Technikatörténeti szemle 4. (1967)

TANULMÁNYOK - Rácz István–Soós Imre–Szőkefalvi-Nagy Zoltán: Timsógyártás Magyarországon a XVIII. Században

I. SOÖS — Z. SZÖKJEFALVI-NAGY ALUM PRODUCTION IN HUNGARY IN THE 18TH CENTURY The first Hungarian alum factory was erected at Párád in the Mátra mountain, in the last third of the 18th century. It was F. Markhót, an Eger physician who discovered the alum spring at Párád in 1763, and had alum made of it. The alum factory flourished in the hands of the mining company, founded in 1782, but went bankrupt through constant altercations with the landowner. The Orczy-family acquired the alum factory in 1816 and rebuilt it. However — as a consequence of richer alum stone findings elsewhere in Hungary — the factory worked at a loss and at last they had to sell out in 1839. The first Hungarian alum factory was shut shortly afterwards. Hydrothernially conversed andésite served for the alum production at Párád. The raised rock had been put into an oven and heated under the direction of the „rostmaster". Here the sulfide contents of the stone oxidized into sulfate. Higher temperature resulted in sulfuric acid loss. The roasted stone was kept in the mine court, under regular wetting. The hydrous alum was thus formed and after 1—2 months of ageing it was solved out with hot water in the lye-house in wooden vats. The liquid was roughly settled in the solving vats and they kept it in larger wooden vessels till total settling. A pump pressed the cleared liquid into the „foundry", where the panning took place in lead cauldrons till the material reached a density, economically crystallizable.

. The lead cauldrons were repared by the factory, even new ones were moulded by them. The condensed juice was crystallized in wooden vats in the lye-chamber. After two days the matrix was decanted, taking down the hoops, the vats were dismantled to obtain the crystalline alum. The crystals were washed and resolved in clean hot water. After 8—10 days of crystallization clear crystals were produced, to be packed in so called centner barrels in which the alum was delivered first of all to Pest but to more distant places as well. Though the Párád alum factory has been closed for more than hundred years, its history is important as one of the first stages of the Hungarian chemical industry.