JPS6362645B2 - - Google Patents
Info
- Publication number
- JPS6362645B2 JPS6362645B2 JP54142120A JP14212079A JPS6362645B2 JP S6362645 B2 JPS6362645 B2 JP S6362645B2 JP 54142120 A JP54142120 A JP 54142120A JP 14212079 A JP14212079 A JP 14212079A JP S6362645 B2 JPS6362645 B2 JP S6362645B2
- Authority
- JP
- Japan
- Prior art keywords
- air
- combustion
- fuel
- burner
- supplied
- 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.)
- Expired
Links
- 238000002485 combustion reaction Methods 0.000 claims description 23
- 239000000446 fuel Substances 0.000 claims description 23
- 239000007789 gas Substances 0.000 claims description 13
- MWUXSHHQAYIFBG-UHFFFAOYSA-N nitrogen oxide Inorganic materials O=[N] MWUXSHHQAYIFBG-UHFFFAOYSA-N 0.000 claims description 9
- 238000009841 combustion method Methods 0.000 claims description 8
- 239000000567 combustion gas Substances 0.000 claims 2
- 238000006722 reduction reaction Methods 0.000 description 7
- 238000006243 chemical reaction Methods 0.000 description 5
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 4
- 230000000694 effects Effects 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 3
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 description 2
- 238000000354 decomposition reaction Methods 0.000 description 2
- 239000013067 intermediate product Substances 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 229910052757 nitrogen Inorganic materials 0.000 description 2
- 238000007254 oxidation reaction Methods 0.000 description 2
- 238000011144 upstream manufacturing Methods 0.000 description 2
- 239000004215 Carbon black (E152) Substances 0.000 description 1
- 229910021529 ammonia Inorganic materials 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 238000010531 catalytic reduction reaction Methods 0.000 description 1
- 230000002860 competitive effect Effects 0.000 description 1
- 239000000428 dust Substances 0.000 description 1
- 239000002803 fossil fuel Substances 0.000 description 1
- 229930195733 hydrocarbon Natural products 0.000 description 1
- 150000002430 hydrocarbons Chemical class 0.000 description 1
- 238000002347 injection Methods 0.000 description 1
- 239000007924 injection Substances 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 230000002265 prevention Effects 0.000 description 1
- 229940018489 pronto Drugs 0.000 description 1
- 238000005979 thermal decomposition reaction Methods 0.000 description 1
Description
【発明の詳細な説明】
本発明は、排ガス中の窒素酸化物を低減するに
好適な燃焼方法に関するものである。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a combustion method suitable for reducing nitrogen oxides in exhaust gas.
従来、公害防止の問題から化石燃料燃焼ボイラ
における生成窒素酸化物（以下NOxと称す。）の
低減法として次の手段が施されて来た。 Conventionally, the following methods have been used to reduce nitrogen oxides (hereinafter referred to as NOx) generated in fossil fuel combustion boilers due to the problem of pollution prevention.
(1) 排ガス混合
(2) 多段燃焼
(3) 火炎の分割
(4) 燃料変換
(5) 触媒による還元
(6) ハイドロカーボン、アンモニア注入による気
相還元
しかし、(1)と(3)によつてNOxを低減させよう
とすると幣害としてCO、ダスト量が増加する傾
向にあり、(2)・(5)〜(6)の方法によると装置が大き
くなりコスト的に不利となる。したがつて理想的
な、NOx低減策としては燃料中に窒素分の少な
いものを使用する(4)がよい。(1) Exhaust gas mixing (2) Multistage combustion (3) Flame splitting (4) Fuel conversion (5) Catalytic reduction (6) Gas phase reduction by hydrocarbon and ammonia injection However, (1) and (3) If an attempt is made to reduce NOx, the amount of CO and dust tends to increase as a negative effect, and methods (2) and (5) to (6) require larger equipment, which is disadvantageous in terms of cost. Therefore, the ideal NOx reduction measure is to use fuel with a low nitrogen content (4).
このようにして燃料中に窒素分のないもしくは
少ない燃料にしただけではまだ充分でなく、実際
には(1)〜(4)による燃焼改善が併用して実施されて
いる。 It is not enough to simply make the fuel free or low in nitrogen content in this way, and in fact, combustion improvements based on (1) to (4) are also being implemented in combination.
