JP2007240093A - Solid fuel combustion device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a solid fuel combustion device with compact size and high heat recovery efficiency usable for a hot water/hot air/vapor generator, which can efficiently recover combustion ash or unburnt fine particles resulted from burning of solid fuel. <P>SOLUTION: This combustion device has the following structure. In a hot water/hot air/vapor generator having a combustion chamber 1 for burning solid fuel in the center of the generator, a swirl upward flow of combustion gas containing combustion ash or unburnt fine particles resulted from combustion of the solid fuel in the lower part of the combustion chamber 1 is guided to the upper part of the combustion chamber 1 while recovering heat in the inner wall of a heat exchanger inner cylinder 6 and a central column pipe 5, passed through a water pipe 8 provided in the upper part of the heat exchanger inner cylinder 6, and cooled while letting down in a double cylindrical fire tube 2 formed by the inner wall of a heat exchanger outer cylinder 7 and the outer wall of the heat exchanger inner cylinder 6. The flow velocity is reduced by reduction in unit volume and passage extension in an ash basin chamber 3, and separation/capture efficiency in the ash basin chamber 3 is raised by inverting the flow from the ash basin chamber 3 to a fire tube 4, whereby the ash basin chamber 3 can be made compact. Further, heat recovery can be enhanced by constituting the ash basin chamber 3 also by use of a water-cooled wall. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

本発明はバイオマスや廃棄物等の固形燃料を燃焼するための固形燃焼装置に関し、更に詳しくは固形燃料を燃焼したときに生成する灰分や未燃固形分を簡単な構造で回収し、保守を容易にする固形燃料燃焼装置に関する。   The present invention relates to a solid combustion apparatus for burning solid fuel such as biomass and waste, and more particularly, ash and unburned solid generated when the solid fuel is burned is recovered with a simple structure and easy to maintain. The present invention relates to a solid fuel combustion apparatus.

従来より、固形燃料を燃焼する方式としては火格子燃焼方式の燃焼装置があるが、この方式では火格子上に残る燃焼灰の除去にプッシャーやレーキを使い、定期的に掻き出す必要があり、かつ構造が複雑な燃焼装置であった。   Conventionally, there is a grate combustion type combustion device as a method of burning solid fuel, but in this method it is necessary to use a pusher or rake to remove the combustion ash remaining on the grate and scrape it periodically, and It was a combustor with a complicated structure.

また、この問題を解決するため、近年、燃焼室の固定火格子上に供給される固形燃料を燃焼室下層の燃焼空気供給室から噴出さす強い旋回空気で固体燃料を移動させながら燃焼し、かつ、未燃粒子や燃焼時に生成する燃焼灰を中央に移動させ、燃焼室中央に設けた円筒部材を通じて、燃焼空気供給室下層にある燃焼灰回収部に誘導・分離・除去する装置が提案されている。（例えば、特許文献１参照。）   In order to solve this problem, in recent years, the solid fuel supplied onto the fixed grate of the combustion chamber is burned while moving the solid fuel with strong swirling air ejected from the combustion air supply chamber below the combustion chamber, and An apparatus has been proposed that moves unburned particles and combustion ash generated during combustion to the center, and guides, separates, and removes them to the combustion ash recovery section in the lower layer of the combustion air supply chamber through a cylindrical member provided in the center of the combustion chamber. Yes. (For example, refer to Patent Document 1.)

