What are the reasons for the high dust content in the process gas at the outlet of the carbon black scrubber tower? What harms will it cause?

The gasifier has a high load and fast gas flow velocity. There is little washing water, and the defoamer is damaged. The downcomer of the carbon scrubber tower has fallen off. The Venturi provides less water supply. The hazards include blockages in the tubes of the converter, an increase in the pressure difference within the converter, as well as the accumulation of substances on the surface of the catalyst, which reduces its effective surface area and thus affects the reaction process.

It is also related to the structure of the equipment, resulting in poor dust removal efficiency.

If it goes from gray to low iron, it will also contaminate the solution.

A high dust content in the process gas indicates that the washing effect is not ideal. Considering the actual production conditions, there are several reasons for this: the liquid level in the gasification furnace is low due to excessive water content, which results in suboptimal washing efficiency and makes it easy for dust to reach the subsequent systems ； The insufficient water volume in the venturi scrubber results in suboptimal wetting, which in turn leads to poor cleaning efficiency of the process gas during its secondary washing in the carbon scrubber tower ； The liquid level control in the carbon scrubber is too low, or the water supply to the upper trays is not adjusted in a timely manner according to the gasification load. The process gas passes through the gasifier and then to the carbon scrubber, where it undergoes multiple stages of washing. These are the main factors that affect the efficiency of this washing process; of course, equipment issues cannot be ruled out either. Damage to the demister is likely only to exacerbate the problem of water contamination in the process gas, and it has little to do with the high dust content in the gas. Regarding the venturi scrubber, the operating procedures generally state that it should be activated once the system pressure reaches 1.0 MPA. According to available information, this is done to prevent the formation of air blocks, but I don’t think it has a significant impact. It’s best to activate this device before starting up the gasifier; otherwise, when the process gas containing dust passes through this area, it can easily cause blockages, which in turn affects the water flow used in the venturi scrubber. Once a blockage occurs, it becomes difficult to increase the water flow. I’ve encountered situations where even with the control valve fully open, the water flow still wouldn’t increase :):).