The gas of QHD30 1 is mixed gas and mainly from the coal derived gas from pre Tertiary source rocks.

QHD3 0 1气藏的天然气属多源混合气，主气源为前第三系的煤成气。

youdao

The coal quality of Xiangxi stage is not good and stable but the coal appears dark mud, well develops shale and has high evolution level, which is favorable to create coal derived gas.

香溪煤系煤质较差，极不稳定，但该煤系暗色泥、页岩发育，演化程度较高，有利于形成煤成气。

youdao

For effective desulfurization and deashing of high-sulfur coal with its use of usual magnetic separation device, a surface magnetism enhancement of coal-derived minerals is a new key technology.

煤系矿物的表面磁性强化是利用通常磁选设备实现高硫煤脱硫脱灰的新型关键技术。

youdao

Forbes energy blogger Robert Rapier wrote about the potential of coal-derived ethanol a few years ago.

FORBES: A Name You Need To Know In 2011: Celanese

One big seller: the coal-derived carbon material that is used in the smelting of aluminum, which in turn is in strong demand in the airplane and construction industries.

FORBES: Magazine Article

Originally they were derived from coal-tar, the black viscous waste product left over from distilling coal for gas.

FORBES: Jelly Beans: Which Color Is Most Popular At Easter? Why We Love Colored Foods