BASIC SLAG.

Taranaki Daily News, Volume LVII, Issue 275, 30 April 1915, Page 8

BASIC SLAG.

(To the Editor.) Sir, —" Farmer" gives an opinion to the effect that we cannot produce basic slag in New Zealand, owing to the absence of high percentage sulphur and phosphoric iron ores, especially in Taranaki, and in New Zealand generally. I would point out to " Farmer" that an opinion is not a fact. Here are some facts for " Farmer" to digest with regard to our method of slag manufacture. In the lirst place, the ironsand contains sulphur and phosphorus. The limestone we use is a phosphate limestone. The fluxes and binding agents we use also contain sulphur and phosphorus, The fuel and reducing agents also are rich in sulphur and phosphorus. These elements are passed into the slag direct from our steel-making furnace. We can raise our phosphoric contents or lower same at will during any stage of the smelting operations, and put a basic slag on the market containing from 10 to '25 per cent, phosphoric acid, sufficient for all purposes. Comparative tests have been made with imported ,slag and slag we have made, which has given equal results. Mother Nature has placed the raw material within a radius of twenty miles of New Plymouth. This, is a distinct advantage. As " Farmer" lives at Mokau, possibly he may stumble on sulphate of lime deposits there. They exist close at hand, and are very valuable. In conclusion, I may say it , would be a bad day for New Zealand i,' we toillil. not make lJasic slag equal to anything imported, If "Farmer" understood the process wo employ, he would not make such damaging statements as "slag not worth carting away," etc. —I am, etc., .T. C. SMITH. New 'Plymouth, April, 29.