USERS OF N.Z. COAL.

Auckland Star, Volume LX, Issue 221, 18 September 1929, Page 5

USERS OF N.Z. COAL.

GAS COMPANIES PRAISED. SCIENTIFIC INVESTIGATION. SOME SUCCESSFUL TESTS. (By Telegraph.—Parliamentary Reporter.) WELLINGTON", this day. Tests carried out by the blending of different classes of New Zealand coal have proved that, by using suitable mixtures, the results for gas-making purposes are not inferior to those obtained irom the. use of imported bituminous coal, states the annual Mines Statement, tabled in the House of Representatives. During the year 192S the output of coal from the mines of the Dominion was a record, being over 70,000 tons : more than the quantity produced in any previous year. This result waa due .largely to the utilisation by the railways of more locally-mined instead of imported coal, and also to the commendable action of gas companies in obtaining greater quantities of their requirements within the Dominion. Absence of industrial trouble of a serious character has been one of the pleasing features of the coalmining industry, and this is evidence that a spirit of goodwill exists between employers and employees. With knowledge gained from investigations carried out in the Dominion Laboratory, as well as in countries abroad, it is considered that in the near i future it should be possible considerably 'to curtail coal importations, and, fcy the adoption of some of the proved carbonising processes now in operation 'abroad, eliminate much waste and secure better and greater results from carbonised fuel. Research work on coal has been continued at the Dominion Laboratory under the direction of the Coal Research Association, in which the Mines DepartJment is represented. The low temperature carbonisation of some Waikato coals has been investigated at the temperatures of 550 and 600 deg. C. Using the Fischer rotary retort installed last rear, the condensing system was modified by the addition of absorbers of activated carbon to strip the light oil from the gas. A meter was also installed accurately to measure the volume of the gas produced. A full charge for a retort is 301b of coal. The average yield, for Rotowaro coal, at 600 deg. C, per ton of coal as charged, was a residue of lO.Scwt of tar oil, 16.3 gallons of light oil; from gas, 0.9 gallons; and gas, 4215 cubic feet. The work is being extended to other chief classes of New Zealand coal. In addition to work carried out at the Dominion Laboratory, an investigation was made of conditions of stone dusting in New Zealand mines, and a report has been prepared on the subject.