JP2015182052A - Method of treating waste acid generated in copper smelting - Google Patents
Method of treating waste acid generated in copper smelting Download PDFInfo
- Publication number
- JP2015182052A JP2015182052A JP2014062926A JP2014062926A JP2015182052A JP 2015182052 A JP2015182052 A JP 2015182052A JP 2014062926 A JP2014062926 A JP 2014062926A JP 2014062926 A JP2014062926 A JP 2014062926A JP 2015182052 A JP2015182052 A JP 2015182052A
- Authority
- JP
- Japan
- Prior art keywords
- primary
- slurry
- waste acid
- gypsum
- liquid
- 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
- 238000000034 method Methods 0.000 title claims abstract description 82
- 239000002699 waste material Substances 0.000 title claims abstract description 58
- 239000002253 acid Substances 0.000 title claims abstract description 36
- 238000003723 Smelting Methods 0.000 title claims abstract description 17
- 229910052802 copper Inorganic materials 0.000 title claims abstract description 13
- 239000010949 copper Substances 0.000 title claims abstract description 13
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 title claims abstract description 12
- 239000002002 slurry Substances 0.000 claims abstract description 87
- 239000007788 liquid Substances 0.000 claims abstract description 79
- 239000010440 gypsum Substances 0.000 claims abstract description 51
- 229910052602 gypsum Inorganic materials 0.000 claims abstract description 51
- 238000000926 separation method Methods 0.000 claims abstract description 34
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 claims abstract description 30
- 239000003795 chemical substances by application Substances 0.000 claims abstract description 21
- UCKMPCXJQFINFW-UHFFFAOYSA-N Sulphide Chemical compound [S-2] UCKMPCXJQFINFW-UHFFFAOYSA-N 0.000 claims abstract description 18
- 229910001385 heavy metal Inorganic materials 0.000 claims abstract description 17
- 238000004519 manufacturing process Methods 0.000 claims abstract description 14
- 238000002156 mixing Methods 0.000 claims abstract description 5
- 238000005486 sulfidation Methods 0.000 claims description 56
- 230000008569 process Effects 0.000 claims description 41
- 229920002472 Starch Polymers 0.000 claims description 35
- 239000008107 starch Substances 0.000 claims description 35
- 235000019698 starch Nutrition 0.000 claims description 35
- HYHCSLBZRBJJCH-UHFFFAOYSA-M sodium hydrosulfide Chemical compound [Na+].[SH-] HYHCSLBZRBJJCH-UHFFFAOYSA-M 0.000 claims description 22
- 239000002562 thickening agent Substances 0.000 claims description 22
- VTYYLEPIZMXCLO-UHFFFAOYSA-L Calcium carbonate Chemical compound [Ca+2].[O-]C([O-])=O VTYYLEPIZMXCLO-UHFFFAOYSA-L 0.000 claims description 8
- RWSOTUBLDIXVET-UHFFFAOYSA-N Dihydrogen sulfide Chemical compound S RWSOTUBLDIXVET-UHFFFAOYSA-N 0.000 claims description 7
- 229910000037 hydrogen sulfide Inorganic materials 0.000 claims description 6
- 238000003672 processing method Methods 0.000 claims description 6
- 230000003472 neutralizing effect Effects 0.000 claims description 5
- 229910000019 calcium carbonate Inorganic materials 0.000 claims description 4
- AXCZMVOFGPJBDE-UHFFFAOYSA-L calcium dihydroxide Chemical compound [OH-].[OH-].[Ca+2] AXCZMVOFGPJBDE-UHFFFAOYSA-L 0.000 claims description 2
- 239000000920 calcium hydroxide Substances 0.000 claims description 2
- 229910001861 calcium hydroxide Inorganic materials 0.000 claims description 2
- BRPQOXSCLDDYGP-UHFFFAOYSA-N calcium oxide Chemical compound [O-2].[Ca+2] BRPQOXSCLDDYGP-UHFFFAOYSA-N 0.000 claims description 2
- 239000000292 calcium oxide Substances 0.000 claims description 2
- ODINCKMPIJJUCX-UHFFFAOYSA-N calcium oxide Inorganic materials [Ca]=O ODINCKMPIJJUCX-UHFFFAOYSA-N 0.000 claims description 2
- 150000004763 sulfides Chemical class 0.000 claims 1
- 230000018044 dehydration Effects 0.000 abstract description 44
- 238000006297 dehydration reaction Methods 0.000 abstract description 44
- 239000004744 fabric Substances 0.000 abstract description 22
- 238000012544 monitoring process Methods 0.000 abstract description 11
- 238000005987 sulfurization reaction Methods 0.000 abstract description 10
- 238000012423 maintenance Methods 0.000 abstract description 7
- 238000007689 inspection Methods 0.000 abstract description 6
- 239000002244 precipitate Substances 0.000 abstract description 2
- 239000007787 solid Substances 0.000 abstract description 2
- 239000011369 resultant mixture Substances 0.000 abstract 3
- 238000001556 precipitation Methods 0.000 abstract 2
- 238000009434 installation Methods 0.000 abstract 1
- 208000005156 Dehydration Diseases 0.000 description 42
- 238000010306 acid treatment Methods 0.000 description 23
- 239000006228 supernatant Substances 0.000 description 9
- 238000001914 filtration Methods 0.000 description 8
- 238000003860 storage Methods 0.000 description 8
- 239000000126 substance Substances 0.000 description 8
- 230000000052 comparative effect Effects 0.000 description 6
- 239000007789 gas Substances 0.000 description 6
- 238000006243 chemical reaction Methods 0.000 description 5
- 238000004065 wastewater treatment Methods 0.000 description 4
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 3
- 230000007423 decrease Effects 0.000 description 3
- 238000000746 purification Methods 0.000 description 3
- CDBYLPFSWZWCQE-UHFFFAOYSA-L Sodium Carbonate Chemical compound [Na+].[Na+].[O-]C([O-])=O CDBYLPFSWZWCQE-UHFFFAOYSA-L 0.000 description 2
- LSNNMFCWUKXFEE-UHFFFAOYSA-N Sulfurous acid Chemical compound OS(O)=O LSNNMFCWUKXFEE-UHFFFAOYSA-N 0.000 description 2
- 229910052785 arsenic Inorganic materials 0.000 description 2
- RQNWIZPPADIBDY-UHFFFAOYSA-N arsenic atom Chemical compound [As] RQNWIZPPADIBDY-UHFFFAOYSA-N 0.000 description 2
- 238000007599 discharging Methods 0.000 description 2
- 239000012535 impurity Substances 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 230000009467 reduction Effects 0.000 description 2
- 238000004062 sedimentation Methods 0.000 description 2
- 238000005406 washing Methods 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- OYPRJOBELJOOCE-UHFFFAOYSA-N Calcium Chemical compound [Ca] OYPRJOBELJOOCE-UHFFFAOYSA-N 0.000 description 1
- 235000019738 Limestone Nutrition 0.000 description 1
- 238000010521 absorption reaction Methods 0.000 description 1
- 150000007513 acids Chemical class 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 230000008901 benefit Effects 0.000 description 1
- 238000007664 blowing Methods 0.000 description 1
- 229910052791 calcium Inorganic materials 0.000 description 1
- 239000011575 calcium Substances 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 239000003638 chemical reducing agent Substances 0.000 description 1
- GTKRFUAGOKINCA-UHFFFAOYSA-M chlorosilver;silver Chemical compound [Ag].[Ag]Cl GTKRFUAGOKINCA-UHFFFAOYSA-M 0.000 description 1
- 238000004140 cleaning Methods 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 150000001879 copper Chemical class 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 230000003111 delayed effect Effects 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 238000004880 explosion Methods 0.000 description 1
- 239000000706 filtrate Substances 0.000 description 1
- 239000010419 fine particle Substances 0.000 description 1
- 239000003517 fume Substances 0.000 description 1
- 239000006028 limestone Substances 0.000 description 1
- 239000010687 lubricating oil Substances 0.000 description 1
- 239000000155 melt Substances 0.000 description 1
- 230000033116 oxidation-reduction process Effects 0.000 description 1
- 230000000737 periodic effect Effects 0.000 description 1
- 238000003825 pressing Methods 0.000 description 1
- 239000000047 product Substances 0.000 description 1
- 238000011084 recovery Methods 0.000 description 1
- 230000008439 repair process Effects 0.000 description 1
- 239000011734 sodium Substances 0.000 description 1
- 229910000029 sodium carbonate Inorganic materials 0.000 description 1
- 229910052979 sodium sulfide Inorganic materials 0.000 description 1
- GRVFOGOEDUUMBP-UHFFFAOYSA-N sodium sulfide (anhydrous) Chemical compound [Na+].[Na+].[S-2] GRVFOGOEDUUMBP-UHFFFAOYSA-N 0.000 description 1
- 231100000331 toxic Toxicity 0.000 description 1
- 230000002588 toxic effect Effects 0.000 description 1
Images
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
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P10/00—Technologies related to metal processing
- Y02P10/20—Recycling
Landscapes
- Removal Of Specific Substances (AREA)
- Manufacture And Refinement Of Metals (AREA)
Abstract
Description
本発明は、銅製錬において発生する廃酸から重金属を除去する廃酸の処理方法に関し、更に詳しくは脱水設備並びにその監視や保守点検の作業の削減を図ることができる廃酸の処理方法に関する。 The present invention relates to a waste acid treatment method for removing heavy metals from waste acid generated in copper smelting, and more particularly to a dehydration facility and a waste acid treatment method capable of reducing the monitoring and maintenance work.