従つて、社会的NOx規制の要求がさらに高く
なつた場合にも、(5)、(6)などの必要なしに燃焼改
善だけですませることができればそれが最も望ま
しい低NOx燃焼の手段である。 Therefore, even if the social demands for NOx regulations become even higher, if it is possible to improve combustion without the need for (5) and (6), it is the most desirable means of low NOx combustion.
このため発明者等はさきに第１図に示すような
燃焼方法を実験の結果に基き提案した。即ち排ガ
ス流れについて、上流（図面においては下段）に
主バーナ２を炉壁１に設け、その下流たる中流
（図面においては中段）に副バーナを設け、さら
にその下流（図面においては上段）に空気供給口
４を設け、夫々の空気箱５A，５B，５Cには管路
６A，６B，６Cより燃焼用の空気を供給する。こ
の場合において夫々の管路に設けたダンパ７A，
７B，７Cにより供給する空気量、即ち二次空気量
を制御する。 For this reason, the inventors previously proposed a combustion method as shown in FIG. 1 based on the results of experiments. In other words, regarding the exhaust gas flow, the main burner 2 is installed on the furnace wall 1 upstream (lower stage in the drawing), the sub-burner is installed in the downstream middle stream (middle stage in the drawing), and further downstream (upper stage in the drawing) is the main burner 2. A supply port 4 is provided, and combustion air is supplied to each air box 5A , 5B , 5C from a pipe 6A , 6B , 6C . In this case, the dampers 7 A ,
7 B and 7 C control the amount of air to be supplied, that is, the amount of secondary air.
主バーナ２による燃焼域Ａは空燃比１以下の燃
料過剰燃焼域とし、副バーナ３はさらに空燃比の
低いものにし気相還元域となる燃焼域Ｂを形成さ
せ、空気供給口４から十分な空気量を供給して残
留未燃分を完全燃焼させる燃焼域Ｃを形成するも
のである。これにより排ガス中のNOxはいちぢ
るしく低いものとなることが確められた。 The combustion area A of the main burner 2 is an excess fuel combustion area with an air-fuel ratio of 1 or less, and the auxiliary burner 3 has an even lower air-fuel ratio to form a combustion area B that is a gas phase reduction area. A combustion zone C is formed in which the amount of air is supplied to completely burn the remaining unburned matter. This confirmed that NOx in the exhaust gas was significantly lower.
このNOx低減の機構を考察すると、燃料過剰
燃焼域Ａにおいては、生成NOxとしてサーマル
NOx（Thermal NOx）のみならず炭化水素燃料
過剰域でのみでてくるプロンプトNOx（Prompt
NOx）、を生ずる。これらの生成反応は次式に代
表される。（枠で囲んだものは中間生成物のラジ
カルであることを示す）
O2→２・Ｏ (1)
N2＋・Ｏ→・Ｎ＋NO (2)
・Ｎ＋O2→・Ｏ＋NO (3)
H2O→・Ｈ＋・OH (4)
・Ｎ＋・OH→・Ｈ＋NO (5)
CH4→・CH3＋・Ｈ (6)
N2＋・CH3→・NH2＋HCN (7)
・Ｈ＋HCN→・CN＋H2 (8)
・CN＋O2→CO＋NO (9)
・NH2＋O2→H2O＋NO (10)
ここで式(1)〜(5)はサーマルNOx、(6)〜(10)はプ
ロンプトNOxの生成について示している。 Considering the mechanism of this NOx reduction, in the fuel excess combustion region A, thermal energy is generated as generated NOx.
Not only NOx (Thermal NOx) but also prompt NOx (Prompt
NOx). These production reactions are represented by the following formula. (Those enclosed in a frame indicate radicals of intermediate products.) O 2 →2・O (1) N 2 +・O→・N+NO (2) ・N+O 2 →・O+NO (3) H 2 O →・H+・OH (4) ・N+・OH→・H+NO (5) CH 4 →・CH 3 +・H (6) N 2 +・CH 3 →・NH 2 +HCN (7) ・H+HCN→・CN+H 2 (8) ・CN+O 2 →CO+NO (9) ・NH 2 +O 2 →H 2 O+NO (10) Here, equations (1) to (5) are for thermal NOx generation, and (6) to (10) are for prompt NOx generation. It shows.
