JP4734643B2 - Method for removing heavy metals from scallop visceral waste - Google Patents
Method for removing heavy metals from scallop visceral waste Download PDFInfo
- Publication number
- JP4734643B2 JP4734643B2 JP2006054267A JP2006054267A JP4734643B2 JP 4734643 B2 JP4734643 B2 JP 4734643B2 JP 2006054267 A JP2006054267 A JP 2006054267A JP 2006054267 A JP2006054267 A JP 2006054267A JP 4734643 B2 JP4734643 B2 JP 4734643B2
- Authority
- JP
- Japan
- Prior art keywords
- tank
- heavy metals
- uro
- sulfuric acid
- flocculant
- 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.)
- Active
Links
- 229910001385 heavy metal Inorganic materials 0.000 title claims description 62
- 238000000034 method Methods 0.000 title claims description 41
- 235000020637 scallop Nutrition 0.000 title claims description 18
- 239000002699 waste material Substances 0.000 title claims description 16
- 230000009278 visceral effect Effects 0.000 title claims description 9
- 241000237509 Patinopecten sp. Species 0.000 title description 9
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 claims description 62
- 102000004169 proteins and genes Human genes 0.000 claims description 33
- 108090000623 proteins and genes Proteins 0.000 claims description 33
- 238000002386 leaching Methods 0.000 claims description 27
- 239000007788 liquid Substances 0.000 claims description 25
- 239000007864 aqueous solution Substances 0.000 claims description 24
- 239000000243 solution Substances 0.000 claims description 19
- 238000007654 immersion Methods 0.000 claims description 16
- 210000002700 urine Anatomy 0.000 claims description 16
- 150000002632 lipids Chemical class 0.000 claims description 12
- 238000001179 sorption measurement Methods 0.000 claims description 12
- 238000000926 separation method Methods 0.000 claims description 11
- 241000237503 Pectinidae Species 0.000 claims description 9
- 238000005342 ion exchange Methods 0.000 claims description 8
- 238000001556 precipitation Methods 0.000 claims description 8
- 238000011084 recovery Methods 0.000 claims description 5
- 125000005500 uronium group Chemical group 0.000 claims 3
- 229910052793 cadmium Inorganic materials 0.000 description 31
- BDOSMKKIYDKNTQ-UHFFFAOYSA-N cadmium atom Chemical compound [Cd] BDOSMKKIYDKNTQ-UHFFFAOYSA-N 0.000 description 31
- 239000003925 fat Substances 0.000 description 17
- 238000005363 electrowinning Methods 0.000 description 14
- 235000011511 Diospyros Nutrition 0.000 description 12
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 12
- 244000236655 Diospyros kaki Species 0.000 description 11
- 230000004931 aggregating effect Effects 0.000 description 11
- 239000003795 chemical substances by application Substances 0.000 description 10
- 238000001914 filtration Methods 0.000 description 9
- 239000003337 fertilizer Substances 0.000 description 8
- 229910052751 metal Inorganic materials 0.000 description 7
- 239000002184 metal Substances 0.000 description 7
- 239000002253 acid Substances 0.000 description 6
- KRKNYBCHXYNGOX-UHFFFAOYSA-N citric acid Chemical compound OC(=O)CC(O)(C(O)=O)CC(O)=O KRKNYBCHXYNGOX-UHFFFAOYSA-N 0.000 description 6
- 230000002776 aggregation Effects 0.000 description 5
- 238000005516 engineering process Methods 0.000 description 5
- 239000000706 filtrate Substances 0.000 description 5
- 239000011347 resin Substances 0.000 description 5
- 229920005989 resin Polymers 0.000 description 5
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 4
- NBIIXXVUZAFLBC-UHFFFAOYSA-N Phosphoric acid Chemical compound OP(O)(O)=O NBIIXXVUZAFLBC-UHFFFAOYSA-N 0.000 description 4
- 238000004220 aggregation Methods 0.000 description 4
- 239000011260 aqueous acid Substances 0.000 description 4
- 238000007598 dipping method Methods 0.000 description 4
- 238000012545 processing Methods 0.000 description 4
- 238000002791 soaking Methods 0.000 description 4
- 235000011121 sodium hydroxide Nutrition 0.000 description 4
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 4
- 239000013522 chelant Substances 0.000 description 3
- 238000004064 recycling Methods 0.000 description 3
- 238000011160 research Methods 0.000 description 3
- 239000000126 substance Substances 0.000 description 3
- 210000001835 viscera Anatomy 0.000 description 3
- BJEPYKJPYRNKOW-REOHCLBHSA-N (S)-malic acid Chemical compound OC(=O)[C@@H](O)CC(O)=O BJEPYKJPYRNKOW-REOHCLBHSA-N 0.000 description 2
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 description 2
- 230000004523 agglutinating effect Effects 0.000 description 2
- BJEPYKJPYRNKOW-UHFFFAOYSA-N alpha-hydroxysuccinic acid Natural products OC(=O)C(O)CC(O)=O BJEPYKJPYRNKOW-UHFFFAOYSA-N 0.000 description 2
- 229910000147 aluminium phosphate Inorganic materials 0.000 description 2
- AXCZMVOFGPJBDE-UHFFFAOYSA-L calcium dihydroxide Chemical compound [OH-].[OH-].[Ca+2] AXCZMVOFGPJBDE-UHFFFAOYSA-L 0.000 description 2
- 239000000920 calcium hydroxide Substances 0.000 description 2
- 229910001861 calcium hydroxide Inorganic materials 0.000 description 2
- 125000003178 carboxy group Chemical group [H]OC(*)=O 0.000 description 2
- 238000011161 development Methods 0.000 description 2
- 230000018109 developmental process Effects 0.000 description 2
- 230000007613 environmental effect Effects 0.000 description 2
- 235000011389 fruit/vegetable juice Nutrition 0.000 description 2
- 210000000514 hepatopancreas Anatomy 0.000 description 2
- 238000009854 hydrometallurgy Methods 0.000 description 2
- 239000003456 ion exchange resin Substances 0.000 description 2
- 229920003303 ion-exchange polymer Polymers 0.000 description 2
- 239000001630 malic acid Substances 0.000 description 2
- 235000011090 malic acid Nutrition 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 150000002739 metals Chemical class 0.000 description 2
- 229910017604 nitric acid Inorganic materials 0.000 description 2
- 150000007524 organic acids Chemical class 0.000 description 2
- 235000005985 organic acids Nutrition 0.000 description 2
- 239000002244 precipitate Substances 0.000 description 2
- 239000002994 raw material Substances 0.000 description 2
- 229920001864 tannin Polymers 0.000 description 2
- 239000001648 tannin Substances 0.000 description 2
- 235000018553 tannin Nutrition 0.000 description 2
- NWUYHJFMYQTDRP-UHFFFAOYSA-N 1,2-bis(ethenyl)benzene;1-ethenyl-2-ethylbenzene;styrene Chemical compound C=CC1=CC=CC=C1.CCC1=CC=CC=C1C=C.C=CC1=CC=CC=C1C=C NWUYHJFMYQTDRP-UHFFFAOYSA-N 0.000 description 1
- OYPRJOBELJOOCE-UHFFFAOYSA-N Calcium Chemical compound [Ca] OYPRJOBELJOOCE-UHFFFAOYSA-N 0.000 description 1
- 241000207199 Citrus Species 0.000 description 1
- 241001672694 Citrus reticulata Species 0.000 description 1
- 244000055850 Diospyros virginiana Species 0.000 description 1
- -1 EPA and DHA Chemical class 0.000 description 1
- CWYNVVGOOAEACU-UHFFFAOYSA-N Fe2+ Chemical compound [Fe+2] CWYNVVGOOAEACU-UHFFFAOYSA-N 0.000 description 1
