電廠低氮燃燒器與脫銷技術

隨著我國環保標準的進一步提高，不能滿足國家環保標準排放的火力發電機組相繼進行了低氮或脫硝改造。機組在進行低氮燃燒器和脫硝系統改造后，在實際運行中NOx的排放量均能滿足2011版《火力發電廠污染物排放標準》要求，脫硝系統運行基本正常。
With the further improvement of China's environmental protection standards, coal-fired power units that cannot meet the national environmental protection standards have successively carried out low-nitrogen or denitrification transformation. In low nitrogen burner and denitration system after modification, in the actual operation of NOx emissions can meet the 2011 edition "coal-fired power plant emissions standard" requirement, denitration system running normally.

1、低氮燃燒及脫硝技術
1. Low-nitrogen combustion and denitrification technology

低氮燃燒機組主要是針對NOx的兩種主要生成機理，在降低燃燒溫度的同時，降低著火區域的氧氣濃度。以抑制爐氮氧化物的生成。通過采用爐內低NOx燃燒技術，能將NOx排放濃度降低30%～60%。目前普遍采用的低氮燃燒技術主要是通過低氮燃燒器改造，來實現爐內低氧、分級配分的燃燒特性，降低NOx的減排。
The low nitrogen combustion unit is mainly aimed at two main generating mechanisms of NOx, which reduce the oxygen concentration in the ignition area while reducing the combustion temperature. To inhibit the formation of furnace nitrogen oxides. By using the low NOx combustion technology in the furnace, the NOx emission concentration can be reduced by 30% ~ 60%. Currently, the commonly used low-nitrogen combustion technology is mainly through the transformation of low-nitrogen burner to realize the combustion characteristics of low-oxygen and graded blending in the furnace and reduce the emission reduction of NOx.

由于爐內低氮燃燒技術的局限性,使得NOx的排放不能很好的滿足環保要求，為進一步降低NOx的排放，必須對燃燒后的煙氣進行脫硝處理。目前通行的煙氣脫硝工藝大致可分為干法、半干法和濕法3類。其中干法SCR脫硝工藝以其脫硝裝置結構簡單、運行方便、可靠性高、脫硝效率高、一次投資相對較低等諸多優點，在我國得到了廣泛的商業應用。
Due to the limitation of the low-nitrogen combustion technology in the furnace, the emission of NOx cannot meet the requirements of environmental protection. In order to further reduce the emission of NOx, it is necessary to denitrify the smoke after combustion. The current flue gas denitrification process can be divided into dry, semi-dry and wet processes. Including dry SCR denitration technology with its denitration device has simple structure, convenient operation and high reliability, high denitration efficiency, a lot of advantages, an investment is relatively low in our country has been widely commercial application.

SCR脫硝反應器按照相對于除塵器的安裝位置，可分為高含塵和低含塵兩類。但由于低含塵需要安裝蒸汽加熱器和煙氣換熱器(GGH)，系統復雜，投資大，故一般選擇高含塵工藝。SCR裝置主要由脫硝反應劑制備系統和反應器本體組成。
The SCR denitrification reactor can be divided into high dust content and low dust content according to the installation position of relative dust collector. However, because the low dust content requires the installation of steam heater and gas heat exchanger (GGH), the system is complex and the investment is large, so the high dust content technology is generally chosen. The SCR device is mainly composed of the preparation system of denitrification reaction agent and the reactor body.

通過向反應器內噴入脫硝反應劑NH3，將NOx還原為氮氣和水蒸氣。制氨一般有尿素、液氨、氨水等3種方法。目前主要采用尿素和液氨兩種制氨方法。脫硝催化劑其材料一般以TiO2為載體，并摻入V2O5和WO3等活性成分。催化劑的活性溫度范圍從300℃～420℃[3]不等。催化劑有蜂窩式和板式兩種。
The NOx was reduced to nitrogen and water vapor by spraying the denitrification reagent NH3 into the reactor. Ammonia production generally has urea, liquid ammonia, ammonia water and other three methods. At present, urea and liquid ammonia are mainly used to make ammonia. The denitrification catalyst is usually supported by TiO2 and mixed with V2O5 and WO3. The activity of the catalyst temperature range from 300 ℃ to 420 ℃ range [3]. There are two kinds of catalyst, honeycomb and plate.

機組之前未采用低氮燃燒方式，且無脫硝裝置。此類機組在氮氧化物減排改造中，改造幅度大，低氮燃燒器改造以及加裝脫硝裝置。上述幾種進行脫硝改造的機組，同時進行了空預器、除塵器以及引風機的改造。

No low nitrogen combustion method and no denitrification device have been used before. In the modification of nitrogen oxide reduction, the modification range is large, the modification of low nitrogen burner and the addition of denitrification device. The above mentioned denitrification units have been modified with air preheater, dust collector and fan.