従来から、銅製錬において発生する亜硫酸ガス（ＳＯ２）は、硫酸工場に送られ、ガス精製工程、乾燥工程、転化工程及び吸収工程を経て硫酸が製造されている。この銅製錬で発生する亜硫酸ガスのうち１〜３％程度は、ガス精製工程における冷却段階で冷却されて硫酸となる。しかし、ガス精製工程以前の製錬排ガス中には重金属を含む煙灰やヒュームが存在するため、こうして得られた硫酸（以降、廃酸と称する）には不純物が多く含まれ、製品硫酸とはならない。 Conventionally, sulfurous acid gas (SO 2 ) generated in copper smelting is sent to a sulfuric acid factory, and sulfuric acid is produced through a gas purification process, a drying process, a conversion process, and an absorption process. About 1 to 3% of the sulfurous acid gas generated in this copper smelting is cooled in the cooling stage in the gas purification process to become sulfuric acid. However, since smelting ash and fumes containing heavy metals exist in the smelting exhaust gas before the gas purification process, the sulfuric acid thus obtained (hereinafter referred to as waste acid) contains a lot of impurities and does not become product sulfuric acid. .
かかる廃酸の処理方法としては、特許文献１に記載されているように、硫酸分及び重金属を分離除去したうえで、排水処理工程へ送る方法が知られている。また、特許文献２に記載されているように、廃酸から重金属を分離除去したうえで、石膏を製造する方法が知られている。これら廃酸の処理方法の一具体例について、図１を参照して以下に説明する。 As a method for treating such waste acid, as described in Patent Document 1, a method of separating and removing sulfuric acid and heavy metals and sending them to a wastewater treatment step is known. Further, as described in Patent Document 2, a method for producing gypsum after separating and removing heavy metals from waste acid is known. One specific example of the treatment method of these waste acids will be described below with reference to FIG.
まず、廃酸を１次硫化工程において、１次硫化反応ステップ、１次分離ステップ及び１次脱水ステップの順に処理する。即ち、１次硫化反応ステップでは、廃酸に水硫化ナトリウム（ＮａＨＳ）又は硫化水素（Ｈ２Ｓ）を混合し、酸化還元電位（ＯＲＰ）約１２０ｍＶ（銀−塩化銀電極基準）として硫化澱物を含むスラリーを得る。このスラリーを１次分離ステップにおいて濃縮等により分離し、硫化澱物に富む１次スラリーと１次清澄液とを得る。この１次スラリーは１次脱水ステップで水分を低減させ、硫化澱物として製錬工程に送られる。 First, waste acid is treated in the order of a primary sulfurization reaction step, a primary separation step, and a primary dehydration step in a primary sulfurization step. That is, in the primary sulfidation reaction step, sodium hydrosulfide (NaHS) or hydrogen sulfide (H 2 S) is mixed with the waste acid, and a sulfurized starch having an oxidation-reduction potential (ORP) of about 120 mV (silver-silver chloride electrode standard). A slurry containing is obtained. This slurry is separated by concentration or the like in the primary separation step to obtain a primary slurry rich in sulfide starch and a primary clarified liquid. This primary slurry reduces moisture in the primary dehydration step and is sent to the smelting process as sulfide starch.
一方、１次分離ステップで得られた１次清澄液は、石膏前濾過ステップで濾過し、濾液として石膏始液を得る。得られた石膏始液は、次の石膏製造工程において、石灰石（炭酸カルシウム）を粉砕したものと反応させ、硫酸分を石膏として分離回収すると共に、硫酸分を取り除いた石膏終液を得る。 On the other hand, the primary clarified liquid obtained in the primary separation step is filtered in the pre-gypsum filtration step to obtain a gypsum starting liquid as the filtrate. The obtained gypsum starting liquid is reacted with pulverized limestone (calcium carbonate) in the next gypsum manufacturing process to separate and recover the sulfuric acid content as gypsum and obtain a gypsum final liquid from which the sulfuric acid content has been removed.
この石膏製造工程で得られた石膏終液は、２次硫化工程において２次硫化反応ステップ、２次分離ステップ及び２次脱水ステップの順に処理される。即ち、２次硫化反応ステップでは、石膏終液に水硫化ナトリウム又は硫化水素を混合し、ＯＲＰを約１０ｍＶとして硫化澱物を含むスラリーを得る。このスラリーを２次分離ステップで濃縮等により分離して、硫化澱物に富む２次スラリーと２次清澄液を得る。得られた２次スラリーは、２次脱水ステップで水分を低減させ、硫化澱物として回収して製錬工程へ送る。また、２次清澄液は排水処理工程に送られて処理される。 The gypsum final solution obtained in this gypsum manufacturing process is processed in the order of the secondary sulfidation reaction step, the secondary separation step, and the secondary dehydration step in the secondary sulfidation step. That is, in the secondary sulfidation reaction step, sodium hydrosulfide or hydrogen sulfide is mixed in the gypsum final solution to obtain a slurry containing sulfide starch with an ORP of about 10 mV. This slurry is separated by concentration or the like in the secondary separation step to obtain a secondary slurry rich in sulfide starch and a secondary clarified liquid. The obtained secondary slurry reduces moisture in the secondary dehydration step, collects it as a sulfide starch, and sends it to the smelting process. Further, the secondary clarified liquid is sent to the wastewater treatment process for processing.
