1363166 九、發明說明： I：發明所屬之技術領域3 發明領域 本發明係有關於一種可調整使用低發熱量燃料之工業 5 爐用燃燒器的火焰長度之燃燒方法及高速噴流型擴散燃燒 式燃燒器。 【先前技術3 發明背景 以往作為用以達成NOx之抑制與爐内溫度分部之均一 !〇 化之技術，舉例言之，如第8圖所示，於專利文獻1中揭示 有一種低NOx之燃燒方法，該低NOx之燃燒方法係於爐壁 40上設置由具有燃料供給管42#燃燒用空氣流路43,之燃燒 器部51及收納有蓄熱體52a之蓄熱室52所構成的蓄熱式直 火燃燒器41，並藉由自前述燃料供給管42與燃燒用空氣供 15 給口 44將燃料46及燃燒用空氣48分別地向爐内5〇噴出而使 其緩慢燃燒》 該低NOx之燃燒方法係一種如下述之燃燒方法，即： 將燃料4 6之喷出軸4 7相對於燃燒用空氣喷出軸4 9就預定角 度α(5。至45。）向外側傾斜，並將燃料46之喷出速度設為 20 6〇m/sec以上，且使700°C以上之高溫燃燒用空氣48與燃料 46之各主流部不會相互地重疊而向爐内5〇喷出，並抑制燃 料46與燃燒用空氣48之混合，且使爐内排氣自動再循環至 燃料46與燃燒用空氣48各自之喷出流，藉此，維持緩俨之 燃燒狀態並抑制NOx。 5 1363166 然而，於前述燃燒方法中，在燃料46與燃燒用空氣48 直接混合前，藉由各自之流體之喷出運動量使爐内排氣自 動再循環，並於爐内空間進行緩慢燃燒，即，由於介於爐 内空間之燃燒氣係由未反應之燃料、有助於燃燒之以前的 5 燃燒用空氣、燃燒反應途中之中間生成物及燃燒排氣所構 成之混合氣，因此，燃燒呈現未反應之未燃氣不但會使未 圖示之吸引排氣動作中的蓄熱式直火燃燒器内部之蓄熱體 過熱，且會降低熱效率，再者，於800°C以下（燃料之自燃 溫度以下）之低爐溫時，只要沒有設置輔助燃燒器，就無法 10 繼續燃燒。 故，申請人係揭示一種高速喷流型擴散燃燒式燃燒 器，且該高速喷流型擴散燃燒式燃燒器包含有：燃燒器磚， 係以預定距離形成一次空氣流路與二次空氣流路者；風 箱，係安裝於前述燃燒器磚之後端部，且於内部具有二次 15 空氣供給管者；燃料供給管，係設置於前述風箱内，且前 端部突設於前述一次空氣流路内者；及保焰構件，係設置 於前述燃料供給管之前端部者，又，來自前述燃料供給管 之燃料喷出方向係相對於前述二次空氣流路之中心軸呈平 行或向内側傾斜（專利文獻2)。 20 此種高速喷流型擴散燃燒式.燃燒器可得到長焰，且來 自火焰之輻射強度會增加，同時可使爐内溫度分布均一化 並降低NOx產生量。1363166 IX. INSTRUCTIONS: I: TECHNICAL FIELD OF THE INVENTION FIELD OF THE INVENTION The present invention relates to a method for combusting a flame length of an industrial 5-furnace burner using a low calorific fuel and a high-speed jet-type diffusion combustion combustion Device. [Prior Art 3] In the prior art, as a technique for achieving uniformity of NOx suppression and furnace temperature division, for example, as shown in FIG. 8, a low NOx is disclosed in Patent Document 1. In the combustion method, the low-NOx combustion method is provided with a regenerative heat storage system including a burner portion 51 having a fuel supply pipe 42# combustion air flow path 43 and a regenerator 52 in which the heat storage body 52a is housed. The direct-fired burner 41, and the fuel 46 and the combustion air 48 are respectively ejected from the inside of the furnace 5 from the fuel supply pipe 42 and the combustion air supply port 44 to slowly burn the lower NOx. The combustion method is a combustion method in which the fuel injection shaft 47 of the fuel 46 is inclined outward with respect to the combustion air discharge shaft 4 by a predetermined angle α (5 to 45 Å), and the fuel is injected. The discharge speed of 46 is set to 20 6 〇m/sec or more, and the high-temperature combustion air 48 and the main flow parts of the fuel 46 of 700 ° C or more are not overlapped with each other, and are ejected into the furnace 5 , and suppressed. Mixing fuel 46 with combustion air 48 and automatically recirculating the furnace exhaust The discharge flow to each of the fuel 46 and the combustion air 48 maintains a slow combustion state and suppresses NOx. 5 1363166 However, in the foregoing combustion method, before the fuel 46 is directly mixed with the combustion air 48, the exhaust gas in the furnace is automatically recirculated by the discharge amount of the respective fluids, and the combustion is slowly performed in the furnace space, that is, Since the combustion gas in the furnace space is composed of unreacted fuel, 5 combustion airs that contribute to combustion, intermediate products in the middle of combustion reaction, and combustion exhaust gas, the combustion is presented. Unreacted unburned gas not only overheats the regenerator inside the regenerative direct-fired burner in the suction and exhaust operation (not shown), but also reduces thermal