- VTLYFUHAOXGGBS-UHFFFAOYSA-N Fe3+ Chemical compound [Fe+3] VTLYFUHAOXGGBS-UHFFFAOYSA-N 0.000 description 1
- 240000000599 Lentinula edodes Species 0.000 description 1
- 235000001715 Lentinula edodes Nutrition 0.000 description 1
- 240000007594 Oryza sativa Species 0.000 description 1
- 235000007164 Oryza sativa Nutrition 0.000 description 1
- OAICVXFJPJFONN-UHFFFAOYSA-N Phosphorus Chemical compound [P] OAICVXFJPJFONN-UHFFFAOYSA-N 0.000 description 1
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 description 1
- 238000010521 absorption reaction Methods 0.000 description 1
- 239000003463 adsorbent Substances 0.000 description 1
- 238000005054 agglomeration Methods 0.000 description 1
- 230000032683 aging Effects 0.000 description 1
- 239000003513 alkali Substances 0.000 description 1
- 150000001413 amino acids Chemical class 0.000 description 1
- QZPSXPBJTPJTSZ-UHFFFAOYSA-N aqua regia Chemical compound Cl.O[N+]([O-])=O QZPSXPBJTPJTSZ-UHFFFAOYSA-N 0.000 description 1
- 239000003212 astringent agent Substances 0.000 description 1
- 231100000704 bioconcentration Toxicity 0.000 description 1
- 230000000903 blocking effect Effects 0.000 description 1
- PLLZRTNVEXYBNA-UHFFFAOYSA-L cadmium hydroxide Chemical compound [OH-].[OH-].[Cd+2] PLLZRTNVEXYBNA-UHFFFAOYSA-L 0.000 description 1
- 239000011575 calcium Substances 0.000 description 1
- 229910052791 calcium Inorganic materials 0.000 description 1
- 238000005341 cation exchange Methods 0.000 description 1
- 150000001768 cations Chemical class 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 235000020971 citrus fruits Nutrition 0.000 description 1
- 239000012141 concentrate Substances 0.000 description 1
- 229920002770 condensed tannin Polymers 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 235000014113 dietary fatty acids Nutrition 0.000 description 1
- 238000010828 elution Methods 0.000 description 1
- 238000003912 environmental pollution Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 210000000416 exudates and transudate Anatomy 0.000 description 1
- 239000000194 fatty acid Substances 0.000 description 1
- 229930195729 fatty acid Natural products 0.000 description 1
- 150000004665 fatty acids Chemical class 0.000 description 1
- 229910001447 ferric ion Inorganic materials 0.000 description 1
- 239000002920 hazardous waste Substances 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 238000006460 hydrolysis reaction Methods 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-M hydroxide Chemical compound [OH-] XLYOFNOQVPJJNP-UHFFFAOYSA-M 0.000 description 1
- 150000004679 hydroxides Chemical class 0.000 description 1
- 229910052500 inorganic mineral Inorganic materials 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000011707 mineral Substances 0.000 description 1
- 235000010755 mineral Nutrition 0.000 description 1
- 150000007522 mineralic acids Chemical class 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 235000015205 orange juice Nutrition 0.000 description 1
- 239000011574 phosphorus Substances 0.000 description 1
- 229910052698 phosphorus Inorganic materials 0.000 description 1
- 231100000572 poisoning Toxicity 0.000 description 1
- 230000000607 poisoning effect Effects 0.000 description 1
- 239000011148 porous material Substances 0.000 description 1
- 239000000047 product Substances 0.000 description 1
- 235000009566 rice Nutrition 0.000 description 1
- 239000013535 sea water Substances 0.000 description 1
- 230000001954 sterilising effect Effects 0.000 description 1
- 238000004659 sterilization and disinfection Methods 0.000 description 1
- 125000004434 sulfur atom Chemical group 0.000 description 1
- 229910052725 zinc Inorganic materials 0.000 description 1
- 239000011701 zinc Substances 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
- Y02A—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
- Y02A40/00—Adaptation technologies in agriculture, forestry, livestock or agroalimentary production
- Y02A40/10—Adaptation technologies in agriculture, forestry, livestock or agroalimentary production in agriculture
- Y02A40/20—Fertilizers of biological origin, e.g. guano or fertilizers made from animal corpses
-
- 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
- Processing Of Solid Wastes (AREA)
- Separation Of Suspended Particles By Flocculating Agents (AREA)
- Fertilizers (AREA)
- Manufacture And Refinement Of Metals (AREA)
- Electrolytic Production Of Metals (AREA)
Description
本発明は、ホタテ貝の内臓廃棄物中よりカドミウム等の重金属を除去することにより、当該重金属およびホタテ貝内臓廃棄物を有効利用する技術に関するものである。 The present invention relates to a technique for effectively utilizing heavy metals and scallop visceral waste by removing heavy metals such as cadmium from scallop visceral waste.
現在ホタテ貝(帆立貝)の養殖は北海道や青森県を代表する産業となっているが、加工工程で発生する貝殻や中腸腺等の軟体部分の廃棄物の処理が大きな課題となっている(なお、このようなホタテ貝の内臓廃棄物は、通称、ウロと呼ばれており、本願の明細書、請求の範囲、図面および要約書においても、ホタテ貝の内臓廃棄物を単にウロと称することがある)。 Currently, scallops (scallops) are cultivated in industries such as Hokkaido and Aomori Prefecture, but the disposal of waste from soft parts such as shells and midgut glands generated during processing is a major issue ( Such scallop visceral waste is commonly referred to as uro, and scallop visceral waste is simply referred to as uro in the specification, claims, drawings and abstract of the present application. There).
以前はこれらのウロは海洋投棄されていたが、ロンドン条約の批准に伴い海洋投棄は禁止され、コストを要する陸上処理をする必要が生じた。ウロの廃棄物は一方では良質のタンパク質、アミノ酸、脂肪、EPAやDHA等の高機能の脂肪酸、燐やカルシウム等のミネラル分を豊富に含んでおり、処理方法次第で良質の肥料や飼料として高い利用価値が期待できる。しかしながらウロには生物濃縮により海水由来のカドミウム等の重金属が比較的高濃度で含まれており、これがウロの廃棄物の有効利用を阻んでいる。
青森県や北海道のオホーツク海沿岸ではウロが焼却処分されているが、この方法では焼却コストが嵩む他、重金属を含む焼却残渣の処理等の新たな問題も発生している。これに対して北海道では道立工業試験場を中心とした研究機関により平成3年より8年間の歳月をかけて硫酸浸出―電解採取によるカドミウムの除去技術が開発された(非特許文献1:作田庸一、嶋影和宣:湿式精錬プロセスによる水産系廃棄物(ホタテウロ)のリサイクル技術の開発、資源と素材、第120巻、第2号、pp.71−77(2004))。
Previously, these uros were dumped into the ocean, but with the ratification of the London Convention, ocean dumping was banned, requiring costly land treatment. Our waste, on the other hand, is rich in high-quality proteins, amino acids, fats, high-functional fatty acids such as EPA and DHA, and minerals such as phosphorus and calcium. Use value can be expected. However, urine contains relatively high concentrations of heavy metals such as cadmium derived from seawater due to bioconcentration, which hinders the effective use of urine waste.
Uro is incinerated on the coast of the Sea of Okhotsk in Aomori Prefecture and Hokkaido, but this method raises the cost of incineration and creates new problems such as the disposal of incineration residues containing heavy metals. On the other hand, in Hokkaido, a technology for removing cadmium by sulfuric acid leaching and electrowinning has been developed over 8 years since 1991 by a research institution centered on the Provincial Industrial Research Institute (Non-patent Document 1: Sakuta). Shinichi, Kagenobu Shimakage: Development of marine waste (scallopuro) recycling technology by hydrometallurgical process, resources and materials, Vol. 120, No. 2, pp. 71-77 (2004)).