上記した廃酸の処理方法は、廃酸の浄化だけでなく有価な石膏を回収できる点、石膏製造工程より前に１次硫化工程を経ることで廃酸から重金属を硫化澱物として除去でき、石膏の品質が向上する点、２次硫化工程より前に石膏製造工程があることで石膏終液の酸濃度を低減でき、２次硫化工程において硫化水素の発生を抑えながら反応を進められる点において優れている。 The above-mentioned waste acid treatment method can recover not only waste acid but also valuable gypsum, and can remove heavy metals as sulfurized starch from waste acid by passing through the primary sulfidation step before the gypsum production step. The point that the quality of gypsum is improved, and that there is a gypsum manufacturing process before the secondary sulfidation process, so that the acid concentration of the gypsum final solution can be reduced and the reaction can proceed while suppressing the generation of hydrogen sulfide in the secondary sulfidation process. Are better.
上記した従来の廃酸の処理方法において、１次及び２次硫化工程で得られる硫化澱物中に残存している水分は、硫化澱物が供給された製錬工程の炉内で水蒸気爆発を起こしたり炉内の熔体を凝固させたりして、重大なトラブルを発生させる危険がある。そのため、上記した廃酸の処理方法では、１次及び２次脱水ステップで回収した硫化澱物は、製錬工程に供給して炉に装入するまでの間に水分を十分に低減しておく必要がある。 In the conventional waste acid treatment method described above, the water remaining in the sulfurized starch obtained in the primary and secondary sulfidizing processes is subjected to a steam explosion in the furnace of the smelting process to which the sulfurized starch is supplied. There is a danger of causing serious troubles by causing them to solidify the melt in the furnace. Therefore, in the above-described waste acid treatment method, the sulfide starch recovered in the primary and secondary dehydration steps is sufficiently reduced in moisture before being supplied to the smelting process and charged into the furnace. There is a need.
そのため、上記廃酸の処理方法における１次脱水ステップ及び２次脱水ステップでは、硫化澱物を含むスラリー中の水分率を十分に低減できるような脱水方法が採用されている。具体的な脱水方法としてはフィルタープレスを用いることが多いが、その他の脱水方法として、脱水後の硫化澱物の水分率はフィルタープレスよりもやや高くなるが、真空式濾過機、ベルトプレス、遠心分離機の使用も可能である。 Therefore, in the primary dehydration step and the secondary dehydration step in the waste acid treatment method, a dehydration method that can sufficiently reduce the moisture content in the slurry containing sulfide starch is employed. As a specific dehydration method, a filter press is often used, but as another dehydration method, the moisture content of the dehydrated starch is slightly higher than that of the filter press, but a vacuum filter, belt press, centrifuge A separator can also be used.
しかし、上記脱水方法に共通の欠点として、単位時間あたりの処理能力が低いことが挙げられる。そこで従来は、低い脱水の処理能力を補うために、脱水設備を複数設置して並列処理を行うか、あるいは、脱水に先立って硫化澱物の濃縮を行い、硫化澱物から水分を分離しておくことが一般に行われている。例えば脱水すべき液量が多い場合には、濃縮方法としてシックナーを用いることが多い。 However, a common drawback of the dehydration method is that the processing capacity per unit time is low. Therefore, in the past, in order to compensate for the low dewatering capacity, multiple dehydration facilities were installed to perform parallel processing, or prior to dehydration, sulfide starch was concentrated to separate water from sulfide starch. It is generally done. For example, when the amount of liquid to be dehydrated is large, a thickener is often used as a concentration method.
上記脱水方法の中でフィルタープレスは回分式であり、閉板、濾過、圧搾、ブロー、開板、ケーキ排出及び濾布洗浄といった各操作が１つの設備で順次行われる。しかし、これらの操作の中でスラリーを処理できるのは濾過操作のみであり、従って濾過操作を行わない間は、フィルタープレスの前工程にある設備はスラリーの排出を停止する必要がある。 In the dehydration method, the filter press is a batch type, and each operation such as closing plate, filtration, pressing, blowing, opening plate, cake discharging and filter cloth washing is sequentially performed in one facility. However, only the filtration operation can process the slurry in these operations, and therefore, the equipment in the pre-process of the filter press needs to stop discharging the slurry while the filtration operation is not performed.
そこで、前工程にある設備の停止を避けるために、フィルタープレスの前段に貯液槽を設置し、フィルタープレスが濾過操作を行わない間は貯液槽にスラリーを貯めるという方法が行われているが、その場合でも貯液槽が満ちた場合には前工程にある設備を停止する必要がある。そのため、常に貯液槽の液位を監視して、次の濾過操作が開始するまでの間、スラリーを受け入れる余地が残っているか予測する必要があった。 Therefore, in order to avoid stopping the equipment in the previous process, a liquid storage tank is installed in the front stage of the filter press, and the slurry is stored in the liquid storage tank while the filter press does not perform the filtering operation. However, even in this case, when the liquid storage tank is full, it is necessary to stop the equipment in the previous process. Therefore, it is necessary to always monitor the liquid level in the liquid storage tank and predict whether there is room for receiving the slurry until the next filtration operation starts.
また、フィルタープレスの処理能力は、濾布の目詰まりによって時間と共に低下する。そのため、フィルタープレスは定期的な濾布洗浄によって濾布の目詰まりを取り除く機能を備えている。しかし、定期的な濾布洗浄によって目詰まりを完全に解消することはできず、処理能力の低下を遅らせることしかできない。この処理能力低下に対しては、ポンプを用いてフィルタープレスに高圧力で給液したり、それでも処理能力が十分でない場合は濾布を交換したりする。しかし、濾布の交換には時間と人手を要するため、貯液槽の空き容量に余裕がある間に多くの作業員で交換作業を行う必要がある。 Also, the throughput of the filter press decreases with time due to clogging of the filter cloth. Therefore, the filter press has a function of removing clogging of the filter cloth by periodically cleaning the filter cloth. However, clogging cannot be completely eliminated by periodic filter cloth washing, and only a reduction in processing capacity can be delayed. To reduce the processing capacity, a pump is used to supply liquid to the filter press at a high pressure, or when the processing capacity is still insufficient, the filter cloth is replaced. However, since replacement of the filter cloth requires time and manpower, it is necessary to perform replacement work by a large number of workers while there is a sufficient free space in the liquid storage tank.
更に、濾布の交換を要する状態として、濾布の目詰まり以外にも、濾布の破れが挙げられる。濾布が破れる原因としては、給液による化学的腐食、高圧力の給液による摩擦、給液中の固く尖った澱物や異物による力の集中、フィルタープレスを開閉する際の機械的衝撃などが挙げられる。濾布が破れると、給液圧力が低下して有効に濾過されず、破れ目からスラリーが飛散して失われるうえ、飛散したスラリーが周辺設備に入って故障や汚染の原因となることから、直ちに濾布の交換が必要となる。 Furthermore, as a state that requires replacement of the filter cloth, besides the filter cloth being clogged, the filter cloth is broken. Causes of filter cloth breaking include chemical corrosion due to liquid supply, friction due to high-pressure liquid supply, concentration of force due to hard and sharp starch and foreign matters in the liquid supply, mechanical impact when opening and closing the filter press, etc. Is mentioned. If the filter cloth is torn, the supply pressure will drop and it will not be filtered effectively. It is necessary to change the filter cloth.