efficiency. Furthermore, it is below 800 ° C (the auto-ignition temperature of the fuel or less) At the low furnace temperature, as long as the auxiliary burner is not provided, it is impossible to continue the combustion. Therefore, the applicant discloses a high-speed jet type diffusion combustion type burner, and the high-speed jet type diffusion combustion type burner comprises: a burner brick, which forms a primary air flow path and a secondary air flow path at a predetermined distance. The bellows is installed at the rear end of the burner brick and has a secondary 15 air supply pipe inside; the fuel supply pipe is disposed in the wind box, and the front end portion protrudes from the primary air flow. And a flame-preserving member provided at a front end of the fuel supply pipe, and a fuel discharge direction from the fuel supply pipe is parallel or inward with respect to a central axis of the secondary air flow path Tilt (Patent Document 2). 20 This type of high-speed jet-type diffusion combustion type burner can obtain long flames, and the radiation intensity from the flame will increase, and the temperature distribution in the furnace can be uniformized and the amount of NOx generated can be reduced.
然而，於該高速噴流型擴散燃燒式燃燒器中，在使用 焦爐氣與高爐氣之混合氣等低發熱量燃料（500kcal/m3N 6 1363166 至4000kcal/m3N)時，為了得到必要之燃燒量，會藉由大 流量來進行喷射，因此喷流勢不易衰減，此外，低發熱量 燃料通常不易燃，因此.火焰會過度地增長，並產生爐内溫 度分布不均一之問題。 5 〔專利文獻1〕日本專利第3052262號公報 〔專利文獻2〕特開2002 —303406號公報 【發明内容】 發明之揭示 發明所欲解決之問題 10 本發明之目的係提供一種可緩和使用低發熱量燃料時 之燃料喷流之直進性，並調節火焰長度而實現最佳爐内溫度 分布的燃燒器之燃燒方法及高速喷流型擴散燃燒式燃燒器。 解決問題之手段 為了達成前述目的，本發明之燃燒器之燃燒方法係自 15 燃料供給管將燃料氣向爐内喷出，且自該燃料供給管周圍 之一次空氣流路將一次空氣向爐内喷出，並與前述燃料氣 混合而形成一次火焰，另一方面，自一次空氣流路附近之 二次空氣流路將二次空氣向爐内噴出，並與前述一次火焰 接觸而形成二次火焰者，其特徵在於：使自前述燃料供給 20 管向爐内噴出之燃料氣朝自前述一次空氣流路向爐内噴出 之一次空氣擴散。 又，本發明之高速喷流型擴散燃燒式燃燒器包含有： 一次空氣流路，係將一次空氣向爐内噴出者；二次空氣流 路，係將二次空氣向爐内喷出者；燃料供給管，係設置於 7 1363166 前述一次空氣流路内，並將燃料氣向爐内噴出者；及保焰 構件，係設置於前述燃料供給管之前端部者，又，於前述 燃料供給管之前端設置有擴散片，且該擴散片使燃料氣朝 自前述一次空氣流路向爐内喷出之一次空氣擴散。 5 前述擴散片宜具有直徑自前述燃料供給管之前端朝爐 内擴大之圓錐形狀。 或，前述擴散片宜具有覆蓋前述燃料供給管之前端之 蓋形狀，且具有使燃料氣朝一次空氣喷出之複數喷出孔。 前述擴散片宜可交換成使燃料氣朝一次空氣擴散之角 10 度不同。 發明之效果 若藉由利用前述機構所構成之本發明之燃燒方法及高 速喷流型擴散燃燒式燃燒器，則由於自燃料供給管喷出之 直進性高之燃料氣會藉由擴散片朝外側之一次空氣擴散， 15 且更與外側之二次空氣急速地混合而於燃燒器附近開始燃 燒，因此可作成短焰。 又，藉由將擴散片交換成使燃料氣朝一次空氣擴散之 角度不同者，而可依據設備作成最佳火焰長度。 t實施方式;3 20 較佳實施例之詳細說明 以下參照附圖說明本發明之實施形態，第1圖係本實施 形態之高速喷流型擴散燃燒式燃燒器10之概略構造圖，該 燃燒器10係設置於爐壁2上，且大略包含有：燃燒器磚12， 係以預定距離形成一次空氣流路（兼燃燒室）14與二次空氣 8 ⑻路16者’風箱18 ’係安裝於前述燃燒器碑12之後端部， 且於内。卩具有二次空氣供給管26者；燃料供給管28，係設 置於別述_ 18内’且前端部突設於-次空氣祕(兼燃燒 至）14内者’及複數佯焰構件30，係設置於前述燃料供給管 28之前端部者。 剛述風箱18之上部係透過調節一次空氣與二次空氣之 比例的調$閥2〇(以下稱作調整閥）與燃燒用空氣供給口 22 連通，且調整閥20係藉由控制電動機24調節開度，藉此， 控制將燃燒用空氣分配成一次空氣與二次空氣之分配比， 舉例言之，於燃料之自燃溫度（例如8〇〇<t)以下之低爐溫 時，將前述分配比調節成5〇 : 5〇，於燃料之自燃溫度以上 之爐溫時’則將前述分配比調節成20 : 80。 另，亦可自未圖示之爐内溫度調節計將開度信號送信 至前述控制電動機24而自動調節前述分配比。 自燃燒用空氣供給口 22與調整閥2〇間分歧之二次空氣 供給官2 6之前端部係與燃燒器磚丨2之二次空氣流路丨6連結。 燃料供給管28係則端部突設於燃燒器磚12之一次空氣 流路(兼燃燒室）14内，另，燃料之喷出速度係依每種燃料之 種類適當地設定，舉例言之，若為燃料之一例的LPG系燃 料氣則設定為50m/sec，若為lng系燃料氣則設定為8〇m /sec，若為COG等副產氣則設定為12〇m/sec。 在燃料供給管28位於一次空氣流路14内之前端部外周 固定有保焰構件30，保焰構件3〇係由旋轉葉片或穩定器等 所構成，且具有將自一次空氣流路14喷出之一次空氣作成 、渦流之機能。 如第2圖所示，於燃料供給管28之前端上，利用扭入設 置用以使燃料擴散之擴散片29，該擴散片29係具有自燃料 供給管28之前端朝爐内擴大之圓錐形狀，且安裝於插通燃 料供給管28内部之支持棒31的前端。擴散片29之圓錐面係 相對於燃料供給管28之中心軸構成角度0 ’另，若為於燃 料供給管28内具有中心空氣供象管者，則可將擴散片趵安 裝於該中心空氣供給管之前端以取代支持棒31，此時，必 須於擴散片29上設置中心空氣可通過之咎。又，擴散片^ 亦可利用支柱支持於燃料供給管28之前端面、内壁、—次 空氣流路14出口周圍之燃燒器磚12之内壁。 一次空氣流路14與二次空氣流路16之各中心轴14a 16a間之距離L宜為二次空氣流路16之直徑d&2 〇倍至3 〇 倍，若小於2.0倍，則由於燃料與燃燒用空氣（―次空氣及二 次空氣)在捲入燃燒器附近之爐内排氣前會急逮混合，因此 =〇x產生量會明顯地增加，反之，若大於3 ()倍，則與前述 習知技術之低N〇x之燃燒方法中的問題相同，由於爐内不 易混合燃料與燃燒m因此燃燒會變得不安^，同時 CO等未燃燒成分會增加之故。 