この技術に基づく処理施設が北海道の砂原町(平成17年の合併により現在は森町)で現在稼動している。ここではボイルされたウロを3%の希硫酸水溶液中(pH=0.7)に浸漬させることによりカドミウムを浸出させ、これを電解採取した後、5%の硫酸水溶液中に再度溶解させ、最終的に水酸化ナトリウムの添加により水酸化カドミウムの沈殿として回収されている。 A processing facility based on this technology is currently operating in Sunahara-cho, Hokkaido (currently Mori-machi after the merger in 2005). Here, the cadmium was leached by immersing the boiled urine in a 3% dilute sulfuric acid aqueous solution (pH = 0.7), and this was electrolyzed and then dissolved again in a 5% aqueous sulfuric acid solution. In particular, it is recovered as a cadmium hydroxide precipitate by the addition of sodium hydroxide.
ウロの浸漬液中には高濃度のタンパク質や脂肪が溶解しており、これが電解採取の効率を著しく悪化させている。電解採取によりカドミウムを効率的に除去するためには、電解採取に先立ってこのような高濃度のタンパク質や脂肪(脂質)を除去しておくことが望まれる。また電解採取においては浸出液中のカドミウムの濃度が数ppmと希薄なため、多大な電力を要するという問題がある。電解採取を効率的に行うためには、低濃度のカドミウムをイオン交換樹脂やキレート樹脂を用いて吸着・溶離することにより電解採取に適した濃度まで濃縮することが望ましい。しかし多孔性のイオン交換樹脂やキレート樹脂では、ウロの浸漬液中の高濃度のタンパク質や脂肪が樹脂の細孔を塞ぐことにより被毒が起こり樹脂の機能を著しく低下させるという致命的な問題点がある。 High concentrations of protein and fat are dissolved in the immersion liquid of uro, which significantly deteriorates the efficiency of electrowinning. In order to efficiently remove cadmium by electrowinning, it is desirable to remove such high-concentration proteins and fats (lipids) prior to electrowinning. Moreover, in the electrowinning, the concentration of cadmium in the leachate is a few ppm, so there is a problem that a great amount of power is required. In order to perform electrowinning efficiently, it is desirable to concentrate cadmium at a low concentration to an appropriate concentration for electrowinning by adsorption and elution using an ion exchange resin or a chelate resin. However, in the case of porous ion exchange resins and chelate resins, a fatal problem is that poisoning occurs due to the high concentration of protein or fat in the immersion liquid of uro blocking the pores of the resin and the function of the resin is significantly reduced. There is.
本発明者らは以前の研究でこれら合成の多孔性樹脂の替わりにミカン搾汁残渣を用いてカドミウムを吸着・濃縮するプロセスを提案した(特許文献1:特開2005−058951「ホタテ貝内臓浸漬液中の重金属および脂肪とタンパク質の分離・除去・濃縮・回収方法」(平成17年3月10日公開))。しかしながらこのプロセスにおいても以下の問題点がある。すなわち、ミカン搾汁残渣の吸着剤では鉛や第2鉄イオン等の陽イオンはpH=2程度の低いpHで吸着が起こるが、カドミウムの吸着が起こるpHは比較的高く、十分な吸着を起こすためにはpHを6程度にまで上げる必要がある。硫酸を用いて得られたpHが1以下の浸漬液のpHを6程度まで上げるためには水酸化ナトリウム等のアルカリを多量に添加する必要があり、大きなコストを要する。 In the previous study, the present inventors proposed a process for adsorbing and concentrating cadmium using mandarin orange juice residue instead of these synthetic porous resins (Patent Document 1: Japanese Patent Application Laid-Open No. 2005-058951 “Scallop visceral soaking). Separation / removal / concentration / recovery method of heavy metals and fats and proteins in liquid ”(published on March 10, 2005)). However, this process also has the following problems. That is, in adsorbents of citrus juice residue, cations such as lead and ferric ions are adsorbed at a pH as low as about pH = 2, but the pH at which cadmium is adsorbed is relatively high and causes sufficient adsorption. In order to achieve this, it is necessary to raise the pH to about 6. In order to raise the pH of the immersion liquid obtained using sulfuric acid to 1 or less to about 6, it is necessary to add a large amount of alkali such as sodium hydroxide, which requires a large cost.
ウロ中の重金属を除去するためには、上述のように、希硫酸等の酸水溶液中に浸漬することにより重金属を浸出させるとともに、このようにして水溶液中に浸出させた重金属を経済的に分離・回収する、または環境中への漏出の防止にために固定化することが必要である。重金属の分離・回収方法としては、(1)イオン交換、吸着法あるいは沈殿法、または、(2)電解採取法の2つの方法が考えられるが、現行の技術では、下記のように、これらの方法を有効に活用することができない。 In order to remove heavy metals in urine, as described above, heavy metals are leached by immersing them in an acid aqueous solution such as dilute sulfuric acid, and the heavy metals leached in the aqueous solution in this way are economically separated. -It must be fixed for recovery or to prevent leakage into the environment. There are two methods for separating and recovering heavy metals: (1) ion exchange, adsorption method or precipitation method, or (2) electrowinning method. The method cannot be used effectively.
イオン交換、吸着法あるいは沈殿法による重金属の分離においては、水溶液のpHをそれらに適したpHに設定することが必要となる。ウロからの重金属の浸出には低いpHの酸水溶液が効果的であるのに対し、浸出された重金属の分離には高いpHの液が好ましい。このため液のpHを上げるためには苛性ソーダや水酸化カルシウム等のアルカリの添加が必要となるが、それには多大のコストを伴う。さらにウロを酸水溶液中に浸漬した場合、大量のタンパク質や脂肪等の溶出が起こるが、これらは重金属の分離を著しく阻害するため、当該水溶液からの重金属の分離は容易ではない。
また、現行の電解採取法により重金属を除去する場合においても、既述のように、pHの低い浸漬液から大量のタンパク質や脂質を予め除去しておくなど、電解採取が効率的に実施できるための手段は未だ充分に確立されていない。
In addition, even when heavy metals are removed by the current electrolytic collection method, as described above, it is possible to efficiently perform electrolytic collection, such as removing a large amount of proteins and lipids from a low pH immersion liquid in advance. This means is not yet well established.
本発明の目的は、ウロからカドミウム等の重金属を効率的且つ経済的に除去して、それらの重金属やウロ中の成分の有効利用を図ることができるような新しい技術を提供することにある。 An object of the present invention is to provide a new technique capable of efficiently and economically removing heavy metals such as cadmium from uro and effectively utilizing those heavy metals and components in uro.
本発明者らは、研究を重ねた結果、ウロの硫酸浸出液から、ウロ中のタンパク質や脂質を効率的に凝集させることのできる凝集剤を見出し本発明を導き出した。
かくして、本発明は、ホタテ貝の内臓廃棄物(ウロ)を硫酸水溶液に浸漬して、ウロ中の重金属を硫酸水溶液中に浸出させる工程、および前記浸漬工程後の浸出液に凝集剤を添加してウロ中のタンパク質および脂質を凝集除去する工程を含むことを特徴とするウロから重金属を除去する方法を提供するものである。本発明の特に好ましい態様に従えば、凝集剤は、柿渋より製造された凝集剤である。
As a result of repeated research, the present inventors have found an aggregating agent capable of efficiently aggregating proteins and lipids in uro from the sulfuric acid leachate of uro, and have derived the present invention.