本発明者等は、これらの生成反応および分解反
応を種々検討したところCOガスのごとき還元性
ガスではO2により妨害されほとんどその効力を
発揮できず、燃焼火炎内に生成するラジカルに代
表される中間生成物が還元能力を有しているもの
であることがわかつた。 The present inventors have investigated various production and decomposition reactions of these, and found that reducing gases such as CO gas are hindered by O 2 and can hardly exhibit their effectiveness, and are typified by radicals generated within combustion flames. It was found that the intermediate product has reducing ability.
また副バーナの部分酸化、熱分解反応としては
CH4→・CH3＋・Ｈ (11)
N2＋CH3→・NH2＋HCN (12)
・Ｈ＋HCN→・CN＋H2 （13）
気相還元として
NO＋・NH2→N2＋H2O （14）
NO＋・CN→N2＋CO （15）
NO＋CO→N2＋O2 （16）
特に注目されるのは（14）、（15）式による分解
であつて、(9)、(10)式のプロントNOxの生成反応
と比較して明らかなごとく・NH2、・CN等のラ
ジカルと反応するNOおよびO2の競合反応となる
点にある。 Also, partial oxidation and thermal decomposition reactions in the secondary burner include CH 4 →・CH 3 +・H (11) N 2 +CH 3 →・NH 2 +HCN (12) ・H+HCN→・CN+H 2 (13) NO+ as gas phase reduction・NH 2 →N 2 +H 2 O (14) NO+・CN→N 2 +CO (15) NO+CO→N 2 +O 2 (16) Particular attention is paid to the decomposition using equations (14) and (15). As is clear from the comparison with the pronto NOx production reactions of formulas , (9) and (10), this is a competitive reaction between NO and O 2 reacting with radicals such as .NH 2 and .CN.
この発明はこのような低NOx燃焼方法をさら
に改善する燃焼方法を提案することを目的とす
る。 The purpose of this invention is to propose a combustion method that further improves such a low NOx combustion method.
要するにこの発明はバーナを３段に配置し排ガ
ス流れについて上流に主バーナで燃料過剰域を、
中流に副バーナで気相還元域を、下流にアフタバ
ーナで完全燃焼域を形成させることを特徴とする
低NOx燃焼方法である。 In short, this invention arranges the burners in three stages, and uses the main burner upstream of the exhaust gas flow to eliminate the excess fuel area.
This low NOx combustion method is characterized by forming a gas-phase reduction zone in the midstream with an auxiliary burner and a complete combustion zone in the downstream with an afterburner.
さきに説明した燃焼域Ａ，Ｂ，ＣによるNOx
低減燃焼の実験をし、採取ガス分析等を行なつた
結果では空気供給口４から過剰な空気を供給して
未燃成分を完全燃焼させようとしてもこの空気供
給のみでは燃焼たる酸化反応が充分に行なはれな
いことが確められた。これは供給空気が予熱して
あつても第１図の燃焼域Ｃにおいて温度降下あり
反応即ち残留未燃分の焼却が充分に行なわれない
ことによるものと推定される。 NOx due to combustion zones A, B, and C explained earlier
As a result of experiments on reduced combustion and analysis of sampled gas, it was found that even if an attempt was made to completely burn the unburned components by supplying excess air from the air supply port 4, this air supply alone would not be enough to carry out the oxidation reaction, which is combustion. It was confirmed that this could not be done. This is presumed to be due to the fact that even if the supplied air is preheated, there is a temperature drop in the combustion zone C of FIG. 1, and the reaction, ie, the incineration of residual unburned matter, is not carried out sufficiently.
そのためこの発明においては空気供給口４の部
分にアフタバーナを設けることとしたものであ
る。第２図はこの発明にかかる装置を示す燃焼装
置部分の縦断面図を示すものである。主バーナ２
の上方に副バーナ３を位置させ、そのさらに上方
にアフタバーナ８を位置させるものである。 Therefore, in this invention, an afterburner is provided at the air supply port 4. FIG. 2 shows a longitudinal sectional view of a combustion device portion showing an apparatus according to the present invention. Main burner 2
The auxiliary burner 3 is located above the auxiliary burner 3, and the afterburner 8 is located further above the auxiliary burner 3.