人二軋流量宜可調節成所需 ......丨叫…沉卬芏軋流重之1/5 至V2 ’此係由於依據Ν〇χ之抑制與爐内溫度分布之均— 1 匕之觀點’在爐起動時與爐内溫度到達預;t溫度時-次空 乳與二次空氣之分配比不同之故，舉例言之，於寥c以下 (燃枓氣之自燃溫度以下)之低爐溫時，將—次空氣流量調節 1363166 成所需燃燒用空氣流量之1/2，若高於前述自燃溫度，則 將一次空氣流量調節成所需燃燒用空氣流量之1 / 5。 另，調節爐内溫度分布時，在欲提高燃燒器附近之溫 度時，舉例言之，可將前述分配比設為40 : 60而增加一次 5 空氣流量並促進燃燒器附近之燃燒，又，欲提高燃燒器遠 方之溫度時，舉例言之，可將前述分配比設為20 : 80而減 少一次空氣流量並提高二次空氣之喷出運動量，即，加快 二次空氣之流速而使燃燒氣到達遠方。 其次，說明高速喷流型擴散燃燒式燃燒器10之燃燒動 10 作，即，自低爐溫時至升溫至預定爐溫之運轉方法。 舉例言之，為燃料之一例的13A都市煤氣（以下稱作燃 料氣）係供給至燃料供給管28，且藉由設置於其前端之擴散 片29，就角度Θ朝周圍擴散、喷出。 燃燒用空氣係供給自燃燒用空氣供給口 22，且藉由調 15 整閥20將一次空氣與二次空氣之分配比調節成50: 50,即， 調節成所需燃燒用空氣流量之1/2的一次空氣係自風箱18 流入一次空氣流路14，且藉由保焰構件30構成渦流而覆蓋 自燃料供給管28喷出之燃料氣周圍並流出，同時在藉由未 圖示之引火燃燒器等點火機構著火後繼續安定燃燒，此 20 時，由於一次空氣會逐漸地受到例如以80m/sec噴出之燃 料氣引誘並自一次空氣流路14向爐内噴出，因此一次空氣 與燃料氣之接觸面中的相互擴散極少，藉此，一次燃燒構 成局部燃燒之結果，自一次空氣流路14向爐内噴出之一次 燃燒火焰内會殘留許多未燃燒部分，且於其中熱分解之碳 11 成分會提高火焰之亮度。 自一次空氣流路14喷出之一次燃燒火焰係與自二次空 氣流路16喷出之二次空氣反應而進行二次燃燒，若爐溫到 達預定溫度，例如800t，則藉由前述調整閥20將一次空氣 與一次空氣之分配此調節成20 : 80，即，一次空氣係減少 至所需燃燒用空氣流量之1/5且二次空氣之比例增加，因 此’二次空氣之喷出速度會構成100m/sec以上。又，二次 空氣係攪拌爐内環境氣體，且於一次燃燒火焰與二次空氣 分別充分地捲入爐内之排氣後相互地接觸並進行反應，其 結果，二次燃燒會變得緩慢且火焰本身之體積增加，同時 來自火焰之輻射強度增加’藉此，可形成溫度梯度及濃度 梯度小之均一化燃燒，且可使爐内溫度分布均一化並顯著 地降低NOx產生量。另，前述「濃度梯度小」係指氧、排 氣及未反應燃料以一定之分壓比介於火焰中之狀態。 又’於本實施形態之高速喷流型擴散燃燒式燃燒器1〇 中，由於在燃料供給管28之前端設置有擴散片29，因此， 自燃料供給管28喷出之直進性高之燃料氣係沿著擴散片29 之圓錐面朝外側之一次空氣擴散，且更與外側之二次空氣 急速地混合而於燃燒器附近開始燃燒，因此可作成短焰。 又，由於擴散片29係利用扭入而安裝於支持棒31，因 此’藉由將該擴散片29交換成使燃料氣朝一次空氣擴散之 角度0不同者，而可依據設備作成最佳火焰長度。 另，如第3圖所示，亦可於擴散片29之圓錐面設置相對 於母線g呈傾斜之肋部32或凹部，藉此，使沿著擴散片29喷 1363166 出之燃料氣旋繞，若依此構成，則可進一步地促、料與 一次空氣之混合並形成更短之火焰。 第4圖係顯示火焰長度相對於擴散κ 八蚁月29之圓錐面的擴 大角度0之關係，可知在擴大角度為『，即，無擴散片Μ 5之狀態下火焰長度為5m，然而，若使用具有擴:角度^為 60之圓錐面的擴散片29，則可將火焰縮短至大約一半。第 5(a)圖係顯示利用專利文獻2中所揭示之揪植。。 又燃燒窃的習知火焰However, in the high-speed jet type diffusion combustion type burner, when a low calorific fuel such as a mixture gas of coke oven gas and blast furnace gas (500 kcal/m3N 6 1363166 to 4000 kcal/m3N) is used, in order to obtain a necessary amount of combustion, The jet flow is carried out by a large flow rate, so that the jet flow potential is not easily attenuated. In addition, the low calorific fuel is generally not flammable, so the flame excessively grows and causes a problem of uneven temperature distribution in the furnace. [Patent Document 1] Japanese Patent No. 30522262 [Patent Document 2] JP-A-2002-303406 DISCLOSURE OF THE INVENTION PROBLEM TO BE SOLVED BY THE INVENTION The object of the present invention is to provide a low heat generation which can be alleviated. A combustion method of a burner and a high-speed jet type diffusion combustion type burner in which the fuel jet is straightforward, and the flame length is adjusted to achieve an optimum furnace temperature distribution. Means for Solving the Problem In order to achieve the above object, the combustion method of the burner of the present invention ejects fuel gas into the furnace from the 15 fuel supply pipe, and directs the primary air into the furnace from the primary air flow path around the fuel supply pipe. Discharging and mixing with the fuel gas to form a primary flame, and on the other hand, discharging secondary air into the furnace from a secondary air flow path near the primary air flow path, and contacting the primary flame to form a secondary flame The fuel gas discharged from the fuel supply pipe 20 into the furnace is diffused toward the primary air discharged from the primary air flow path into the furnace. Moreover, the high-speed jet type diffusion combustion type burner of the present invention includes: a primary air flow path