JPH03165814A - Method for removing impurity from solution after gypsum separation - Google Patents
Method for removing impurity from solution after gypsum separationInfo
- Publication number
- JPH03165814A JPH03165814A JP1303193A JP30319389A JPH03165814A JP H03165814 A JPH03165814 A JP H03165814A JP 1303193 A JP1303193 A JP 1303193A JP 30319389 A JP30319389 A JP 30319389A JP H03165814 A JPH03165814 A JP H03165814A
- Authority
- JP
- Japan
- Prior art keywords
- exchange membrane
- solution
- impurities
- gypsum
- membrane
- 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
- 239000012535 impurity Substances 0.000 title claims abstract description 36
- 229910052602 gypsum Inorganic materials 0.000 title claims abstract description 24
- 239000010440 gypsum Substances 0.000 title claims abstract description 24
- 238000000926 separation method Methods 0.000 title claims abstract description 24
- 238000000034 method Methods 0.000 title claims description 17
- 239000012528 membrane Substances 0.000 claims abstract description 38
- 239000002002 slurry Substances 0.000 claims abstract description 22
- 238000005341 cation exchange Methods 0.000 claims abstract description 18
- 239000003011 anion exchange membrane Substances 0.000 claims abstract description 16
- FAPWRFPIFSIZLT-UHFFFAOYSA-M Sodium chloride Chemical compound [Na+].[Cl-] FAPWRFPIFSIZLT-UHFFFAOYSA-M 0.000 claims abstract description 8
- 239000011780 sodium chloride Substances 0.000 claims abstract description 4
- 238000010521 absorption reaction Methods 0.000 claims description 22
- 239000003014 ion exchange membrane Substances 0.000 claims description 11
- VTYYLEPIZMXCLO-UHFFFAOYSA-L Calcium carbonate Chemical compound [Ca+2].[O-]C([O-])=O VTYYLEPIZMXCLO-UHFFFAOYSA-L 0.000 claims description 10
- 229910000019 calcium carbonate Inorganic materials 0.000 claims description 5
- XTQHKBHJIVJGKJ-UHFFFAOYSA-N sulfur monoxide Chemical class S=O XTQHKBHJIVJGKJ-UHFFFAOYSA-N 0.000 claims description 5
- 229910052815 sulfur oxide Inorganic materials 0.000 claims description 5
- AXCZMVOFGPJBDE-UHFFFAOYSA-L calcium dihydroxide Chemical compound [OH-].[OH-].[Ca+2] AXCZMVOFGPJBDE-UHFFFAOYSA-L 0.000 claims description 4
- 239000000920 calcium hydroxide Substances 0.000 claims description 4
- 229910001861 calcium hydroxide Inorganic materials 0.000 claims description 4
- 239000000706 filtrate Substances 0.000 abstract description 19
- 239000012466 permeate Substances 0.000 abstract description 5
- -1 Cl<-> and F<-> Chemical class 0.000 abstract description 4
- 150000002500 ions Chemical class 0.000 abstract description 4
- 150000001450 anions Chemical class 0.000 abstract description 3
- 150000003839 salts Chemical class 0.000 abstract description 2
- 150000001768 cations Chemical class 0.000 abstract 1
- 239000007789 gas Substances 0.000 description 14
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 description 12
- 239000003546 flue gas Substances 0.000 description 12
- 238000006477 desulfuration reaction Methods 0.000 description 8
- 230000023556 desulfurization Effects 0.000 description 8
- 239000000243 solution Substances 0.000 description 8
- 230000002745 absorbent Effects 0.000 description 7
- 239000002250 absorbent Substances 0.000 description 7
- 239000007788 liquid Substances 0.000 description 7
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 6
- 238000010586 diagram Methods 0.000 description 6
- 239000002562 thickening agent Substances 0.000 description 6
- 239000000428 dust Substances 0.000 description 5
- 230000003647 oxidation Effects 0.000 description 5
- 238000007254 oxidation reaction Methods 0.000 description 5
- 239000011575 calcium Substances 0.000 description 4
- 235000010216 calcium carbonate Nutrition 0.000 description 4
- 230000000694 effects Effects 0.000 description 4
- 239000012530 fluid Substances 0.000 description 4
- 239000002351 wastewater Substances 0.000 description 4
- 235000011116 calcium hydroxide Nutrition 0.000 description 3
- GBAOBIBJACZTNA-UHFFFAOYSA-L calcium sulfite Chemical compound [Ca+2].[O-]S([O-])=O GBAOBIBJACZTNA-UHFFFAOYSA-L 0.000 description 3
