This class of burner forms a basis on which all the later constructions of burner have been founded, but had the drawback that if the flame was turned low, insufficient air to prevent carbonization of the burner tips was drawn in, owing to the reduced flow of gas.
Sugar charcoal is obtained by the carbonization of sugar.
A volatile product of offensive odour obtained in the carbonization of bones for the manufacture of animal charcoal.
One of the most striking alterations of cell-walls is that termed carbonization, in which the substance gradually turns black, hard and brittle, as if charred - e.g.
For the withdrawal of the residual coke at the end of the carbonization, the lower mouthpiece door is opened, the barrier removed and the coke in the lower part of the retort is "` tickled" or gently stirred with an iron rod to overcome a slight adhesion to the retort; the entire mass then readily discharges itself.
The heating as well as the illuminating value of the gas per unit volume is lowered by over-baking, and Dr Bueb gives the following figures as to the heating value of gas obtained from the same coal but by different methods of carbonization: Vertical Retorts, 604 British thermal units per cub.
The higher the heat of carbonization the more naphthalene appears to be produced, and gas managers of to-day find the removal of naphthalene from the gas a difficult problem to solve.
The final solution of the question of enrichment of gas by hydrocarbons derived from tar may be arrived at by a process which prevents the formation of part of the tar during the carbonization of the coal, or by the process devised by C. B.
The earliest attempts at enrichment by oil gas consisted in spraying oil upon the red hot mass in the retort during carbonization; Enrich- but experience soon showed that this was not an econo- meat by mical method of working, and that it was far better to oil gas.