Abstract: A method of dissolving mineral salts comprising contacting the mineral salts with a solution of water, an additive consisting essentially of six moles of 1-hydroxyethane, 1, 1-diphosphonic acid mixed with one mole of hydroxymethylene phosphonic acid, phosphonoformic acid, sulfamic acid, oxalic acid, hydroxyacetic acid, 2-amino ethane sulfonic acid, or fluoroboric acid and neutralized to a pH of 7.0, and a polymeric dispersant.

Abstract: Dirty diphenylamine solution is pumped from a reservoir (12) first through a cyclone separator (28) and then through a media filter (50) and back to the reservoir (12). A first large flow rate pump (30) is used to cause flow through the cyclone separator (28). A second lower capacity pump (52) pumps a portion of the solution that is delivered out through the cyclone separator (28) into the inlet (48) of the media filter (50). The remaining portion of the outflow from the cyclone separator (28) is directly returned to the reservoir (12). Fresh water via a conduit (78) and then compressed air via a conduit (82) are flushed through the filter (50), to wash chemical out from the filter (50) and carry it into the reservoir (12). Then, fresh water is directed back in the reverse direction through filter (50), to backwash the filter (50). The water used for backwashing is dumped via conduit (90).