| 摘要 |
<p>A method for the production of fibrous plaster boards for which a suspension is prepared from wet-digested fiber material and calcium sulfate dihydrate, the suspension is formed into a board with removal of water, and the dihydrate is recrystallized with heating at atmospheric pressure to a hemihydrate which is subsequently converted back into the dihydrate by the addition of water. For this purpose, the suspension is dewatered from a water content of about 300 to 600% to one of about 30 to 40% in dewatering equipment, the dihydrate is recrystallized in air and without pressure to the beta form of the hemihydrate and the water, required for setting, is aspirated through the board by suction.</p> |