このような濾布の破れに対しても、濾布交換による設備の停止時間を最小化するために、常に運転状態を監視し、給液されるスラリー中に異物が混入していないか、濾布に毛羽立ちや傷がないか、濾布表面に液のにじみはないか等により、濾布が破れる時期を予測する必要があった。また、フィルタープレスは可動部が多いため、監視項目として油圧は適切に維持されているか、歯車に潤滑油膜は形成されているか、濾板は割れていないか等も点検し、時間のかかる部品交換や補修の必要性を判断する必要がある。 Even when such a filter cloth breaks, in order to minimize the downtime of the equipment due to the filter cloth replacement, the operation state is constantly monitored to check whether foreign matter is mixed in the supplied slurry. It was necessary to predict when the filter cloth would break depending on whether the cloth had fuzz or scratches, or the surface of the filter cloth had smudged liquid. Since the filter press has many moving parts, it is necessary to check whether the hydraulic pressure is properly maintained as a monitoring item, whether a lubricating oil film is formed on the gear, whether the filter plate is cracked, etc. It is necessary to judge the need for repair.
本発明は、上記した従来の廃酸の処理方法における問題点に鑑みてなされたものであり、１次及び２次硫化工程で得られる硫化澱物に富むスラリーの各脱水ステップにおいて、脱水設備の監視や濾布交換等の保守点検に要する作業の削減を図り、効率的で経済性に優れた廃酸の処理方法を提供することを目的とする。 The present invention has been made in view of the problems in the conventional waste acid treatment method described above, and in each dehydration step of the slurry rich in sulfide starch obtained in the primary and secondary sulfidation steps, The purpose of the present invention is to reduce the work required for maintenance and inspection such as monitoring and filter cloth replacement, and to provide an efficient and economical waste acid treatment method.
本発明者らは、上記課題を解決するために検討を重ねた結果、例えば図１に示す従来の廃酸の処理方法において、１次スラリーと２次スラリーを単一の脱水ステップで処理することによって１次脱水ステップ及び２次脱水ステップの２つの脱水ステップを１つに集約することができれば、脱水設備の監視や保守点検に要する作業の低減になるとの着想を得た。この着想に基づき、２次硫化工程の２次分離ステップから産出する２次スラリーを１次硫化工程に繰り返して、１次分離ステップで更に液量を減少させれば、２次脱水ステップを廃止できることを見出し、本発明を完成するに至ったものである。 As a result of repeated studies to solve the above-described problems, the present inventors have processed the primary slurry and the secondary slurry in a single dehydration step, for example, in the conventional waste acid treatment method shown in FIG. The idea is that if the two dehydration steps, the primary dehydration step and the secondary dehydration step, can be integrated into one, the work required for dehydration equipment monitoring and maintenance inspection can be reduced. Based on this idea, the secondary dehydration step can be abolished if the secondary slurry produced from the secondary separation step of the secondary sulfidation step is repeated in the primary sulfidation step and the liquid volume is further reduced in the primary separation step. And the present invention has been completed.
即ち、本発明が提供する第１の廃酸の処理方法は、銅製錬で発生する廃酸に硫化剤を混合して重金属を硫化し、得られた硫化澱物を含む１次スラリーと１次清澄液とに分離する１次硫化工程と、１次清澄液に中和剤を混合して硫酸を石膏とし、固液分離して石膏終液を得る石膏製造工程と、石膏終液に硫化剤を混合して重金属を硫化し、得られた硫化澱物を含む２次スラリーと２次清澄液とに分離する２次硫化工程とを備え、２次硫化工程において２次清澄液を分離した２次スラリーを１次硫化工程に繰り返し、廃酸と混合することを特徴とする。 That is, in the first waste acid treatment method provided by the present invention, a primary slurry and a primary slurry containing a sulfided starch obtained by mixing a sulfurizing agent with waste acid generated in copper smelting to sulfidize heavy metals. A primary sulfidizing step for separating into a clarified liquid, a neutralizing agent mixed with the primary clarified liquid to make sulfuric acid into gypsum, a solid-liquid separation to obtain a gypsum final liquid, and a gypsum final liquid with a sulfurizing agent And a secondary slurry containing a secondary slurry containing the resulting sulfided starch and a secondary clarified liquid. The secondary clarified liquid was separated in the secondary sulfidizing process. The secondary slurry is repeated in the primary sulfiding step and mixed with waste acid.
また、本発明が提供する第２の廃酸の処理方法は、銅製錬で発生する廃酸に硫化剤を混合して重金属を硫化し、得られた硫化澱物を含む１次スラリーと１次清澄液とに分離する１次硫化工程と、１次清澄液に中和剤を混合して硫酸を石膏とし、固液分離して石膏終液を得る石膏製造工程と、石膏終液に硫化剤を混合して重金属を硫化し、得られた硫化澱物を含む２次スラリーと２次清澄液とに分離する２次硫化工程とを備え、２次硫化工程において２次清澄液を分離した２次スラリーを１次硫化工程に繰り返し、１次清澄液を分離した１次スラリーと混合することを特徴とする。 Further, the second waste acid treatment method provided by the present invention is to mix a sulfurizing agent with waste acid generated in copper smelting to sulfidize heavy metals, and to obtain a primary slurry and a primary slurry containing the obtained sulfided starch. A primary sulfidizing step for separating into a clarified liquid, a neutralizing agent mixed with the primary clarified liquid to make sulfuric acid into gypsum, a solid-liquid separation to obtain a gypsum final liquid, and a gypsum final liquid with a sulfurizing agent And a secondary slurry containing a secondary slurry containing the resulting sulfided starch and a secondary clarified liquid. The secondary clarified liquid was separated in the secondary sulfidizing process. The secondary slurry is repeated in the primary sulfiding step, and the primary clarified liquid is mixed with the separated primary slurry.
上記本発明による本発明が提供する第１及び第２の廃酸の処理方法において、前記１次硫化工程における１次スラリーと１次清澄液の分離、及び前記２次硫化工程における２次スラリーと２次清澄液の分離は、それぞれシックナーでの濃縮による分離であることが好ましい。その場合、上記２次硫化工程の濃縮分離で得られる２次スラリーの量は、１次硫化工程の濃縮分離で得られる１次スラリーの量に対して、１０〜５０体積％であることが好ましい。 In the first and second waste acid treatment methods provided by the present invention according to the present invention, separation of the primary slurry and primary clarified liquid in the primary sulfidation step, and secondary slurry in the secondary sulfidation step, The separation of the secondary clarified liquid is preferably separation by concentration with a thickener. In that case, the amount of the secondary slurry obtained by the concentration separation in the secondary sulfidation step is preferably 10 to 50% by volume with respect to the amount of the primary slurry obtained by the concentration separation in the primary sulfidation step. .
本発明によれば、銅製錬において発生する廃酸を処理する際に、１次及び２次硫化工程で得られる硫化澱物に富むスラリーの脱水ステップを一つに集約することができるため、脱水設備そのものも削減でき１つだけ設ければよい。従って、脱水設備の監視や濾布交換等の保守点検に要する作業の削減を図ることができ、効率的で経済性に優れた廃酸の処理が可能である。 According to the present invention, when the waste acid generated in copper smelting is treated, the dehydration step of the slurry rich in sulfide starch obtained in the primary and secondary sulfidation processes can be integrated into one, so that dehydration can be performed. The equipment itself can be reduced and only one is required. Therefore, it is possible to reduce the work required for maintenance inspection such as monitoring of dehydration equipment and filter cloth replacement, and it is possible to treat waste acid efficiently and economically.
