Abstract
The present writer has made it clear that the percentage of sulphur content of a coal differs remarkably from each other even among the coals produced from the same coal-field, and so lays stress on the necessity that those who propose to study sulphur content of coal should deal directly with the state of its distribution instead of its average percentage.
From this point of view, the writer made a histogram of the distrubution of sulphur content in coals at each stage of their coalification, studied the correlation which the analytical values of sulphur bear to those of H/C, 0/C, volatile matters and moisture of various coals, made other stochastical studies, and, as a consequenge, has drawn inferences as follows:
(1) Sulphur contained in coal was appended after the deposition of coal, and the histogram by its content varies according to the stage of coalification.If one classifies coals into three groups according to the rate of sulphur content-high, l ow and inbetween, the histograms show that high-oxygen coals consist chiefly of low-sulphur coal group plus a few high-sulphur coals, few of them lying between these two groups, and that, in the case of low-oxygen coals, the number of in-betweens incre se while that of high-sulphur coals decreases to the extreme degree.The decrease of hydrogen content keeps pace with that of sulphur content, and almost all the low-hydrogen belong, not to the in-between group, but to the low-sulphur group.
(2) If a coal-seam was affected by the heat of more than a certain degree of temperature, the coalification of the coals produced from it is proved to be influenced by the existence of sulphur in some ways.It promotes the decrease of the rate to of oxygen consistently, while it tends to increase that of hydrogen content, though in this latter case there are some exceptions.
(3) The sulphur content has an effect on volatile matters only inasmuch as the sulphur itself vaporizes.The writer concludes that it does not tend to decompose or condense organic matters of coals.
(4) The effect of sulphur on moisture is quite variable.