- 235000010261 calcium sulphite Nutrition 0.000 description 3
- 238000005260 corrosion Methods 0.000 description 3
- 230000007797 corrosion Effects 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- 239000007921 spray Substances 0.000 description 3
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 3
- 235000008733 Citrus aurantifolia Nutrition 0.000 description 2
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 2
- 235000011941 Tilia x europaea Nutrition 0.000 description 2
- 238000009825 accumulation Methods 0.000 description 2
- OSGAYBCDTDRGGQ-UHFFFAOYSA-L calcium sulfate Chemical compound [Ca+2].[O-]S([O-])(=O)=O OSGAYBCDTDRGGQ-UHFFFAOYSA-L 0.000 description 2
- 150000001875 compounds Chemical class 0.000 description 2
- 238000002347 injection Methods 0.000 description 2
- 239000007924 injection Substances 0.000 description 2
- 239000004571 lime Substances 0.000 description 2
- 230000009257 reactivity Effects 0.000 description 2
- 239000006228 supernatant Substances 0.000 description 2
- RWSOTUBLDIXVET-UHFFFAOYSA-N Dihydrogen sulfide Chemical group S RWSOTUBLDIXVET-UHFFFAOYSA-N 0.000 description 1
- 238000005349 anion exchange Methods 0.000 description 1
- 125000000129 anionic group Chemical group 0.000 description 1
- 239000003245 coal Substances 0.000 description 1
- 238000002485 combustion reaction Methods 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 238000005342 ion exchange Methods 0.000 description 1
- 125000003010 ionic group Chemical group 0.000 description 1
- 210000005240 left ventricle Anatomy 0.000 description 1
- 239000003595 mist Substances 0.000 description 1
- 239000012452 mother liquor Substances 0.000 description 1
- 238000012856 packing Methods 0.000 description 1
- 238000005191 phase separation Methods 0.000 description 1
- 238000001556 precipitation Methods 0.000 description 1
- 239000000047 product Substances 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 238000005507 spraying Methods 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
- 238000004065 wastewater treatment Methods 0.000 description 1
Landscapes
- Treating Waste Gases (AREA)
- Separation Using Semi-Permeable Membranes (AREA)
- Water Treatment By Electricity Or Magnetism (AREA)
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は湿式排煙脱硫法における石膏分離濾液中の不純
物を除去する方法に関する。DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method for removing impurities in a gypsum separation filtrate in a wet flue gas desulfurization method.
現在、排煙脱硫の主流をなしているものにＣａＣＯ３や
Ｃａ （ＯＨ） ２を吸収剤として排煙脱硫を行い、亜
硫酸カルシウムや硫酸カルシウム（石膏）として回収す
るいわゆる湿式石灰法の排煙脱硫装置があり、例えば、
特開昭５７−６３１１７号等の他、多くの刊行物に詳述
されている通りである。Currently, the main stream of flue gas desulfurization is the so-called wet lime method flue gas desulfurization equipment, which desulfurizes flue gas using CaCO3 or Ca(OH)2 as an absorbent and recovers it as calcium sulfite or calcium sulfate (gypsum). For example,
This is described in detail in many publications including JP-A No. 57-63117.
ここで、第４図によって現在、工業的に広く採用されて
いる湿式石灰法による排煙脱硫装置の例を説明する。Here, an example of a flue gas desulfurization apparatus using the wet lime method, which is currently widely adopted industrially, will be explained with reference to FIG.
石炭焚きボイラの排煙を脱硝装置、エアーヒー夕、乾式
集塵装置で処理した後、乾式集塵装置を通過したダスト
、ｌ｛Ｃｌ 、ＩＩＰ， Ｓｏ３やＳＯ。を含んだ排煙
ｌは吸収塔本体２に導かれる。吸収塔本体２の下部には
Ｃａ化合物を懸濁したスラリを受けるタンク３が設けて
あり、攪拌機４によりスラリを攪拌して固形物の沈澱を
防止する。After treating the flue gas from a coal-fired boiler with a denitrification device, an air heater, and a dry dust collector, the dust that passes through the dry dust collector contains l{Cl, IIP, So3, and SO. The flue gas l containing the is led to the absorption tower main body 2. A tank 3 for receiving slurry in which Ca compounds are suspended is provided at the bottom of the absorption tower body 2, and the slurry is stirred by a stirrer 4 to prevent precipitation of solids.
Ｃａ化合物を懸濁したスラリは吸収塔循環ポンプ５によ
って塔頂に送られ、塔内に散布されて排煙と接触しなが
ら流下し再びタンク３に戻る。The slurry in which the Ca compound is suspended is sent to the top of the tower by the absorption tower circulation pump 5, spread inside the tower, flows down while coming into contact with flue gas, and returns to the tank 3 again.