本発明による第１の廃酸の処理方法は、図２に示すように、図１に示す従来の廃酸処理方法と比較して、２次硫化工程において２次清澄液を分離した２次スラリーを１次硫化工程に繰り返して廃酸と混合する点、及び、２次脱水ステップを廃止した点が異なる。この第１の廃酸の処理方法において、２次硫化工程から繰り返される２次スラリー中に含まれていた硫化澱物は、最終的に１次硫化工程における１次脱水ステップで分離される。 As shown in FIG. 2, the first waste acid treatment method according to the present invention is a secondary slurry obtained by separating the secondary clarified liquid in the secondary sulfidation step as compared with the conventional waste acid treatment method shown in FIG. Is different in that it is repeated in the primary sulfurization step and mixed with waste acid, and the secondary dehydration step is eliminated. In the first waste acid treatment method, the sulfide starch contained in the secondary slurry repeated from the secondary sulfidation step is finally separated in the primary dehydration step in the primary sulfidation step.
また、２次脱水ステップを廃止することによって、２次脱水ステップの脱水設備及びそれに付随する貯液槽などが不要になり、それらの監視や保守点検に要する作業を削減することができる。不要となった２次脱水ステップの脱水設備は、１次脱水ステップの予備機として使うことができる。予備機があれば、濾布交換などの作業によって脱水設備が長時間停止する場合でも、予備機を使用して安定した脱水処理を行うことが可能になる。 Further, by eliminating the secondary dehydration step, the dehydration equipment of the secondary dehydration step and the accompanying liquid storage tank become unnecessary, and the work required for monitoring and maintenance inspection can be reduced. The dehydration equipment for the secondary dehydration step that has become unnecessary can be used as a spare machine for the primary dehydration step. If there is a spare machine, even if the dehydration equipment is stopped for a long time due to work such as filter cloth replacement, it becomes possible to perform a stable dehydration process using the spare machine.
更に、２次硫化工程での２次スラリーを１次硫化工程に繰り返すことにより、２次硫化工程で未反応のまま残っている硫化剤を、従来のごとく排水処理工程に送って無駄にすることなく、１次硫化工程で再び利用することができる。そのため、従来の廃酸の処理方法に比べて１次硫化工程での硫化剤を節約でき、プロセス全体で硫化剤の使用量を減らすことができる。 Furthermore, by repeating the secondary slurry in the secondary sulfidation process to the primary sulfidation process, the sulfiding agent remaining unreacted in the secondary sulfidation process is sent to the wastewater treatment process as before and wasted. And can be reused in the primary sulfurization process. Therefore, it is possible to save the sulfiding agent in the primary sulfiding step as compared with the conventional waste acid treatment method, and it is possible to reduce the use amount of the sulfiding agent in the entire process.
本発明による第２の廃酸の処理方法は、図３に示すように、２次硫化工程において２次清澄液を分離した２次スラリーを１次硫化工程に繰り返し、１次清澄液を分離した１次スラリーと混合して、脱水ステップに直接送る方法である。この方法では、２次スラリーを１次硫化工程で濃縮等により再度分離することなく脱水するため、１次硫化工程での脱水ステップの処理能力が要求される反面、１次硫化工程での分離ステップの処理能力に余裕を持たせることができる。 As shown in FIG. 3, the second waste acid treatment method according to the present invention repeats the secondary slurry obtained by separating the secondary clarified liquid in the secondary sulfidation process in the primary sulfidation process, and separates the primary clarified liquid. It is a method in which it is mixed with the primary slurry and sent directly to the dehydration step. In this method, since the secondary slurry is dehydrated in the primary sulfidation step without being separated again by concentration or the like, the processing capacity of the dehydration step in the primary sulfidation step is required, but the separation step in the primary sulfidation step is required. The processing capacity can be given a margin.
また、この第２の廃酸の処理の方法による脱水ステップは、１次分離ステップと２次分離ステップの両方からスラリーを受け入れることから、両方のスラリーを予め混合したうえで脱水ステップに供給することも可能である。これによって、配管長さが節約できると共に、均一なスラリーを安定的に処理できる利点がある。 In addition, since the dehydration step by the second waste acid treatment method accepts the slurry from both the primary separation step and the secondary separation step, both slurries are mixed in advance and then supplied to the dehydration step. Is also possible. As a result, the piping length can be saved, and there is an advantage that a uniform slurry can be stably processed.
上記した本発明の１次硫化工程と２次硫化工程で用いる硫化剤としては、水硫化ナトリウム（硫化水素ナトリウム）、硫化水素、硫化ナトリウムといった一般的な硫化剤が使用可能である。これらの中で水硫化ナトリウムと硫化水素は、コストの点で優れており、石膏製造に適した硫酸濃度の石膏始液が得られる点で特に有利である。 As the sulfiding agent used in the above-described primary sulfiding step and secondary sulfiding step of the present invention, general sulfiding agents such as sodium hydrosulfide (sodium hydrogen sulfide), hydrogen sulfide, and sodium sulfide can be used. Among these, sodium hydrosulfide and hydrogen sulfide are excellent in terms of cost, and are particularly advantageous in that a gypsum starting solution having a sulfuric acid concentration suitable for gypsum production can be obtained.
また、本発明の石膏製造工程で用いる中和剤としては、炭酸カルシウム、水酸化カルシウム、酸化カルシウムなどの中和剤が使用可能である。これらの中和剤はコストの点で優れており、石膏へのカルシウム源となる点で特に有利である。なお、上記中和剤は、炭酸ナトリウムや水酸化ナトリウムを不純物として含んでいても、問題なく使用することができる。 Moreover, neutralizers, such as calcium carbonate, calcium hydroxide, and calcium oxide, can be used as the neutralizer used in the gypsum production process of the present invention. These neutralizing agents are excellent in terms of cost, and are particularly advantageous in that they become a calcium source for gypsum. The neutralizing agent can be used without any problem even if it contains sodium carbonate or sodium hydroxide as impurities.
上記した本発明による第１及び第２の廃酸の処理方法においては、図２及び図３に示すように、１次硫化工程における１次スラリーと１次清澄液の分離、及び２次硫化工程における２次スラリーと２次清澄液の分離は、それぞれシックナーでの濃縮による分離であることが好ましい。 In the above-described first and second waste acid treatment methods according to the present invention, as shown in FIGS. 2 and 3, the separation of the primary slurry and the primary clarified liquid in the primary sulfidation step and the secondary sulfidation step are performed. The secondary slurry and the secondary clarified liquid are preferably separated by concentration in a thickener.
特に上記第１の廃酸の処理方法では、シックナーでの濃縮を行うことによって、２次分離ステップから産出する濃縮された２次スラリーは、２次硫化反応ステップの産出液よりも液量が少なくなり、しかも、２次硫化反応ステップの産出液と同等の澱物を含んでいる。そのため、この濃縮された２次スラリーは、１次分離ステップで更に濃縮されることにより、液量を減少させることができる。その結果、脱水ステップで処理すべき液量は１次スラリーの量と２次スラリーの量の合計よりも少なくてすむため、上記した脱水設備の削減にも寄与する。 In particular, in the first waste acid treatment method, the concentrated secondary slurry produced from the secondary separation step has a smaller liquid volume than the produced solution of the secondary sulfidation reaction step by concentrating with a thickener. In addition, it contains starch equivalent to that produced in the secondary sulfurization reaction step. Therefore, the concentrated secondary slurry can be further concentrated in the primary separation step to reduce the liquid volume. As a result, the amount of liquid to be processed in the dewatering step can be smaller than the sum of the amount of primary slurry and the amount of secondary slurry, which contributes to the reduction of the above dewatering equipment.