また、燃焼室中央に設けた上記円筒部を燃焼室炉床より高くし、燃焼空気供給室下層にある分離回収部に燃焼灰を燃焼ガスで同伴させて、燃焼灰の連続回収と固形燃料の燃焼向上を図る装置が提案されている。（例えば、特許文献２参照。）
実用新案登録第３０９９２２４号 特願２００５−３３７６０１ In addition, the cylindrical part provided in the center of the combustion chamber is made higher than the combustion chamber hearth, and combustion ash is accompanied by combustion gas in the separation and recovery part in the lower layer of the combustion air supply chamber, so that continuous recovery of combustion ash and solid fuel Devices for improving combustion have been proposed. (For example, see Patent Document 2.)
Utility model registration No. 3099224 Japanese Patent Application No. 2005-337601

特許文献１の燃焼装置では固形燃料を移動するに必要な燃焼空気の旋回力が強く、燃焼ガスに同伴される燃焼灰が多くなり、下流の熱交換部の耐火材上や煙管内に堆積しやすくなるため、熱交換効率を低下し、保守頻度が高くなる。   In the combustion apparatus of Patent Document 1, the swirl force of combustion air necessary for moving solid fuel is strong, and the combustion ash accompanying the combustion gas increases, which accumulates on the refractory material in the downstream heat exchange section and in the smoke pipe. Since it becomes easy, heat exchange efficiency falls and maintenance frequency becomes high.

特許文献２の燃焼装置では分離回収室に入る燃焼ガス温度が高く、分離回収部の容積を大きくとらないと十分な分離・回収が期待できない。 In the combustion apparatus of Patent Document 2, the temperature of the combustion gas entering the separation and recovery chamber is high, and sufficient separation and recovery cannot be expected unless the volume of the separation and recovery part is increased.

本発明は燃焼灰の回収を効率よく行い、かつコンパクトな形状の温水・熱風・蒸気発生器に使用できる固体燃焼装置を提供することにある。   It is an object of the present invention to provide a solid combustion apparatus that efficiently collects combustion ash and can be used in a hot water / hot air / steam generator having a compact shape.

本発明の燃焼装置は燃焼室で固体燃料が燃焼して出来た燃焼排ガスと燃焼灰や未燃微粒子の混合ガスが燃焼室内の中央を走る水管および燃焼室水壁で熱交換しながら温度を下げ、燃焼室上部を出たガスは燃焼室と同軸の2重円筒煙管を降下する過程で更に温度を下げ、ガス流速を低下することにより、燃焼灰分離室（以下灰溜り室と呼ぶ）での灰の同伴力を弱くし分離・回収を良くすることを特徴とする。   The combustion apparatus of the present invention lowers the temperature while exchanging heat between the combustion exhaust gas produced by burning solid fuel in the combustion chamber and the mixed gas of combustion ash and unburned particulates in the water pipe and combustion chamber water wall running in the center of the combustion chamber. The gas that exits the upper part of the combustion chamber is further lowered in the process of descending the double cylindrical smoke tube coaxial with the combustion chamber, and the gas flow rate is lowered to reduce the gas flow rate in the combustion ash separation chamber (hereinafter referred to as the ash chamber). It is characterized by weaker ash entrainment and better separation and recovery.

この装置に切り替えると燃焼灰の分離・回収が良くなり、煙管の保守点検頻度が下がるだけでなく、灰溜り容積が減少し、装置全体がコンパクトになる。また、あらゆるところが水冷壁で囲まれるため、熱回収効率も良くなる。   Switching to this device not only improves the separation and recovery of combustion ash, reduces the frequency of maintenance and inspection of the smoke pipe, but also reduces the ash accumulation volume, making the entire device compact. In addition, since all parts are surrounded by water-cooled walls, the heat recovery efficiency is improved.

本発明による燃焼装置の具体的な実施例として温水発生器に適用した形態について、図面を参照しながら説明する。   The form applied to the hot water generator as a specific embodiment of the combustion apparatus according to the present invention will be described with reference to the drawings.