for discharging primary air into the furnace; and a secondary air flow path for discharging secondary air into the furnace; a fuel supply pipe provided in the primary air flow path of 7 1363166 and ejecting fuel gas into the furnace; and a flame-preserving member provided at a front end of the fuel supply pipe, and further in the fuel supply pipe The front end is provided with a diffusion sheet, and the diffusion sheet diffuses the fuel gas toward the primary air ejected from the primary air flow path into the furnace. Preferably, the diffusion sheet has a conical shape having a diameter enlarged from the front end of the fuel supply tube toward the furnace. Alternatively, the diffusion sheet preferably has a lid shape covering the front end of the fuel supply tube, and has a plurality of ejection holes for discharging the fuel gas toward the primary air. Preferably, the diffusion sheets are exchanged such that the fuel gas is different from the angle of diffusion of the primary air by 10 degrees. Advantageous Effects of Invention According to the combustion method of the present invention and the high-speed jet-type diffusion combustion type burner constituted by the above mechanism, the fuel gas which is ejected from the fuel supply pipe and which is highly linear is diffused toward the outside by the diffusion sheet. Once the air is diffused, 15 and more rapidly mixes with the secondary air on the outside to start combustion near the burner, so that it can be made into a short flame. Further, by exchanging the diffusion sheets to different angles at which the fuel gas is diffused toward the primary air, the optimum flame length can be made depending on the equipment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. Fig. 1 is a schematic structural view of a high-speed jet-type diffusion combustion burner 10 of the present embodiment. The 10 series is disposed on the furnace wall 2, and roughly includes: a burner brick 12, which is formed by a predetermined distance to form a primary air flow path (and a combustion chamber) 14 and a secondary air 8 (8) road 16 is installed in the 'wind box 18' At the end of the burner monument 12, and inside. The 卩 has a secondary air supply pipe 26; the fuel supply pipe 28 is disposed in the other _ 18 and the front end portion is protruded from the second-time air (combustion) 14 and the plurality of dampers 30, It is provided at the front end of the aforementioned fuel supply pipe 28. The upper portion of the bellows 18 is communicated with the combustion air supply port 22 by adjusting the ratio of the primary air to the secondary air (hereinafter referred to as a regulating valve), and the regulating valve 20 is controlled by the motor 24 Adjusting the opening degree, thereby controlling the distribution of the combustion air into the distribution ratio of the primary air to the secondary air, for example, at a low furnace temperature below the autoignition temperature of the fuel (for example, 8 〇〇 < t) The aforementioned distribution ratio is adjusted to 5 〇: 5 〇, and at the furnace temperature above the auto-ignition temperature of the fuel, the aforementioned distribution ratio is adjusted to 20:80. Alternatively, the opening ratio signal may be sent from the furnace temperature controller (not shown) to the control motor 24 to automatically adjust the distribution ratio. The secondary air supply unit 2 6 from the combustion air supply port 22 and the regulating