Producer of natural zeolites for consumer and industrial use
1212 N. Washington
Suite
132 Spokane, WA 99201
(509) 328-5685
(800) 367-1534
(509) 328-3706 Fax
Email:
info@steelheadspecialtyminerals.com
Steelhead Specialty Minerals
Producer of natural zeolites for consumer and industrial use
1212 N. Washington Suite
132 Spokane, WA 99201
(509) 328-5685
(800) 367-1534
(509) 328-3706 Fax
Email:
info@steelheadspecialtyminerals.com
Here are a few topics of interest: you may click on a choice that interests
you or scroll down for more information.
Introduction and Background
Sewer and Wastewater Treatment
Metals Removal
Radioactive Waste Treatment
Sorbent Barriers
Air Filtration
Aquaculture
Agriculture
Fillers
Gas Separation and Purification
Heat Storage and Solar Refrigeration
Modified Natural Zeolites
System Engineering
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Industrial Applications for Zeolites
Natural zeolites are the least-known treasures for environmental pollution control, separation science and technology. Natural zeolites are volcanic minerals with unique characteristics. Their chemical structure classifies them as hydrated aluminosilicates, comprised of hydrogen, oxygen, aluminum, and silicon, arranged in an interconnecting lattice structure. The arrangement of these elements in a zeolite crystal gives rise to a honeycomb framework with consistent diameter connecting channels that vary in size from 2.5 to 5.0 angstroms, depending on the type of zeolite mineral. This unique structure makes zeolites different from "other" aluminosilicates (kaolin, bentonite, etc.) due to the following special properties:
• Gas adsorption: the ability to selectively adsorb molecules of gases and vapors;
• Water absorption/desorption: the ability to reversibly absorb/desorb water without any chemical or physical
change in the zeolite matrix;
• Ion exchange: the ability to exchange inherent cations for other cations on a basis of ion selectivity.
Steelhead Specialty Minerals, in association with VeeTech Engineering has pioneered numerous beneficial applications for natural zeolites. The applications are in the form of development, demonstration and development of engineered systems that result in huge savings in capitol and operating costs. A few examples of the beneficial applications are as follows:
SEWAGE AND WASTEWATER TREATMENT
Ammonia is a major issue for the treatment of municipal wastewater. Ammonia levels in municipal wastewaters can be reduced to 10-15 ppm through traditional primary and secondary treatment facilities. Final circulation in the tertiary treatment stage is accomplished with polishing filters containing clinoptilolite, a popular form of natural zeolite. The zeolites lower the level of ammonium to non-toxic, acceptable levels. The zeolite beds can be regenerated and recycled indefinitely.
Significant properties include:
• High cation exchange capacity
• Selectivity for ammonium cations
• Regeneration capability
The size of zeolite used in wastewater polishing filter columns varies according to the design. A size specification of -20 to +35 Tyler mesh is typical for this application.
METALS REMOVAL - MINE WASTEWATER TREATMENT
Zeolites are highly selective scavengers of a variety of metal cations that can be removed from liquid effluents through the process of ion-exchange. These cations include lead, silver, cadmium, cobalt, zinc, copper, mercury, magnesium, iron, aluminum, chromium and others. Clinoptilolite water polishing treatment systems are applicable in industries such as mining, electroplating and electronics. Giant industrial houses, like IBM, have deployed this application for treatment of wastewater containing heavy metals.
Significant properties include:
• High cation exchange capacity
• Selectivity for many metals
• Low cost relative to resins or synthetic zeolites
• Capacity for regeneration
Specifications are highly variable according to the end use. Pilot-scale studies are recommended to determine the appropriate zeolite product for a site specific waste stream.
Process effluents bearing radioactive isotopes can be treated through columns packed with natural zeolites. The zeolites selectively remove cesium (Cs134, CS137) and Strontium (Sr90) isotopes through the process of ion-exchange. Effluent liquids are purified to acceptable limits for discharge as the radioactive isotopes are held within the zeolite cage structure. One outstanding example of the application is the British Nuclear Fuels, Ltd. Site Ion Exchange Efficient Plant (SIXEO) at Sellifield, England. The other large application is for the treatment of low level liquid effluents at the DOE West Valley, NY site, where Phillipsite was used to selectively remove CS137 and SR90 isotopes. The permanent storage or disposal of the waste is facilitated by the inorganic and stable structure of the zeolite which can be encapsulated in cement or glass.
Significant properties of zeolite in this application include the following:
• High cation exchange capacity
• Selectivity for cesium and strontium
• Radiation Stability
• Resistance to mechanical attrition
• Cost Effective relative to other methods
These zeolites are produced with the high quality assurances. A size specification in the range of 20 by 50 Tyler mesh has been cited as optimal. The most common Steelhead Specialty Minerals zeolites in service today include TSM 140 (clinoptilolite), TSM 180 (Phillipsite) and TSM 300 (Chabazite). The decontamination factors achieved by these products often exceed expectations.
SORBENT BARRIERS FOR RADIOACTIVE WASTE
Permeable barriers incorporate sorbent materials, including zeolite, to selectively contain contaminants that are percolating from shallow land burial sites of low-level radioactive waste. The zeolites are combined with clays and other materials that retard the migration of leachate for a period long enough to allow exchange and/or decay of radioactive ions.