Thus, the present invention includes a step of immersing scallop visceral waste (uro) in a sulfuric acid aqueous solution, leaching heavy metals in uro into the sulfuric acid aqueous solution, and adding a flocculant to the exudate after the immersion step. The present invention provides a method for removing heavy metals from uro, comprising the step of aggregating and removing proteins and lipids in uro. According to a particularly preferred embodiment of the present invention, the flocculant is a flocculant produced from amber astringent.
本発明により提供される技術を用いればウロから重金属が除去されることにより、難処理廃棄物のウロが良質の肥料や飼料として有効利用することができる。また浸出液中に高濃度で溶出されたタンパク質や脂肪なども柿渋由来のものに代表される凝集剤により分離・回収され、ウロ自体と同様に良質の肥料や飼料として有効利用することができる。さらに回収された重金属は非鉄金属の製錬所に中間原料として販売可能である。 If the technique provided by the present invention is used, heavy metal is removed from the scale, so that the scale-resistant waste scale can be effectively used as a high-quality fertilizer and feed. In addition, proteins and fats eluted at high concentrations in the leachate are separated and recovered by a flocculant represented by those derived from persimmon astringents, and can be used effectively as high-quality fertilizers and feeds, just like uro itself. Furthermore, the recovered heavy metals can be sold as intermediate raw materials to non-ferrous metal smelters.
ウロ中の重金属はウロに含まれるタンパク質末端のカルボキシル基、ならびに同じタンパク質の窒素原子や硫黄原子が配位した金属キレートとして存在していると考えられる。ウロのタンパク質からこのような重金属を遊離させるためには、カルボキシル基の陽イオン交換反応を利用して、酸水溶液と接触させることが必要である。酸水溶液としては硫酸、塩酸、硝酸、燐酸などの無機酸やクエン酸、リンゴ酸などの有機酸が考えられる。この内、クエン酸、リンゴ酸などの有機酸は重金属の強力な浸出剤として働くが、後の浸出液からの金属の分離に障害を与える。さらに塩酸は装置を腐食させ、硝酸や燐酸は環境汚染を引き起こす。これに対して硫酸は安価で環境に対する負荷も少ないため、浸出液として最適である。 The heavy metal in uro is considered to exist as a metal chelate in which the carboxyl group at the end of the protein contained in uro and the nitrogen and sulfur atoms of the same protein are coordinated. In order to release such heavy metals from uroproteins, it is necessary to make contact with an aqueous acid solution by utilizing a cation exchange reaction of a carboxyl group. Examples of the acid aqueous solution include inorganic acids such as sulfuric acid, hydrochloric acid, nitric acid, and phosphoric acid, and organic acids such as citric acid and malic acid. Among these, organic acids such as citric acid and malic acid act as a strong leaching agent for heavy metals, but hinder the separation of metals from the later leachate. Furthermore, hydrochloric acid corrodes the equipment, and nitric acid and phosphoric acid cause environmental pollution. On the other hand, sulfuric acid is inexpensive and has a low environmental impact, so it is optimal as a leachate.
このように、ウロからの金属の浸出には低いpH、すなわちより高濃度の酸水溶液(硫酸水溶液)が好ましい。そして、硫酸水溶液で浸出を行うとウロから大量のタンパク質や脂質も同時に水溶液中に溶出し、浸漬液はコロイド状になっている。本発明においては、コロイド状で低pHの液中においてタンパク質および脂質に対する凝集能を有する凝集剤を用いて、ウロ中のタンパク質および脂質を凝集除去する。凝集剤としては、生化学の分野等においてタンパク質や脂質を凝集させる目的で使用されている各種の凝集剤が使用可能である。但し、水処理で広く使用されている合成の凝集剤は、一般に、上記のようなコロイド状の低いpHの液に対しては凝集機能を発現せず、また、溶出したタンパク質や脂質を後に肥料や飼料として利用する観点からも好ましくない。 Thus, a low pH, that is, a higher concentration aqueous acid solution (sulfuric acid aqueous solution) is preferable for leaching of metal from uro. When leaching is performed with an aqueous sulfuric acid solution, a large amount of proteins and lipids are simultaneously eluted from the urine into the aqueous solution, and the immersion liquid is colloidal. In the present invention, proteins and lipids in uro are aggregated and removed using an aggregating agent that has the ability to aggregate proteins and lipids in a colloidal and low pH solution. As the aggregating agent, various aggregating agents used for the purpose of aggregating proteins and lipids in the field of biochemistry and the like can be used. However, a synthetic flocculant widely used in water treatment generally does not exhibit an aggregating function with respect to the colloidal low pH liquid as described above, and the eluted protein or lipid is later used as a fertilizer. It is also not preferable from the viewpoint of use as feed.
本発明者らは、本発明において用いられる凝集剤として柿渋より製造された凝集剤が特に適していることを見出した。柿渋から成る凝集剤は清酒中の米由来のタンパク質を分離・除去するために古来より使用されてきた天然の凝集剤であり、その安全性も確立されている。よく知られているように、柿渋は、水分、糖分、柿タンニンなどからなり、主成分である柿タンニンは、水の作用で縮合して高分子物質となる縮合型タンニンの一つである。本発明に適用する柿渋由来の凝集剤としては市販品をそのまま用いるのが便利である(例えば、株式会社トミヤマから吟醸玉渋無菌の名で販売されているものを使用することができる)が、必要に応じて、調製することもできる。柿渋の凝集剤の製造は、一般に、手作業または機械を用いて柿渋を搾汁する工程、およびその後の熟成工程から成る。柿渋凝集剤の使用濃度や浸出液に対する添加比率などは、適用する柿渋凝集剤に応じて実験により簡単に定めることができる。例えば、上記の(株)トミヤマ製の柿渋凝集剤は、一般に、10%水溶液として使用する(後述の実施例参照)。 The present inventors have found that an aggregating agent manufactured from Kashiwabu is particularly suitable as the aggregating agent used in the present invention. The flocculant composed of persimmon is a natural flocculant that has been used since ancient times to separate and remove rice-derived proteins in sake, and its safety has been established. As is well known, persimmon astringent consists of water, sugar, persimmon tannin, and the like. Persimmon tannin, which is the main component, is one of condensed tannins that are condensed by the action of water to become a high molecular weight substance. It is convenient to use a commercially available product as it is as a flocculant derived from persimmon to be applied to the present invention (for example, those sold under the name of Ginjo Tama Shibu aseptic from Tomiyama Co., Ltd.), It can also be prepared if necessary. The production of the astringent flocculant generally comprises a step of squeezing the persimmon astringent manually or using a machine, and a subsequent aging step. The use concentration of the persimmon flocculant, the ratio of addition to the leachate, and the like can be easily determined by experiments depending on the persimmon agglutinating agent to be applied. For example, the astringent flocculant manufactured by Tomiyama Co., Ltd. is generally used as a 10% aqueous solution (see Examples described later).
かくして、本発明に従えば、凝集剤、とりわけ、柿渋より製造された凝集剤を用いることにより、従来からの重金属の分離・回収方法、すなわち、(1)イオン交換、吸着法あるいは沈殿法、および(2)電解採取法における既述の問題点を解消して、重金属およびウロの有効利用を図ることができる。以下、それらの既存の方法と組み合わせると好適な本発明の実施の態様に沿って本発明を詳述する。 Thus, according to the present invention, by using a flocculant, especially a flocculant produced from astringent shiitake, a conventional heavy metal separation and recovery method, namely (1) ion exchange, adsorption method or precipitation method, and (2) The above-described problems in the electrolytic collection method can be solved, and heavy metals and uro can be effectively used. Hereinafter, the present invention will be described in detail according to the preferred embodiments of the present invention when combined with these existing methods.
