JP3994957B2 - Method and apparatus for recycling foundry sand and water-soluble inorganic salt binder - Google Patents
Method and apparatus for recycling foundry sand and water-soluble inorganic salt binder Download PDFInfo
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- 239000004576 sand Substances 0.000 title claims description 134
- 239000011230 binding agent Substances 0.000 title claims description 101
- 229910017053 inorganic salt Inorganic materials 0.000 title claims description 78
- 238000000034 method Methods 0.000 title claims description 30
- 238000004064 recycling Methods 0.000 title claims description 6
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 52
- 239000002002 slurry Substances 0.000 claims description 26
- 238000005266 casting Methods 0.000 claims description 24
- 239000007864 aqueous solution Substances 0.000 claims description 21
- 239000000243 solution Substances 0.000 claims description 18
- 239000006228 supernatant Substances 0.000 claims description 15
- 239000000047 product Substances 0.000 claims description 11
- 238000000465 moulding Methods 0.000 claims description 9
- 208000005156 Dehydration Diseases 0.000 claims description 8
- 230000018044 dehydration Effects 0.000 claims description 8
- 238000006297 dehydration reaction Methods 0.000 claims description 8
- 239000000203 mixture Substances 0.000 claims description 8
- 239000002245 particle Substances 0.000 claims description 8
- 239000007788 liquid Substances 0.000 claims description 7
- 229910000838 Al alloy Inorganic materials 0.000 claims description 6
- 238000004898 kneading Methods 0.000 claims description 6
- 238000001556 precipitation Methods 0.000 claims description 5
- 229920006395 saturated elastomer Polymers 0.000 claims description 4
- 238000005406 washing Methods 0.000 claims description 2
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 104
- CSNNHWWHGAXBCP-UHFFFAOYSA-L Magnesium sulfate Chemical compound [Mg+2].[O-][S+2]([O-])([O-])[O-] CSNNHWWHGAXBCP-UHFFFAOYSA-L 0.000 description 12
- 239000000428 dust Substances 0.000 description 11
- 229910052943 magnesium sulfate Inorganic materials 0.000 description 6
- 235000019341 magnesium sulphate Nutrition 0.000 description 6
- 239000000463 material Substances 0.000 description 6
- 239000000843 powder Substances 0.000 description 6
- 238000011069 regeneration method Methods 0.000 description 6
- 239000011347 resin Substances 0.000 description 5
- 229920005989 resin Polymers 0.000 description 5
- 238000005498 polishing Methods 0.000 description 4
- 239000011734 sodium Substances 0.000 description 4
- 238000010586 diagram Methods 0.000 description 3
- 238000005265 energy consumption Methods 0.000 description 3
- 239000011256 inorganic filler Substances 0.000 description 3
- 229910003475 inorganic filler Inorganic materials 0.000 description 3
- 238000005495 investment casting Methods 0.000 description 3
- 230000001172 regenerating effect Effects 0.000 description 3
- 239000000377 silicon dioxide Substances 0.000 description 3
- 239000003232 water-soluble binding agent Substances 0.000 description 3
- UQSXHKLRYXJYBZ-UHFFFAOYSA-N Iron oxide Chemical compound [Fe]=O UQSXHKLRYXJYBZ-UHFFFAOYSA-N 0.000 description 2
- CDBYLPFSWZWCQE-UHFFFAOYSA-L Sodium Carbonate Chemical compound [Na+].[Na+].[O-]C([O-])=O CDBYLPFSWZWCQE-UHFFFAOYSA-L 0.000 description 2
- FAPWRFPIFSIZLT-UHFFFAOYSA-M Sodium chloride Chemical compound [Na+].[Cl-] FAPWRFPIFSIZLT-UHFFFAOYSA-M 0.000 description 2
- XLOMVQKBTHCTTD-UHFFFAOYSA-N Zinc monoxide Chemical compound [Zn]=O XLOMVQKBTHCTTD-UHFFFAOYSA-N 0.000 description 2
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 2
- OSGAYBCDTDRGGQ-UHFFFAOYSA-L calcium sulfate Chemical compound [Ca+2].[O-]S([O-])(=O)=O OSGAYBCDTDRGGQ-UHFFFAOYSA-L 0.000 description 2
- 239000013058 crude material Substances 0.000 description 2
- NJLLQSBAHIKGKF-UHFFFAOYSA-N dipotassium dioxido(oxo)titanium Chemical compound [K+].[K+].[O-][Ti]([O-])=O NJLLQSBAHIKGKF-UHFFFAOYSA-N 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 238000005259 measurement Methods 0.000 description 2
- 150000003839 salts Chemical class 0.000 description 2
- 238000004062 sedimentation Methods 0.000 description 2
- HBMJWWWQQXIZIP-UHFFFAOYSA-N silicon carbide Chemical compound [Si+]#[C-] HBMJWWWQQXIZIP-UHFFFAOYSA-N 0.000 description 2
- 229910010271 silicon carbide Inorganic materials 0.000 description 2
- 239000007921 spray Substances 0.000 description 2
- 229910052845 zircon Inorganic materials 0.000 description 2
- GFQYVLUOOAAOGM-UHFFFAOYSA-N zirconium(iv) silicate Chemical compound [Zr+4].[O-][Si]([O-])([O-])[O-] GFQYVLUOOAAOGM-UHFFFAOYSA-N 0.000 description 2
- 239000005995 Aluminium silicate Substances 0.000 description 1
- BHPQYMZQTOCNFJ-UHFFFAOYSA-N Calcium cation Chemical compound [Ca+2] BHPQYMZQTOCNFJ-UHFFFAOYSA-N 0.000 description 1
