火电行业(中-英)

每台机组相应的配两个脱硝反应塔。为保证反应塔内有良好的反应环境和充分反应时间,在反应塔入口装设有性能可靠的烟气整流装置,同时保证烟气流速在5m/s左右。在反应塔中布置有三层催化剂安装位置,其中2层运行,1层备用,采用板式或蜂窝式催化剂,同时配备必要的吹灰装置。反应塔的尺寸大小根据锅炉100%BMCR工况下烟气流量、流速及催化剂的性能模块尺寸综合考虑后确定。本工程单个SCR反应塔截面形状为矩形,截面尺寸为12x15m,每台锅炉两个反应塔。

Two denitration reactors are provided for each unit. To ensure a favorable reaction environment and adequate reaction time in the reactor, a flue gas rectification device of reliable performance is provided at the inlet of the reactor, and the flue gas velocity is kept at about 5 m/s. Three catalyst layers are provided in the reactor, of which two layers are for normal operation and one layer is for standby. A plate or honeycomb catalyst is adopted with necessary soot blowing device provided. The dimensions of the reactor are determined based on the flue gas flow & velocity under 100% BMCR operating conditions as well as the performance and module dimension of the catalyst. In this project, the section of a single SCR reactor is rectangular, with a sectional dimension of 12 × 15 m. Two reactors are provided for each boiler.

烟气流经反应塔时,NOXNH3在催化剂的作用下发生还原反应生成N2H2O,但催化剂在反应中并不被消耗,只是随着运行时间的加长,催化剂活性下降,当脱硝率和氨逃逸率不能满足要求时,再增加备用的催化剂层或更换新催化剂层。

While flue gas passes through the reactor, NOx and NH3 react to produce N2 and H2O under the effect of the catalyst. The catalyst, however, is not consumed during the reduction reaction. But with the operation continuing on, the catalyst activation declines. When NOx removal efficiency and ammonia slip cannot meet the requirement, the standby catalyst layer shall be put into service or a new catalyst layer shall be applied. 

烟道中烟气的流动速度场、温度场和反应物浓度(NH3/NOX摩尔比)分布越均匀,脱硝反应的效率越有保障。我公司可利用先进的计算机流体分析方法,对烟气的流动场、温度场和浓度场进行数值计算,模拟出实际情况,使脱硝反应塔性能最佳。我公司在该领域(除尘器气流分布试验设计)已经积累了丰富的实践经验,具有丰富的设计经验和性能保证能力。为获得可靠的性能,依据经验,SCR反应塔顶部入口截面上的烟气速度分布最大偏差小于10%15%,烟气温度分布最大偏差小于1015℃NH3/NOx摩尔比分布最大偏差小于5%10%

The more uniformly the flue gas flow velocity field, temperature field and reactant concentration (NH3/NOx molar ratio) are distributed in the flue, the more guaranteed the NOx removal reaction efficiency is. Our company makes numerical calculations on the flow field, temperature field and concentration field of the flue gas by using an advanced computer fluid analysis method and simulates the actual situation to optimize the denitration reactor’s performance. Our company has accumulated rich practical experience in the experimental design of airflow distribution in the dust precipitator,has got rich design experience and can guarantee outstanding performance. To obtain reliable performance, in light of experience, the maximum deviation of flue gas velocity distribution on the section at the inlet on the top of the reactor should be under 10%~15%, the maximum deviation of flue gas temperature distribution under 10~15°C, and the maximum deviation of NH3/NOx molar ratio distribution under 5%~10%.

反应塔设计成烟气竖直向下流动,反应塔入口及出口段设导流板,设膨胀节吸收三维膨胀。

The reactor is designed to have the flue gas flow downwards vertically. A splitter is provided at the inlet and outlet section of the reactor, and an expansion joint is provided to absorb three-dimension expansion.

反应塔设置足够大小和数量的人孔门,含催化剂更换的检修门。

Manhole doors of adequate size and number are provided for the reactor, including an access door for the replacement of the catalyst.

反应塔附近设置足够大的催化剂及吹灰器维修及更换平台,并配备必要的催化剂起吊、安装、更换用单轨和电动葫芦。

An access platform of adequate size is provided for maintenance and replacement of the catalyst and the soot blower near the reactor, along with the monorail and motor hoist required for lifting, erection and replacement of the catalyst.