valve 2 is connected to the secondary air flow path 6 of the burner block 2 in the front end portion. The end portion of the fuel supply pipe 28 protrudes from the primary air flow path (and the combustion chamber) 14 of the burner brick 12. Further, the discharge speed of the fuel is appropriately set according to the type of each fuel, for example, The LPG-based fuel gas which is one example of the fuel is set to 50 m/sec, and is set to 8 〇m / sec for lng-based fuel gas, and is set to 12 〇 m/sec for by-product gas such as COG. The flame holding member 30 is fixed to the outer periphery of the end portion before the fuel supply pipe 28 is located in the primary air flow path 14. The flame holding member 3 is composed of a rotating blade or a stabilizer, and has a discharge from the primary air flow path 14. Once the air is made, the function of eddy current. As shown in Fig. 2, at the front end of the fuel supply pipe 28, a diffusion sheet 29 for diffusing fuel is provided by twisting, and the diffusion sheet 29 has a conical shape which is enlarged from the front end of the fuel supply pipe 28 toward the inside of the furnace. And installed at the front end of the support rod 31 inserted into the fuel supply pipe 28. The conical surface of the diffusion sheet 29 forms an angle with respect to the central axis of the fuel supply tube 28. Alternatively, if there is a central air supply tube in the fuel supply tube 28, the diffusion sheet can be attached to the central air supply. The front end of the tube is substituted for the support rod 31. At this time, the center air must pass through the diffusion sheet 29. Further, the diffusion sheet can be supported by the front end of the fuel supply pipe 28, the inner wall, and the inner wall of the burner tile 12 around the outlet of the secondary air flow path 14. The distance L between the primary air flow path 14 and the central axes 14a to 16a of the secondary air flow path 16 is preferably the diameter d & 2 〇 to 3 〇 times of the secondary air flow path 16, and if it is less than 2.0 times, the fuel It will be mixed with the combustion air (the secondary air and the secondary air) before being exhausted in the furnace near the burner, so the amount of 〇x generated will increase significantly, and if it is greater than 3 () times, This is the same as the problem in the low N〇x combustion method of the prior art. Since the fuel is not easily mixed in the furnace and the combustion m, the combustion becomes uncomfortable, and the unburned components such as CO increase. The flow rate of the second person should be adjusted to the required... Howl... The weight of the sinking flow is 1/5 to V2 'This is due to the suppression of the enthalpy and the temperature distribution in the furnace - 1匕 观点 ' ' At the start of the furnace and the furnace temperature reached the pre-d; t-time - the ratio of the sub-empty milk to the secondary air is different, for example, below 寥c (below the auto-ignition temperature of the flammable gas) At the low furnace temperature, the primary air flow rate is adjusted to 1363166 to 1/2 of the required combustion air flow rate. If the self-ignition temperature is higher than the aforementioned self-ignition temperature, the primary air flow rate is adjusted to 1 / 5 of the required combustion air flow rate. In addition, when adjusting the temperature distribution in the furnace, when it is desired to increase the temperature in the