- JLVVSXFLKOJNIY-UHFFFAOYSA-N Magnesium ion Chemical compound [Mg+2] JLVVSXFLKOJNIY-UHFFFAOYSA-N 0.000 description 1
- BPQQTUXANYXVAA-UHFFFAOYSA-N Orthosilicate Chemical compound [O-][Si]([O-])([O-])[O-] BPQQTUXANYXVAA-UHFFFAOYSA-N 0.000 description 1
- PMZURENOXWZQFD-UHFFFAOYSA-L Sodium Sulfate Chemical compound [Na+].[Na+].[O-]S([O-])(=O)=O PMZURENOXWZQFD-UHFFFAOYSA-L 0.000 description 1
- FKNQFGJONOIPTF-UHFFFAOYSA-N Sodium cation Chemical compound [Na+] FKNQFGJONOIPTF-UHFFFAOYSA-N 0.000 description 1
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N Titan oxide Chemical compound O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
- 239000000853 adhesive Substances 0.000 description 1
- 230000001070 adhesive effect Effects 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- 235000012211 aluminium silicate Nutrition 0.000 description 1
- 150000001450 anions Chemical class 0.000 description 1
- 229910021538 borax Inorganic materials 0.000 description 1
- 239000011575 calcium Substances 0.000 description 1
- 229910001424 calcium ion Inorganic materials 0.000 description 1
- 150000001768 cations Chemical class 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 239000002826 coolant Substances 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 230000018109 developmental process Effects 0.000 description 1
- KZHJGOXRZJKJNY-UHFFFAOYSA-N dioxosilane;oxo(oxoalumanyloxy)alumane Chemical compound O=[Si]=O.O=[Si]=O.O=[Al]O[Al]=O.O=[Al]O[Al]=O.O=[Al]O[Al]=O KZHJGOXRZJKJNY-UHFFFAOYSA-N 0.000 description 1
- 238000010410 dusting Methods 0.000 description 1
- 230000005611 electricity Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000001704 evaporation Methods 0.000 description 1
- 230000008020 evaporation Effects 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 238000002347 injection Methods 0.000 description 1
- 239000007924 injection Substances 0.000 description 1
- 238000011835 investigation Methods 0.000 description 1
- 230000001678 irradiating effect Effects 0.000 description 1
- 230000002427 irreversible effect Effects 0.000 description 1
- NLYAJNPCOHFWQQ-UHFFFAOYSA-N kaolin Chemical compound O.O.O=[Al]O[Si](=O)O[Si](=O)O[Al]=O NLYAJNPCOHFWQQ-UHFFFAOYSA-N 0.000 description 1
- INHCSSUBVCNVSK-UHFFFAOYSA-L lithium sulfate Inorganic materials [Li+].[Li+].[O-]S([O-])(=O)=O INHCSSUBVCNVSK-UHFFFAOYSA-L 0.000 description 1
- 239000011777 magnesium Substances 0.000 description 1
- 229910001425 magnesium ion Inorganic materials 0.000 description 1
- 239000000395 magnesium oxide Substances 0.000 description 1
- CPLXHLVBOLITMK-UHFFFAOYSA-N magnesium oxide Inorganic materials [Mg]=O CPLXHLVBOLITMK-UHFFFAOYSA-N 0.000 description 1
- AXZKOIWUVFPNLO-UHFFFAOYSA-N magnesium;oxygen(2-) Chemical compound [O-2].[Mg+2] AXZKOIWUVFPNLO-UHFFFAOYSA-N 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 229910003465 moissanite Inorganic materials 0.000 description 1
- 229910052863 mullite Inorganic materials 0.000 description 1
- 230000007935 neutral effect Effects 0.000 description 1
- 230000003472 neutralizing effect Effects 0.000 description 1
- 235000019353 potassium silicate Nutrition 0.000 description 1
- 238000010298 pulverizing process Methods 0.000 description 1
- 230000008929 regeneration Effects 0.000 description 1
- 238000004904 shortening Methods 0.000 description 1
- 229910000029 sodium carbonate Inorganic materials 0.000 description 1
- 239000011780 sodium chloride Substances 0.000 description 1
- 229910001415 sodium ion Inorganic materials 0.000 description 1
- NTHWMYGWWRZVTN-UHFFFAOYSA-N sodium silicate Chemical compound [Na+].[Na+].[O-][Si]([O-])=O NTHWMYGWWRZVTN-UHFFFAOYSA-N 0.000 description 1
- 229910052938 sodium sulfate Inorganic materials 0.000 description 1
- 235000011152 sodium sulphate Nutrition 0.000 description 1
- 235000010339 sodium tetraborate Nutrition 0.000 description 1
- 239000000454 talc Substances 0.000 description 1
- 229910052623 talc Inorganic materials 0.000 description 1
- RBTVSNLYYIMMKS-UHFFFAOYSA-N tert-butyl 3-aminoazetidine-1-carboxylate;hydrochloride Chemical compound Cl.CC(C)(C)OC(=O)N1CC(N)C1 RBTVSNLYYIMMKS-UHFFFAOYSA-N 0.000 description 1
- 238000009210 therapy by ultrasound Methods 0.000 description 1
- 229920001187 thermosetting polymer Polymers 0.000 description 1
- OGIDPMRJRNCKJF-UHFFFAOYSA-N titanium oxide Inorganic materials [Ti]=O OGIDPMRJRNCKJF-UHFFFAOYSA-N 0.000 description 1
- BSVBQGMMJUBVOD-UHFFFAOYSA-N trisodium borate Chemical compound [Na+].[Na+].[Na+].[O-]B([O-])[O-] BSVBQGMMJUBVOD-UHFFFAOYSA-N 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
- 239000011787 zinc oxide Substances 0.000 description 1
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Description
本発明は、水溶性中子から鋳物砂及び水溶性無機塩バインダーを再利用する方法、及びそれに用いる装置に関する。 The present invention relates to a method for reusing casting sand and a water-soluble inorganic salt binder from a water-soluble core, and an apparatus used therefor.
