Issue with the additional washing section in the Texaco scrubber tower

1. Carbon scrubber towers typically have four layers of trays, and solid-valve slant holes are used to prevent issues such as blockages or scaling, which could lead to an increased space velocity and the entrainment of ash. Analyze your tray selection, or perform maintenance by opening it to check for blockages. 2. Controlling the outlet temperature using the amount of cleaning water is not a viable approach. First, water is added above the trays; if too much water is used, the liquid level on the trays becomes too high, which can cause gas obstruction and lead to the presence of water in the gas stream. The cleaning effect is worse. 3. The venturi cannot be removed; its function is to wet the ash or fine particles in the syngas, causing them to settle into the liquid phase and thus facilitating their separation from the gas. If it is canceled, ash in the syngas will increase.

I’ll try to answer. 1. I share Comrade Li’s view that the Venturi effect cannot be eliminated, and I support his opinion. Without the forced penetration effect of a venturi, as well as moistened fine dust, the cleaning efficiency of your current setup will certainly not be as good as it is now; only when the fine dust is soaked can it be removed thoroughly. With high gas velocities, the gas carrying fine ash stays for only a short time in each wetting tunnel, making it difficult to ensure an effective wetting effect. Several additional steps for forcibly wetting the fine ash are necessary in order to wet it thoroughly and remove it completely. 2. Your idea seems good, but I don’t think it will work; it definitely won’t work. The reason is the high gas velocity; the additional bed of scattered packing becomes turbulent under the push of the rising gas. Wet ash might yield better results, but could the gas flow resistance increase significantly? Might the gas in the system end up carrying water, and even in large quantities? It’s not impossible. 3. I’m not sure if it’s feasible to install two Venturi devices in front of the tower No, I earnestly ask for your criticism and suggestions.

The venturi cannot be removed; if it is removed, the quality of the product becomes poor. However, at Shanxi Fengxi, the venturi was removed without any problems, as their vaporization furnaces have a high water content.

It is best to minimize ash in syngas at the source. Adding more packing sections makes it hard to assess the washing effect; blockages may occur again, increasing the resistance of the system. The venturi scrubber cannot be removed; the function of the nozzle scrubber and venturi scrubber located on the syngas outlet pipeline of the gasifier quench chamber is to ensure thorough wetting of fine ash and water, so that they can be effectively removed in the scrubbing tower. The water-gas ratio can theoretically be adjusted to 1 by removing a large amount of heat from the washing system in order to lower the temperature of the syngas; however, this requires a significant amount of water to be added from outside, thereby increasing the load on the flash evaporation system and the graywater system. Furthermore, a certain water vapor ratio (1.4–1.5) is beneficial for the downstream conversion system. In my opinion, communicate more!

Regarding the method you mentioned of adding some bulk packing, my view is as follows: firstly, it increases the gas resistance, which can lead to \"liquid flooding\" in the section where the process gas reaches the tray area, and this in turn can cause water to enter the vaporizer. Secondly, there is no need to add more plain water; using a changed condensate is sufficient. Suggestions: Modify the tray design, add wire mesh defoamers, check whether the downcomers of the trays are of the appropriate size, determine what the opening ratio of the trays is, and so on.

We can also follow the approach used with four nozzles by adding a separator in front of the carbon scrubbing tower. The furnaces equipped with four nozzles here have less ash; during each inspection, it was found that there was a large amount of ash accumulated in the separator, while the amount of ash in the carbon scrubbing tower was less compared to those in Texaco furnaces, which shows that the separator does indeed work effectively.

The cyclone pre-separator at Huali University is indeed well-designed, and a venturi tube has also been installed – is that really necessary?

Can it be understood as follows: 1. Due to the short cooling time in the vaporization furnace, the crude syngas produced is not yet at a state of wet saturation; therefore, humidification via a venturi tube is still necessary? 2. If the crude syngas after cooling is already at wet saturation (as indicated by the slope of the piping, which takes anti-condensation into account), then the function of the venturi tube is mainly to cool and wash the gas? 3. Could experts tell us the temperature drop achieved by the venturi tube? Thank you

It moves the venturi from the carbon scrubber to in front of the separator, rather than adding another venturi. I’m not very familiar with the temperature drop caused by the Venturi effect, but its function is to humidify the process gas, thereby facilitating the settlement of fine ash in it. This post was last edited by Coal Miner on 2009-3-29 10:33.]

This post was last edited by GSP on 2012-11-26 09:03. Is there a schematic diagram of the Venturi flow meter?