A TALK ON WASTE

Otago Witness, Issue 3274, 13 December 1916, Page 60

A TALK ON WASTE

The monthly luncheon given in connective with the Expansion League took place at the Y.M.O.A. rooms on Friday. Mr A. Bathgate (president; occupied the chair, and there were over 20 members present. Dr -J. K. H. Ingns (chairman of the University Professorial Board), who has given a great deal of study to the question of the utilisation of by-products in connection with manufactures, gavo a brief and very interesting address of "Prevention of Waste."

Sulphuric acid, said the speaker, was an extremely important starting point for many processes, and it was necessary for it to be available at low cost. In New Zealand the cost was unduly high, and there could be very little doubt either that the manufacturers were making- great profits or they did not conduct their manufactures economically. As a result we had all the ammonia from the gasworks shipped to Australia, although it only needed (heap sulphuric acid to convert it into ammonium sulphate—an important manure. The manufacture of caustic soda had not been undertaken in New Zealand, but apparently something like 1500 tens were used per year, and a certain amount of chloride of lime. It looked as if there was room for a new industry, though possibly there would be an excess'of chloride or bleaching powder. Probably* this excess couid be utilised in treating mineral ores. Tho starting point would have tb bo common salt, and this must either be imported or be made cheaply from salt water. Large waste undoubtedly occurred in the burning of coal. Inefficient furnaces meant lost fuel in the smoke and ash and wasted heat. But in the largest works it ought to be possible to recover ammonia just as in gasworks. In England quantities of coal slack were converted into a gas which was suitable for gas engines, and the ammonia was also recovered. In many New Zealand mines much of the small coal was wasted altogether. In the gas works also there was often waste —the Gas Works Committee of a corporation was seldom keenly interested in the scientific efficiency of the works, and did not encourage its gas engineer to conduct experiments, perhaps at considerable cost, to utilise his by-products and so keep expenses down. Two other possible sources of waste were worth mentioning. In wool-scouring all the soap and tho fat washed out were wasted, even although these might be partly recovered and would have a commercial value. In the wood industry there was a great amount of sawdust and scrap either not used at all or only burnt. In other countries valuable products were manufactured—oxalic acid, acetone acetic acid, w.ood spirit, and occasionally ordinary alcohol.' Also considerable research was needed upon proper treatment of certain timbers to improve tho seasoning and durability. In conclusion, said Dr Inglia, it should perhaps be emphasised that a properly trained chemist was by tho very nature of his research training, often able to give advice in regard to technical processes even though he might not have had previous experience of tho particular processes in question. His training cultivated a critical spirit, and the wealth of experiences in other processes enabled him to grasp rapidly the new details, and to see at once where possible improvements might be effected. Unfortunately, manufacturers were apt to consider that v.o one could teach them anything in regard to their own particular manufacture and to be suspicious of anvone seeking information for fear he should pick their brains and then set up in opposition. Dr Tnsrlis was accorded a hearty vote of thanks for his instructive address.