鋳型に溶湯を圧入し，急冷凝固させて鋳物を製造する精密鋳造技術においては、機械部品等の精密鋳造品の内部に空間を設けるために、中子が広く利用されている。例えば、アルミ合金を使ったシリンダの内部空間、エグゾースト内部の冷却媒体通路の作製に中子は不可欠なものである。 In precision casting technology in which a molten metal is press-fitted into a mold and rapidly solidified to produce a casting, a core is widely used to provide a space inside a precision casting such as a machine part. For example, the core is indispensable for the production of the internal space of the cylinder using aluminum alloy and the cooling medium passage inside the exhaust.
中子の強度を増加させるためには、樹脂等のバインダーが使用されている。例えば、鋳物砂・特に中子砂に使われるバインダーには熱硬化樹脂を用いたシェルモールド法、ガス硬化性樹脂を用いたコールドボックス法等が主流であるがこの砂再生法は焙焼又は機械力による研磨等で行っており、多くのエネルギー消費と大量の微紛が発生している。具体的には、焙焼再生法では、７００℃以上に加熱して樹脂分を完全に燃焼させるため、焙焼時のエネルギー多消費、粉塵発生が避けられなかった。 In order to increase the strength of the core, a binder such as a resin is used. For example, the shell mold method using thermosetting resin and the cold box method using gas curable resin are the mainstream for binders used for foundry sand, especially core sand. A lot of energy consumption and a lot of fine powder are generated. Specifically, in the roasting regeneration method, the resin component is completely burned by heating to 700 ° C. or higher, so that energy consumption during dusting and generation of dust are inevitable.
又、無機バインダーには水ガラス等が従来より用いられているが、その砂再生は粉砕、研磨等で多くの動力と発塵を伴ない、鋳造工場の避けられない問題とされていた。即ち、乾式再生法（摩擦・研磨法）では、鋳物砂表面付着の樹脂分等を機械的力で除去するため、砂の摩耗が多く、また粉塵ダストの廃棄物を多量に発生している。エネルギー的には焙焼より有利であるが電力使用量は多い。更に、除去された残留バインダーは再使用できない。このように、無機バインダーを用いた場合の乾式再生法は、エネルギー多消費、粉塵、臭気、廃棄物等の問題を有するものであった。 In addition, water glass or the like has been conventionally used as an inorganic binder, but sand regeneration has been accompanied by a large amount of power and dust generation due to pulverization and polishing, which has been an unavoidable problem in foundries. That is, in the dry regeneration method (friction / polishing method), the resin component and the like adhering to the surface of the foundry sand is removed by mechanical force, so that sand wear is large and a large amount of dust dust is generated. In terms of energy, it is more advantageous than roasting, but uses a lot of electricity. Furthermore, the removed residual binder cannot be reused. Thus, the dry regeneration method using an inorganic binder has problems such as high energy consumption, dust, odor, and waste.
しかも、焙焼再生法、乾式再生法（摩擦・研磨法）の両方法とも、鋳物砂の一部を再利用するだけであり、そのプロセスの特徴とあいまって、鋳造後砂に付着しているバインダーの性質は元に戻らないので、破棄するしかなく、そのために多量のエネルギーと粉塵・臭気を発生させている。 In addition, both the roasting regeneration method and the dry regeneration method (friction / polishing method) only recycle part of the foundry sand and, due to the characteristics of the process, adhere to the sand after casting. The nature of the binder is irreversible, so it must be discarded, which generates a lot of energy, dust and odor.
また、下記特許文献１には、有機バインダーを含む砂を特定範囲のＰＨ値となるように塩基または酸で中和して再生し、これを鋳物砂として再利用する技術が開示されている。しかし、この方法も、鋳造後砂に付着しているバインダーの性質は元に戻らないので、破棄するしかなく、そのために多量のエネルギーと粉塵・臭気を発生させている。 Patent Document 1 below discloses a technique for regenerating sand containing an organic binder by neutralizing it with a base or acid so as to have a PH value in a specific range and reusing it as foundry sand. However, in this method, since the property of the binder adhering to the sand after casting cannot be restored, it must be discarded. Therefore, a large amount of energy and dust / odor are generated.
