The impact of raw coal quality and ash composition on the operation of SHELL units

Shell furnaces have a wide range of coal compatibility; they can successfully process coals with high ash and sulfur content, as well as various types of coal such as anthracite, bituminous coal, and lignite. This furnace type is not sensitive to the properties of coal such as activity, caking tendency, moisture, sulfur, oxygen, and ash content.

Saying so is just general – in response to the person above, but it’s hard to be specific; there’s a lot of experience involved in this

I disagree with the view on the second floor; Shell’s technology requires high standards rather than being flexible regarding the type of coal used

Objectively speaking, Shell’s claim of having broad adaptability to different types of coal remains unmatched at present. An article by Chen Jiaren in Coal Chemical Engineering 2009.2-1 (Volume 37) discusses various gas-flow bed gasification technologies. Although Shell can handle a wide range of coal types, the stable operating conditions for each type of coal still need to be determined. For a particular company or plant, it is more important to ensure coal quality stability; it is advisable not to use too many different types of coal. Comments are welcome

In my opinion, Shell’s claim of having broad adaptability to different coal types was merely a marketing statement when it first entered the Chinese market. In fact, based on the actual operation of Shell’s pulverized coal gasification units in China, their ability to handle various coal types is not much better than that of Texaco’s water-coal slurry gasification technology； At present, virtually all users of Shell’s powder coal gasification technology in China employ coal blending as a method to address the impacts of frequent changes in coal types on the gasifiers and other associated systems. In fact, coal blending is used to varying degrees in various coal gasification technologies; from this we can see that the adaptability of Shell’s powder coal gasification process to different coal types is not as remarkable as Shell claimed initially ； In my opinion, the most suitable coal type for Shell’s pulverized coal gasification process is one with an ash content in the range of 8–15%, and a ash fusion point of around 1400 degrees Celsius. The volatility content of the coal should not be too high, otherwise certain problems may arise in the pulverized coal processing unit. As for other properties of the coal, the requirements imposed by Shell’s pulverized coal gasification process are relatively lower!

Based on my experience with various coal types used for personal purposes, Shell gasification does not require very high standards regarding the coal quality: an ash content of 8–30%, a ash fusion point of 1250–1600 degrees Celsius, and a lower heating value of at least 5200 kcal per unit weight. A volatile matter content of 5–30% is also sufficient. The other parameters are similar across different coal types; the only requirement is that the ash fusion point should be between 1300 and 1400. If this value deviates too much, corrective actions need to be taken. Additionally: the shell gasifier itself has no specific requirements regarding sulfur content; of course, the lower the better. However, due to the needs of the downstream gas purification processes, there is still a certain range allowed for sulfur content. As for particularly special types of coal, I dare not make any judgments about them since I have never used them. In short, shell gasification does not have high requirements regarding the type of coal used, but different types of coal do result in significant differences in terms of operational requirements. This post was last edited by shell Vaporize job hunting on 2009-3-29 17:58.]