Beneficial qualities include:
• High cation exchange capacity
• Low cost
• Large tonnage reserves
Finely crushed zeolites are used in sorbent barrier layers. Exact specifications are dependent upon the engineered permeability of the system.
Natural zeolites are an adsorbent of choice for many cost effective air pollution control technologies treating the hazardous air pollutants (HAP) and listed volatile organic compounds (VOC). The need for technologically improved air purification systems has been indicated by keen client interest in the use of zeolites in controlling indoor air pollutants or "sick building syndrome". Existing filtration systems typically contain activated carbon as the adsorbent media. Because most grades of activated carbon contain large internal pores, they tend to trap a wide variety of larger molecules. Zeolites, on the other hand, contain a very small internal pores, in all cases from 3 to 5 angstroms. For this reason zeolite is a highly selective adsorbent of specific gas-phase molecules and elements. Many of the identified indoor air pollutants, including formaldehyde, chloroform, ammonia and carbon monoxide, are in a size range that is most effectively sieved by zeolite. Many promising zeolite and zeolite/carbon air purification and odor controlling systems are being developed to meet the need.
Beneficial qualities include:
• Selectivity for pollutant gases of concern
• Inexpensive relative to other molecular sieves
Clinoptilolite is used to control ammonium in filtration systems at many commercial fish farms, in home aquarium products and during fish transportation. The zeolite has the double benefit of performing both chemical filtration by ion exchange while serving as a biological filtration substrate. As a bio-filter, the loaded zeolite provides a concentrated source of ammonium upon which reducing bacteria may feed.
Significant properties include:
• High capacity and selectivity for ammonium
• Resistance to attrition
• Easily recharged
Clinoptilolite is used in various particle sizes ranging from 1 1/2" x 3/4" to -14x40. generally utilized in -4 to +20 standard mesh whether it be in filter columns for commercial fish farms or within numerous repackaged products for home aquarium filters. Finer-ground products are used in some aquacultural systems.
High potassium clinoptilolite is recognized as an excellent field soil amendment. Steelhead Specialty Mineral's clinoptilolite products TSM 150, CS 400 and TSM 110 carry potassium as the major exchangeable cation. In direct soil application, the clinoptilolite provides a source of slowly released potassium. If previously loaded with ammonium, the zeolites can serve a similar function in the slow release of nitrogen. The potential for hi-tech or specialty potting soil formulations is evident. Cuban studies in the emerging field of "zeoponics" suggest that some crops may be grown in 100% zeolite or zeolite mixtures in which the zeolite is previously loaded or coated with fertilizer and micronutrients.
Benefits include:
• Slow-release mechanism
• Ability to be loaded with fertilizers
• Exchange and release of inherent potassium
• Low cost
• Increasing use for golf course greens top dressing
• Hydrophillic
• Increased yields documented for many crops
PHYTOREMEDIATION
Phytoremediation is a process for uptaking heavy metals by certain plant roots and leafs. Natural zeolites can increase the rate of phytoremediation for certain metals, and isotopes.
Zeolites are used extensively in Japan as fillers in the manufacture of paper. These filler grades of zeolite have a large potential for utilization in the paint and plastics industries. Many deposits of natural zeolites contain high-brightness reserves and the potential for benefaction is increasing with improved technology for magnetic separation and bleaching of zeolite.
GAS PURIFICATION AND SEPARATION
Because zeolites possess the ability to act as molecular sieves, they are used to purify or sweeten natural gases through the removal of impurities such as carbon dioxide, sulfur dioxide and water. In addition to upgrading natural gas, zeolites are used to separate oxygen and nitrogen in pressure swing adsorption columns. These utilizations of natural zeolites are most common in Japan, as most domestic gas purification and separation is done with high-cost synthetic zeolite molecular sieves.
HEAT STORAGE AND SOLAR REFRIGERATION
The high heat of adsorption and ability to hydrate and dehydrate while maintaining structural stability have been found to be useful in various heat storage and solar refrigeration systems. A hydroscopic nature coupled with an inherent exothermic reaction when taken from a dehydrated to a hydrated form (heat of adsorption), make natural zeolites effective in the storage of solar and waste heat energy.
A variety of products have been formulated wherein zeolites are pelletized and/or activated for utilization in specific applications. Some of these products include:
• Manganese coated zeolites used in home water softening and purification units
• Air dryers for compressed air brake systems
• Insulated window desiccants
• General packaging and food desiccants
• Moisture absorbents in automotive mufflers
• Moisture absorbents in refrigeration systems
FOR MORE INFORMATION . . .
The previous description of natural zeolites begins to outline the tremendous potential of this unique mineral. There are other uses not listed here which further utilize the benefits of this material's unusual mix of properties. The cost effectiveness of natural zeolites in retrofit designs and newly developed systems will push them to the forefront of state of the art technologies. For just pennies per pound, this product can be applied in a variety of uses ranging from single low tech systems to intricate high tech designs.
To better understand some of the diversified applications of natural zeolites call us at (800) 367-1534 (U.S. and Canada) or (509) 328-5685. You may wish to refer to some of the following Data Sheets:
• 202 Agriculture
• 203 Odor Control
• 204 Heat Storage & Solar Refrigeration
• 205 Aquaculture
• 206 Gas Separation
• 207 Water Treatment
The above links summarize information available. For a copy of the actual Data Sheet please contact us.