一方、中子バインダーとして無機塩を用いることにより、鋳造時のガス発生量を低減させ、鋳造後は中子砂落しを水で行うことのできる水溶性中子が考えられている。しかしながら、非水溶性中子と同様に水溶性中子では、大量に発生する鋳物砂と無機バインダーの処理を如何にするかという問題があった。 On the other hand, by using an inorganic salt as a core binder, a water-soluble core that can reduce the amount of gas generated at the time of casting and can perform core sand removal with water after casting is considered. However, the water-soluble core, like the water-insoluble core, has a problem of how to treat a large amount of foundry sand and inorganic binder.
一方、水溶性中子バインダーとしては、硫酸マグネシウム（ＭｇＳＯ４）が知られている。しかながら、硫酸マグネシウム（ＭｇＳＯ４）水溶液は、以下の欠点を有している。１）粘着力が弱く、中子強度が充分ではない。２）バインダー必要量が多くなり（水の量も増加する）、鋳物砂の流動性が悪化し、中子造型時にブロー充填性が不十分である。 On the other hand, magnesium sulfate (MgSO 4 ) is known as a water-soluble core binder. However, the magnesium sulfate (MgSO 4 ) aqueous solution has the following drawbacks. 1) Adhesive strength is weak and core strength is not sufficient. 2) The required amount of binder increases (the amount of water also increases), the fluidity of the foundry sand deteriorates, and the blow filling property is insufficient during core molding.
そこで、下記特許文献２には、塩化ナトリウムを基材とし、これに硫酸リチウム２〜４０％、硫酸マグネシウム２〜２０％等を加えた水溶性中子バインダーが開示されている。又、下記特許文献３には、硫酸カルシウムと硫酸マグネシウムから成る水溶性中子バインダーが開示されている。しかしながら、これら特許文献２及び３に開示された水溶性中子バインダーを用いても強度は十分ではなかった。
Therefore,
上記問題に鑑み、本発明は、砂落しが容易な水溶性無機バインダーの開発に基づいて、使用後の鋳物砂及び無機バインダーの両者をほぼ完全に再生・リサイクルする方法及び装置を提供し、水溶性中子を更に実用性のあるものとするとともに、環境性に優れたものとすることを目的とする。 In view of the above problems, the present invention provides a method and apparatus for almost completely regenerating and recycling both the foundry sand and the inorganic binder after use, based on the development of a water-soluble inorganic binder that is easy to remove sand. The purpose of this invention is to make the neutral core more practical and environmentally friendly.
本発明者らは、多数の化合物について検討した結果、特定の水溶性無機塩が水溶性バインダーとして優れていることの知見を得た。かかる知見に基づき、更に検討を進めた結果、鋳物砂を除去する工程から回収・脱水された鋳物砂のスラリーを再混練する工程に至る鋳物砂及び水溶性無機塩バインダーの再利用方法とそれに適用される再利用装置を開発した。 As a result of studying a large number of compounds, the present inventors have obtained knowledge that a specific water-soluble inorganic salt is excellent as a water-soluble binder. As a result of further investigation based on this knowledge, a method for reusing foundry sand and water-soluble inorganic salt binders ranging from the step of removing the foundry sand to the step of re-kneading the recovered and dewatered foundry slurry and its application. Developed reusable equipment.
即ち、第１に、本発明は、鋳物砂及び水溶性無機塩バインダーの再利用方法の発明であり、以下の工程を含む。１）鋳物砂粒子の表面が水溶性無機塩バインダーで被覆された水溶性中子を用いた鋳造品から後記水溶性無機塩バインダー及び水からなる上澄み液の水圧を用いて該鋳物砂を除去する工程、２）該除去された鋳物砂、水溶性無機塩バインダー及び水からなる混合物を貯蔵して、水溶性無機塩バインダー及び水からなる上澄み液と、主として鋳物砂からなり少量の水溶性無機塩バインダー及び水からなるスラリーに分離する沈殿工程、３）該スラリーの水分を所定濃度まで脱水する工程、４）該所定濃度まで脱水されたスラリーを再利用する工程。 That is, first, the present invention is an invention of a method for reusing foundry sand and water-soluble inorganic salt binder, and includes the following steps. 1) The casting sand is removed from a casting using a water-soluble core whose surface is coated with a water-soluble inorganic salt binder using the water pressure of a supernatant liquid composed of the water-soluble inorganic salt binder and water described later. Step 2) A mixture of the removed foundry sand, a water-soluble inorganic salt binder and water is stored, and a supernatant composed of a water-soluble inorganic salt binder and water, and a small amount of water-soluble inorganic salt mainly composed of foundry sand. A precipitation step of separating into a slurry comprising a binder and water, 3) a step of dehydrating the water of the slurry to a predetermined concentration, and 4) a step of reusing the slurry dehydrated to the predetermined concentration.
