 Soil sealing compositions and methods |
| I claim: 1. A method of reducing the permeability of soil to water, the method comprising forming a ... |
|
| Process involving breaking of aqueous gel of neutral polysaccharide polymer |
| I claim: 1. A process of breaking an aqueous gel in which the gelling agent is a reducible ... |
|
| Hard coating agents comprising fluorine-containing acxylate copolymers |
| We claim: 1. A curable composition for producing a hard coating of low refractive index consisting ... |
|
| Pipeline padding system |
| The present invention provides apparatus for laying a trench bed layer consisting of fine grained ... |
|
| Covering for waste depositories |
| As shown in FIG. 1, a sandwich plate 21.1 is included in a covering for the surface of a ... |
|
| Mobile train for backfilling tunnel liners with cement grout |
| The present invention comprises generally a machine for grouting an annular cavity formed ... |
|
| Utilization of dry scrubber waste materials |
| I claim: 1. A process for preparing a cured compacted product from dry flue gas scrubbing waste ... |
|
| Fiber reinforced soil and method |
| I claim: 1. Reinforced soil having improved engineering properties for construction and excavation ... |
|
|
Separation of suspended solids from phosphate tailings
| Details |
Inventors: Thomas, James P.;
Assignee: Amstar Corporation (New York, NY)
Primary Examiner: Hruskoci; Peter A.
Assistant Examiner:
Attorney, Agent or Firm: Cooper, Dunham, Clark, Griffin & Moran
A process for separating suspended clay and sand solids from the slimes of phosphate tailings is described. The suspended solids are rapidly agglomerated and a relatively dense sludge which settles to the bottom of the separation vessel is formed. The sludge may then be discharged into settling ponds for dewatering and compaction. |
|
DETAILED DESCRIPTION OF THE INVENTION The process of the present invention is begun by introducing a settling aid or flocculating agent to the slimes of phosphate tailings which contain solid clay particles suspended in water.
The slimes may also contain finely divided sand along with the suspended clay solids.
It has been found that the percentage of clay recovered in the sludge is greater if the feed slime contains clay and sand in a 1:1 ratio by weight than if no sand is present in the feed slime.
Thus, in one embodiment of the invention, finely divided sand is added to the slimes so that the feed slimes contain finely divided sand and clay particles in a 1:1 ratio by weight.
The settling aid or flocculating agent causes an initial, at least partial agglomeration of the suspended particles and a slurry is formed.
Settling aids or flocculating are described in U.
S.
Pat.
No.
3,523,889.
The settling aids disclosed therein include the groups of polyelectrolytes, and, more specifically, the group of organic copolymers of acrylamide having molecular weights estimated at between two and three million.
It should be understood that any settling aid or flocculating agent which causes agglomeration of phosphate tailings to a substantial degree can be used in the process.
However, the group of anionic, high molecular weight polyacrylamide resins work best.
Particular polyacrylamide resins of this type useful in carrying out the invention include a number of commercially available products.
Betz 1420, available from Betz Manufacturing Corp.
, has been used successfully.
Andco AR 101, manufactured by Andco, Inc.
, which is also an anionic polyacrylamide resin but has a lower molecular weight than Betz 1420, has also been used successfully.
Preferably, the settling aid is added continuously to the suspension in the feed line leading to the separation vessel.
The settling aid should be added at a point in the feed line which insures adequate dispersion.
It may be desirable to add the settling aid at more than one point along the feedline
|
|
Gutter-related 
