Issue 37/2015 - Steam balance leads to energy savings in stationary bed gasification

Recently, the integrated energy-saving technology of secondary steam of fixed bed gasifier developed by Qingdao Xiangrui Hengtai Chemical Technology Co.
, Ltd.
has been applied
in Shaanxi Chenghua Company and Anhui Haoyuan Group.
Practical application has proved that this technology can improve the gasification efficiency of the steam system, optimize the gas composition, and realize the comprehensive energy saving and consumption
reduction of raw material coal, steam and electricity consumption.

According to reports, on the basis of the existing steam process, through the transformation of the steam system, the gas generation of Anhui Haoyuan Group has increased by 7%~10%, the comprehensive residual carbon of ash residue has been reduced by 5%~7%, and the steam consumption has reached the lowest in the country; The CO2 content of Shaanxi Urbanization Company was significantly reduced, the effective gas content was significantly increased, the consumption of ammonia coal rods was stable at 1.
37~1.
40 tons, and the external steam supply was reduced to 1.
8 tons
.

The two-stage steam comprehensive energy-saving technology reduces the pressure operation on the basis of the existing steam main network unchanged, and increases the second-stage steam and the main
line steam.
In the gas production stage, the upblowing steam pressure is controlled at 0.
06~0.
12MPa, and the downblowing steam pressure is controlled at 0.
015~0.
03MPa; Realize a small amount of high pressure upblowing and increase low pressure downward to achieve the distribution of steam according to gasification needs, so as to minimize comprehensive energy consumption
.
A set of automatic control system supports 8 furnaces
.
The new special automatic control cabinet realizes the precise control of valves, which can control up to 16 gasifiers
.

In the time selection of secondary steam, according to the principle of full use of secondary steam in the recovery time, this technology realizes the introduction of a small amount of steam in the recovery state, improves the blowing efficiency, shortens the secondary steam as much as possible in the up-blowing stage, and reserves more high-level heat energy for downblowing and
gasification.
The optimal combination of steam recovery and N2 is implemented to ensure a recovery time of not less than 4 seconds, effectively recover the steam, and avoid the problem
of gas backflow in the switching process.

(Positive)