ここで、前記１）水圧を用いて該鋳物砂を除去する工程において、所定濃度の水溶性無機塩バインダー水溶液を用いることが好ましい。この所定濃度の水溶性無機塩バインダー水溶液は、２）沈殿工程で得られる上澄み液を循環利用するのが好ましい。 Here, in the step 1) of removing the foundry sand using water pressure, it is preferable to use a water-soluble inorganic salt binder aqueous solution having a predetermined concentration. It is preferable to circulate and use the supernatant obtained in the 2) precipitation step for the aqueous solution of the water-soluble inorganic salt binder having a predetermined concentration.
又、前記１）鋳物砂除去工程で用いる所定濃度の水溶性無機塩バインダー水溶液を飽和濃度又は飽和濃度に近くすることにより、前記３）脱水工程が１回でも、得られたスラリーを造型工程に送ることが可能となる。 Further, by bringing the aqueous solution of a water-soluble inorganic salt binder having a predetermined concentration used in the 1) foundry sand removal step into a saturated concentration or close to the saturated concentration, the obtained slurry can be used in the molding step even if the 3) dehydration step is performed once. It becomes possible to send.
更に、前記４）所定濃度まで脱水されたスラリーを再混練する工程において、所定濃度のバインダーを加えて再混練することが好ましい。 Furthermore, in the step 4) of re-kneading the slurry dehydrated to a predetermined concentration, it is preferable to add a binder of a predetermined concentration and re-knead.
第２に、本発明は、別の鋳物砂及び水溶性無機塩バインダーの再利用方法の発明であり、以下の工程を含む。１）鋳物砂粒子の表面が水溶性無機塩バインダーで被覆された水溶性中子を用いた鋳造品から後記水溶性無機塩バインダー及び水からなる上澄み液の水圧を用いて該鋳物砂を除去する工程、２）該除去された鋳物砂、水溶性無機塩バインダー及び水からなる混合物を貯蔵して、水溶性無機塩バインダー及び水からなる上澄み液と、主として鋳物砂からなり少量の水溶性無機塩バインダー及び水からなるスラリーに分離する沈殿工程、３）該スラリーの水分を所定濃度まで脱水する１次脱水工程、４）その後、所定濃度の水溶性無機塩バインダー水溶液を多量に添加し、再度スラリーの水分を所定濃度まで脱水する２次脱水工程、５）該所定濃度まで脱水されたスラリーを再利用する工程。 2ndly, this invention is invention of the reuse method of another foundry sand and a water-soluble inorganic salt binder, and includes the following processes. 1) The casting sand is removed from a casting using a water-soluble core whose surface is coated with a water-soluble inorganic salt binder using the water pressure of a supernatant liquid composed of the water-soluble inorganic salt binder and water described later. Step 2) A mixture of the removed foundry sand, a water-soluble inorganic salt binder and water is stored, and a supernatant composed of a water-soluble inorganic salt binder and water, and a small amount of water-soluble inorganic salt mainly composed of foundry sand. Precipitation step for separating into a slurry consisting of a binder and water, 3) a primary dehydration step for dehydrating the water content of the slurry to a predetermined concentration, and 4) adding a large amount of a water-soluble inorganic salt binder aqueous solution at a predetermined concentration, and then slurrying again. A secondary dehydration step of dehydrating the water to a predetermined concentration, and 5) a step of reusing the slurry dehydrated to the predetermined concentration.
上記第１及び第２の発明において、前記脱水工程は遠心分離機を用いるものであることが好ましい。又、前記鋳物砂を除去する工程の後に、前記鋳物砂、水溶性無機塩バインダー及び水からなるスラリーの上澄み液を用いて製造された鋳物を洗浄する工程を含むことが、製造された鋳物の表面を仕上げる上で好ましい。更に、砂落しを効率的に行うためには、砂落し工程で、超音波処理を用いて前記水溶性中子を水に溶解することが好ましい。 In the first and second inventions, the dehydration step preferably uses a centrifuge. In addition, after the step of removing the foundry sand, a step of washing the foundry product using a supernatant liquid of the slurry consisting of the foundry sand, the water-soluble inorganic salt binder and water, It is preferable for finishing the surface. Furthermore, in order to perform sand removal efficiently, it is preferable to dissolve the water-soluble core in water using ultrasonic treatment in the sand removal step.