スラリと接触してダスト、ＩＩＣｌ 、ＨＰＳＳＯ．や
Ｓ０２を除去された排煙はミストエリミネータ６を通っ
て浄化ガス７として排出される。一方、タンク３へはＳ
０２吸収量に見合ってＣａＣＯ３やＣａ （Ｏｔｌ）
２のスラリをライン８より供給すると共に、吸収剤がＳ
Ｏ。を吸収して生或した亜硫酸カルシウムを含むスラリ
をライン９から酸化塔１０へ導く。In contact with the slurry, dust, IICl, HPSSO. The exhaust gas from which S02 and S02 have been removed passes through a mist eliminator 6 and is discharged as purified gas 7. On the other hand, S to tank 3
02 CaCO3 and Ca (Otl) according to the amount of absorption
2 slurry is supplied from line 8, and the absorbent is
O. A slurry containing calcium sulfite produced by absorbing the oxidation tower 10 is led from line 9 to oxidation tower 10.
スラリ中にはダスト、ＨＣｌ 、ＩＩＦも捕集される。Dust, HCl, and IIF are also collected in the slurry.
酸化塔１０では底部に設けた気泡発生器１１から空気１
２を吹き込み、ライン１３から硫酸を供給して亜硫酸カ
ルシウムを酸化して石膏にすると共に、未反応のＣａＣ
Ｏ３やＣａ （ＯＨ） ２を石膏に転化する。酸化塔１
０から出た石膏スラリはライン１４を通ってシックナ１
５に導かれ、濃縮石膏スラリはラインｌ６、タンク１７
、ポンプ１８、遠心分離機１９へ送られ、石膏２０を得
ると共に濾過液はタンク２１へ導かれ、ポンプ２２及び
ライン２３を経由してシックナ１５へ導かれる。In the oxidation tower 10, air 1 is supplied from a bubble generator 11 provided at the bottom.
2 is blown in, and sulfuric acid is supplied from line 13 to oxidize calcium sulfite into gypsum, and remove unreacted CaC.
Converts O3 and Ca(OH)2 into gypsum. Oxidation tower 1
The gypsum slurry coming out from 0 passes through line 14 to thickener 1.
5, and the concentrated gypsum slurry goes to line 16 and tank 17.
, a pump 18 and a centrifugal separator 19 to obtain gypsum 20, and the filtrate is led to a tank 21 and then to a thickener 15 via a pump 22 and a line 23.
方、シックナ１５の上澄み液はライン２４からタンク２
５へ導かれ、ポンプ２６から排煙脱硫装置内の例えば吸
収剤の調製用に使用されると同時に一部は排水される。On the other hand, the supernatant liquid of thickener 15 is transferred from line 24 to tank 2.
5, and is used for preparing an absorbent in the flue gas desulfurization equipment through a pump 26, and at the same time, a portion is drained.
この溶液中には排ガス中から捕集されたＨＣｌやＨＦが
Ｃｌ−イオン、Ｆ−イオンとして存在しており、系外へ
排水する場合には２次公害防止のための排水処理が必要
である。HCl and HF collected from the exhaust gas exist in this solution as Cl- ions and F- ions, and when draining out of the system, wastewater treatment is required to prevent secondary pollution. .
なお、前記吸収塔２と酸化塔１０の作用を同一の塔で行
わせる場合もある。Note that the functions of the absorption tower 2 and the oxidation tower 10 may be performed in the same tower.
以上のように、従来は排ガス中のＳＯ２を吸収塔で吸収
・除去する工程において排ガス中のＨＣｌ 、ｌＩＩ’
も同時に吸収・除去されるため、吸収液中にＣｌ− 、
Ｐ−の不純物が混入していた。そして、吸収塔出口スラ
リ中の石膏を分離した後の濾液は、その一部を排水し大
半を吸収塔に戻すために、不純物（Ｃｌ一及びＦ一等）
が高濃度に蓄積されていた。As mentioned above, conventionally, in the process of absorbing and removing SO2 in exhaust gas with an absorption tower, HCl, lII'
are also absorbed and removed at the same time, so Cl-,
P- impurity was mixed in. After separating the gypsum in the slurry at the outlet of the absorption tower, the filtrate is partially drained and most of it is returned to the absorption tower, so that impurities (such as Cl and F) are removed.
had accumulated at high concentrations.