(I)イオン交換、吸着法あるいは沈殿法による重金属の除去
先に述べたように重金属の浸出には可及的に低いpHの液が好ましい。一方、重金属のイオン交換、吸着あるいは沈殿による除去にはpHを高くする必要がある。pHを高めるためには、通常は苛性ソーダ等のアルカリ物質の添加が必要である。しかしこれはコストの上昇を伴う。本発明に従えば、浸出液の初期pHおよびウロと浸出液との固液比を適切な値に保つことにより外部からのアルカリ物質の添加無しに自然分離に適したpHとなる。
(I) Removal of heavy metals by ion exchange, adsorption method or precipitation method As described above, a liquid having a pH as low as possible is preferable for leaching of heavy metals. On the other hand, it is necessary to increase the pH in order to remove heavy metals by ion exchange, adsorption or precipitation. In order to increase the pH, it is usually necessary to add an alkaline substance such as caustic soda. However, this is accompanied by an increase in cost. According to the present invention, the initial pH of the leachate and the solid-liquid ratio between uro and leachate are maintained at appropriate values, thereby achieving a pH suitable for natural separation without the addition of an alkaline substance from the outside.
図1は、これらのことによりイオン交換、吸着法あるいは沈殿法により重金属を除去するのに適した方法のフローシートの1例を示すものである。
図1にも示されるように、本発明の好ましい態様に従えば、2つの槽を用いて、浸漬工程を実施する。すなわち、第1の槽において、pH1〜2の希硫酸水溶液を用いてウロ中の重金属を浸出させ、さらに、第1槽で得られた浸出液を第2の槽に移し、その第2槽において当該浸出液に第1槽におけるよりも多い量のウロを浸漬して、その浸出液のpHが2.5〜5になるまで浸漬を行う。このように、第1槽は重金属を浸出させるためのものであり、第2槽はpHを上昇させるためのものである。
FIG. 1 shows an example of a flow sheet of a method suitable for removing heavy metals by ion exchange, adsorption method or precipitation method.
As shown in FIG. 1, according to a preferred embodiment of the present invention, the dipping process is performed using two tanks. That is, in the first tank, heavy metal in uro is leached using a dilute sulfuric acid aqueous solution having a pH of 1-2, and further, the leachate obtained in the first tank is transferred to the second tank. A larger amount of uro is immersed in the leachate than in the first tank, and dipping is performed until the pH of the leachate is 2.5-5. Thus, the first tank is for leaching heavy metals, and the second tank is for raising the pH.
ウロからの金属の浸出には低いpHの酸水溶液、すなわちより高濃度の酸水溶液が好ましい。しかし浸出された重金属を後に吸着法などにより分離する場合には、高濃度の酸は障害を与える。このため、吸着などによる重金属の分離に障害を与えず、かつウロから重金属を効果的に浸出させる最適の酸濃度あるいは最適のpHの範囲を見出すことが肝要である。本発明者は、そのpHの範囲は1〜2、好ましくは1.3〜1.9であることを見出している。図1に示す例では、pHが1.5の希硫酸水溶液を用いて重金属の浸出を行っている。 A low pH acid aqueous solution, that is, a higher concentration aqueous acid solution is preferred for metal leaching from uro. However, when the leached heavy metal is later separated by an adsorption method or the like, a high concentration of acid gives an obstacle. For this reason, it is important to find an optimum acid concentration or optimum pH range that does not impede the separation of heavy metals by adsorption or the like and can effectively leach heavy metals from uro. The inventor has found that the pH range is 1-2, preferably 1.3-1.9. In the example shown in FIG. 1, heavy metal is leached using a dilute sulfuric acid aqueous solution having a pH of 1.5.
第1槽における浸出時間は、例えば、30℃で操業する場合は24時間であるが、温度を上げることにより時間を短縮することも可能である。第1槽における固液比は、例えば、1:20〜1:8、好ましくは1:12〜1:9である。このような浸出操作を行うことにより第1槽に入れられたウロの中のカドミウムなどの重金属の濃度は環境基準値以下に低減できる。第1槽での浸出が完了した後は第1槽の浸出液は全て第2槽に移され、その後新たな浸出液が加えられる。この場合の新たな浸出液の硫酸の濃度は、例えば、40〜60mol/m3、このましくは45〜55mol/m3である。また第1槽における浸出中にも、第2槽に関連して後述するように、タンパク質に因りpHの増加が起こるが、第1槽におけるpHの増加はカドミウムなどの重金属の完全なる除去に障害をもたらすので微量の硫酸を添加することによりpHを適正値、例えば、pH1.5に保つことが好ましい。 The leaching time in the first tank is, for example, 24 hours when operating at 30 ° C., but the time can be shortened by raising the temperature. The solid-liquid ratio in the first tank is, for example, 1:20 to 1: 8, preferably 1:12 to 1: 9. By performing such a leaching operation, the concentration of heavy metals such as cadmium in the urine placed in the first tank can be reduced below the environmental standard value. After the leaching in the first tank is completed, all of the leaching liquid in the first tank is transferred to the second tank, and then a new leaching liquid is added. In this case, the concentration of sulfuric acid in the new leachate is, for example, 40 to 60 mol / m 3 , preferably 45 to 55 mol / m 3 . During the leaching in the first tank, as will be described later in connection with the second tank, an increase in pH occurs due to protein, but the increase in pH in the first tank is an obstacle to the complete removal of heavy metals such as cadmium. Therefore, it is preferable to keep the pH at an appropriate value, for example, pH 1.5 by adding a small amount of sulfuric acid.
第1槽における浸出が完了した後は、第1槽で得られた浸出液は全て第2層に移される。すなわち、第1槽と第2槽の液量は同じである。第2槽においては、如上の第1槽で得られた浸出液に、第1槽におけるよりも多い量のウロを浸漬する。図1では第1槽の2倍量のウロを第2槽において浸漬している例を示している。かくして、第2槽における固液比は、例えば、1:10〜1:3、好ましくは1:6〜1:4となる。浸漬時間は、一般に、5〜6時間である。 After the leaching in the first tank is completed, all the leachate obtained in the first tank is transferred to the second layer. That is, the liquid volume of the 1st tank and the 2nd tank is the same. In the second tank, a larger amount of uro is immersed in the leachate obtained in the first tank as described above than in the first tank. FIG. 1 shows an example in which a double amount of urine in the first tank is immersed in the second tank. Thus, the solid-liquid ratio in the second tank is, for example, 1:10 to 1: 3, preferably 1: 6 to 1: 4. The immersion time is generally 5 to 6 hours.
このような操作が第2槽で行われると、浸出液のpHが次第に上昇する。これは、ウロ中のタンパク質の加水分解反応に因るものと理解される。ここで、後に、凝集剤、特に柿渋の凝集剤を用いてタンパク質や脂肪の凝集・除去を行う場合、液のpHが高すぎると凝集の結果生成されるフロック中に重金属が含まれる。重金属の効果的な分離・除去のためにはタンパク質や脂肪と重金属とを個々別々に分離することが重要であり、フロック中に重金属が含まれることは分離操作が複雑となり、コストの上昇を招く。本発明者らはフロック中に重金属が含まれないためのpHが約5以下、好ましくは約4.5以下であることを見出した。 When such an operation is performed in the second tank, the pH of the leachate gradually increases. This is understood to be due to the hydrolysis reaction of the protein in uro. Here, when the protein or fat is aggregated / removed later using an aggregating agent, particularly an astringent agglutinating agent, if the pH of the liquid is too high, heavy metals are contained in the floc produced as a result of the aggregation. In order to effectively separate and remove heavy metals, it is important to separate proteins, fats and heavy metals separately. The inclusion of heavy metals in the floc complicates the separation operation and leads to an increase in cost. . The present inventors have found that the pH for preventing heavy metals from being contained in the floc is about 5 or less, preferably about 4.5 or less.