第３に、本発明は、鋳物砂及び水溶性無機塩バインダーの再利用装置の発明であり、以下の装置・手段を含む。１）砂落装置：鋳物砂粒子の表面が水溶性無機塩バインダーで被覆された水溶性中子を用いた鋳造品から水圧を用いて該鋳物砂を除去する、２）水溶液噴射装置：該砂落装置に後記溶液バッファー槽から循環ポンプを介して水溶性無機塩バインダー水溶液を噴射する、３）砂沈殿槽：該砂落装置の下方に配置され該除去された鋳物砂、水溶性無機塩バインダー及び水からなるスラリーを貯蔵し鋳物砂を沈殿させる、４）溶液バッファー槽：該砂沈殿槽の上部と連通し鋳物砂と分離した水溶性無機塩バインダー水溶液を貯蔵する、５）脱水装置：該砂沈殿槽の下部と連通し鋳物砂と水溶性無機塩バインダー及び水からなるスラリーを所定濃度まで脱水し、混練砂を造型機へ送る。 3rdly, this invention is invention of the reuse equipment of foundry sand and a water-soluble inorganic salt binder, and includes the following apparatuses and means. 1) Sand drop device: removes the foundry sand using water pressure from a cast product using a water-soluble core in which the surface of the foundry sand particles is coated with a water-soluble inorganic salt binder. 2) Aqueous solution spray device: the sand A water-soluble inorganic salt binder aqueous solution is sprayed from a solution buffer tank to a dropping device via a circulation pump. 3) Sand settling tank: The foundry sand disposed below the sand dropping device and the removed water-soluble inorganic salt binder. And 4) solution buffer tank: storing an aqueous solution of the water-soluble inorganic salt binder separated from the foundry sand in communication with the upper part of the sand sedimentation tank. A slurry consisting of foundry sand, a water-soluble inorganic salt binder and water is communicated with the lower part of the sand settling tank to a predetermined concentration, and the kneaded sand is sent to a molding machine.
上記１）〜５）の装置・手段に加えて、好ましくは、前記脱水装置で脱水溶液である水溶性無機塩バインダー水溶液を前記砂沈殿槽へ導く配管、及び／又は前記溶液バッファー槽に補給水を添加する手段を有することが好ましい。
又、前記脱水装置としては遠心分離機が好ましい。
In addition to the devices and means of 1) to 5) above, preferably, a water-soluble inorganic salt binder aqueous solution, which is a dewatered solution by the dehydrating device, is supplied to the sand settling tank and / or to the solution buffer tank. It is preferable to have a means for adding.
The dehydrator is preferably a centrifuge.
第４に、本発明は、アルミ合金鋳造方法の発明であり、中子造型工程、鋳造工程、及び砂落し工程を含むアルミ合金鋳造方法において、中子造型工程で上記第１又は第２の本発明の方法で回収された鋳物砂及び水溶性無機塩バインダーを再利用する。本発明により、例えば、アルミ合金シリンダ等の精密鋳造品を製造することが出来る。 4thly, this invention is invention of the aluminum alloy casting method, Comprising: In the aluminum alloy casting method containing a core molding process, a casting process, and a sand removal process, it is the said 1st or 2nd book in a core molding process. The foundry sand and water-soluble inorganic salt binder recovered by the method of the invention are reused. According to the present invention, for example, a precision casting such as an aluminum alloy cylinder can be manufactured.
本発明により、鋳物砂粒子の表面が無機塩バインダーで被覆された水溶性中子を用いる鋳造時に、使用後の鋳物砂及び無機バインダーの両者をほぼ完全に再生・リサイクルすることが出来る。本発明により、水溶性中子を更に実用性のあるものとするとともに、環境性に優れたものと出来る。 According to the present invention, at the time of casting using a water-soluble core in which the surfaces of foundry sand particles are coated with an inorganic salt binder, both the used foundry sand and the inorganic binder can be almost completely regenerated and recycled. According to the present invention, the water-soluble core can be made more practical and environmentally friendly.
水又はバインダー水溶液を用いて鋳物砂の砂落しをすることにより、製品に加熱・衝撃を加えることなく砂落し出来るので、軽量薄肉鋳物の鋳造が可能となる。又、粉塵の発生も全くないので、集塵機等の公害対策も不用であり、砂の消耗もなく、ダスト処理も必要ない。更に、アルミ品等では鋳造後の高温粗材でも水で砂落し可能なので、粗材冷却も兼用できるので、生産工程が短縮でき、かつ省エネにも寄与できる。 By removing sand from the foundry sand using water or an aqueous binder solution, the sand can be removed without applying heat or impact to the product. Therefore, it is possible to cast a lightweight thin-walled casting. In addition, since no dust is generated, no pollution measures such as a dust collector are required, no sand is consumed, and no dust treatment is required. In addition, in aluminum products and the like, even a high-temperature rough material after casting can be sanded with water, so that it can also be used for cooling the rough material, thereby shortening the production process and contributing to energy saving.
脱水する際、遠心分離機を用い、かつ所定濃度の溶液を用いることにより、混練砂状態の鋳物砂にできるので、従来の砂混練装置が不用である。よって、砂混練に伴う砂計量、バインダーの計量、及び投入装置等が不要となる。又、中子に付着したバインダーも水に溶けた後、再度鋳物砂の表面に均等に付着させることができるので、バインダーの再利用が極めて容易で１００％近い効率のリサイクルができる。更に、主たる再生装置は遠心分離機のみで可能となるため、従来の焙焼法や研磨再生法等に比べ設備がシンプル化でき、臭気・粉塵発生もなく省エネ化も進み、画期的なコスト削減が可能となる。 When dewatering, a conventional sand kneading apparatus is not necessary because a cast sand in a kneaded sand state can be obtained by using a centrifuge and a solution having a predetermined concentration. Therefore, the sand measurement accompanying the sand kneading, the measurement of the binder, and the charging device are not required. In addition, since the binder adhering to the core can be dissolved in water and then uniformly adhered to the surface of the foundry sand, the binder can be reused very easily and can be recycled with an efficiency of nearly 100%. In addition, since the main regenerator can only be a centrifuge, the equipment can be simplified compared to the conventional roasting method and polishing regenerating method, etc., no odor and dust are generated, energy saving is advanced, and epoch-making cost Reduction is possible.