従って、循環液中の不純物濃度が高く、例えば、Ｃｌ−
は５， ０００ 〜２５， ＯＯＯｐｐｍ程度に濃縮さ
れており、その結果、装置の材質として耐食性の高い高
級材料が必要となり装置費が高くなっていた。また、不
純物濃度が高いために、硫黄酸化物の吸収剤であるＣａ
ＣＯ３の反応性が低下する欠点があった。Therefore, the concentration of impurities in the circulating fluid is high, such as Cl-
is concentrated to about 5,000 to 25,000 ppm, and as a result, a high-grade material with high corrosion resistance is required for the equipment, increasing the cost of the equipment. In addition, due to the high impurity concentration, Ca, which is an absorbent for sulfur oxides,
There was a drawback that the reactivity of CO3 was reduced.
本発明は上記技術水準に鑑み、吸収塔出口のスラリから
石膏を除去した後の溶液中から、不純物（Ｃｌ−及びＦ
一等）を選択的に分離・除去し、■吸収液中の不純物濃
度を低減する、■除去したＣｌ−をＨＣｌとして回収し
、排水処理するか、再利用する、■除去したＯＨ一をＮ
ａ叶として回収し、再利用することができる方法を提供
しようとするものである。In view of the above-mentioned state of the art, the present invention has been developed to remove impurities (Cl- and F) from the solution after removing gypsum from the slurry at the outlet of the absorption tower.
1) selectively separates and removes the
The aim is to provide a method that allows the leaves to be collected and reused.
本発明は、
〔１）硫黄酸化物及び不純物を含む排ガスを吸収塔内で
炭酸カルシウムまたは水酸化カルシウムスラリと接触さ
せて、排ガス中の硫黄酸化物を吸収・除去する工程にお
いて、吸収塔出口のスラリ中の石膏を分離した後の溶液
から、アニオン交換膜とカチオン交換膜を使用して該溶
液中のＣｌ− ， Ｆ一及びＮａ十などを除去した後、
該溶液を前記吸収塔に循環供給することを特徴とする石
膏分離後の溶液の不純物除去方法。The present invention provides the following features: [1) In the process of bringing exhaust gas containing sulfur oxides and impurities into contact with calcium carbonate or calcium hydroxide slurry in an absorption tower to absorb and remove sulfur oxides from the exhaust gas, After separating the gypsum in the slurry, an anion exchange membrane and a cation exchange membrane are used to remove Cl, F, Na, etc. from the solution.
A method for removing impurities from a solution after gypsum separation, comprising circulating and supplying the solution to the absorption tower.
（２） アニオン交換膜、カチオン交換膜の外に、Ｈ
２０をＯＨ一とＨ＋に分離する性能を有する両性イオン
交換膜を使用して不純物であるじＩＦ＝及びＮａ＋をＨ
Ｃｌ ， ＩＩＦ及びＮａＣｌ溶液として回収する上記
（１）記載の石膏分離後の溶液の不純物除去方法。(2) In addition to the anion exchange membrane and cation exchange membrane, H
Using an amphoteric ion exchange membrane that has the ability to separate 20 into OH- and H+, the impurities IF= and Na+ are separated into H+.
The method for removing impurities from a solution after gypsum separation according to (1) above, wherein the solution is recovered as a Cl, IIF and NaCl solution.
である。It is.
本発明はイオン交換膜（アニオン交換膜と力チオン交換
膜）を使用することにより、さらには、０■一と旧イオ
ンを選択的に分離・除去する両性イオン交換膜と前記イ
オン交換膜とを組合せることにより効率的に石膏分離濾
液中の不純物を選択的に分離・除去する方法である。The present invention uses an ion exchange membrane (an anion exchange membrane and a thion exchange membrane), and furthermore, uses an amphoteric ion exchange membrane and the ion exchange membrane that selectively separates and removes 0 and 1 and old ions. By combining these methods, it is possible to efficiently selectively separate and remove impurities in the gypsum separation filtrate.
本発明の作用を以下第２図及び第３図により説明する。The operation of the present invention will be explained below with reference to FIGS. 2 and 3.
第２図はアニオン交換膜とカチオン交換膜のみを使用し
た場合の膜分離装置の構或を示す概要図である。この膜
分離装置は両側に陽極ａと陰極ｂとが設けられ両極間の
室をアニオン交換膜Ｃ，カチオン交換膜ｄにより３室ｘ
，ｙ，ｚに区画されている。FIG. 2 is a schematic diagram showing the structure of a membrane separation device using only an anion exchange membrane and a cation exchange membrane. This membrane separator has an anode a and a cathode b on both sides, and the chambers between the two electrodes are divided into three chambers by an anion exchange membrane C and a cation exchange membrane d.
, y, and z.
