A NEW OUTLET

Evening Post, Volume CVIII, Issue 131, 29 November 1929, Page 9

A NEW OUTLET

CARBONISED COAL

A WAIKATO INDUSTRY

VALUE OF EESEAftCH

Owing to the effect of Government hydro-electric power on the coal industry, mine owners have -t>een on the look-out for some other outlet for their slack coals. Particularly haa this been the case in the Waikato district.

Commenting on this question at the annual meeting of the Coal Mine Owners' Association yesterday, the president (Colonel W. D. Holgate) said the Waikato coal mines had 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 had done away with the uae of the board's steam plant at Auckland, and had 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," said Colonel Holgate. "Many bulk samples were sent to England and Europe for experimental treatments. A firm of engineers in England was engaged to supervise all experiments, and report upon the results and the suitability of various English and Continental processes, -which had been thoroughly tested for use with New Zealand brown coals. Early in the investigation "it was indicated that the process finally adopted •would have to come from Germany, the reason for this being that while the English coals are bituminous the German coals are of the same character as the Waikato coals. A plant which will treat bituminous coal is not suitable for brown coal, and the Germans, having confined their attention to the treatment of their own brown coals, have produced a process which has become an established commercial success and is producing the high-grade fuel necessary for German. industries. There are several German processes, but the one finally recommended to the 'Waikato companies is known as the Lurgi process, and is owned by the Metal Bank Company of Frankfurt, Germany, which company has a capital of forty-five million pounds sterling. In view of the satisfactory reports upon this process received from their advising engineers, the Waikato companies formed and registered a new company, and have ordered "a two-unit plant guaranteed to 'treat 250- tons of slack coal per day. SUITABLE FOR RAILWAYS. "The stages of the treatment in the Xnirgi process are:—(l) 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 semi-coke; (2) to distill tar products so as to produce a dieael oil, fuel oil, and pitch; (3) to briquette the "ivholo or part of the semi-coke, using the pitch produced in the second stage as pa it of the binder. 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.TJ.'s. It is be- . lieved 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 diesel 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. They are the pioneers in a new development of the coal industry which may revolutionise its whole outlook. The plant has now actually been ordered and the first instalment of the cost paid. There will therefore tie no delay in its erection, and completion. VALUABLE EESEARCH WORK. "The Scientific and Industrial Research Fuel Committee has rendered great assistance in helping the Waikato companies to choose a suitable process for carbonising their slack coals. They have been able to get information through the Division of Scientific Eeseareh, London, on various processes in England. In addition, the experimental work carried on at the Government laboratories, Wellington, on Waikato coals has checked the figures and results given them by the Lurgi people in Germany. The Fuel Committee is now working on a blend of bituminous and lignite slack, with the view of briquetting slack coal in. the South Island, and also on methods of dealing with highly swelling coals. Tney have also cabled for a small briquetting plant in order to briquette the blended coals and to experiment on a suitable binder for same. I am pleased to state that the work done by the committee at the laboratories is interesting, not only to the coal owners connected with the industry, but to members of Parliament who have paid visits to the laboratories to obtain information. From my own personal experience as chairman of the Fuel Committee, I can conscientiously state that the Scientific and Industrial Research Fuel Committee has justified its existence and the support given by the coal owners."