本発明で用いられる鋳物砂粒子は、従来知られたものを用いることができる。具体的には、ＳｉＣ、アルミナ、ムライト、シリカ、ジルコン等を用いることが好ましい。これらは、優れた強度、低熱膨張率を有するとともに入手が比較的容易であり、強度、寸法精度等に優れた水溶性中子を製造することができる。 As the foundry sand particles used in the present invention, those conventionally known can be used. Specifically, it is preferable to use SiC, alumina, mullite, silica, zircon or the like. These have excellent strength and low thermal expansion coefficient and are relatively easily available, and can produce a water-soluble core excellent in strength, dimensional accuracy, and the like.
本発明で用いられる水溶性無機バインダーは限定されないが、特に、マグネシウムイオン（Ｍｇ２＋）、ナトリウムイオン（Ｎａ＋）、カルシウムイオン（Ｃａ２＋）から選択されるカチオンと、ＳＯ４ ２−、ＣＯ３ ２−、ＨＣＯ３ ２−、Ｂ４Ｏ７ −から選択されるアニオンとの組み合わせからなる水溶性無機塩の１種以上を用いることで、十分な中子強度と水可溶性を併せ持つ水溶性中子を得ることができる。その中でも、硫酸マグネシウム（ＭｇＳＯ４）が好ましい。又、水溶性無機塩として、硫酸マグネシウム（ＭｇＳＯ４）０〜１００重量％と、炭酸ナトリウム（Ｎａ２ＣＯ３）、４ホウ酸ナトリウム（Ｎａ２Ｂ４Ｏ７）、硫酸ナトリウム（Ｎａ２ＳＯ４）から選択される１種以上１００〜０重量％からなる混合系も好ましい。この水溶性中子を用いることで、鋳造時に型崩れせず、鋳造後の砂落しが水圧で容易に行うことができる。 The water-soluble inorganic binder used in the present invention is not limited, and in particular, a cation selected from magnesium ion (Mg 2+ ), sodium ion (Na + ), calcium ion (Ca 2+ ), SO 4 2− , CO 3. A water-soluble core having both sufficient core strength and water solubility by using one or more water-soluble inorganic salts composed of a combination of an anion selected from 2- , HCO 3 2− , and B 4 O 7 — Can be obtained. Among these, magnesium sulfate (MgSO 4 ) is preferable. As water-soluble inorganic salts, magnesium sulfate (MgSO 4 ) 0 to 100% by weight, sodium carbonate (Na 2 CO 3 ), sodium borate (Na 2 B 4 O 7 ), sodium sulfate (Na 2 SO 4) A mixed system consisting of one or more selected from 100 to 0% by weight is also preferred. By using this water-soluble core, it does not lose its shape during casting, and sand removal after casting can be easily performed with water pressure.
本発明の水溶性中子では、鋳物砂に対する無機塩バインダー添加量の合計量は０．８〜１０重量％であることが好ましく、４〜７重量％であることがより好ましい。 In the water-soluble core of the present invention, the total amount of the inorganic salt binder added to the foundry sand is preferably 0.8 to 10% by weight, and more preferably 4 to 7% by weight.
又、本発明では、鋳物砂粒子の表面が無機塩バインダーで被覆され、該鋳物砂粒子の隙間に無機微粉末が充填された水溶性中子を用いることが出来る。無機微粉末を充填させることで、水溶性中子の流動性と充填性を低下させずに、強度を向上させることが出来る。無機微粉末としては、カオリン、タルクが好ましく例示される。鋳物砂に対して、水溶性無機塩バインダー４〜７％、無機微粉末が１〜７％であることが好ましい。 Further, in the present invention, a water-soluble core in which the surface of the foundry sand particles is coated with an inorganic salt binder and an inorganic fine powder is filled in the gap between the foundry sand particles can be used. By filling the inorganic fine powder, the strength can be improved without lowering the fluidity and filling property of the water-soluble core. Preferred examples of the inorganic fine powder include kaolin and talc. It is preferable that the water-soluble inorganic salt binder is 4 to 7% and the inorganic fine powder is 1 to 7% with respect to the foundry sand.
又、本発明では、水溶性無機塩バインダーに、珪砂（珪粉）、アルミナ、チタン酸カリウム、炭化珪素、珪酸ジルコン、繊維状チタン酸カリウム、酸化チタン、酸化亜鉛、酸化鉄、酸化マグネシウムから選択される無機フィラーの１種以上を添加することが出来る。無機フィラーを添加することで、高温強度と、砂落しの容易性の目安となる水可溶性を併せ持つ水溶性中子が得られる。 In the present invention, the water-soluble inorganic salt binder is selected from silica sand (silica powder), alumina, potassium titanate, silicon carbide, zircon silicate, fibrous potassium titanate, titanium oxide, zinc oxide, iron oxide and magnesium oxide. One or more inorganic fillers can be added. By adding an inorganic filler, a water-soluble core having both high-temperature strength and water-solubility that is a measure of ease of sand removal can be obtained.