不純物を蓄積している石膏分離後の濾液ｅが上記膜分離
装置の真中の室Ｙに供給されると、不純物のうちアニオ
ン交換膜Ｃ側をＣｌ−，Ｐ−などの陰イオンが透過して
左室Ｘに移行し、カチオン交換膜ｄ側をＮａ＋などの陽
イオンが透過して右室Ｚに移行し、濾液の不純物は希釈
されて不純物希釈濾液ｆとして膜分離装置より出て行き
、吸収塔に循環使用される。When the filtrate e after gypsum separation that has accumulated impurities is supplied to the chamber Y in the middle of the membrane separation device, anions such as Cl- and P- among the impurities permeate through the anion exchange membrane C side. It moves to the left ventricle It is recycled to the tower.
一方、アニオン交換膜Ｃ，カチオン交換膜ｄを透過した
各イオン（Ｃｌ− ， Ｆ−， Ｎａ＋など）は再度混
合して不純物塩（例えばＮａＣｌなど〉として濃縮され
、一部は膜分離装置の左右の室Ｘ，Ｚに循環され、残部
は不純物濃縮濾液ｇとして膜分離装置から取出され、排
水処理されて系外に放出される。On the other hand, the ions (Cl-, F-, Na+, etc.) that have passed through the anion exchange membrane C and the cation exchange membrane d are mixed again and concentrated as impurity salts (e.g. NaCl), and some of them are transferred to the left and right sides of the membrane separation device. The remainder is taken out from the membrane separator as an impurity-concentrated filtrate g, treated as waste water, and discharged outside the system.
第３図は上記のアニオン交換膜とカチオン交換膜の外に
、叶一とＨ＋を選択的に分離する両性イオン交換膜を使
用した膜分離装置の構或を示す概要図である。FIG. 3 is a schematic diagram showing the structure of a membrane separation device that uses, in addition to the above-mentioned anion exchange membrane and cation exchange membrane, an amphoteric ion exchange membrane for selectively separating Kanoichi and H+.
第３図の膜分離装置は第２図の左右の室Ｘ，Ｚを両性イ
オン交換膜ｈによって、それぞれＸ．Ｘ′室及びｚ，ｚ
’室に２分割され、全体として５室を構或するもので、
不純物含有濾液Ｃは第２図の膜分離装置と同じように真
中の室Ｙに供給されるが、左右の室ｘ，ｘ’及びｚ，ｚ
’には水が供給されるようになっている。The membrane separator shown in FIG. 3 separates the left and right chambers X and Z in FIG. 2 by amphoteric ion exchange membranes h, respectively. X' room and z, z
It is divided into two rooms, and has five rooms in total.
The impurity-containing filtrate C is supplied to the middle chamber Y in the same way as the membrane separator shown in Figure 2, but the left and right chambers x, x' and z, z
' has been supplied with water.
陽極ａ側の両性イオン交換膜ｈでは水はＯＨとＨ＋に解
離され、解離したＨ＋は室Ｘに移行し、前記第２図に関
して説明したようにアニオン交換膜Ｃを透過してくるＣ
ｌ− ， Ｆ一などと結合しＨＣｌ ， ＨＦが生或す
る。一方、陰極ｂ側の両性イオン交換膜ｈでも水はＯＨ
−とＨ＋に解離され、解離した０■−は室Ｚに移行し、
前記第２図に関して説明したようにカチオン交換膜ｄを
透過してくるＮａ−などと結合しＮａＯＨが生或される
。In the amphoteric ion exchange membrane h on the anode a side, water is dissociated into OH and H+, the dissociated H+ moves to chamber
It combines with l-, F-, etc. to produce HCl and HF. On the other hand, even in the amphoteric ion exchange membrane h on the cathode b side, water is OH
- and H+, and the dissociated 0■- moves to chamber Z,
As explained with reference to FIG. 2, NaOH is produced by combining with Na-, etc., which permeate the cation exchange membrane d.
生或したＩＩｃＩ ， ［’及びＮａＯＨは各々系外に
抜出され、各々目的に応じて使用されるか、排水として
処理され、真中の室Ｙから出てくる不純物希釈濾液ｆは
吸収塔に循環使用される。The raw IIcI, [' and NaOH are each extracted from the system and used depending on the purpose or treated as waste water, and the impurity diluted filtrate f coming out of the middle chamber Y is recycled to the absorption tower. used.