かくして、第2槽におけるpHを上昇させるための操作は、その浸出液のpHが、一般的には2.5〜5、好ましくは3〜4.5、特に好ましくは3〜4になるまで浸漬を行う。
如上の本発明の浸漬工程のさらに好ましい態様においては、第2槽で浸漬後のウロの一部を第1槽に移し、且つ、第1槽に移したウロに相当する量の新しいウロを第2槽に補充する。図1に示す場合では、好ましい例として、第2槽で浸漬したウロの半分を第1槽に移し、それに相当する新たなウロを補充している。このようにウロと希硫酸の浸出液を互いに逆方向に移動させることを繰り返すことにより連続操作により浸漬工程を実施することができる。
以上のようにして、第1槽から得られカドミウム等の重金属を除去したウロは、肥料や飼料としての利用に供される。
Thus, the operation for increasing the pH in the second tank is carried out until the pH of the leachate is generally 2.5 to 5, preferably 3 to 4.5, particularly preferably 3 to 4. Do.
In a more preferred embodiment of the immersion process of the present invention as described above, a part of the uro after immersion in the second tank is transferred to the first tank, and new uro of an amount corresponding to the uro transferred to the first tank is added to the first tank. Refill 2 tanks. In the case shown in FIG. 1, as a preferred example, half of the urine immersed in the second tank is transferred to the first tub and replenished with new uro corresponding thereto. Thus, the immersion process can be carried out by continuous operation by repeatedly moving the leaching solution of uro and dilute sulfuric acid in opposite directions.
As described above, the urine obtained by removing heavy metals such as cadmium obtained from the first tank is used for fertilizer and feed.
他方、第2槽からの浸出液に柿渋から成る凝集剤を加えると液中の溶解しているタンパク質や脂肪の大部分はフロックとなり、ろ過により容易に除去できる。この場合に添加される柿渋凝集剤の濃度および量は、例えば、10%水溶液として、浸出液1m3に対して50〜20L、好ましくは35〜30Lである。ろ過して除去したフロック中には重金属は含まれておらず、全て天然の柿渋、タンパク質、脂肪であるので肥料や飼料として利用可能である。
フロックをろ過・分離した後のろ液中の重金属は従来の沈殿法やイオン交換・吸着法により容易に除去することが可能である(図1参照)。
On the other hand, when a flocculant composed of persimmon is added to the leachate from the second tank, most of the dissolved protein and fat in the liquid become floc and can be easily removed by filtration. The concentration and amount of the astringent flocculant added in this case are, for example, 50 to 20 L, preferably 35 to 30 L with respect to 1 m 3 of the leachate as a 10% aqueous solution. The floc removed by filtration does not contain heavy metals and can be used as fertilizer or feed because it is all natural astringent, protein and fat.
The heavy metal in the filtrate after filtering and separating the floc can be easily removed by a conventional precipitation method or ion exchange / adsorption method (see FIG. 1).
(II)電解採取による重金属の除去
既述のように、現在行われている電解採取においては3%の希硫酸水溶液(pH=0.7)が浸漬液として使用されている。本発明に従えば、このようなpHのきわめて低い液に対しても柿渋から成る凝集剤を加えると液中に溶解しているタンパク質や脂肪の大部分はフロックとなり、ろ過により容易に除去できる。この場合も添加される柿渋凝集剤の濃度および量は、例えば、10%水溶液として、浸出液1m3に対して50〜20L、好ましくは35〜30Lである。ろ過して除去したフロック中には重金属は含まれておらず、全て天然の柿渋、タンパク質、脂肪であるので肥料や飼料として利用可能である。他方、凝集およびろ過処理後の浸出液は、タンパク質や脂質を含有していないので、カドミウムなどの重金属を除去するための効率的な電解採取を可能にする。
以下に、実施例により本発明の実施の形態を更に詳細に説明するが、本発明はこれらの実施例に制限されるものではない。
(II) Removal of heavy metals by electrowinning As described above, 3% dilute sulfuric acid aqueous solution (pH = 0.7) is used as the immersion liquid in the current electrowinning. According to the present invention, when a flocculant composed of persimmon is added to such a liquid having a very low pH, most of the protein and fat dissolved in the liquid become floc and can be easily removed by filtration. Also in this case, the concentration and amount of the astringent flocculant added is, for example, 50 to 20 L, preferably 35 to 30 L as a 10% aqueous solution with respect to 1 m 3 of the leachate. The floc removed by filtration does not contain heavy metals and can be used as fertilizer or feed because it is all natural astringent, protein and fat. On the other hand, the leachate after aggregation and filtration treatment does not contain proteins or lipids, thus enabling efficient electrowinning to remove heavy metals such as cadmium.
Hereinafter, the embodiments of the present invention will be described in more detail by way of examples, but the present invention is not limited to these examples.
ウロの浸出液のpHの時間変化
この実施例は、ウロの希硫酸浸出液のpHがウロにより上昇する事実を示すものである。図2に100gのウロの試料を初期pHが1.6および1.9の希硫酸浸出液1Lに浸漬した場合の液のpHと時間との関係を示す。pHは時間とともに増加していることが分かる。初期pHが1.9の場合に15時間の後、pHが急激に増加しているのは、この時点で50gのウロの試料を新たに加えたためである。
Change in pH of uro leachate over time This example illustrates the fact that the pH of uro dilute sulfuric acid leachate is increased by uro. FIG. 2 shows the relationship between pH and time of a 100 g urine sample immersed in 1 L of dilute sulfuric acid leachate having an initial pH of 1.6 and 1.9. It can be seen that the pH increases with time. The reason why the pH rapidly increased after 15 hours when the initial pH was 1.9 was that a 50 g sample of uro was newly added at this point.
ウロからカドミウムの全量を浸出・除去するのに必要な時間
この実施例は、硫酸水溶液を用いてウロからカドミウムを浸出・除去するための所要時間を例示するものである。図3に30℃においてpH=1.5の希硫酸浸出液を用いた場合のウロ(100g:約30個の試料)からのカドミウムの浸出・除去%と浸漬時間との関係を示す。100%の浸出・除去を達成するには24時間以上の浸漬時間が必要なことがわかる。
Time required for leaching and removing the entire amount of cadmium from uro This example illustrates the time required for leaching and removing cadmium from uro using an aqueous sulfuric acid solution. FIG. 3 shows the relationship between the leaching / removal percentage of cadmium from uro (100 g: about 30 samples) and the soaking time when a dilute sulfuric acid leaching solution having a pH = 1.5 at 30 ° C. is used. It can be seen that an immersion time of 24 hours or more is required to achieve 100% leaching / removal.