２次分離ステップにおいて、２次清澄液への澱物の混入を抑えるためには、澱物をわずかでも含むスラリーは２次スラリーに分配させることが望ましい。この場合、２次スラリーは、スラリー濃度が低く且つ液量が多くなる。１次硫化工程へ繰り返されるスラリーがこのようにスラリー濃度が低く且つ液量が多ければ、１次硫化工程で処理すべき液量が多くなる。ただし、繰り返し先が１次分離ステップより前の工程であれば、１次分離ステップによって液量を低減できるため、１次脱水ステップへの影響は軽微である。 In the secondary separation step, in order to prevent the starch from being mixed into the secondary clarified liquid, it is desirable to distribute the slurry containing even a small amount of the starch into the secondary slurry. In this case, the secondary slurry has a low slurry concentration and a large liquid volume. If the slurry repeated to the primary sulfiding step has such a low slurry concentration and a large amount of liquid, the amount of liquid to be processed in the primary sulfiding step increases. However, if the repetition destination is a process before the primary separation step, the amount of liquid can be reduced by the primary separation step, so the influence on the primary dehydration step is negligible.
上記１次分離ステップ及び２次分離ステップにおいて濃縮により硫化澱物を適切に分離するためには、２次スラリーの量は１次スラリーの量に対して１０〜５０体積％であることが好ましい。１０％体積未満の場合には、１次スラリーが多くなるため脱水設備の負荷が大きくなるか、２次スラリーが少なくなり２次清澄液に硫化澱物が混入してしまう。逆に５０体積％を超える場合には、１次分離ステップに流入する液量が多くなるか１次スラリーが少なくなるため、１次清澄液に硫化澱物が混入し、石膏前濾過ステップの操業の手間やコストが増加したり、石膏製造工程で得られる石膏の品質が低下したりしてしまう。 In order to appropriately separate the sulfided starch by concentration in the primary separation step and the secondary separation step, the amount of the secondary slurry is preferably 10 to 50% by volume with respect to the amount of the primary slurry. If the volume is less than 10%, the amount of primary slurry increases, so the load on the dehydration equipment increases, or the secondary slurry decreases and sulfide starch is mixed into the secondary clarified liquid. On the other hand, when the volume exceeds 50% by volume, the amount of liquid flowing into the primary separation step increases or the primary slurry decreases, so that sulfurized starch is mixed in the primary clarified liquid and the pre-gypsum filtration step is started. This will increase the labor and cost and reduce the quality of gypsum obtained in the gypsum manufacturing process.
また、上記２次スラリーの量が１次スラリーの量に対して５０％を超える場合には、下記化学式１又は２の反応が生じて有毒の硫化水素が急激に発生するため、硫化水素除害設備の負荷が大きくなってしまうことから、工業的操業には適さない。 Further, when the amount of the secondary slurry exceeds 50% with respect to the amount of the primary slurry, the reaction of the following chemical formula 1 or 2 occurs, and toxic hydrogen sulfide is rapidly generated. Since the load on the equipment becomes large, it is not suitable for industrial operation.
［化学式１］
２ＮａＨＳ＋Ｈ２ＳＯ４ → ２Ｈ２Ｓ↑＋Ｎａ２ＳＯ４
［化学式２］
ＭＳ＋Ｈ２ＳＯ４ → Ｈ２Ｓ↑＋ＭＳＯ４
（式中のＭは２価の金属元素を表す）
[Chemical Formula 1]
2NaHS + H 2 SO 4 → 2H 2 S ↑ + Na 2 SO 4
[Chemical formula 2]
MS + H 2 SO 4 → H 2 S ↑ + MSO 4
(M in the formula represents a divalent metal element)
［実施例１］
重金属及び硫酸を含む廃酸を、３００ｌ／分の流量で１次硫化工程に送液した。１次硫化工程では、１次硫化反応槽にて廃酸に水硫化ナトリウムを添加することにより、ＯＲＰを１２０ｍＶにしてスラリーを得た。このスラリーを１次シックナーにて沈降濃縮し、上澄み液と底抜きとに分離した。この底抜きは貯液槽に溜めたあと、１次フィルタープレスで濾過することにより硫化澱物を回収した。
[Example 1]
Waste acid containing heavy metals and sulfuric acid was sent to the primary sulfiding step at a flow rate of 300 l / min. In the primary sulfiding step, sodium hydrosulfide was added to the waste acid in the primary sulfiding reaction tank to obtain an ORP of 120 mV to obtain a slurry. This slurry was concentrated by sedimentation with a primary thickener and separated into a supernatant and a bottom. The bottoms were collected in a liquid storage tank and then filtered with a primary filter press to recover sulfided starch.
一方、１次シックナーの上澄み液は、微細な粒子をフィルタープレスで濾過して除くことで石膏始液とし、石膏製造工程へ送液した。石膏製造工程では、石膏始液に炭酸カルシウムを添加してｐＨ２.３に調整し、得られたスラリーから固形分を取り除いて石膏を回収した。石膏を回収して残った石膏終液は、２次硫化工程へ送液した。 On the other hand, the supernatant liquid of the primary thickener was used as a gypsum starting liquid by filtering and removing fine particles with a filter press, and was sent to the gypsum manufacturing process. In the gypsum manufacturing process, calcium carbonate was added to the gypsum starting solution to adjust the pH to 2.3, and the solid content was removed from the resulting slurry to recover gypsum. The gypsum final solution remaining after collecting the gypsum was sent to the secondary sulfiding step.
２次硫化工程では、２次硫化反応槽にて石膏終液に水硫化ナトリウムを添加し、ＯＲＰが１０ｍＶとなるように調整してスラリーを得た。このスラリーを２次シックナーで沈降濃縮し、上澄み液と底抜きとに分離した。この底抜きは１次硫化工程に繰り返して、１次硫化反応槽に２０ｌ／分の流量で送液した。また、２次シックナーの上澄み液は排水処理工程に送液した。 In the secondary sulfidation step, sodium hydrosulfide was added to the gypsum final solution in a secondary sulfidation reaction tank to adjust the ORP to 10 mV to obtain a slurry. The slurry was concentrated by sedimentation with a secondary thickener and separated into a supernatant and a bottom. This bottoming was repeated in the primary sulfiding step, and the solution was fed to the primary sulfiding reaction tank at a flow rate of 20 l / min. The supernatant of the secondary thickener was sent to the wastewater treatment process.
上記の条件で１０日間にわたって操業を行ったところ、２次シックナーの底抜きが送液された１次硫化工程において、１次シックナーの上澄み液は清澄な状態が維持され、１次シックナーの底抜きは１００ｌ／分であって、１次シックナーと１次フィルタープレスの間の貯液槽から液が溢れることはなかった。また、１次シックナーの上澄み液を分析したところ、銅が１ｍｇ／ｌ及び砒素が１０ｍｇ／ｌであった。廃酸処理プロセス全体で使用した水硫化ナトリウムの量は、１日につき７.４トンであった。 When the operation was performed for 10 days under the above conditions, in the primary sulfidation process in which the bottom of the secondary thickener was fed, the supernatant of the primary thickener was maintained in a clear state, and the bottom of the primary thickener was maintained. Was 100 l / min, and no liquid overflowed from the reservoir between the primary thickener and the primary filter press. When the supernatant of the primary thickener was analyzed, it was found that copper was 1 mg / l and arsenic was 10 mg / l. The amount of sodium hydrosulfide used throughout the waste acid treatment process was 7.4 tons per day.
