Transportation issues in pulverized coal gasification
Thread Content
As a process with relatively high efficiency, pulverized coal gasification has been recognized by industry peers; however, it requires high investment, the safety of pulverized coal is inferior to that of coal water slurry, and because pulverized coal is difficult to transport, its operating pressure is below 4.0 MPa, whereas coal water slurry can reach 6.5 MPa； How can the flow rate of pulverized coal be measured effectively and the operating pressure increased?
For information on measuring pulverized coal flow, please refer to this forum: http://bbs.hcbbs.com/thread-108246-1-2.html, where there is detailed information available
Flow measurement of Texaco water-coal slurry is carried out using electromagnetic flowmeters, with good results. The flow rate of shell pulverized coal is determined by measuring the velocity and density of the coal stream; after the density is compensated for temperature and pressure, it is multiplied by the velocity to obtain the pulverized coal flow rate.
Raising the coal powder conveying pressure to above 65 Bar is currently limited by the verification of the accuracy in measuring the coal powder velocity, as the principle involved dictates a strong correlation between it and pressure.
Ugh, I spent ages replying, only to run into problems when submitting! Did it say upstairs that the pressure should be increased to 65 bar? All existing Shell gasifiers aim to operate at reduced pressure! In fact, the pressure has already been reduced by a few kilograms! The existing speedometers are not performing well; it is suspected that there are issues with their quality.
It’s highly unlikely that the pressure can be increased any further; the risk is quite high. Measurement is a major issue, and I think the solid mass flow meters produced by an American company are quite effective
This post was last edited by Tianya Langji on 2009-6-23 at 10:48. There are simply no very good dry powder metering devices available on the market today; dry powder metering is a global challenge. We can’t keep saying that certain companies produce poor-quality products – the truth is that no company in the world makes good ones. If such devices did exist, Shell’s people wouldn’t be fools. In short: dry powder is less mature than water-coal slurry. If you want to use it, you have to take the risks. Just like SHELL, it is still in a stage where problems are emerging; these problems have not yet been fully exposed, let alone resolved. It’s better for everyone to wait and not rush to use it. For the brave ones:,D It’s useless to say anything – you planted the seedlings yourself, so you should eat the fruits yourself!
With such capabilities, it’s not a bad idea to use Shell technology. I matured through practice at a larger scale, and gained a lot as well.