Wrt International LLC

California Nickel Corporation

Chevron Research Company

Ada Technologies, Inc.

Resource Technology Associates

John E Litz

Charles S Williams

E Harris Lowenhaupt

Dennis L Howe

Enzo L Coltrinari

Wayne C Hazen

Robin M Stewart

Thomas E Broderick

David L Thompson

Dennis L Hoe

Systems and methods are provided for the removal and disposal of radium form an aqueous medium. The systems and methods include the removal of radium from a source by contact with either natural or synthetic zeolite. The spent zeolite is monitored for radiation levels and replaced with fresh zeolite when the level of radioactivity reaches approximately 9,000 pCi/g. Spent zeolite is disposed of at a low-level radioactive waste site. A system for monitoring and maintaining radium removal and disposal by an off-site provided is also disclosed.

Radium removal from aqueous media using zeolite materials

Methods and compositions for removing radium from drinking water using a natural zeolite.

Method for removing cationic contaminants from water using natural zeolite underloaded with transition metal ions to limit leakage of intrinsic arsenic therefrom

Systems and methods are provided for the removal and disposal of arsenic from an aqueous medium. The systems and methods include the removal of arsenic from a source by contact with either a chemically treated natural or synthetic zeolite, for example a ferric-loaded zeolite. The spent zeolite is disposed of at an appropriate arsenic disposal site. A system for monitoring and maintaining an arsenic removal/disposal system by an off-site provider is also disclosed.

Arsenic removal from aqueous media using chemically treated zeolite materials

Methods and apparatuses are provided for the removal and destruction of ammonia from an aqueous medium. The methods and apparatuses include the removal of ammonia from an aqueous medium by contact with either natural or synthetic zeolite. The spent zeolite is regenerated for continuous use, while the ammonia is concentrated as ammonium sulfate, and ultimately destroyed via combustion. A system for monitoring and maintaining an ammonia removal system by an off-site provider is also disclosed.

Method for removal and destruction of ammonia from an aqueous medium

Methods and apparatuses are provided for the removal and destruction of ammonia from an aqueous medium. The methods and apparatuses include the removal of ammonia from an aqueous medium by contact with either natural or synthetic zeolite. The spent zeolite is re-generated for continuous use, while the ammonia is concentrated as ammonium sulfate, and ultimately destroyed via combustion. A system for monitoring and maintaining an ammonia removal system by an off-site provider is also disclosed.

Apparatus for removal and destruction of ammonia from an aqueous medium

Systems and methods are provided for the removal and disposal of chromium form an aqueous medium. The systems and methods include the removal of chromium from a source by contact with either natural or synthetic zeolite that has been modified with a ferrous ion or other like substance. The spent zeolite is disposed of and replaced with freshly modified zeolite. In some cases the systems and methods are performed under de-oxidizing conditions.

Hexa-valent chromium removal from aqueous media using ferrous-form zeolite materials

The present invention is directed to a system and method for converting hazardous speciated and elemental mercury-containing wastes to environmentally acceptable wastes by mixing the wastes in the presence of a polysulfide, water, and an mercury-reactive material, such as elemental sulfur.

Method and apparatus for stabilizing liquid elemental mercury

The present invention is a process for selectively precipitating molybdenum in a form that is substantially free from vanadium impurities. The molybdenum is precipitated in the form of ammonium octamolybdate which has a molybdenum to vanadium ratio of about 400:1 in an initial crystallization and a ratio of about 1300:1 in a subsequent recrystallization.

Process for recovering molybdenum from solution in a form that is

The invention comprises the treatment of metal oxides and mixed metal oxides and metal sulfides in a vertical tube reactor system having a downcomer section and a riser section in order to oxidize and dissolve the metal values in aqueous slurry primarily in the downcomer section and introducing a reducing agent comprising a formate species and reducing the dissolved metal values in the riser section. The reduced metal values are then separated with the gangue values from the product solution downstream from the vertical tube reactor system. The reduced metal values may then be separated from the gangue material by conventional solid separation techniques, such as flotation.

Method of recovering metals from ores using a formate reducing agent

According to the present invention, processes are provided for recovery of nickel, cobalt and like metal values from laterite ores wherein the ores are separated into high and low magnesium containing fractions, the low magnesium fraction is leached with sulfuric acid at elevated temperatures and pressure to solubilize the metal values. The pregnant liquor resulting from the high pressure which also contains solubilized Fe, Al and acid is then contacted with a low magnesium fraction of the ore in a low pressure leach under conditions such that at least some of the acid is neutralized and substantially all of the solubilized Fe and Al is removed as hematite and alunite precipitate. In one embodiment, the pregnant liquor from the high pressure leach and the high magnesium fraction are contacted at atmospheric pressure and a temperature of about 80.degree. C. prior to low pressure leaching. In other embodiments, various process streams are separated by size and otherwise, and recycled to within the processes. In another embodiment, all leached values, including magnesium and sulfuric acid, are recovered, resulting in a dischargeless process which is environmentally and economically acceptable. Elimination of prior art iron and aluminum contaminants by the low pressure leach provides a simplified method of recovery of all elements in the leachate.

Method of recovering nickel from laterite ores

According to the present invention, Ni- and Co-rich, low Mg fines may be advantageously separated from the coarse fractions of lateritic ores by atmospheric or low pressure leaching. In particular, the process of the present invention comprises contacting a lateritic ore or ore fraction at temperatures from about 20.degree. C. to about 200.degree. C. and pressures from about atmospheric to about 200 psig with an aqueous acid solution to form a leach liquor, a leach residue and a fines fraction. The fines fraction which can be separated from the residue with the leach liquor by conventional means such as cycloning is found to be richer in Ni and Co and lower than the remainder of the residue.

Method of liberating nickel- and cobalt-enriched fines from laterite

According to the present invention, improved dissolution of nickel and cobalt and thus improved recovery of those desired metal values is achieved by modifying the ore recovery processes wherein sulfuric acid leaching at elevated temperatures is used to dissolve the nickel and cobalt. In particular, according to the present invention, processes are provided wherein the sulfuric acid and ore are contacted at substantially ambient temperature prior to subsequent heating to attain the elevated temperatures of the sulfuric acid leach. Practice of the present invention has been found to result in improved metal value recovery.

Growing community of inventors

Lakewood, CO, United States of America

John E Litz