この場合主バーナ２の空燃比は0.4乃至0.9好ま
しくは約0.6、副バーナ３の空燃比を0.2乃至0.8好
ましくは約0.4、アフタバーナ８の空燃比は１以
上好ましくは1.3として燃焼させることがNOx低
減効果が大であつた。燃焼用空気の供給は風箱５
Ａ，５B，５Cに接続する空気供給の管路６A，６B，
６Cに設けたダンパ７A，７B，７Cにより行なうこ
とができる。更に詳しくはバーナを中心とする筒
状体２A，３Aの空気供給口を覆いかつその開口面
積を調節するスライドダンパ９A，９Bによりする
ことができる。 In this case, the air-fuel ratio of the main burner 2 is 0.4 to 0.9, preferably about 0.6, the air-fuel ratio of the auxiliary burner 3 is 0.2 to 0.8, preferably about 0.4, and the air-fuel ratio of the afterburner 8 is 1 or more, preferably 1.3 to reduce NOx. The effect was great. Combustion air is supplied by wind box 5
Air supply pipes 6 A , 6 B , connected to A , 5 B , 5 C
This can be done using dampers 7 A , 7 B , and 7 C provided at 6 C. More specifically, this can be achieved by slide dampers 9 A and 9 B that cover the air supply ports of the cylindrical bodies 2 A and 3 A centering around the burner and adjust their opening areas.
また各バーナに供給する燃料の供給量の比率は
主バーナ２については全供給燃料量の約65％、副
バーナ３については約30％、アフタバーナ８につ
いては約５％とするのが気相還元によるNOx低
減よりして効果の大なる条件である。 In addition, the ratio of the amount of fuel supplied to each burner is approximately 65% of the total amount of fuel supplied to main burner 2, approximately 30% to auxiliary burner 3, and approximately 5% to afterburner 8. This is a condition that is more effective than NOx reduction.
この発明は、従来の空気供給口につき、アフタ
バーナを設けるだけでよいことからその実施は極
めて容易である。またこの発明は広く一般用工業
炉、ガスタービン等にも適用でき、いちぢるしく
NOxを低減するという効果を奏するものである。 This invention is extremely easy to implement since it is only necessary to provide an afterburner for a conventional air supply port. Furthermore, this invention can be widely applied to general industrial furnaces, gas turbines, etc., making it particularly useful.
This has the effect of reducing NOx.
第１図は空気供給口を有する低NOx燃焼装置
の縦断面図、第２図はこの発明の実施にかかる装
置の縦断面図である。
１……炉壁、２……主バーナ、３……副バー
ナ、５A，５B，５C……風箱、６A，６B，６C……
空気を供給する管路、７A，７B，７C……ダンパ、
８……アフタバーナ、９A，９B……スライドダン
パ、Ａ，Ｂ，Ｃ、……燃焼域。
FIG. 1 is a longitudinal sectional view of a low NOx combustion device having an air supply port, and FIG. 2 is a longitudinal sectional view of the device according to the present invention. 1... Furnace wall, 2... Main burner, 3... Sub-burner, 5 A , 5 B , 5 C ... Wind box, 6 A , 6 B , 6 C ...
Pipe lines for supplying air, 7 A , 7 B , 7 C ... dampers,
8... Afterburner, 9 A , 9 B ... Slide damper, A, B, C,... Combustion area.
Claims (1)
ガス中の窒素酸化物を、燃料を空気と共に炉内に
供給ししかも前記主バーナの空燃比よりも低い空
燃比の副バーナの燃焼ガスで気相還元し残余未燃
分をアフタバーナを備えた空気供給口から供給す
る空気により完全燃焼させることを特徴とする低
NOx燃焼方法。 ２ 主バーナの空燃比を0.4乃至0.9好ましくは約
0.6、副バーナの空燃比を0.2乃至0.8好ましくは約
0.4、アフタバーナの空燃比を１以上好ましくは
1.3として燃焼させることを特徴とする特許請求
の範囲第１項記載の低NOx燃焼方法。 ３ 主バーナへの燃料供給量を燃焼させる全供給
燃料量の約65％、副バーナへの燃料供給量を約30
％、アフタバーナへの燃料供給量を約５％とする
ことを特徴とする特許請求の範囲第１項又は第２
項記載の低NOx燃焼方法。[Scope of Claims] 1. Nitrogen oxides in the combustion gas of a main burner that is combusted at an air-fuel ratio of 1 or less are supplied to the furnace together with fuel and air-fuel ratio is lower than that of the main burner. It is characterized by reducing the gas phase with the combustion gas of the burner and completely combusting the remaining unburned matter with the air supplied from the air supply port equipped with an afterburner.
