Abstract
The boiler as a steam generater is used in various field from heating for buildings to thermal power stations. In these boilers and solution in piping facility, scale or sludge is produced. Researches on the composition of these substances have been carried out, however, a detailed analysis of properties of iron compounds is not yet available. So, in this research, we looked especially at ferromagnetic substances. One particularly interesting finding was that these substances contain as much as approx. 20-25% of ferromagnetic particulates (ferrite) such as magnetite (Fe3O4). Average particle size of this ferrite is ultrafine particulate of 17-27nm. And value of saturation magnetization is 65-85emu/g by correcting the contented of calcite mixed and non-magnetic layer part on particle surface. And this value is nearly equal to Fe3O4 of bulk.