両性イオン交換膜とは、陽イオン交換基と陰イオン基と
を併せもつものであって、更にイオン交換基の分布状態
からみると、一つのイオン交換膜内に均一に陽イオン交
換基及び陰イオン基が分布しているもの、一つの領域に
陽イオン交換基が存在し、他の領域に陰イオン基が存在
し、それぞれの領域がモザイク様の構造をしたもの、更
にモザイク様の構造をしたもの＼中に陽イオン交換基を
有する相と陰イオン基を有すｑ
る相がミクロ的に存在する、いわゆるミクロ相分離構造
をしたものがある。An amphoteric ion exchange membrane is one that has both cation exchange groups and anion exchange groups, and looking at the distribution of the ion exchange groups, the cation exchange groups and anion exchange membranes are uniformly distributed within one ion exchange membrane. Those with ionic groups distributed, those with cation exchange groups in one region and anionic groups in another region, and those with a mosaic-like structure in each region, and those with a mosaic-like structure. Some products have a so-called micro phase separation structure in which a phase with cation exchange groups and a phase with anion groups exist microscopically.
以上のように、特定のイオンを選択分離する性能を有す
る膜分離装置を使用することにより、循環液中の不純物
（Ｃｌ− ， Ｆ一及びＮａ＋など）を分離・除去する
ことにより、不純物の高濃度蓄積を防止することができ
、その結果、装置材質として耐食性が高い高級材料を使
用する必要がなくなる。As described above, by using a membrane separator that has the ability to selectively separate specific ions, impurities (Cl-, F-, Na+, etc.) in the circulating fluid can be separated and removed, thereby reducing the concentration of impurities. Concentration accumulation can be prevented, and as a result, there is no need to use high-grade materials with high corrosion resistance as the material for the device.
以上の構或の不純物処理方法を使用して行った実験の実
施例により、本発明の効果を説明する。The effects of the present invention will be explained by examples of experiments conducted using the impurity treatment method having the above structure.
〔実施例１〕 本発明の実施例を第１図に従って説明する。[Example 1] An embodiment of the present invention will be described with reference to FIG.
吸収塔２の上部に排ガス人口４１が設けられ、下部側に
は排ガス出口４２が設けられている。An exhaust gas population 41 is provided in the upper part of the absorption tower 2, and an exhaust gas outlet 42 is provided in the lower part.
排ガス出口４２より下方の吸収塔２内には容量１００β
の吸収液貯蔵タシク３があり、攪拌機４及び空気注入管
８が配置されている。吸収塔２の上部には炭酸カルシウ
ムを含むスラリをス１０
プレするスプレノズル４３が配置され、スプレノズル４
３は途中に循環ポンプ５を具えた配管９により吸収液貯
蔵タンク３と運通している。The absorption tower 2 below the exhaust gas outlet 42 has a capacity of 100β.
There is an absorption liquid storage tank 3 in which an agitator 4 and an air injection pipe 8 are arranged. A spray nozzle 43 for spraying a slurry containing calcium carbonate is arranged in the upper part of the absorption tower 2.
3 communicates with the absorption liquid storage tank 3 through a pipe 9 equipped with a circulation pump 5 in the middle.
ガス流量２ ０ ０ Ｎｍ３／ｈ ，ガス温度１１０℃
、ＳＯ２濃度２，ＯＯＯｐｐｍの石炭燃焼炉排ガスを排
ガス人口４１より導入し、同時にスプレノズル４３より
４ ｍ３／ｈでスラリを噴出させて排ガスと気液接触さ
せ、さらに格子状充填物４４より落下するスラリを吸収
液貯蔵タンク３において攪拌機４で攪拌しながら空気注
入管８から供給される空気と気液接触させた。Gas flow rate 200 Nm3/h, gas temperature 110℃
, a coal combustion furnace exhaust gas with an SO2 concentration of 2,00ppm is introduced from the exhaust gas population 41, and at the same time slurry is spouted from the spray nozzle 43 at a rate of 4 m3/h to bring it into gas-liquid contact with the exhaust gas, and the slurry falling from the lattice-shaped packing 44 is was brought into gas-liquid contact with air supplied from an air injection pipe 8 in the absorption liquid storage tank 3 while stirring with a stirrer 4.
同時に、吸収液貯蔵タンク３と連結しているポンプ５の
吐出スラリの一部を配管１２を通ってシックナ１５に導
き、濃縮石膏スラリを配管１６、タンク１７、ポンプ１
８、遠心分離機１９へ送り、石膏２０を得ると共に濾過
液はタンク２１へ導き、ポンプ２２及びライン２３を経
由してシックナ１５へ供給した。At the same time, a part of the slurry discharged from the pump 5 connected to the absorbent storage tank 3 is led to the thickener 15 through the pipe 12, and the concentrated gypsum slurry is transferred to the pipe 16, the tank 17, and the pump 1.