NOx combustion method. 2 Adjust the air-fuel ratio of the main burner to 0.4 to 0.9, preferably about
0.6, the air-fuel ratio of the auxiliary burner to 0.2 to 0.8, preferably about
0.4, afterburner air-fuel ratio preferably 1 or more
1.3. The low NOx combustion method according to claim 1, characterized in that the combustion is performed as 1.3. 3 The amount of fuel supplied to the main burner is approximately 65% of the total amount of fuel supplied for combustion, and the amount of fuel supplied to the auxiliary burner is approximately 30%.
%, and the amount of fuel supplied to the afterburner is approximately 5%.
Low NOx combustion method described in section.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP14212079A JPS5666608A (en) | 1979-11-05 | 1979-11-05 | Combustion method with low nox |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP14212079A JPS5666608A (en) | 1979-11-05 | 1979-11-05 | Combustion method with low nox |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS5666608A JPS5666608A (en) | 1981-06-05 |
| JPS6362645B2 true JPS6362645B2 (en) | 1988-12-05 |
Family
ID=15307859
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP14212079A Granted JPS5666608A (en) | 1979-11-05 | 1979-11-05 | Combustion method with low nox |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS5666608A (en) |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS51106240A (en) * | 1975-03-14 | 1976-09-21 | Onoda Cement Co Ltd | Nenshohaigasuchuno nox oteigensuruhoho oyobi sochi |
| JPS54105328A (en) * | 1978-02-06 | 1979-08-18 | Toyo Tire & Rubber Co Ltd | Method and device for burning ultra-low nox in fuels containing organic nitrogen |
-
1979
- 1979-11-05 JP JP14212079A patent/JPS5666608A/en active Granted
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS51106240A (en) * | 1975-03-14 | 1976-09-21 | Onoda Cement Co Ltd | Nenshohaigasuchuno nox oteigensuruhoho oyobi sochi |
| JPS54105328A (en) * | 1978-02-06 | 1979-08-18 | Toyo Tire & Rubber Co Ltd | Method and device for burning ultra-low nox in fuels containing organic nitrogen |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS5666608A (en) | 1981-06-05 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JPS6225927B2 (en) | ||
| RU2299758C2 (en) | Device and the method of control over nitrogen dioxide ejections from the boilers burning the carbonic fuels without usage of the external reactant | |
| JP2942711B2 (en) | Deep stage combustion method | |
| JPH05340505A (en) | Method for reducing amount of production of nitrogen oxide produced during combustion | |
| EP0521949B1 (en) | IMPROVED LOW NOx COGENERATION PROCESS AND SYSTEM | |
| US5178101A (en) | Low NOx combustion process and system | |
| NL8001071A (en) | METHOD FOR REDUCING NO EMISSIONS | |
| JPS6115962B2 (en) | ||
| WO2005079305A2 (en) | Method for in-furnace regulation of so3 in catalytic systems | |
| US5041268A (en) | Reactor for reducing the contents of nitrogen oxides and sulphur oxides in combustion gases | |
| US5934892A (en) | Process and apparatus for emissions reduction using partial oxidation of combustible material | |
| EP2065570B1 (en) | Burner for generating reductive atmosphere of exhaust gas in engine cogeneration plant having denitrification process | |
| JPH026961B2 (en) | ||
| JPS6362645B2 (en) | ||
| Straitz III et al. | Combat NOx with better burner design | |
| JPS60126508A (en) | Finely powdered coal burning device | |
| JPS6249521B2 (en) | ||
| JPH0128283B2 (en) | ||
| KR840000354B1 (en) | Combustion method for low nox | |
| JPH09126412A (en) | Low nox boiler | |
| JPS6026923B2 (en) | Low NOx combustion equipment | |
| JP2667607B2 (en) | Structure of low NOx boiler | |
| US8251694B2 (en) | Method for in-furnace reduction flue gas acidity | |
| RU2293254C2 (en) | Method of removing toxic agents from combustion products of gas fuel | |
| SU1749618A1 (en) | Method of gas fuel combustion |