１次硫化工程及び２次硫化工程に要する作業員に関しては、１次フィルタープレスの監視と操作に作業員１人を要したが、石膏前フィルタープレスは１次シックナーの上澄み液が清澄で連続して通液できたので、作業員を配置する必要がなく、無人での運転が可能であった。従って、本発明による廃酸の処理方法では、監視と操作を要するフィルタープレスは１台のみで操業でき、脱水設備の監視や保守点検に要する作業を削減することができた。 Regarding the workers required for the primary sulfidation process and the secondary sulfidation process, one person was required to monitor and operate the primary filter press. However, the pre-gypsum filter press has a clear and continuous supernatant of the primary thickener. It was not necessary to place workers and the operation was unattended. Therefore, in the waste acid treatment method according to the present invention, only one filter press requiring monitoring and operation can be operated, and the work required for dehydration equipment monitoring and maintenance inspection can be reduced.
［比較例１］
２次シックナーの底抜きを１次硫化反応槽へ送液せず、従来と同様に２次フィルタープレスへ送液して濾過し、澱物を回収した以外は、上記実施例１と同様に実施した。
[Comparative Example 1]
The same as in Example 1 above, except that the bottom of the secondary thickener was not fed to the primary sulfidation reactor, but was fed to the secondary filter press and filtered to recover the starch. did.
上記の条件で１０日間にわたって操業を行ったところ、廃酸処理プロセス全体で使用する水硫化ナトリウムの量は１日につき８.１トンであった。また、１次フィルタープレスの監視と操作に作業員１人、及び２次フィルタープレスの監視と操作に作業員１人を要した。尚、石膏前フィルタープレスは、上記実施例１と同様に無人運転が可能であった。 When operated for 10 days under the above conditions, the amount of sodium hydrosulfide used in the entire waste acid treatment process was 8.1 tons per day. In addition, one worker was required for monitoring and operating the primary filter press, and one worker was required for monitoring and operating the secondary filter press. The pre-gypsum filter press was capable of unmanned operation as in Example 1 above.
実施例１と比較例１とでフィルタープレスの操業に要した人数を比較すると、実施例１では２次フィルタープレスを稼働せず、１次フィルタープレスでの１台のみの稼働で操業できたため、作業員を１名削減することができた。また、水硫化ナトリウムの使用量を比較すると、実施例１の方が少ない。この理由は、２次シックナーの底抜きには未反応の水硫化ナトリウムが含まれており且つその濃度は１次硫化工程よりも高いことから、実施例１では２次シックナーの底抜きを１次硫化工程へ繰り返すことで、未反応の水硫化ナトリウムが１次硫化工程で利用されたためである。 When comparing the number of persons required for the operation of the filter press in Example 1 and Comparative Example 1, in Example 1, the secondary filter press was not operated, and the operation was possible with only one operation in the primary filter press. The number of workers has been reduced by one. Moreover, when the usage-amount of sodium hydrosulfide is compared, Example 1 is smaller. This is because the bottom of the secondary thickener contains unreacted sodium hydrosulfide and the concentration thereof is higher than that of the primary sulfurization process. This is because unreacted sodium hydrosulfide was used in the primary sulfiding step by repeating the sulfiding step.
水硫化ナトリウムが還元剤として働く系において、その濃度が高いほどＯＲＰは低くなる。１次硫化工程のＯＲＰと２次硫化工程のＯＲＰは実施例１に記載の通りであり、２次硫化工程の方が１次硫化工程よりも常に低いことから、水硫化ナトリウム濃度は２次硫化工程の方が１次硫化工程よりも常に高かったことが見て取れる。 In a system in which sodium hydrosulfide works as a reducing agent, the higher the concentration, the lower the ORP. The ORP of the primary sulfidation step and the ORP of the secondary sulfidation step are as described in Example 1. The concentration of sodium hydrosulfide is secondary sulfidation because the secondary sulfidation step is always lower than the primary sulfidation step. It can be seen that the process was always higher than the primary sulfidation process.
上記実施例１においては、水硫化ナトリウム濃度の高いスラリーが２次硫化工程から１次硫化工程に送液されたので、実施例１の１次硫化工程の水硫化ナトリウム濃度が比較例１の１次硫化工程の水硫化ナトリウム濃度よりも部分的に高くなることが考えられる。水硫化ナトリウム濃度が高い場合、下記化学式３又は化学式４に基づいて重金属（銅や砒素）が沈殿し、１次シックナーの上澄み液中の重金属濃度が低くなる。 In Example 1 above, since the slurry having a high sodium hydrosulfide concentration was fed from the secondary sulfidation step to the primary sulfidation step, the sodium hydrosulfide concentration in the primary sulfidation step of Example 1 was 1 in Comparative Example 1. It may be partially higher than the sodium hydrosulfide concentration in the subsequent sulfidation step. When the sodium hydrosulfide concentration is high, heavy metals (copper and arsenic) precipitate based on the following chemical formula 3 or chemical formula 4, and the heavy metal concentration in the supernatant liquid of the primary thickener becomes low.
［化学式３］
２ＮａＨＳ＋ＣｕＳＯ４ → ２ＣｕＳ↓＋ＮａＨＳＯ４
［化学式４］
ＭＳ＋ＣｕＳＯ４ → ＣｕＳ↓＋ＭＳＯ４
（式中のＭは２価の金属元素を表す）
[Chemical formula 3]
2NaHS + CuSO 4 → 2CuS ↓ + NaHSO 4
[Chemical formula 4]
MS + CuSO 4 → CuS ↓ + MSO 4
(M in the formula represents a divalent metal element)
しかしながら、分析結果によれば、実施例１と比較例１の１次シックナーの上澄み液中の重金属濃度は等しかった。よって、水硫化ナトリウム濃度は実施例１と比較例１で等しかったことが分かる。このことは、本発明の方法によっても、水硫化ナトリウム濃度を適切に制御できることを示している。 However, according to the analysis results, the heavy metal concentrations in the supernatants of the primary thickeners of Example 1 and Comparative Example 1 were equal. Therefore, it can be seen that the sodium hydrosulfide concentration was equal in Example 1 and Comparative Example 1. This indicates that the sodium hydrosulfide concentration can be appropriately controlled also by the method of the present invention.
［比較例２］
２次シックナーの底抜きを１次硫化反応槽へ送液せず、その代りに１次シックナーの底抜きと１次フィルタープレスの間の貯液槽へ送液して濾過することにより澱物の回収を試みた以外は、上記実施例１と同様に実施した。
[Comparative Example 2]
The bottom of the secondary thickener is not fed to the primary sulfidation reactor, but instead is fed to the reservoir between the bottom of the primary thickener and the primary filter press and filtered to filter the starch. The same procedure as in Example 1 was performed except that recovery was attempted.
上記の条件で操業を行ったところ、１次シックナーの底抜きと１次フィルタープレスの間の貯液槽の保有液量が増加の一途を辿り、液が溢れそうになったため数時間で操業を中止した。 When the operation was performed under the above conditions, the amount of liquid held in the storage tank between the bottom of the primary thickener and the primary filter press continued to increase, and the liquid was about to overflow. Canceled.