図1に示すプロセスによるウロの処理
この実施例は、そのフローシートを図1に示すプロセスによりウロを処理した場合の1例を示す。100gのウロを平板上の笊の上に置き、50mM(M=mol/L)の濃度の希硫酸水溶液(pH=1.5)1Lの入ったビーカー(1番目のビーカー:第1槽)中にいれ、マグネチックスターラーで水溶液を攪拌した。この場合水溶液を加熱することにより液の温度を30℃に保った。24時間後、ウロを取り出し、浸出液は2番目のビーカー(第2槽)に移した。取り出したウロを王水で全溶解し、液中のカドミウムの濃度を島津製ICPS−8100型ICP原子発光分光分析装置を用いて測定したところ全く含まれてないことを確認した。2番目のビーカー中に1番目のビーカーと同様な方法で200gのウロを入れ、同様な方法で攪拌した。5時間後の液のpHは4.0であり、カドミウムの濃度は3.16ppmであった。
ウロを取り出した後、浸出後液に水で10%に希釈した(株)トミヤマ製の柿渋凝集剤、吟醸玉渋無菌を33mL添加して攪拌した。生成したフロックをろ過して取り除き、ろ液中のカドミウムの濃度を同様な方法で分析したところ3.05ppmであった。凝集操作の前後でカドミウムの濃度が3.16から3.05ppmに減少したのは33mLの柿渋液の添加による希釈のためである。したがって浸出されたカドミウムはフロックには行かず全量がろ液に移行したと認められる。
ろ液に少量の水酸化カルシウムを添加することにより、カドミウムを始めとする全ての金属分を水酸化物の沈殿とし、これをろ過して分離した。ろ液中にはカドミウムは検出されなかった。
以上のようにそのフローシートを図1に示すプロセスに従ってウロを処理した場合、ウロ中のカドミウムは全て除去され、除去されたカドミウムは水酸化物の沈殿として安価なコストで回収できることが明らかとなった。
1. Processing of scale by the process shown in FIG. 1 This embodiment shows an example in which the scale is processed by the process shown in FIG. In a beaker (first beaker: first tank) containing 1 liter of dilute sulfuric acid aqueous solution (pH = 1.5) having a concentration of 50 mM (M = mol / L) with 100 g of urine placed on a plate. The aqueous solution was stirred with a magnetic stirrer. In this case, the temperature of the liquid was kept at 30 ° C. by heating the aqueous solution. After 24 hours, the scale was taken out and the leachate was transferred to the second beaker (second tank). The extracted uro was completely dissolved in aqua regia, and the concentration of cadmium in the liquid was measured using an ICPS-8100 type ICP atomic emission spectrometer manufactured by Shimadzu. In the second beaker, 200 g of uro was put in the same manner as the first beaker and stirred in the same manner. The pH of the solution after 5 hours was 4.0, and the concentration of cadmium was 3.16 ppm.
After the uro was taken out, 33 mL of Tomiyama Co., Ltd. Toshiyama Co., Ltd. Ginjo Tama Shibu Aseptic, diluted to 10% with water was added to the solution after leaching and stirred. The produced floc was removed by filtration, and the concentration of cadmium in the filtrate was analyzed by the same method and found to be 3.05 ppm. The cadmium concentration decreased from 3.16 to 3.05 ppm before and after the agglomeration operation because of the addition of 33 mL of persimmon juice. Therefore, the leached cadmium does not go to floc, and it is recognized that the entire amount has been transferred to the filtrate.
By adding a small amount of calcium hydroxide to the filtrate, all metal components including cadmium were precipitated as hydroxides, which were separated by filtration. Cadmium was not detected in the filtrate.
As described above, when the flow sheet is processed according to the process shown in FIG. 1, all of the cadmium in the uro is removed and the removed cadmium can be recovered at a low cost as a hydroxide precipitate. It was.
電解採取用希硫酸浸漬液からのタンパク質や脂肪の除去
この実施例は、電解採取によりカドミウム等を除去するために実際に運転されているプラント由来の低pH希硫酸浸漬液からタンパク質や脂肪を除去するのに本発明が適用できることを示すものである。
平成18年2月3日に砂原のウロの処理施設において採取したpHが0.7の実際の希硫酸浸漬液15mL中に10%に希釈した(株)トミヤマ製の柿渋凝集剤、吟醸玉渋無菌を0.5mL添加したところ良好なる凝集・分離が達成された。最初の浸漬液とフロックをろ過して取り除いた後の液中の亜鉛とカドミウムの濃度を島津製ICPS−8100型原子吸光発光分析装置により測定した。その結果を表1に示す。両金属の濃度は凝集の前後で殆ど変化しておらず、フロックに移行していないことが分かる。すなわち、カドミウム等の重金属を含有せず肥料や飼料として利用できるフロックが得られるとともに、タンパク質や脂質を含有せず電解採取に適した浸出液が得られることが確認できた。
Removal of protein and fat from dilute sulfuric acid soaking solution for electrowinning This example removes protein and fat from low pH dilute sulfuric acid soaking solution that is actually operated to remove cadmium etc. by electrowinning However, it shows that the present invention can be applied.
Ginjo Tamashibu, an agaric flocculant made by Tomiyama Co., Ltd. diluted to 10% in 15 mL of an actual dilute sulfuric acid immersion solution with a pH of 0.7 collected at a processing facility for Uro in Sunahara on February 3, 2006 When 0.5 mL of sterilization was added, good aggregation / separation was achieved. The concentration of zinc and cadmium in the liquid after removing the first immersion liquid and floc by filtration was measured with an ICPS-8100 type atomic absorption emission spectrometer manufactured by Shimadzu. The results are shown in Table 1. It can be seen that the concentrations of both metals hardly change before and after the aggregation and do not shift to floc. That is, it was confirmed that a floc that can be used as fertilizer or feed without containing heavy metals such as cadmium can be obtained, and that a leachate suitable for electrowinning can be obtained without containing protein or lipid.
平成12年の北海道におけるホタテ貝の漁獲量は約40万トンであり、また、青森県においても平成14年のホタテ貝の漁獲量は9万5千トンであり、ホタテ貝による収益は、これらの地域において産業上の重要な地位を占めている。ホタテ貝の内、市場に出るのは主として貝柱の部分であり、殻や内臓の部分は廃棄物となる。この内、中腸腺の部分にはかなりの高濃度のカドミウム等の重金属が含まれており、難処理有害廃棄物となっている。一方で内臓中には良質のタンパク質や脂肪が豊富に含まれており、重金属を除去することができれば良質の肥料や飼料の原料となる。
本発明はこのようなホタテ貝の内臓廃棄物の資源化と重金属の有効利用に寄与する技術を提供するものであり、北海道や青森県を初めとする地域の産業に大きく貢献するものである。
The catch of scallops in Hokkaido in 2000 was about 400,000 tons. In Aomori Prefecture, the catch of scallops in 2002 was 95,000 tons. Occupies an important industrial position in the region. Of the scallops, the main part of the market is the scallops, and the shells and internal organs become waste. Of these, the midgut gland contains heavy metals such as cadmium at a very high concentration, making it a difficult-to-process hazardous waste. On the other hand, the internal organs are rich in high-quality proteins and fats, and if heavy metals can be removed, they become raw materials for high-quality fertilizers and feeds.
The present invention provides a technology that contributes to the recycling of visceral waste from scallops and the effective use of heavy metals, and greatly contributes to local industries such as Hokkaido and Aomori Prefecture.