vicinity of the burner, for example, the aforementioned distribution ratio can be set to 40:60 to increase the air flow rate of 5 times and promote the combustion near the burner. When the temperature of the burner is increased, for example, the distribution ratio can be set to 20:80 to reduce the primary air flow rate and increase the amount of secondary air ejection movement, that is, to increase the flow rate of the secondary air to allow the combustion gas to reach. distance. Next, the combustion method of the high-speed jet type diffusion combustion type combustor 10, that is, the operation method from the low furnace temperature to the temperature rise to the predetermined furnace temperature will be described. For example, 13A city gas (hereinafter referred to as fuel gas), which is an example of fuel, is supplied to the fuel supply pipe 28, and is diffused and discharged toward the periphery by the diffusion sheet 29 provided at the tip end thereof. The combustion air is supplied from the combustion air supply port 22, and the distribution ratio of the primary air to the secondary air is adjusted to 50:50 by adjusting the valve 20, that is, adjusted to 1/ of the required combustion air flow rate. The primary air of 2 flows into the primary air flow path 14 from the wind box 18, and forms a vortex by the flame-preserving member 30, covers the periphery of the fuel gas ejected from the fuel supply pipe 28, and flows out, and is ignited by a flame not shown. After the ignition mechanism such as the burner is ignited, the combustion is continued. At this time, since the primary air is gradually attracted by the fuel gas ejected at, for example, 80 m/sec and ejected from the primary air flow path 14 into the furnace, the primary air and the fuel gas are generated. The mutual diffusion in the contact surface is extremely small, whereby the primary combustion constitutes a result of local combustion, and a plurality of unburned portions remain in the primary combustion flame ejected from the primary air flow path 14 into the furnace, and the carbon which is thermally decomposed therein is 11 The ingredients will increase the brightness of the flame. The primary combustion flame ejected from the primary air flow path 14 reacts with the secondary air ejected from the secondary air flow path 16 to perform secondary combustion. If the furnace temperature reaches a predetermined temperature, for example, 800 t, the aforementioned regulating valve is used. 20 adjust the distribution of primary air and primary air to 20: 80, that is, the primary air system is reduced to 1/5 of the required combustion air flow rate and the ratio of secondary air is increased, so the 'secondary air discharge speed Will constitute 100m / sec or more. Further, the secondary air is stirred in the atmosphere of the furnace, and after the primary combustion flame and the secondary air are sufficiently entangled in the exhaust gas in the furnace, respectively, and the reaction is performed, and the secondary combustion becomes slow and The volume of the flame itself increases, and the intensity of the radiation from the flame increases. Thereby, a uniform combustion with a small temperature gradient and a concentration gradient can be formed, and the temperature distribution in the furnace can be uniformized and the amount of NOx generated can be remarkably reduced. Further, the above "small concentration gradient" means a state in which