Claims (7)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2014062926A JP6206287B2 (en) | 2014-03-26 | 2014-03-26 | Treatment method of waste acid generated in copper smelting |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2014062926A JP6206287B2 (en) | 2014-03-26 | 2014-03-26 | Treatment method of waste acid generated in copper smelting |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JP2015182052A true JP2015182052A (en) | 2015-10-22 |
| JP6206287B2 JP6206287B2 (en) | 2017-10-04 |
Family
ID=54349239
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2014062926A Active JP6206287B2 (en) | 2014-03-26 | 2014-03-26 | Treatment method of waste acid generated in copper smelting |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP6206287B2 (en) |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107399855A (en) * | 2017-08-25 | 2017-11-28 | 金川集团股份有限公司 | A kind of system and method for handling metallurgical off-gas acid-making acid waste water |
| JP2017213507A (en) * | 2016-05-31 | 2017-12-07 | 住友金属鉱山株式会社 | Waste acid treatment method |
| CN107445379A (en) * | 2017-08-25 | 2017-12-08 | 金川集团股份有限公司 | A kind of device and method of acid waste water evaporation emission reduction |
| JP2019002046A (en) * | 2017-06-15 | 2019-01-10 | 住友金属鉱山株式会社 | Treatment method of waste acid |
| JP2019063781A (en) * | 2017-10-05 | 2019-04-25 | 住友金属鉱山株式会社 | Treatment method of waste acid generated in copper smelting |
| KR102283027B1 (en) * | 2020-12-28 | 2021-07-28 | 한국광해관리공단 | METHOD OF Cu RECOVERY FROM LEACHATE AFTER Cu EXTRACTION |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP6970917B2 (en) | 2017-12-27 | 2021-11-24 | 三菱マテリアル株式会社 | Wastewater treatment method |
| JP6986226B2 (en) | 2017-12-27 | 2021-12-22 | 三菱マテリアル株式会社 | Wastewater treatment method |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2004275895A (en) * | 2003-03-17 | 2004-10-07 | Sumitomo Metal Mining Co Ltd | Method for treating exhaust gas from sulfuric acid manufacturing process |
| JP2005154196A (en) * | 2003-11-26 | 2005-06-16 | Sumitomo Metal Mining Co Ltd | Method for producing waste acid gypsum |
| JP2005350766A (en) * | 2004-05-13 | 2005-12-22 | Sumitomo Metal Mining Co Ltd | Hydrometallurgical process of nickel oxide ore |
| JP2012012230A (en) * | 2010-06-29 | 2012-01-19 | Pan Pacific Copper Co Ltd | Method for producing waste acid gypsum |
| JP2015020103A (en) * | 2013-07-18 | 2015-02-02 | 住友金属鉱山株式会社 | Method for removing heavy metal |
-
2014
- 2014-03-26 JP JP2014062926A patent/JP6206287B2/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2004275895A (en) * | 2003-03-17 | 2004-10-07 | Sumitomo Metal Mining Co Ltd | Method for treating exhaust gas from sulfuric acid manufacturing process |
| JP2005154196A (en) * | 2003-11-26 | 2005-06-16 | Sumitomo Metal Mining Co Ltd | Method for producing waste acid gypsum |
| JP2005350766A (en) * | 2004-05-13 | 2005-12-22 | Sumitomo Metal Mining Co Ltd | Hydrometallurgical process of nickel oxide ore |
| JP2012012230A (en) * | 2010-06-29 | 2012-01-19 | Pan Pacific Copper Co Ltd | Method for producing waste acid gypsum |
| JP2015020103A (en) * | 2013-07-18 | 2015-02-02 | 住友金属鉱山株式会社 | Method for removing heavy metal |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2017213507A (en) * | 2016-05-31 | 2017-12-07 | 住友金属鉱山株式会社 | Waste acid treatment method |
| JP2019002046A (en) * | 2017-06-15 | 2019-01-10 | 住友金属鉱山株式会社 | Treatment method of waste acid |
| CN107399855A (en) * | 2017-08-25 | 2017-11-28 | 金川集团股份有限公司 | A kind of system and method for handling metallurgical off-gas acid-making acid waste water |
| CN107445379A (en) * | 2017-08-25 | 2017-12-08 | 金川集团股份有限公司 | A kind of device and method of acid waste water evaporation emission reduction |
| JP2019063781A (en) * | 2017-10-05 | 2019-04-25 | 住友金属鉱山株式会社 | Treatment method of waste acid generated in copper smelting |
| JP7031207B2 (en) | 2017-10-05 | 2022-03-08 | 住友金属鉱山株式会社 | Treatment method of waste acid generated in copper smelting |
| KR102283027B1 (en) * | 2020-12-28 | 2021-07-28 | 한국광해관리공단 | METHOD OF Cu RECOVERY FROM LEACHATE AFTER Cu EXTRACTION |
Also Published As
| Publication number | Publication date |
|---|---|
| JP6206287B2 (en) | 2017-10-04 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP6206287B2 (en) | Treatment method of waste acid generated in copper smelting | |
| US7789944B2 (en) | System and method for treating dust contained in extracted cement kiln combustion gas | |
| US8603344B2 (en) | Method and apparatus for removing metal from waste water | |
| JP6743491B2 (en) | Waste acid treatment method | |
| US7264733B2 (en) | Method for treating heavy-metal-containing wastewater using sulfidizing agent | |
| KR102556133B1 (en) | Wastewater Treatment Method | |
| JP5355431B2 (en) | Method and apparatus for treating incinerated fly ash and cement kiln combustion gas bleed dust | |
| JP3306471B2 (en) | Treatment method of exhaust gas from cement kiln | |
| JP6481542B2 (en) | Method for producing high-purity nickel sulfate aqueous solution | |
| JP2012082458A (en) | Method for separating and recovering zinc from zinc plating waste liquid | |
| CN106517624B (en) | Desulfurization wastewater treatment method and system based on multistage fluidized bed crystallization | |
| JP6953988B2 (en) | How to remove sulfide | |
| JP4986958B2 (en) | Water washing method and water washing system for incineration ash and cement kiln combustion gas extraction dust | |
| EA004600B1 (en) | Process for electrolytic production of highly pure zinc or zinc compounds from primary and secondary zinc raw material | |
| JP5911100B2 (en) | Wastewater treatment method | |
| RU2443791C1 (en) | Conditioning method of cyanide-containing reusable solutions for processing of gold-copper ores with extraction of gold and copper and regeneration of cyanide | |
| JP3945216B2 (en) | Waste acid gypsum manufacturing method | |
| JP6962017B2 (en) | Waste acid treatment method | |
| CN105330064A (en) | Zinc-containing cyanide barren solution treatment method | |
| JP4239801B2 (en) | Method for producing waste acid gypsum | |
| US4012297A (en) | Mercury recovery and recycle process | |
| RU2448053C1 (en) | Apparatus for purifying alkaline wastes | |
| WO2005012582A1 (en) | Improved hydrometallurgical processing of manganese containing materials | |
| JP2008075139A (en) | Method for treating dust in bled combustion gas of cement kiln | |
| JP7031207B2 (en) | Treatment method of waste acid generated in copper smelting |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A621 | Written request for application examination |
Free format text: JAPANESE INTERMEDIATE CODE: A621 Effective date: 20160714 |
|
| A977 | Report on retrieval |
Free format text: JAPANESE INTERMEDIATE CODE: A971007 Effective date: 20170425 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20170509 |
|
| A521 | Request for written amendment filed |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20170621 |
|
| TRDD | Decision of grant or rejection written | ||
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 20170808 |
|
| A61 | First payment of annual fees (during grant procedure) |
Free format text: JAPANESE INTERMEDIATE CODE: A61 Effective date: 20170821 |
|
| R150 | Certificate of patent or registration of utility model |
Ref document number: 6206287 Country of ref document: JP Free format text: JAPANESE INTERMEDIATE CODE: R150 |