BRIQUETTED COAL

Taranaki Daily News, 5 December 1929, Page 3

BRIQUETTED COAL

A SMOKELESS FUEL MANUFACTURE IN WAIKATO. REVOLUTIONISING THE INDUSTRY. Waikato district collieries have been hard hit by the advent of hydro-electric power, but efforts are being made to combat the consequent loss to the market by presenting slack coal formerly used extensively by the Auckland Power Board in a form for use by other consumers. “Government hydro-electrical power has effected the coal industry right throughout New Zealand, but probably more seriously in the Waikato than elsewhere,” stated the president of the New Zealand Coalmine Owners’ Association (Mr. W. D. Holgate) in presenting his report to the annual meeting in Wellington. “The Waikato coal mines have been supplying the Auckland Power Board with large quantities of slack coals each year for several years past. The supply of current from Arapuni station has done away with the use of the board’s steam plant at Auckland, and has destroyed the market for the coal formerly used. Anticipating this loss of market, the Waikato coal companies have investigated the English and Continental systems of coal distillation, with' the object of converting the slack formerly used by the Power Board into fuel for other consumers. Many bulk samples were sent to England and Europe for experimental treatments. . GERMAN PROCESS ADOPTED. “Early in the investigation it was indicated that the process finally adopted would have to come from Germany, because the coals there are of the same character as the Waikato coals. There are several German processes, but the one finally decided on by the Waikato companies is known as the Lurgi process, with the following stages of treatment: — (1) To carbonise a lignite or brown coal at such a temperature as would leave between 7 per cent, and 10 per cent, of volatile matter in a sejnicoke; (2) to distill tar products, z fuel oil and pitch; (3) to briquette the'whole or part of the semi-coke, using, the pitch produced in the second stage as part,of the binder.

CAPACITY OF PLANT. “The semi-coke, which is the product principally aimed at by the Waikato companies, will amount to 50 per cent, of the weight of the original coal. This fuel is practically smokeless and sparkless, and is guaranteed to have a certain calorific value of over 12,500 B.T.U.’s. It is believed that this fuel will be entirely suitable for railway use, and also for domestic water-heaters, for domestic purposes generally and for all power plants. The capacity of the new plant now ordered is 40,000 tons of smokeless high-grade briquettes per annum, 2000 tons of deisel oil, 3200 tons of fuel oil, and 2900 tons of pitch. The plant can be added to in units as may be desired. “The enterprise shown by the companies in connection with the new treatment deserves the commendation of the public,” adds the report. “They are the pioneers in a new development of the coal industry, which may revolutionise its whole outlook.”