16 a the gas industry, caused the attention of inventors to be turned to the enrichment of coal gas.
It has elaborate reliefs in repousse work, cast canopies and minute statuettes, with the further enrichment of translucent coloured enamels.
The mining product next in value to coal in 1908 was copper, taken chiefly in Carbon county in a zone of brecciated quartzite underlying schist, the original ore being chalcopyrite, with possibly some pyrite, a secondary enrichment, which has produced important bodies of chalcocite in the upper workings, but these are replaced by chalcopyrite at greater depth.
The following analysis gives a fair idea of the composition of an average sample of gas made from coal, purified but without enrichment: Ioo 00 These constituents may be divided into - (a) light-yielding hydrocarbons, (b) combustible diluents and (c) impurities.
Very many attempts have been made to utilize tar for Enrich- the production and enrichment of gas, and to do this meat by two methods may be adopted: tar.
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.
Undoubtedly the best process which has been proposed for the production of oil gas to be used in the enrichment of coal gas is the" Young "or" Peebles "process, which depends on the principle of washing the oil gas retorted at a moderate temperature by means of oil which is afterwards to undergo decomposition, because in this way it is freed from all condensible vapours, and only permanent gases are allowed to escape to the purifiers.
The fundamental objections to oil gas for the enrichment of coal gas are, first, that its manufacture is a slow process, requiring as much plant and space for retorting as coal gas; and, secondly, that although on a small scale it can be made to mix perfectly with coal gas and water gas, great difficulties are found in doing this on the large scale, because in spite of the fact that theoretically gases of such widely different specific gravities ought to form a perfect mixture by diffusion, layering of the gas is very apt to take place in the holder, and thus there is an increased liability to wide variations in the illuminating value of the gas sent out.
One of the most generally adopted methods of enrichment now is by means of carburetted water gas mixed with poor coal gas.
Important factors in the use of carburetted water gas for enrichment are that it can be made with enormous rapidity and with a minimum of labour; and not only is the requisite increase in illuminating power secured, but the volume of the enriched gas is increased by the bulk of carburetted water gas added, which in ordinary English practice amounts to from 25 to 50%.
The universal adoption of the incandescent mantle for lighting purposes has made it evident that the illuminating value of the gas is a secondary consideration, and the whole tendency now is to do away with enrichment and produce a gas of low-candle power but good heating power at a cheap rate for fuel purposes and incandescent lighting.
The inspiration of early belief has disappeared; the ruling motive of the mollahs (priests) is the thirst for personal enrichment, and the people no longer follow the khojas or theologians.
On his return home Snorri sent his son to the king as a hostage, and made peace between Norway and Iceland, but his power and influence were used more for his own enrichment and aggrandizement - he was logsogumaar again from 1222 to 1232 - than for the advantage of the king.
The freezing of molten cast iron of 2.50% of carbon goes on selectively like that of these steels which we have been studying, till the enrichment of the molten mother-metal in carbon brings its carbon-contents to B, 4.30%, the eutectic 1 carbon-content, i.e.
This led to the enrichment of the archivolts and imposts with that peculiar type of conventional foliage which characterizes Mahommedan work, and which in this case was carried out by Coptic craftsmen.
The further enrichment of the object by enamels and inlay of other metals was practised at a very early period by Assyrian, Egyptian and Greek metal-workers, as well as by the artists of Persia and medieval Europe.
The " Welsh process " closely resembles the English method; the main difference consists in the enrichment of the matte by smelting with the rich copper-bearing slags obtained in subsequent operations.
Ordinary gas, thereby enriching it, but as the supply became limited and the price prohibitive, other methods were from time to time advocated to replace its use in the enrichment of illuminating gas.
Petroleum products are also largely utilized in gas manufacture for, (1) the production of " air-gas," (2) the manufacture of oil-gas, and (3) the enrichment of coal-gas.