
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