8. The filtrate was sent to a centrifuge 19 to obtain gypsum 20, and the filtrate was led to a tank 21 and supplied to the thickener 15 via a pump 22 and line 23.
一方、シックナ１５の上澄み液はライン２４から第２図
に示した膜分離装置４６へ導いた。On the other hand, the supernatant liquid of the thickener 15 was led from the line 24 to the membrane separation device 46 shown in FIG.
１１
この膜分離装置４６から排出される不純物濃縮濾液はポ
ンプ２６により配管２７を経て系外に抜出して排水処理
して放出し、不純物希釈濾液はポンプ３１により配管３
２を経て吸収塔２上部のスプレノズル４３に通ずる配管
９に循環サせた。11 The impurity-concentrated filtrate discharged from the membrane separator 46 is extracted from the system via the pipe 27 by the pump 26, treated as waste water, and discharged, and the impurity-diluted filtrate is transferred to the pipe 3 by the pump 31.
2 and then circulated through a pipe 9 leading to a spray nozzle 43 at the top of the absorption tower 2.
第１表に膜分離装置を使用しない場合と、第２表と膜分
離装置を使用した場合との各部（第１図の○印の付した
符号部分）る分析結果の１例を示す。Table 1 shows an example of the analysis results for the case where no membrane separator is used, and Table 2 and the case where a membrane separator is used (the parts marked with ○ in FIG. 1).
１
２
第１表と第２表を比較して明確なように、膜分離装置を
使用することにより循環液中の不純物量を減少すること
ができた。1 2 As is clear from a comparison of Tables 1 and 2, the amount of impurities in the circulating fluid could be reduced by using the membrane separation device.
〔実施例２〕
実施例１で示した第１図の装置を使用し、膜分離装置４
６としては第３図のものを使用した。[Example 2] Using the device shown in FIG. 1 shown in Example 1, the membrane separation device 4
6 was used as shown in Fig. 3.
不純物希釈濾液は実施例１と同様に配管９に循環し、生
或した｝ＩＣｌ ， ＩＦは排水処理を施して系外に放
出し、ＮａＯ旧ま排煙脱硫装置内で使用する吸収剤の調
製用に使用した。The impurity diluted filtrate is circulated through the pipe 9 in the same manner as in Example 1, and the raw ICl and IF are treated with wastewater and discharged outside the system, and the NaO filtrate is used to prepare an absorbent to be used in the flue gas desulfurization equipment. used for.
第３表に第３図の膜分離装置を使用した場合の各部の分
析結果の１例を示す。Table 3 shows an example of the analysis results of each part when the membrane separator shown in FIG. 3 is used.
１
５
第１表と第３表を比較して明確なように、この膜分離装
置を使用することにより循環液中の不純物量を減少する
ことができた。1 5 As is clear from a comparison of Tables 1 and 3, the amount of impurities in the circulating fluid could be reduced by using this membrane separation device.
本発明により湿式排煙脱硫法における石膏分離濾液中の
不純物（Ｃｌ− ， Ｆ一及びＮａ” ）が大幅に除去
され、該濾液を吸収剤であるＣａＣＯｓスラリの母液と
する際に不純物の蓄積のために生じていたＣａＣロ，の
反応性の低下が防止されると共に、Ｃ１−が低下するた
め装置の腐食の問題が激減する効果を発揮させることが
できる。According to the present invention, impurities (Cl-, F1, and Na'') in the gypsum separation filtrate in the wet flue gas desulfurization method are largely removed, and when the filtrate is used as a mother liquor for the CaCOs slurry that is an absorbent, the accumulation of impurities can be avoided. This prevents a decrease in the reactivity of CaC, which would otherwise have occurred due to this, and also reduces C1-, thereby making it possible to exhibit the effect of drastically reducing the problem of corrosion of the equipment.
