摘要 |
Sensing means (10), which may employ nuclear magnetic resonance, senses the hydrogen content of the water in the coal slurry and provides a signal representative thereof. Control means (34) operates valves (7, 16) selectively to pass water through the sensing means (10) in place of the slurry so that the sensing means then senses the hydrogen content of the water. The control means controls a switch (40) to switch the output of the sensing means when the valves are operated whereby to provide a signal representative of the hydrogen content of the water. Output means (56, 60, 63) responds to the two representative signals and provides a signal representative of the coal content of the slurry. |