Abstract: This disclosure concerns flux-calcined products manufactured from filtration waste streams, and methods for manufacturing the same. In particular, it concerns functional additives produced from spent cake comprising diatomite filtration media which are suitable for use in paints, plastic films and elastomers for control of optical and surface properties, and processes which are suitable for manufacture of such products. It further concerns the recovery of energy from spent cakes during the regeneration process.

Abstract: This invention concerns ultra-high purity, ultra-high performance biogenic silica filtration products comprising diatomaceous earth. In particular, it relates to products comprising diatomaceous earth which is derived from ores that have been specifically selected for their naturally low centrifuged wet density and which have been intensively beneficiated to reduce extractable impurities to near or below detection limits. The low centrifuged wet density of the selected natural ore is either maintained or further reduced through the beneficiation process, which provides for filtration product/media with high particulate holding capacities able to provide for extended filtration cycle times.

Abstract: A diatomite product and method of using such is disclosed. The diatomite product may comprise sodium flux-calcined diatomite, wherein the diatomite product has a crystalline silica content of less than about 1 wt %, and the diatomite product has a permeability between 0.8 darcy and about 30 darcy. In some embodiments, the diatomite product may be in particulate or powdered form. This disclosure also concerns flux-calcined silica products containing low or non-detectable levels of crystalline silica. Some of these products can be further characterized by high permeabilities and a measurable content of opal-C, a hydrated form of silicon dioxide.

Abstract: A method of determining opal-C and cristobalite contents of a product that comprises diatomite is disclosed. The method may comprise performing thermal processing to determine a loss on ignition for a representative first portion of a sample of the product; identifying and quantifying primary and secondary peaks present in a first diffraction pattern that results from bulk powder X-ray Diffraction on a representative second portion of the sample; and using a known standard sample of cristobalite to determine whether the primary and secondary peaks present in the first diffraction pattern indicate the presence of opal-C or cristobalite in the product.

Abstract: This disclosure concerns flux-calcined products manufactured from filtration waste streams, and methods for manufacturing the same. In particular, it concerns functional additives produced from spent cake comprising diatomite filtration media which are suitable for use in paints, plastic films and elastomers for control of optical and surface properties, and processes which are suitable for manufacture of such products. It further concerns the recovery of energy from spent cakes during the regeneration process.

Abstract: This invention concerns ultra-high purity, ultra-high performance biogenic silica filtration products comprising diatomaceous earth. In particular, it relates to products comprising diatomaceous earth which is derived from ores that have been specifically selected for their naturally low centrifuged wet density and which have been intensively beneficiated to reduce extractable impurities to near or below detection limits. The low centrifuged wet density of the selected natural ore is either maintained or further reduced through the beneficiation process, which provides for filtration product/media with high particulate holding capacities able to provide for extended filtration cycle times.

Abstract: A method of determining opal-C and cristobalite contents of a product that comprises diatomite is disclosed. The method may comprise performing thermal processing to determine a loss on ignition for a representative first portion of a sample of the product; identifying and quantifying primary and secondary peaks present in a first diffraction pattern that results from bulk powder X-ray Diffraction on a representative second portion of the sample; and using a known standard sample of cristobalite to determine whether the primary and secondary peaks present in the first diffraction pattern indicate the presence of opal-C or cristobalite in the product.

Abstract: A powdered composite filtration medium includes composite particles that include at least one diatomite particle and at least one expanded perlite particle sintered together. The composite powdered filtration medium may include from about 7 wt % to about 90 wt % diatomite, from about 93 wt % to about 10 wt % expanded perlite. Less than about 1% total crystalline silica may be present in the medium. The medium may have a permeability of at least 0.25 darcy. The diatomite and expanded perlite may be sintered or calcined with or without a fluxing agent.

Abstract: Products (4) comprising a physical component (6) and Silica Documentation (8), and methods of preparing such products (4) are disclosed. In some embodiments, the physical component (6) may be powdered or in particulate form. The physical component (6) includes diatomite. In such products (4), a crystalline silica content of the physical component (6) by weight is greater as measured according to Traditional Methods than as measured according to a method that differentiates between opal-C and cristobalite. The Silica Documentation (8) discloses the crystalline silica content present in the physical component (6) as measured according to the method that differentiates between opal-C and cristobalite. The method of preparing the product (4) may include analyzing the physical component (6) for crystalline silica content using an LH Method to determine cristobalite content and preparing Silica Documentation (8) based on the results of the LH Method.

