JP2008156171A

JP2008156171A - Inorganic molded product

Info

Publication number: JP2008156171A
Application number: JP2006348319A
Authority: JP
Inventors: Tatsuo Ito; 達雄井東; Naoharu Nakagawa; 尚治中川
Original assignee: Matsushita Electric Works Ltd
Current assignee: Panasonic Electric Works Co Ltd
Priority date: 2006-12-25
Filing date: 2006-12-25
Publication date: 2008-07-10

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inorganic molded product whose freeze damage resistance and strength are enhanced by reusing a recovered inorganic filler as a filler. <P>SOLUTION: The inorganic molded product is molded by hardening cement containing the inorganic filler obtained by decomposing plastic containing the inorganic filler with subcritical water or supercritical water. The degradation of the inorganic molded product is suppressed by that the recessed and projected surface of a glass fiber contained in the inorganic filler becomes a water interference part in volume expansion. The strength of the inorganic molded product itself is enhanced by the glass fiber itself contained in the inorganic filler. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

本発明は、無機充填材を含有するプラスチックを熱分解温度以下の温度の亜臨界水又は超臨界水を用いて分解することにより得られた無機充填材をセメント系成形品の無機充填材として再利用する技術に関する。 In the present invention, an inorganic filler obtained by decomposing a plastic containing an inorganic filler using subcritical water or supercritical water having a temperature equal to or lower than the thermal decomposition temperature is reused as an inorganic filler of a cement-based molded article. It relates to the technology used.

従来、プラスチック廃棄物はその殆どが埋立処分又は焼却処理されており、資源として有効活用されていなかった。また埋立処分では埋立用地の確保が困難なことや埋立後の地盤が不安定になるという問題があり、焼却処理では炉の損傷，有害ガスや悪臭の発生，ＣＯ₂排出といった問題がある。このため、平成７年に容器包装廃棄物法が制定され、プラスチックの回収，再利用が義務付けられるようになった。さらに、各種リサイクル法の施行に伴いプラスチックを含む製品の回収リサイクルの流れは加速する傾向にある。 Conventionally, most plastic waste has been landfilled or incinerated, and has not been effectively utilized as a resource. In addition, landfill disposal has problems such as difficulty in securing landfill site and unstable land after landfill, and incineration has problems such as furnace damage, generation of harmful gases and odors, and CO ₂ emissions. For this reason, the Containers and Packaging Waste Law was enacted in 1995, and plastics must be collected and reused. Furthermore, with the enforcement of various recycling laws, the flow of collection and recycling of products containing plastics tends to accelerate.

これらの状況に合わせて、近年、プラスチック廃棄物を再資源化することが試みられており、その一つの方法として、超臨界水を反応媒体とする反応によりプラスチック廃棄物を分解油化し、有用な油状物を回収する方法が提案されている（特許文献１参照）。また各種構造材料に使用される繊維強化プラスチックについては、超臨界水又は亜臨界水を用いてプラスチック成分を分解し、ガラス繊維や炭素繊維等の繊維を回収，再利用する方法が提案されている（特許文献２参照）。 In recent years, it has been attempted to recycle plastic waste in accordance with these situations. As one method, plastic waste is decomposed into oil by a reaction using supercritical water as a reaction medium, and useful. A method for recovering an oily substance has been proposed (see Patent Document 1). For fiber reinforced plastics used in various structural materials, a method has been proposed in which plastic components are decomposed using supercritical water or subcritical water, and fibers such as glass fibers and carbon fibers are recovered and reused. (See Patent Document 2).

これらの方法では、プラスチックは分解により低分子化した油状成分となり主に液体燃料として再利用される。また、高温水蒸気による加水分解反応を利用した分解方法も提案されており、この方法によれば熱可塑性プラスチック及び熱硬化性プラスチックの有機高分子成分を一応分解することができる。また、ジカルボン酸，ジアミン等の分解用成分を用いて硬化不飽和ポリエステル樹脂廃棄物を分解して樹脂原料を得て、不飽和ポリエステル樹脂を再合成するケミカルリサイクル法も提案されている（特許文献３参照）。 In these methods, plastic becomes an oily component having a low molecular weight by decomposition, and is mainly reused as a liquid fuel. In addition, a decomposition method using a hydrolysis reaction with high-temperature steam has been proposed, and according to this method, the organic polymer component of the thermoplastic plastic and the thermosetting plastic can be decomposed once. In addition, a chemical recycling method is proposed in which a cured raw material is obtained by decomposing a cured unsaturated polyester resin waste using a decomposition component such as a dicarboxylic acid or a diamine (Patent Document). 3).

