J.r. Simplot Company

Roger B Humberger

Laurence W Bierman

Joseph G Harrington

Samuel M Polinsky

Michael L Orr

Gary L Long

Charles H Schwartz

David A Hempel

Jack Lee Smith

Charles Raymond Crowley

A process for in situ immobilization of metals in waste stack affected zones including a waste stack and any adjacent boundary zone. One form of the process includes: (a) forming at least one treatment passageway which extends within the waste stack affected zone; (b) injecting a treatment liquid into the treatment passageway; said treatment liquid including at least one microbe nutrient which is capable of sustaining activity of the at least one microbe; (c) providing at least one microbe in sufficient proximity to the treatment passageway to receive treatment liquid therefrom; said at least one microbe being capable of growing in the presence of said treatment liquid; said at least one microbe also being capable of producing microbial sulfides which are sulfide by-products of microbial activity in the waste stack affected zone; (d) reacting the microbial sulfides in situ with metal ions or metal-containing compounds contained in said waste stack affected zone to form metal sulfides; (e) reducing solubility of the metal ions or metal-containing compounds contained in the waste stack affected zone as a result of forming the metal sulfides; and (f) inhibiting the migration rate of metal ions or metal-containing compounds within or from the waste stack affected zone.

In-situ treatment of waste stacks, soils or earth materials to

In situ immobilization of metals in waste stacks and waste stack

Ores containing mineral values are separated into two slurries, one having primarily fine particles and gangue and the other having primarily coarse particles. The slurry having fine particles and gangue is adjusted to a solids content of less than about 15 percent, as necessary, and then conditioned by the addition of appropriate promoter reagents, a flotation collector, and a froth modifier. The gangue, containing a disproportionate share of impurities, is floated in a column flotation cell wherein the fine particulates are not mechanically agitated, and removed. The remaining fine particulate underflow, containing a disproportionate share of the minearl values, is then processed directly, or combined with the slurry containing the coarse particulate to yield a flow having reduced impurity content and increased recovery of the mineral values.

Process for beneficiating ores containing fine particles

A process for the selective recovery of cadmium, molybdenum, zinc, nickel and other metal values from wet process phosphoric acid and other acidic to slightly basic carrier solutions, wherein the metal-bearing solution is contacted with an organophosphene extractant to precipitate the metal values for subsequent separation from the solution. Separation may be effected by mechanical means or by scrubbing with a water-immiscible organic solvent such as kerosene for subsequent recovery of the metal values. The metal specie recovered is determined by the concentration of the organophosphene, which may be selectively adjusted to recover a series of metal values in a sequence of stages.

Process for the recovery of cadmium and other metals from solution

Methods for control of excessive corrosion in wet process phosphoric circuits are effected by oxidation of reduced ion species in the acid with maintenance of EMF value of the acid above about 190 millivolts (S.C.E. reference) through the digestion circuit. Supplementary monitoring is by a ceric red-ox titration procedure. In one embodied form, the present invention is utilized to control corrosion in a phosphoric acid plant digestion system (and subsequent processing equipment) operating by a dihydrate (gypsum) process even when such a process employs a calcined western U.S. phosphate ore feed from a relatively highly carbonaceous ore. The invention is also applicable for treating wet process phosphoric acid in phosphoric acid plants having a digester system operating by a hemihydrate process. In a presently preferred embodiment, additions of manganese dioxide to a primary digester in a sufficient amount effective to achieve an EMF value over about 190 millivolts will significantly control the occurrence of excessive corrosion in phosphoric acid circuits. In yet another preferred embodiment, an oxygen autoclave oxidation is used to oxidize the reduced ion species present in the acid to inhibit corrosion.

Method for the control of excessive corrosion in phosphoric acid circuits

Methods for the control of excessive corrosion in phosphoric acid

This invention relates to novel fertilizer particles having an inner core and an outer water permeable sulfur coating; to a method of preparing these fertilizer particles by contacting a particulate core material in a fluidized bed, or other suitable coating apparatus, with molten sulfur which solidifies upon the core material; the process preferably being conducted in a fluidized bed having an inert atmosphere in the material contacting zone. This invention is particularly useful in preparing triple superphosphate fertilizers with a water permeable coating of elemental sulfur.

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Pocatello, ID, United States of America

Roger B Humberger