Is it possible to master the core technologies for desulfurization and denitration through reverse engineering?
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The leader asked me a question: where lies the core technology for desulfurization and denitration? First, desulfurization is carried out; I understand that there are dry and wet methods, with different mass transfer coefficients. Taking the wet method as an example, after deciding between dry and wet methods, the next step is the design of the absorption tower. Here, the space velocity v and the liquid-to-gas ratio f need to be determined. Then, based on the space velocities used in previous wet desulfurization projects, the value of v is chosen through bidding processes, which in turn determines the height of the tower. The pressure loss δp is calculated using the value of v, and this helps determine the power required for the fans. Economic analyses are then conducted, and the power consumption of the fans is calculated. The liquid-to-gas ratio determines the pumping flow rate, which in turn helps determine the power P required for the slurry pumps. From this, the number of slurry pumps and their power consumption can be determined. The total power consumption for the slurry pumps and fans, along with the amount of raw materials such as quicklime or magnesium sulfate required, is calculated to estimate the overall operating costs. If you were to undertake this project, what other parameters do you think are necessary to determine?
The denitration catalyst is the key; unless copying existing catalysts, there is no technical difficulty in other aspects – it mainly involves the calculation and determination of process parameters! !
I have only read some articles. What is most crucial for me to understand is the selection and development of efficient catalysts for denitration. The desulfurization and emission control systems at Baosteel Zhanjiang have been put into use, but it is unknown what the actual effects and operating costs are. Sometimes companies are forced to invest in technologies that seem advanced, only to have to suffer the consequences once they start using them! In my opinion, the desulfurization and denitrification of coke oven flue gas is still at an experimental stage in China at present; it’s all nothing but self-promotion by those trying to highlight their own achievements! This is just my personal opinion; please don’t criticize if you disagree!
Addressing the issue at its source is the true solution; only by designing coke ovens and coking processes that result in low NOX emissions can the problem be solved
It needs to be in line with the current realities of the industry; it’s not possible to redesign the furnaces for all sintering flue gases or coke oven flue gases. Due to environmental regulations and strict controls on production capacity imposed by local development and reform commissions, the only option is to upgrade the subsequent desulfurization and denitrification systems.
Source control does not mean simply demolishing existing facilities and building new ones; of course, it is best to make improvements to the design and processes before the project begins. Source control includes measures to address overproduction, such as adjusting the composition of the gas used for combustion, distributing the gas properly, and keeping the air excess factor within a reasonable range. Research is currently being conducted on how to adjust the composition of coke oven gas, dilute it, and lower the flame combustion temperature in order to reduce NOX emissions! !
The selection of the desulfurization process is mainly related to the choice of the denitrification process. Generally, SCR denitrification catalysts have poor resistance to sulfur, so desulfurization is carried out first followed by denitrification. If raising the flue gas temperature before denitrification consumes too much energy, dry desulfurization is the better option. The dry desulfurization process has limited ability to reduce flue gas temperature, and it does not significantly increase the flue gas humidity, which is beneficial for heating before denitrification. Zhanjiang is also adopting this approach at present.
In wet flue gas desulfurization, how is it ensured that the desulfurizing agent does not clog the tower or crystallize? Flue gas desulfurization in the coking industry is essentially a supplementary facility, with the main desulfurization workload being handled by the desulfurization systems located at the front end. Denitration depends on the efficiency and activity of the catalyst; without these two factors, nothing else can be considered a core technology.
The core of denitration is the catalyst, while the challenge lies in the process flow; the flow can be replicated, but the catalyst still needs to be purchased； There are many desulfurization technologies. In the large-scale wet process, the liquid-to-gas ratio is the key factor; even if you’re given a formula, you won’t be able to derive a result. The core of the rotary atomization semi-dry process lies in the nozzles, and it’s impossible to imitate them ； The core of the semi-dry process using circulating fluidized beds lies in the establishment of the bed layer and the ratio of recycled ash. By examining several projects, it is possible to identify patterns. If you have any questions, feel free to consult me at https://bbs.hcbbs.com/thread-1801003-1-1.html