本発明の水溶性中子では、前記無機フィラーを添加する場合は鋳物砂に対して０．２〜１０重量％であることが好ましい。 In the water-soluble core of the present invention, when the inorganic filler is added, the content is preferably 0.2 to 10% by weight based on the foundry sand.
以下、本発明の実施例を図面を用いて説明する。 Embodiments of the present invention will be described below with reference to the drawings.
図１に、本発明の鋳物砂及び水溶性無機塩バインダーの再利用装置の概略を示す。砂落装置１に、鋳物砂粒子の表面が水溶性無機塩バインダーで被覆された水溶性中子を用いた鋳造品（砂付粗材）をセットし、この鋳造品（砂付粗材）に対して、噴射装置２から水溶性無機塩バインダー及び水からなる上澄み液を噴射する。水溶性バインダーで成型された中子は、噴射された水溶液によって成型力を失い、鋳造品（砂付粗材）から流出する。この際、中子に付着していた水溶性バインダーは溶液内に溶ける。鋳造品（砂付粗材）から中子砂を完全に流出させるには、鋳造品（砂付粗材）を回転させたり、水溶液の噴射圧力を上げたり、超音波を照射する等の手段を併用することも有効である。水圧を用いて砂落装置１で除去された鋳物砂、水溶性無機塩バインダー及び水からなる混合物は落下し、砂落装置１の下方に配置された砂沈殿槽３に貯蔵される。砂沈殿槽３において、鋳物砂、水溶性無機塩バインダー及び水からなる混合物は、水溶性無機塩バインダー及び水からなる上澄み液と、主として鋳物砂からなり少量の水溶性無機塩バインダー及び水からなるスラリーに分離する。上澄み液（水溶性無機塩バインダー水溶液）は隣接する溶液バッファー槽４に貯蔵される。溶液バッファー槽４の上澄み液（水溶性無機塩バインダー水溶液）は、ポンプを介して配管により噴射装置２に導かれ、鋳物砂の除去に繰返し再利用される。一方、砂沈殿槽３で沈殿したスラリーは、砂沈殿槽３の下部よりスラリーポンプを介して脱水装置５へ送られる。脱水装置５としては、遠心分離機が有効である。遠心分離機は６００〜１８００Ｇ程度の遠心力を持たせ、砂と溶液に分離する。遠心力により飛ばされた水溶液は砂沈殿槽３へ戻される。脱水装置５で所定濃度まで脱水されたスラリーは、鋳物砂が所定の溶液を含んだ湿砂状態（混練砂状態）となるから、このまま次工程の造型機へ送られ再利用される。遠心分離機を利用すると、砂の種類やフィルターの種類を選定することにより、ある遠心力以上で一定の残留水分とすることが出来る。
In FIG. 1, the outline of the reuse apparatus of the foundry sand and water-soluble inorganic salt binder of this invention is shown. In the sand drop device 1, a cast product (a coarse material with sand) using a water-soluble core whose surface of the casting sand particles is coated with a water-soluble inorganic salt binder is set, and this cast product (the coarse material with sand) is set. On the other hand, a supernatant liquid composed of a water-soluble inorganic salt binder and water is jetted from the
図１では、配管６により、脱水装置５で脱水溶液である水溶性無機塩バインダー水溶液を砂沈殿槽３へ導いている。又、溶液バッファー槽４に、蒸発等で損失する補給水を添加する手段７を有している。なお、砂落し条件を安定化するため、ヒーターやクーラー等の溶液温度を一定にする手段を加えることも有効である。
In FIG. 1, a water-soluble inorganic salt binder aqueous solution that is a dewatered solution is guided to the
図２に本発明の実施例のシステムフロー図を示す。本実施例では、脱水を１回行っている。又、図３に本発明の他の実施例のシステムフロー図を示す。本実施例では、脱水を２回行っている。 FIG. 2 shows a system flow diagram of an embodiment of the present invention. In this embodiment, dehydration is performed once. FIG. 3 shows a system flow diagram of another embodiment of the present invention. In this embodiment, dehydration is performed twice.
１：砂落装置、２：噴射装置、３：砂沈殿槽、４：溶液バッファー槽、５：脱水装置、６：脱水溶液を導く配管、７：補給水添加手段。 1: sand dropping device, 2: jetting device, 3: sand sedimentation tank, 4: solution buffer tank, 5: dewatering device, 6: piping for dewatering, 7: makeup water adding means.
Claims (12)
In an aluminum alloy casting method including a core molding step, a casting step, and a sand dropping step, the foundry sand and the water-soluble inorganic salt binder recovered by the method according to any one of claims 1 to 7 in the core molding step. An aluminum alloy casting method characterized by being reused.
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|---|---|---|---|---|
| CN102773465A (en) * | 2012-07-26 | 2012-11-14 | 无锡蠡湖叶轮制造有限公司 | Automatic water-saving degritting device |
| CN104959531A (en) * | 2015-07-22 | 2015-10-07 | 平顶山市沙河机械加工厂 | Waste foundry sand dealkalizing regenerative production equipment |
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| JP2005138141A (en) | 2005-06-02 |
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