| 摘要 |
<p>1,205,291. Filter. NEPTUNE MICROFLOC Inc. 28 Feb., 1968 [2 March, 1967], No. 9605/68. Heading B1D. [Also in Division C1] A filter has media graded from coarse to fine in the direction of flow. The media have at least three different specific gravities with the higher SG being associated with the lowest particle size. The particles are mixed: to give an increasing number of particles in a downward direction. The filter is backwashed in two stages.</p> |