固形燃料は固形燃料投入口１６から燃焼室１に投入され、燃焼空気室１０から燃焼室１下部のロストル９を通じて吹き込まれる強い旋廻流である燃焼空気により、ロストル上を移動しながら燃焼する。このとき、燃料に含まれる灰分は燃焼灰として、また、未燃の粉体や燃焼途中の微粒子の一部も燃焼ガスとともに燃焼室１内を上昇していく。   The solid fuel is introduced into the combustion chamber 1 from the solid fuel inlet 16 and burns while moving on the rooster by the combustion air which is a strong whirling flow blown from the combustion air chamber 10 through the rooster 9 below the combustion chamber 1. At this time, the ash contained in the fuel rises in the combustion chamber 1 as combustion ash, and unburned powder and some of the fine particles in the course of combustion rise together with the combustion gas.

燃焼室１で発生した高温の燃焼ガスは燃焼灰等の微粒子を同伴したまま中央水柱管５の周りを旋回上昇し、燃焼室１を囲む熱交換器内筒６および燃焼室の中央水柱管５との熱交換をしながら、熱交換器内筒上部の水管８の間を抜け、熱交換器内筒６と熱交換器外筒７がつくる２重円筒煙管２に入る。   The high-temperature combustion gas generated in the combustion chamber 1 swirls and rises around the central water column pipe 5 accompanied by fine particles such as combustion ash, and the heat exchanger inner cylinder 6 surrounding the combustion chamber 1 and the central water column pipe 5 of the combustion chamber. While exchanging heat with each other, the heat exchanger passes through the water pipe 8 at the upper part of the inner cylinder of the heat exchanger and enters the double cylindrical smoke pipe 2 formed by the inner cylinder 6 of the heat exchanger and the outer cylinder 7 of the heat exchanger.

２重円筒煙管２に入った燃焼ガスは熱交換器外筒７の内側壁と熱交換器内筒６の外側壁からなる水冷壁で更に冷却されながら下降し、灰溜り室３に入る。   The combustion gas that has entered the double cylindrical smoke tube 2 descends while being further cooled by a water-cooled wall composed of the inner wall of the heat exchanger outer cylinder 7 and the outer wall of the heat exchanger inner cylinder 6, and enters the ash storage chamber 3.

灰溜り室３に入った燃焼ガスはこれまでの熱交換で温度が下がり、単位体積が小さくなるだけでなく、流路断面が広がるため、流速を落とし、燃焼灰微粒子の同伴力が小さくなる。更に、煙管４に入るために方向を変えることで、ますます粒子を分離し易くなるため、における粒子の捕捉・分離の効率がよくなり、灰溜り室３がコンパクトですむ。   The combustion gas that has entered the ash storage chamber 3 is not only reduced in temperature and reduced in unit volume due to the heat exchange so far, but also the cross section of the flow path is widened, so the flow velocity is reduced and the accompanying force of the combustion ash particulates is reduced. Further, by changing the direction to enter the smoke pipe 4, it becomes easier to separate the particles, so that the efficiency of capturing and separating the particles is improved, and the ash chamber 3 is compact.

灰溜り室３で灰を分離した燃焼ガスは熱交換器外筒内の煙管４を通り、熱交換しながら煙室２０に入り煙出口２１機外に排出される。   The combustion gas from which the ash is separated in the ash storage chamber 3 passes through the smoke pipe 4 in the outer tube of the heat exchanger, enters the smoke chamber 20 and is discharged outside the smoke outlet 21 while exchanging heat.

機外から戻る温水は温水戻り口１３から熱交換器外筒７に入り煙管で加熱されながら上昇し、燃焼室中央に位置する中央水柱管５に入り、高温の燃焼ガスで加熱されながら下降し、中央水柱管５底部の分配口１８から熱交管内筒６に入り、上昇しながら燃焼室１燃焼ガスおよび２重円筒煙管２を流れる燃焼排ガスで更に加熱され、温水器上部のヘッダー１９から温水出口１４を通り機外へと送られる。   Hot water returning from outside the machine enters the heat exchanger outer cylinder 7 from the hot water return port 13 and rises while being heated by the smoke pipe, enters the central water column pipe 5 located at the center of the combustion chamber, and descends while being heated by the high-temperature combustion gas. From the distribution port 18 at the bottom of the central water column pipe 5, it enters the heat exchanger tube inner cylinder 6 and is further heated by the combustion exhaust gas flowing through the combustion chamber 1 combustion gas and the double cylindrical smoke pipe 2 while ascending, and is heated from the header 19 at the top of the water heater. It is sent to the outside through the exit 14.