しかしながら、超臨界法では、プラスチックをランダムに分解するため、分解生成物が多種成分からなる油状物質となり、一定品質の分解生成物を得ることが困難である。このため、ゼオライトに代表される触媒を用いて油質の改質を行なう等の後処理が必要となってコスト高になり、また改質した生成油においても灯油や軽油等の石油製品そのものにすることは困難であるので、実用化には至っていない。また、特許文献３記載の方法では、分解後の樹脂を再度不飽和ポリエステル樹脂として再利用しているものの、分解温度が高く、熱分解を起こしているために、再硬化させた際の物性が本来の不飽和ポリエステル樹脂とは異なる（熱硬化性樹脂としては低下する）ことや再硬化品に占める分解樹脂の利用率が低いことが問題となる。 However, in the supercritical method, since the plastic is decomposed randomly, the decomposition product becomes an oily substance composed of various components, and it is difficult to obtain a decomposition product of a certain quality. For this reason, post-treatment such as reforming of oil quality using a catalyst typified by zeolite is required, resulting in high costs, and the modified product oil is also used in petroleum products such as kerosene and light oil. Since it is difficult to do so, it has not been put into practical use. Further, in the method described in Patent Document 3, although the resin after decomposition is reused again as an unsaturated polyester resin, the decomposition temperature is high and thermal decomposition occurs. There is a problem that it is different from the original unsaturated polyester resin (decreases as a thermosetting resin) and the utilization rate of the decomposition resin in the recured product is low.

そこで、本願発明の発明者らは、不飽和ポリエステル樹脂とその架橋部からなる熱硬化性樹脂を含むプラスチックを亜臨界水にてプラスチックの熱分解温度以下の温度で分解し、再利用できる形で分解，回収する方法を提案した（特許文献４参照）。この方法では、不飽和ポリエステル樹脂の原料として再利用できるモノマー，架橋部と有機酸の共重合体等が生成されるが、それ以外に無機充填材である炭酸カルシウム，ガラス繊維等が分解されずにそのまま残留する。これらの無機充填材はＳＭＣ（Sheet Molding Compound）の充填材，他の建材用の充填材として利用されつつあるが、その利用量は少ないというのが現状である（特許文献５参照）。
特開平６−２７９７６２号公報特開平１０−８７８７２号公報特開平９−２２１５６５号公報国際公開第０５／９２９６２号パンフレット特開２００６−２３１６４１号公報 Therefore, the inventors of the present invention decomposed a plastic containing an unsaturated polyester resin and a thermosetting resin composed of a crosslinked portion thereof with subcritical water at a temperature lower than the thermal decomposition temperature of the plastic, and can be reused. A method of decomposition and recovery was proposed (see Patent Document 4). In this method, a monomer that can be reused as a raw material for the unsaturated polyester resin, a copolymer of a crosslinked portion and an organic acid, and the like are produced, but other than that, calcium carbonate, glass fiber, etc., which are inorganic fillers, are not decomposed. It remains as it is. These inorganic fillers are being used as fillers for SMC (Sheet Molding Compound) and fillers for other building materials, but the amount used is currently small (see Patent Document 5).
JP-A-6-279762 Japanese Patent Laid-Open No. 10-87872 Japanese Patent Laid-Open No. 9-221565 WO05 / 92962 pamphlet JP 2006-231641 A

本発明は、上記課題を解決するためになされたものであり、その目的は、無機充填材を含有するプラスチックを熱分解温度以下の温度の亜臨界水又は超臨界水を用いて分解することにより回収された無機充填材を充填材として再利用して耐凍害性能及び強度を向上させた無機成形品を提供することにある。 The present invention has been made in order to solve the above-described problems, and its purpose is to decompose a plastic containing an inorganic filler using subcritical water or supercritical water having a temperature equal to or lower than the thermal decomposition temperature. An object of the present invention is to provide an inorganic molded article that is improved in frost resistance and strength by reusing the collected inorganic filler as a filler.

