Wet pellets of carbon black are dried to produce dry pellets by means of a two-step process. In the first step a bed of wet pellets is fluidized by means of a heated gas and the pellets are thus partially dried. In the second step the partially dried pellets from the first step are subjected to additional drying while in a nonfluidized state, e.g. pellets from the fluidized bed are heated and subjected to a mild, mechanically produced tumbling action during the second step.
This application is a division of U.S. patent application Ser. No. 47,085 filed on June 17, 1970, now U.S. Pat. No. 3,740,861 and assigned to the same assignee as this application.
Washing and disintegrating means serve to wash and disintegrate the waste material and to continuously deliver the resulting washed and disintegrated material. A first conveyor serves to receive said washed and disintegrated material from said washing and disintegrating means and to remove water from said washing and disintegrating means and to remove water from said material. A dirt separator serves to receive said washed and disintegrated material from said first conveyor and to remove dirt from said washed and disintegrated material and to deliver the resulting cleaned material. A second conveyor serves to receive said cleaned material from said dirt separator and to remove water from said cleaned material. A water collector serves to receive water removed by said second conveyor. A return conduit serves to deliver water from said water collector to said dirt separator. Continuously operable drying means serve to receive said cleaned material from said second conveyor and to dry said cleaned material and to continuously deliver the resulting dried material. A buffer serves to receive said dried material from said drying means and to intermittently deliver said dried material. Intermittently operable agglomerating means serve to receive said intermittently delivered dried material from said buffer and to transform said dried material into an agglomerate.
A device for preparing a very homogeneous and finely divided fine-ceramics mass from ceramic raw materials, liquids, aggregates, and similar materials, whereby the starting materials are finely ground, and liquid is added and later partly removed. The starting materials are ground dry or moist and all or some of the starting materials are first allowed to fall free in and through an upright container while being contacted with all or some of the liquid, which is injected in subject to turbulence, and then agglomerated into a granulate.
An apparatus for drying pellets of particulate material such as carbon black is characterized by a columnar drying vessel containing inclined trays or screens positioned so that the pellets or particulates roll from screen to screen down the column. Preferably, the pellets are subjected to countercurrent flow of drying gases while flowing down the screens. In other aspects, carbon black is pelleted with a nonaqueous liquid pelleting fluid and dried with vapors of the same pelleting fluid.
An apparatus for drying pellets of particulate material such as carbon black is characterized by a columnar drying vessel containing inclined trays or screens positioned so that the pellets or particulates roll from screen to screen down the column. Preferably, the pellets are subjected to countercurrent flow of drying gases while flowing down the screens. In other aspects, carbon black is pelleted with a nonaqueous liquid pelleting fluid and dried with vapors of the same pelleting fluid.