oxygen, exhaust gas, and unreacted fuel are in a flame at a certain partial pressure ratio. Further, in the high-speed jet type diffusion combustion type burner of the present embodiment, since the diffusion piece 29 is provided at the front end of the fuel supply pipe 28, the fuel gas which is ejected from the fuel supply pipe 28 is high in straightness. The primary air is diffused along the conical surface of the diffusion sheet 29 toward the outside, and the secondary air is rapidly mixed with the outside to start combustion in the vicinity of the burner, so that a short flame can be formed. Further, since the diffusion sheet 29 is attached to the support rod 31 by twisting, "the optimum flame length can be made according to the equipment by exchanging the diffusion sheet 29 so that the angle of the fuel gas to the primary air is different from 0. . Further, as shown in Fig. 3, a rib 32 or a concave portion which is inclined with respect to the bus bar g may be provided on the conical surface of the diffusion sheet 29, whereby the fuel gas discharged along the diffusion sheet 29 1363166 may be wound. According to this configuration, it is possible to further promote mixing with the primary air and form a shorter flame. Fig. 4 is a graph showing the relationship between the flame length and the expansion angle 0 of the conical surface of the diffusion κ 八 八月29, and it can be seen that the expansion angle is ", that is, the flame length is 5 m in the state without the diffusion sheet 5, however, Using a diffuser 29 having a conical surface with an expansion angle of 60, the flame can be shortened to about half. Fig. 5(a) shows the use of the plant disclosed in Patent Document 2. . a familiar flame that burns
形狀’第5(b)圖則顯示利用本發明之火焰形狀。 第6圖係顯示其他實施形態之擴散片33，該擴散片％ 10係具有覆蓋燃料供給管28之前端的蓋形狀，且扭入燃料供 給官28之前端面，擴散片33係具有使燃料氣藉由朝一次空 氣喷出而擴散之複數噴出孔34’且各嘴出孔μ之中心軸係 相對於燃料供給管28之中心軸構成角度0。The shape '5th (b) diagram shows the shape of the flame using the present invention. Fig. 6 is a view showing a diffusion sheet 33 of another embodiment having a lid shape covering the front end of the fuel supply tube 28 and twisted into the front end surface of the fuel supply unit 28, and the diffusion sheet 33 has a fuel gas for damping The plurality of discharge holes 34' which are diffused toward the air once and the center axis of each of the nozzle holes μ form an angle of 0 with respect to the central axis of the fuel supply pipe 28.
藉由該擴散片33,自燃料供給管28噴出之直進性高之 15燃料氣亦會通過擴散片33之複數噴出孔34而朝外側之一次 空氣擴散，且更與外側之二次空氣急速地混合而於燃燒器 附近開始燃燒，因此可作成短焰。 又’由於擴散片33係利用扭入而安裝於燃燒供給管 28，因此，藉由將該擴散片33交換成使燃料氣朝一次空氣 20擴散之角度0不同者，而可依據設備作成最佳火焰長度。 另，如第7圖所示，亦可使擴散片33之各喷出孔34之中 心軸相對於法線η呈傾斜，藉此，使喷出自喷出孔34之燃料 氣方疋繞，若依此構成，則可進一步地促進燃料與一次空氣 之混合並形成更短之火焰。 13 1363166 另，本實施形態之高速喷流型擴散燃燒式燃燒器ίο係 使用調整閥20將燃燒用空氣分配供給至一次空氣與二次空 氣，然而，亦可設置分別透過流量控制閥與一次空氣流路 14及二次空氣流路16連接的一次空氣供給管與二次空氣供 5 給管，且分別調節前述各流量控制閥，藉此，設定一次空 氣及二次空氣之各流量。 【圖式簡單說明3 第1圖係高速喷流型擴散燃燒式燃燒器之概略構造圖。 第2圖係燃料供給管之擴散片之放大截面圖。 10 第3(a)、3(b)圖係顯示第2圖之擴散片之變形例的側視 圖（a)及後視圖（b)。 第4圖係顯示火焰長度相對於擴散片之圓錐面的擴大 角度之關係圖表。 第5(a)、5(b)圖係比較習知例與本發明之火焰形狀圖。 15 第6圖係顯示燃料供給管之擴散片之其他例的放大截 面圖。 第7圖係顯示第6圖之擴散片之變形例的正視圖。 第8圖係用以說明習知低NOx之燃燒方法例之圖。 【主要元件符號說明】 2，40...爐壁 14a，16a...中心轴 10.. .高速喷流型擴散燃燒式燃 16...二次空氣流路 燒器 18...風箱 12…燃燒器碑 20·.·調節一次空氣與二次空氣 14.. . 一次空氣流路 之比例的調整閥 14 1363166 22，44…燃燒用空氣供給口 24.. .控制電動機 26…二次空氣供給管 28，42...燃料供給管 29，33...擴散片 30.. .保焰構件 31.. .支持棒 32.. .肋部 34.. .喷出孔 41.. .蓄熱式直火燃燒器 43.. .燃燒用空氣流路 46.··燃料 47.. .噴出軸 48.. .燃燒用空氣 49.. .燃燒用空氣喷出軸 50…爐内 51…燃燒器部 52.. .蓄熱室 52a...蓄熱體 d...二次空氣流路之直徑 g...