無機充填材に含まれるガラス繊維は、高温，高圧，高アルカリである亜臨界水又は超臨界水に接触すると、その表面の一部が浸食されることによってクレーター状の凹凸を生じる。一方、特に寒冷地では、水は、セメント系建材内への侵入，凍結（膨張）を繰り返すことによってセメント系建材に劣化を生じさせる。このようなセメント系建材にガラス繊維を含有する無機充填材を混入させると、セメント系建材中に侵入した水が表面から凍結し、その体積を増やそうとして内向圧力が生じ、その周囲を圧迫する。この圧力によって凍結していない水は、透過できるセメント部分を通って近くの空隙に押しやられ、水で満たされていない空隙に達すると圧力が軽減するので、その付近のセメントは損傷されない。すなわちガラス繊維表面の凹凸が、体積膨張時の水の干渉部となり、その劣化を抑制する。また、無機充填材に含まれているガラス繊維自身によってセメント成形品自体の強度も向上する。従って、本発明に係る無機成形品によれば、回収された無機充填材を充填材として再利用して耐凍害性能及び強度を向上させた無機成形品を提供することができる。 When the glass fiber contained in the inorganic filler comes into contact with subcritical water or supercritical water, which is high temperature, high pressure, and high alkali, a part of its surface is eroded, resulting in crater-like irregularities. On the other hand, particularly in cold regions, water causes deterioration in cement-based building materials by repeatedly entering and freezing (expanding) into cement-based building materials. When an inorganic filler containing glass fiber is mixed in such a cement-based building material, water that has entered the cement-based building material freezes from the surface, generating inward pressure to increase its volume and compressing its surroundings. . This pressure causes unfrozen water to be pushed through the permeable cement portion into the nearby voids and, when reaching the voids not filled with water, the pressure is relieved so that the nearby cement is not damaged. That is, the irregularities on the surface of the glass fiber become an interference part of water at the time of volume expansion and suppress the deterioration. Further, the strength of the cement molded product itself is improved by the glass fiber itself contained in the inorganic filler. Therefore, according to the inorganic molded product according to the present invention, it is possible to provide an inorganic molded product in which the recovered inorganic filler is reused as a filler to improve the frost resistance and strength.

以下、本発明を実施例に基づき詳しく説明する。 Hereinafter, the present invention will be described in detail based on examples.

〔実施例１〕
実施例１では、始めに、無機充填材を含有するＦＲＰ製浴槽を２［ｍｍ］アンダーまで粉砕することによりＦＲＰを得る。次に、圧力容器中にＦＲＰ６５０［ｇ］，水２５１５［ｇ］，及びＮａＯＨ８５［ｇ］を入れ、混合，攪拌しながら２３０［℃］まで加温して４時間保持する。次に、圧力容器を室温まで冷却した後、圧力容器から分解後の溶液（分解液）を取り出し、濾過装置（フィルタープレス）により分解液を固形分（無機充填材）と液体に分離する。次に、濾過装置から固形分を取り出し、塊砕，乾燥，粉砕することにより無機充填材を回収する。なお、分離された液体については次工程に移行して各々生成物を分離，回収する。次に、回収された無機充填材１０重量部，セメント４０重量部，フライアッシュ４０重量部，珪石粉１０重量部，及びパルプ１０重量部を攪拌，混合した後、水５０重量部を加えて攪拌，混合する。そして最後に金型を用いて混合された材料を押出成形し、養生，硬化させてセメント系成形板を得た。 [Example 1]
In Example 1, first, FRP is obtained by pulverizing an FRP bathtub containing an inorganic filler to under 2 [mm]. Next, FRP 650 [g], water 2515 [g], and NaOH 85 [g] are put in a pressure vessel, heated to 230 [° C.] with mixing and stirring, and held for 4 hours. Next, after cooling the pressure vessel to room temperature, the decomposed solution (decomposed solution) is taken out from the pressure vessel, and the decomposed solution is separated into a solid (inorganic filler) and a liquid by a filtration device (filter press). Next, the solid content is taken out from the filtration device, and the inorganic filler is recovered by crushing, drying and crushing. In addition, about the isolate | separated liquid, it transfers to a next process and each product is isolate | separated and collect | recovered. Next, 10 parts by weight of the recovered inorganic filler, 40 parts by weight of cement, 40 parts by weight of fly ash, 10 parts by weight of silica powder, and 10 parts by weight of pulp were stirred and mixed, and then 50 parts by weight of water was added and stirred. , Mix. Finally, the mixed material was extruded using a mold, and cured and cured to obtain a cement-based molded plate.