Abstract: A diatomite product and method of using such is disclosed. The diatomite product may comprise sodium flux-calcined diatomite, wherein the diatomite product has a crystalline silica content of less than about 1 wt %, and the diatomite product has a permeability between 0.8 darcy and about 30 darcy. In some embodiments, the diatomite product may be in particulate or powdered form. This disclosure also concerns flux-calcined silica products containing low or non-detectable levels of crystalline silica. Some of these products can be further characterized by high permeabilities and a measurable content of opal-C, a hydrated form of silicon dioxide.

Abstract: Disclosed is a non-respirable/substantially non-respirable product and method of manufacturing such product. The product may comprise diatomite having a median particle size distribution between about 10 microns and about 60 microns. The product is substantially non-respirable and may be enclosed inside a package wherein the product and inside the package have a combined aerobic bacterial count between about zero and about 114 (CFU/1.0 g). The product may have a dust number less than about 0.2.

Abstract: A powdered composite filtration medium includes composite particles that include at least one diatomite particle and at least one expanded perlite particle sintered together. The composite powdered filtration medium may include from about 7 wt % to about 90 wt % diatomite, from about 93 wt % to about 10 wt % expanded perlite. Less than about 1% total crystalline silica may be present in the medium. The medium may have a permeability of at least 0.25 darcy. The diatomite and expanded perlite may be sintered or calcined with or without a fluxing agent.

Abstract: Low soluble arsenic diatomite filter aids and method of making such filter aids are disclosed. Alumina and/or aluminum hydroxide (ATH) are used as additives when preparing the filter aids, which may be straight-calcined or flux-calcined. Alternatively, activated alumina may be added to an already straight-calcined or flux-calcined diatomite filter aid. As compared to either straight-calcined or soda ash flux-calcined diatomite filter aids of similar permeabilities made from the same ore, the disclosed filter aids have lower soluble arsenic content. The disclosed filter aids have a soluble arsenic content, either by the OIV, EBC or USFCC method, of about 60% or less than the straight or flux-calcined diatomite filter aids of similar permeability without an alumina or ATH additive.

Abstract: Diatomaceous earth products with reduced amounts of cristobalite and higher Y values are disclosed. The diatomaceous earth products are prepared in a conventional manner to produce a flux-calcine diatomaceous earth. The flux-calcine diatomaceous earth is mixed with potassium hydroxide and the mixture is then heated. The combination of the potassium hydroxide and post-calcining heat treatment results in a diatomaceous earth product with reduced amounts of cristobalite and a whiter, brighter appearance.

Abstract: A method of producing a range of diatomaceous earth filter aids having selectable permeabilities and less than about 1 percent by weight total crystalline silica. The method includes milling diatomaceous earth ore to a size range of between about 100 micrometers and about 1400 micrometers; calcining the milled diatomaceous earth in a calciner; and milling the calcined diatomaceous earth in an adjustable milling and classification system to produce diatomaceous earth filter aids. Systems to implement such methods and compositions produced by such methods are also described.

Abstract: A method of producing a range of diatomaceous earth blended filter aids having selectable permeabilities and less than about 1 percent by weight total of crystalline silica and less than about 0.1% by weight total of respirable crystalline silica. The method includes milling diatomaceous earth ore to a size range of between about 100 micrometers and about 1400 micrometers; calcining the milled diatomaceous earth in a calciner; milling the calcined diatomaceous earth in an adjustable milling and classification system to produce diatomaceous earth filter aids, and blending the diatomaceous earth with expanded perlite to form a low bulk density and low solubility filter aid.

Abstract: A method of producing a range of diatomaceous earth filter aids having selectable permeabilities and less than about 1 percent by weight total crystalline silica. The method includes milling diatomaceous earth ore to a size range of between about 100 micrometers and about 1400 micrometers; calcining the milled diatomaceous earth in a calciner; and milling the calcined diatomaceous earth in an adjustable milling and classification system to produce diatomaceous earth filter aids. Systems to implement such methods and compositions produced by such methods are also described.

Abstract: A device (10) for automatically determining filtration parameters for a sample of a filter aid material includes a measurement tube assembly (14) comprising a generally vertical measurement tube (34) and a septum (40) disposed within the tube for forming a filter cake of a filter aid material, a plurality of actuatable valves (V1-V12) coupled to the inlet (32) and discharge (44) of the measurement tube assembly for controlling water flow into and out of the assembly, a control and processor system (17) including a computer (200) operable to control the valves in accordance with a predetermined cycle to flush a slurry of filter aid into the measurement tube assembly and then cause water to flow under pressure through the measurement tube assembly and through a filter cake formed on the septum, and instrumentation (110, 120, 122, 130, 140) for measuring parameters needed for determining filtration parameters.