母線 L... 一次空氣流路與二次空氣 流路之各中心軸間之距離 η...法線 α，0…角度 15With the diffusion sheet 33, the fuel gas 15 which is ejected from the fuel supply pipe 28 is also diffused to the outside by the plurality of discharge holes 34 of the diffusion sheet 33, and the secondary air to the outside is rapidly increased. The mixture starts to burn near the burner, so it can be made into a short flame. Further, since the diffusion sheet 33 is attached to the combustion supply tube 28 by twisting, the diffusion sheet 33 is exchanged so that the angle of the fuel gas to the primary air 20 is different from 0, and the optimum can be made according to the device. Flame length. Further, as shown in Fig. 7, the central axis of each of the discharge holes 34 of the diffusion sheet 33 may be inclined with respect to the normal line η, whereby the fuel gas discharged from the discharge hole 34 may be entangled. According to this configuration, the mixing of the fuel and the primary air can be further promoted to form a shorter flame. 13 1363166 In addition, the high-speed jet type diffusion combustion type burner of the present embodiment is configured to supply the combustion air to the primary air and the secondary air by using the adjustment valve 20, however, it is also possible to separately provide the flow rate control valve and the primary air. The primary air supply pipe and the secondary air connected to the flow path 14 and the secondary air flow path 16 are supplied to the five supply pipes, and the respective flow rate control valves are adjusted, thereby setting the respective flow rates of the primary air and the secondary air. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic structural view of a high-speed jet type diffusion combustion type burner. Fig. 2 is an enlarged cross-sectional view showing a diffusion sheet of a fuel supply pipe. 10 (a) and 3 (b) are side views (a) and rear views (b) showing a modification of the diffusion sheet of Fig. 2. Figure 4 is a graph showing the relationship between the length of the flame and the angle of expansion of the conical surface of the diffuser. Figures 5(a) and 5(b) show a comparison of the flame shape of the conventional example and the present invention. 15 Fig. 6 is an enlarged cross-sectional view showing another example of the diffusion sheet of the fuel supply tube. Fig. 7 is a front elevational view showing a modification of the diffusion sheet of Fig. 6. Fig. 8 is a view for explaining an example of a conventional low NOx combustion method. [Main component symbol description] 2, 40... furnace wall 14a, 16a... central axis 10.. high-speed jet type diffusion combustion type combustion 16... secondary air flow path burner 18... wind Box 12... burner monument 20···Adjust primary air and secondary air 14.. Adjusting valve for the ratio of primary air flow path 14 1363166 22,44...combustion air supply port 24....control motor 26...two Secondary air supply pipes 28, 42... fuel supply pipes 29, 33... diffuser 30.. flame-proof member 31.. support bar 32.. rib 34... vent hole 41.. . Regenerative direct fire burner 43.. Combustion air flow path 46.·· Fuel 47.. Discharge shaft 48.. Combustion air 49.. Combustion air ejecting shaft 50...In-furnace 51... Burner portion 52.. regenerator 52a... regenerator d... diameter of secondary air flow path g... bus bar L... between the central axes of the primary air flow path and the secondary air flow path Distance η...normal α, 0... angle 15