〔実施例２〕
実施例２では、実施例１と同様の方法で無機充填材を回収した後、回収された無機充填材１０重量部，セメント４０重量部，フライアッシュ４０重量部，珪石粉１０重量部，及びパルプ１０重量部を攪拌，混合し、さらにスラリー濃度が１０％になるように水を加えて攪拌，混合する。そして最後に、スラリーを抄造し、金型を用いて表面に模様を付与し、養生，硬化させてセメント系成形板を得た。 [Example 2]
In Example 2, after recovering the inorganic filler by the same method as in Example 1, 10 parts by weight of the recovered inorganic filler, 40 parts by weight of cement, 40 parts by weight of fly ash, 10 parts by weight of silica powder, and pulp 10 parts by weight is stirred and mixed, and water is further added and stirred and mixed so that the slurry concentration becomes 10%. Finally, the slurry was made, a pattern was applied to the surface using a mold, and the cement was formed by curing and curing.

〔比較例１〕
比較例１では、セメント４０重量部，フライアッシュ４０重量部，珪石粉１０重量部，及びパルプ１０重量部を攪拌，混合した後、水５０重量部を加えて攪拌，混合する。そして最後に金型を用いて混合された材料を押出成形し、養生，硬化させてセメント系成形板を得た。 [Comparative Example 1]
In Comparative Example 1, 40 parts by weight of cement, 40 parts by weight of fly ash, 10 parts by weight of silica powder, and 10 parts by weight of pulp are stirred and mixed, and then 50 parts by weight of water is added and stirred and mixed. Finally, the mixed material was extruded using a mold, and cured and cured to obtain a cement-based molded plate.

〔比較例２〕
比較例２では、セメント４０重量部，フライアッシュ４０重量部，珪石粉１０重量部，及びパルプ１０重量部を攪拌，混合した後、スラリー濃度が１０％になるように水を加えて攪拌，混合する。そして最後に、スラリーを抄造し、金型を用いて表面に模様を付与し、養生，硬化させてセメント系成形板を得た。 [Comparative Example 2]
In Comparative Example 2, 40 parts by weight of cement, 40 parts by weight of fly ash, 10 parts by weight of silica stone powder, and 10 parts by weight of pulp were stirred and mixed, and then water was added and stirred and mixed so that the slurry concentration became 10%. To do. Finally, the slurry was made, a pattern was applied to the surface using a mold, and the cement was formed by curing and curing.

〔評価〕
上記実施例１，２及び比較例１，２のセメント系成形板について、凍結溶解試験を２００サイクル実施した後の体積膨張率［％］及び曲げ強度（ＭＰａ）を評価した結果を表１に示す。表１に示すように、実施例１，２のセメント系成形板は、比較例１，２のセメント系成形板と比較して、凍結溶解試験を２００サイクル実施した後の体積膨張率及び曲げ強度が優れていることが確認された。

[Evaluation]
Table 1 shows the results of evaluating the volume expansion rate [%] and bending strength (MPa) of the cement-based molded plates of Examples 1 and 2 and Comparative Examples 1 and 2 after 200 cycles of the freeze-thaw test. . As shown in Table 1, the cement-based molded plates of Examples 1 and 2 were compared with the cement-based molded plates of Comparative Examples 1 and 2, and the volume expansion coefficient and bending strength after 200 cycles of the freeze / thaw test. Was confirmed to be excellent.

以上、本発明者らによってなされた発明を適用した実施の形態について説明したが、この実施の形態による本発明の開示の一部をなす論述及び図面により本発明は限定されることはない。すなわち、上記実施の形態に基づいて当業者等によりなされる他の実施の形態、実施例及び運用技術等は全て本発明の範疇に含まれることは勿論であることを付け加えておく。 As mentioned above, although the embodiment to which the invention made by the present inventors was applied has been described, the present invention is not limited by the description and the drawings that form part of the disclosure of the present invention according to this embodiment. That is, it should be added that other embodiments, examples, operation techniques, and the like made by those skilled in the art based on the above embodiments are all included in the scope of the present invention.

Claims

An inorganic molded article obtained by curing a cement containing an inorganic filler obtained by decomposing a plastic containing an inorganic filler using subcritical water or supercritical water.

2. The inorganic molded article according to claim 1, wherein the cement contains glass fibers as the inorganic filler.