第１図は本発明の実施態様の説明図、第２図は本発明の
ア二オン交換膜、カチオン交換膜を使用する膜分離装置
の不純物除去機構の説明図、第３図は本発明のアニオン
交換膜、カチオン交換膜及び複合膜を使用する膜分＃ｌ
装置の不純物除去機構の説明図、第４図は従来の湿式排
煙脱硫法の説明図である。
１７FIG. 1 is an explanatory diagram of an embodiment of the present invention, FIG. 2 is an explanatory diagram of an impurity removal mechanism of a membrane separation device using an anion exchange membrane and a cation exchange membrane of the present invention, and FIG. Membrane fraction #l using anion exchange membrane, cation exchange membrane and composite membrane
An explanatory diagram of the impurity removal mechanism of the apparatus, and FIG. 4 is an explanatory diagram of the conventional wet flue gas desulfurization method. 17
Claims (2)
炭酸カルシウムまたは水酸化カルシウムスラリと接触さ
せて、排ガス中の硫黄酸化物を吸収・除去する工程にお
いて、吸収塔出口のスラリ中の石膏を分離した後の溶液
から、アニオン交換膜とカチオン交換膜を使用して該溶
液中のＣｌ＾−、Ｆ＾−及びＮａ＾＋などを除去した後
、該溶液を前記吸収塔に循環供給することを特徴とする
石膏分離後の溶液の不純物除去方法。(1) In the process of absorbing and removing sulfur oxides from the exhaust gas by bringing the exhaust gas containing sulfur oxides and impurities into contact with calcium carbonate or calcium hydroxide slurry in the absorption tower, gypsum is present in the slurry at the outlet of the absorption tower. After separating Cl^-, F^-, Na^+, etc. from the solution using an anion exchange membrane and a cation exchange membrane, the solution is circulated and supplied to the absorption tower. A method for removing impurities from a solution after gypsum separation, characterized by:
ＯをＯＨ＾−とＨ＾＋に分離する性能を有する両性イオ
ン交換膜を使用して不純物であるＣｌ＾−、Ｆ＾−及び
Ｎａ＾＋をＨＣｌ、ＨＦ及びＮａＣｌ溶液として回収す
ることを特徴とする請求項（１）記載の石膏分離後の溶
液の不純物除去方法。(2) In addition to the anion exchange membrane and cation exchange membrane, H_2
The feature is that impurities Cl^-, F^- and Na^+ are recovered as HCl, HF and NaCl solutions using an amphoteric ion exchange membrane that has the ability to separate O into OH^- and H^+. A method for removing impurities from a solution after gypsum separation according to claim (1).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1303193A JP2691036B2 (en) | 1989-11-24 | 1989-11-24 | Method for removing impurities from solution after gypsum separation |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1303193A JP2691036B2 (en) | 1989-11-24 | 1989-11-24 | Method for removing impurities from solution after gypsum separation |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH03165814A true JPH03165814A (en) | 1991-07-17 |
| JP2691036B2 JP2691036B2 (en) | 1997-12-17 |
Family
ID=17918000
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP1303193A Expired - Fee Related JP2691036B2 (en) | 1989-11-24 | 1989-11-24 | Method for removing impurities from solution after gypsum separation |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2691036B2 (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112354332A (en) * | 2020-11-03 | 2021-02-12 | 江南环保集团股份有限公司 | Method for applying membrane separation device to ammonia desulphurization |
| CN112607707A (en) * | 2020-12-16 | 2021-04-06 | 浙江天采云集科技股份有限公司 | Separation and purification method of FTrPSA refined from industrial-grade high-concentration HF into electronic grade |
| CN113860552A (en) * | 2021-10-11 | 2021-12-31 | 紫金矿业集团股份有限公司 | Method for removing fluorine and chlorine in mine smelting wastewater |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS53123555A (en) * | 1977-04-04 | 1978-10-28 | Tokuyama Soda Kk | Method of regenerating drainage |
| JPS62244427A (en) * | 1986-04-17 | 1987-10-24 | Kureha Chem Ind Co Ltd | Treatment for flue gas desulfurization absorption liquid |
-
1989
- 1989-11-24 JP JP1303193A patent/JP2691036B2/en not_active Expired - Fee Related
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS53123555A (en) * | 1977-04-04 | 1978-10-28 | Tokuyama Soda Kk | Method of regenerating drainage |
| JPS62244427A (en) * | 1986-04-17 | 1987-10-24 | Kureha Chem Ind Co Ltd | Treatment for flue gas desulfurization absorption liquid |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112354332A (en) * | 2020-11-03 | 2021-02-12 | 江南环保集团股份有限公司 | Method for applying membrane separation device to ammonia desulphurization |
| CN112607707A (en) * | 2020-12-16 | 2021-04-06 | 浙江天采云集科技股份有限公司 | Separation and purification method of FTrPSA refined from industrial-grade high-concentration HF into electronic grade |
| CN112607707B (en) * | 2020-12-16 | 2022-05-20 | 浙江天采云集科技股份有限公司 | Separation and purification method for FTrPSA (fluorine-doped silica gel) refined from industrial high-concentration HF (hydrogen fluoride) into electronic grade |
| CN113860552A (en) * | 2021-10-11 | 2021-12-31 | 紫金矿业集团股份有限公司 | Method for removing fluorine and chlorine in mine smelting wastewater |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2691036B2 (en) | 1997-12-17 |
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