Claims (3)
The method according to claim 1 or 2, wherein the heavy metal-containing liquid after the flocculant addition step is subjected to heavy metal separation / recovery by ion exchange, adsorption, or precipitation.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2006054267A JP4734643B2 (en) | 2006-03-01 | 2006-03-01 | Method for removing heavy metals from scallop visceral waste |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2006054267A JP4734643B2 (en) | 2006-03-01 | 2006-03-01 | Method for removing heavy metals from scallop visceral waste |
Publications (2)
Publication Number | Publication Date |
---|---|
JP2007229618A JP2007229618A (en) | 2007-09-13 |
JP4734643B2 true JP4734643B2 (en) | 2011-07-27 |
Family
ID=38550745
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP2006054267A Active JP4734643B2 (en) | 2006-03-01 | 2006-03-01 | Method for removing heavy metals from scallop visceral waste |
Country Status (1)
Country | Link |
---|---|
JP (1) | JP4734643B2 (en) |
Families Citing this family (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN106238441B (en) * | 2016-08-31 | 2018-09-04 | 北京铮实环保工程有限公司 | Remove the technique and its electrolysis unit of heavy metal in house refuse organic waste |
CN106566930A (en) * | 2016-11-02 | 2017-04-19 | 深圳清华大学研究院 | Process for recovering cadmium from cadmium-contained incineration slag |
Citations (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH09299922A (en) * | 1996-05-18 | 1997-11-25 | Tomoji Tanaka | Effective treatment of viscera of scallops |
JPH1052692A (en) * | 1996-08-09 | 1998-02-24 | Yukimasa Sato | Method and apparatus for removal of heavy metal and method for separation of protein in removal of heavy metal |
JPH11172344A (en) * | 1997-12-15 | 1999-06-29 | Ishitsuki Shoten:Kk | Method for removing cadmium from internal organs of fish and shellfishes and method for treating internal organs of fish and shellfishes |
JP2000166517A (en) * | 1998-12-11 | 2000-06-20 | Hitachi Plant Eng & Constr Co Ltd | Removal of heavy metal in biopolymer and device |
JP2000296389A (en) * | 1999-02-09 | 2000-10-24 | Shiro Yoshizaki | Method for removing heavy metals |
JP2001054783A (en) * | 1999-08-19 | 2001-02-27 | Takahashi Ko | Method for removing harmful metal from mollusk tissue |
JP2002159952A (en) * | 2000-11-28 | 2002-06-04 | Japan Atom Energy Res Inst | Method for removing harmful metal from waste viscus of scallop |
JP2002336818A (en) * | 2001-05-17 | 2002-11-26 | Tamura Kagaku Kenkyusho:Kk | Method for treating processing residue of mollusk food, treatment process and treatment device used therefor |
JP2004344802A (en) * | 2003-05-23 | 2004-12-09 | Marine Science Kk | Method of obtaining useful substance from tissue of scallop gut, and plant therefor |
JP2005058951A (en) * | 2003-08-19 | 2005-03-10 | Katsutoshi Inoue | Method for separation, removal, condensation and recovery of heavy metal, fat and protein in scallop internal organ immersed liquid |
JP2005087931A (en) * | 2003-09-19 | 2005-04-07 | Hokkaido | Method and device for removing heavy metal from organism |
-
2006
- 2006-03-01 JP JP2006054267A patent/JP4734643B2/en active Active
Patent Citations (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH09299922A (en) * | 1996-05-18 | 1997-11-25 | Tomoji Tanaka | Effective treatment of viscera of scallops |
JPH1052692A (en) * | 1996-08-09 | 1998-02-24 | Yukimasa Sato | Method and apparatus for removal of heavy metal and method for separation of protein in removal of heavy metal |
JPH11172344A (en) * | 1997-12-15 | 1999-06-29 | Ishitsuki Shoten:Kk | Method for removing cadmium from internal organs of fish and shellfishes and method for treating internal organs of fish and shellfishes |
JP2000166517A (en) * | 1998-12-11 | 2000-06-20 | Hitachi Plant Eng & Constr Co Ltd | Removal of heavy metal in biopolymer and device |
JP2000296389A (en) * | 1999-02-09 | 2000-10-24 | Shiro Yoshizaki | Method for removing heavy metals |
JP2001054783A (en) * | 1999-08-19 | 2001-02-27 | Takahashi Ko | Method for removing harmful metal from mollusk tissue |
JP2002159952A (en) * | 2000-11-28 | 2002-06-04 | Japan Atom Energy Res Inst | Method for removing harmful metal from waste viscus of scallop |
JP2002336818A (en) * | 2001-05-17 | 2002-11-26 | Tamura Kagaku Kenkyusho:Kk | Method for treating processing residue of mollusk food, treatment process and treatment device used therefor |
JP2004344802A (en) * | 2003-05-23 | 2004-12-09 | Marine Science Kk | Method of obtaining useful substance from tissue of scallop gut, and plant therefor |
JP2005058951A (en) * | 2003-08-19 | 2005-03-10 | Katsutoshi Inoue | Method for separation, removal, condensation and recovery of heavy metal, fat and protein in scallop internal organ immersed liquid |
JP2005087931A (en) * | 2003-09-19 | 2005-04-07 | Hokkaido | Method and device for removing heavy metal from organism |
Also Published As
Publication number | Publication date |
---|---|
JP2007229618A (en) | 2007-09-13 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
Shrivastava | A review on copper pollution and its removal from water bodies by pollution control technologies | |
Syed | Silver recovery aqueous techniques from diverse sources: Hydrometallurgy in recycling | |
Simate et al. | Acid mine drainage: Challenges and opportunities | |
Kadirvelu et al. | Agricutural by-product as metal adsorbent: sorption of lead (II) from aqueous solution onto coirpith carbon | |
US8888890B2 (en) | Ore leaching method for metals recovery | |
CN104086054A (en) | Method for treating heavy metal wastewater by adopting chemical precipitation-flocculation-phytoremediation process | |
CN102191380A (en) | Recovery method for cobalt | |
Wu et al. | High value-added resource utilization of solid waste: review of prospects for supercritical CO2 extraction of valuable metals | |
JP4734643B2 (en) | Method for removing heavy metals from scallop visceral waste | |
CN109097568B (en) | Method for separating selenium and arsenic from alkaline leaching solution containing selenium and arsenic | |
Hakeem et al. | Investigations into the closed-loop hydrometallurgical process for heavy metals removal and recovery from biosolids via mild acid pre-treatment | |
US4317804A (en) | Process for the selective removal of ferric ion from an aqueous solution containing ferric and other metal ions | |
Sun et al. | Research progress of arsenic removal from wastewater | |
Kalderis et al. | Characterization and treatment of wastewater produced during the hydro-metallurgical extraction of germanium from fly ash | |
CN104030510A (en) | Method for recycling acid and heavy metal in gold smelting acid wastewater | |
JPS60106585A (en) | Treatment of waste water | |
CN111957734B (en) | Method for in-situ remediation of soil heavy metal pollution | |
CA3212288A1 (en) | Removal of arsenic, antimony and toxic metals from contaminated substrate | |
JPS6219496B2 (en) | ||
CN108996767B (en) | Method for removing metal ions by hydration-adsorption | |
JP2005058951A (en) | Method for separation, removal, condensation and recovery of heavy metal, fat and protein in scallop internal organ immersed liquid | |
Mirea et al. | The removal of heavy metals using the bulk liquid membrane technique | |
KR20150112576A (en) | Effective and eco-friendly Washing Method for metal-contaminated Soil Using Ferric | |
Ukiwe et al. | Progressive acidification: an aspect of chemical leaching of sewage sludge | |
JP5142490B2 (en) | Water treatment method |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
A621 | Written request for application examination |
Free format text: JAPANESE INTERMEDIATE CODE: A621 Effective date: 20090116 |
|
A977 | Report on retrieval |
Free format text: JAPANESE INTERMEDIATE CODE: A971007 Effective date: 20101012 |
|
A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20101130 |
|
A521 | Request for written amendment filed |
Free format text: JAPANESE INTERMEDIATE CODE: A821 Effective date: 20101216 Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20101216 |
|
A521 | Request for written amendment filed |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20110105 |
|
A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20110125 |
|
A521 | Request for written amendment filed |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20110304 Free format text: JAPANESE INTERMEDIATE CODE: A821 Effective date: 20110304 |
|
A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 20110405 |
|
R150 | Certificate of patent or registration of utility model |
Free format text: JAPANESE INTERMEDIATE CODE: R150 |