燃焼室１に残った燃焼灰や未燃焼固形分、灰溜り室３で回収された燃焼灰や未燃微粒子は運転終了後、燃焼室点検口１１と灰掻き出し口１２から定期的に掻き出される。   The combustion ash and unburned solids remaining in the combustion chamber 1 and the combustion ash and unburned fine particles collected in the ash storage chamber 3 are periodically scraped from the combustion chamber inspection port 11 and the ash scraping port 12 after the operation is completed. .

また、燃焼室１、灰溜り室３とも水冷壁で囲まれるため、機器全体の熱回収効率も上がる。   In addition, since both the combustion chamber 1 and the ash storage chamber 3 are surrounded by water cooling walls, the heat recovery efficiency of the entire device is also increased.

固形燃料焚き温水ボイラの上部平面図である。It is an upper top view of a solid fuel-fired hot water boiler. 固形燃料焚き温水ボイラの立断面図である。It is an elevation sectional view of a solid fuel-fired hot water boiler.

符号の説明Explanation of symbols

１ 燃焼室
２ 2重円筒煙管
３ 燃焼灰分離室（灰溜り室）
４ 煙管
５ 中央水柱管
６ 熱交換内筒
７ 熱交換外筒
８ 水管
９ ロストル
１０ 燃焼空気室
１１ 燃焼室点検口
１２ 灰掻き出し口
１３ 温水戻り口
１４ 温水出口
１５ 燃焼空気入口
１６ 固形燃料投入口
１７ 熱交繋ぎ管
１８ 温水分配口
１９ ヘッダー
２０ 煙室
２１ 煙出口
1 Combustion chamber 2 Double cylindrical smoke tube 3 Combustion ash separation chamber (ash chamber)
4 Smoke pipe 5 Central water column pipe 6 Heat exchange inner cylinder 7 Heat exchange outer cylinder 8 Water pipe 9 Rooster 10 Combustion air chamber 11 Combustion chamber inspection port 12 Ash scraping port 13 Hot water return port 14 Hot water outlet 15 Combustion air inlet 16 Solid fuel input port 17 Heat exchanger pipe 18 Hot water distribution port 19 Header 20 Smoke chamber 21 Smoke outlet

Claims (2)

固形燃料を燃焼する燃焼室（１）を装置の中心にもつ温水・温風・蒸気発生器の燃焼装置において、燃焼室のすぐ下流で燃焼室と同軸の２重円筒煙管内（２）で、火炉から流れる燃焼ガスが同伴する未燃固形分や灰分を分離し、この煙管下部に設けられた部屋（３）で回収し、未燃固形分野や灰分が除去された燃焼排ガスが下流の煙管をながれ、これら煙管の汚れを抑制する構造を持つことを特徴とする燃焼装置。   In a hot water / hot air / steam generator combustion device having a combustion chamber (1) for burning solid fuel at the center of the device, in a double cylindrical smoke pipe (2) coaxial with the combustion chamber immediately downstream of the combustion chamber, The unburned solids and ash accompanying the combustion gas flowing from the furnace are separated and recovered in the room (3) provided at the lower part of the smoke pipe. A combustion apparatus characterized by having a structure that suppresses contamination of these smoke pipes. 未燃固形分や灰分の分離を目的とした鉛直に立つ煙管や未燃固形分や灰分を回収するための部屋の回りを水で囲み熱回収を増加する構造を持つことを特徴とする請求項１記載の燃焼装置
A vertical smoke pipe for separation of unburned solids and ash and a structure surrounding the room for collecting unburned solids and ash with water to increase heat recovery. 1 Combustion device

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