摘要 |
<p>An apparatus and method for de-inking waste paper pulp using a foam flotation process to recycle printed waste paper for the manufacture of new paper. Pulped printed paper is fed as a slurry to an inlet of a shallow tank. Internal guide walls in the tank establish a flow path from the inlet to an outlet. The walls are sized and positioned to create a generally uniform cross-sectional flow area. A plurality of modules are disposed along the flow path. Each module includes at least one injector that aerates the flow and an extractor that removes floated ink foam. A portion of the flow from each module is recycled to an upstream module, preferably by a conduit and associated pump. In a preferred form, an injector (or injectors) alone located at the inlet is fed by the next downstream module and an extractor alone is located near the outlet. The invention also includes a main recycling loop from the downstream end of the flow path to the upstream end. This main recycling loop has a large flow rate compared to the recycled flow between the modules.</p> |