Spiral separators and parts therefore

A spiral separator for separating more-desired material from less-desired material, the spiral separator comprising:

• a feed arrangement for feeding a slurry of mixed more-desired material and less-desired material;
• a spiral trough;
• and
• a splitting arrangement for off-take of a concentrate band of more desired material;
• wherein the spiral trough is configured to provide a trough floor region with an effective cross-trough floor slope which reduces by between 5 and 8 degrees in a turn immediately upstream of the splitting arrangement.

A spiral separator for providing at least partial separation of a first species and a second species, comprising:

• a feed arrangement;
• a spiral trough comprising a more upstream region and a more downstream region;
• a splitting arrangement;
• wherein the feed arrangement is, in use, arranged to feed a feed slurry comprising a mix of said first species and said second species into the more upstream region of the spiral trough at a feed entry region;
• wherein the more upstream region of the spiral trough has a trough floor region, and provides an effective cross-trough floor slope relative to the horizontal, which reduces from between 15 and 20 degrees to a cross-trough floor angle of between 10 degrees and 14 degrees;
• wherein the more downstream region of the spiral trough has a trough floor region having an effective cross-trough floor angle which reduces to between 4 degrees and 8 degrees, relative to the horizontal;
• and
• wherein the splitting arrangement is provided at or immediately adjacent the said trough floor region having an effective cross-trough floor angle which reduces to between 4 degrees and 8 degrees, to split a concentrated band of the first species from the rest of the flow in the spiral trough.

A spiral trough for use in a spiral separator for providing at least partial separation of a first species and a second species by wet gravity separation, the spiral trough comprising:

• a more upstream region, the more upstream region comprising a slurry feed region adapted, in use, to receive a feed slurry comprising a mix of said first species and said second species from a feed arrangement of said spiral separator;
• a more downstream region, adapted to be provided in said spiral separator with a splitting arrangement provided at or immediately adjacent the more downstream region, to split a concentrated band of the first species from the rest of the flow in the spiral trough;
• wherein the more upstream region of the spiral trough has a trough floor region, and provides an effective cross-trough floor slope relative to the horizontal, which reduces from between 15 and 20 degrees to a cross-trough floor angle of between 10 degrees and 14 degrees;
• and
• wherein the more downstream region of the spiral trough has a trough floor region having an effective cross-trough floor angle which reduces to between 4 degrees and 8 degrees, relative to the horizontal, immediately adjacent a downstream end of the spiral trough.