Vermiculite (Verm) is a generally ctahedral 2:1 clay mineral with hydrated cations occupying the interlayer space. However, the negative layer charge of Verm, arising mostly from substitution of Al 3 + for Si 4 + in tetrahedral sites, is larger than that of smectite (Brigatti et al., 2013). Haley et al. (1982) observed two sharp Raman bands at 3739 cm − …
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Modeling community asbestos exposure near a vermiculite processing facility: impact of human activities on cumulative exposure. ... Accepted: 24 February 2014. Published: 23 April 2014. Issue Date ...
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Between the 1920s and 1990s, vermiculite mined from Libby (estimated in the millions of tons) was shipped by railroad to 245 facilities within the US for processing via exfoliation [13]. Exfoliation refers to a commercial pro- cess where vermiculite is rapidly heated to expand it into low-density, accordion-like nuggets [13]. At the facili-
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Exposure to Asbestos-Containing Vermiculite from Libby, Montana, at 28 Processing Sites in the United States . October 29, 2008 . Photographer: Unknown . Prepared by U.S. Department of Health and Human Services Agency for Toxic Substances and Disease Registry Division of Health Assessment and Consultation
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Vermiculite is a hydrated magnesium-aluminum-iron silicate. ... This expansion process is called exfoliation, and the resulting ultralightweight aggregate is chemically inert, ... 2012; Torrisi and Patel, 2014). Near Brasilia in Catalao, Goias State, Brasil Minérios owned the mining rights to vermiculite deposits containing estimated
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Vermiculite processing results The target of the system design was to obtain exfoliated vermiculite within the bulk density standards (see Table 1 ), as …
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During processing, the rock is rapidly heated to about 900 degrees Celsius causing the water to vaporize and creating countless tiny bubbles in the heat-softened glassy particles. The resulting material is the familiar white perlite, extremely light in weight, since it has expanded 4 to 20 times its original volume." ... "In primary usage ...
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When Libby vermiculite was being processed at the Glendale plant between 1951 and 1964, and the Phoenix plant between 1964 and 1992, dust and fibers might have been released into the air. ... The Glendale plant closed in 1964 and the Phoenix plant stopped processing Libby vermiculite in 1992. The public health consultations for the …
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. The purpose of this ... Residents of the surrounding community also had direct contact with vermiculite processing wastes (containing up to 10% amphibole asbestos) that were made freely available. Children played on waste piles and neighborhood residents hauled the wastes away for home use. In total, 259 …
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Vermiculite is a natural and non-toxic 2:1 silicate clay mineral with strong cationic exchange capacity and adsorption properties. Therefore, it can be used as a soil amendment to loosen soil and promote crop growth. In addition, vermiculite has the advantages of low cost and environmental friendliness. The biomass raw material for
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Section snippets Experimental. The vermiculite used in this work has the approximate composition (Al 0.30 Ti 0.04 Fe 0.63 Mg 2.00)(Si 3.21 Al 0.79)O 10 (OH) 2 Mg 0.13 Na 0.02 K 0.10 (H 2 O) n.The exfoliation was carried out by introducing the vermiculite in a quartz tube at 1000 °C for 60 s.The exfoliated vermiculite was impregnated with …
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One of the most common health hazards in processing vermiculite comes from quartz, which is crystalline silica. It is usually only present as larger particles, but when it is ground into finer particles, the dust can be …
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Abstract This paper reports on the application of process mineralogy to understand the experimental performance of a microwave based system for the …
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is a process flow diagram for vermiculite processing. Crude ore from open-pit mines is brought to the mill by truck and loaded onto outdoor stockpiles. Primary processing consists of screening the raw material to remove the waste rock greater than 1.6 centimeters (cm) (5/8 inch [in.]) and returning the raw ore to other stockpiles.
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vermiculite waste piles frequen tly had twice the risk of pleural abnormalities compared with those who never played in the piles (OR ¼2.02, 95% CI, 1.59–2.57), and subjects exposed
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These grades are set by The Vermiculite Association (The Vermiculite Association, 2014). The medium grade samples were sourced from Brazil and China, while the superfine grade samples were from Australia and South Africa. ... Vermiculite processing results. The target of the system design was to obtain exfoliated vermiculite …
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The adsorption on expanded vermiculite revealed to be an efficient process to recovery neodymium. • Langmuir represented the equilibrium of adsorption. • The expanded vermiculite achieved a maximum adsorption capacity of 0.48 mmol/g at 283 K. • The process was exothermic, spontaneous, and reversible; •
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vermiculite. The Vermiculite Association (TVA) does not guarantee the accuracy of information contained in this booklet. Control Measures and Personal Protective Equipment Like all materials, vermiculite can be subject to control measures with regard to its handling, use in processing, transportation, end use and possible disposal.
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South Africa Vermiculite Processing Plant. According to different production requirements, product specifications of vermiculite are as follows:8-12MM,4-8MM,2-4MM,1-2MM,0.3-1MM,40-60 mesh,60-80 mesh,80-100 mesh, 100 mesh, 150 mesh, 200 mesh, 325 mesh, etc. With the development of vermiculite's applications, South African abundant ...
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The 2013-2014 Northeast Minneapolis Community Vermiculite Health Study assessed asbestos-related cancer incidence and death to determine if there was more asbestos-related disease than expected, based on the general Minnesota population. ... The findings suggest that past exposure to asbestos from the vermiculite processing plant may have ...
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vermiculite waste piles frequen tly had twice the risk of pleural abnormalities compared with those who never played in the piles (OR ¼2.02, 95% CI, 1.59–2.57), and subjects exposed
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The present invention proposes a kind of vermiculite production and processing technology, its method steps is as follows: pulverized by vermiculite raw material; Vermiculite raw material after pulverizing is crossed screen sizing; Vermiculite raw material after once sieving is carried out a removal of impurities through sand removing …
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INTRODUCTION Vermiculite is the geological name given to a large group of hydrated laminar, or layered, minerals that are aluminum-iron magnesium silicates that resemble mica in
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Animal slurry storage is an important source of NH 3 emission which has raised a high attention regarding its influence on air quality and environment health. There is an urgent need to develop an efficient, green and safe technology for reducing NH 3 emission. This study introduced a novel method of reducing NH 3 emission from dairy …
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brick processing or vermiculite processing at this time because no documents have been found, and silos were used at other exfoliation sites to store raw vermiculite) [3, 4]. During the time that this property was used by the W. R. Grace Zonolite Company, there was a warehouse, shed, loading dock, and the four silos on the property [4].
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Ore from the Libby mine was shipped to many processing plants around the country. From 1938 to 1989, ore was processed at the Western Mineral Products plant located at 1720 Madison St. NE in Minneapolis. At this plant, raw vermiculite was heated until the moisture trapped in the ore caused it to pop like popcorn.
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Vermiculite processing machine Country Status (1) Country Link; US (1) US2203821A (en) Cited By (14) * Cited by examiner, † Cited by third party; Publication number Priority date Publication date Assignee Title; US2572484A (en) * : : Howle: Apparatus for expanding perlite and the like ...
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Zonolite is a highly toxic vermiculite insulation product mixed with asbestos that was produced from the 1940s umtil the 1990s. The plant exfoliated vermiculite from its construction in 1953, through its purchase by W.R. Grace & Co. In 1964, until 1989. Before 1964, there is no information on who owned the building.
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Vermiculite Mining and Processing. South Carolina is the largest producer of vermiculite in the United States, which poses a threat to state residents. Although the mineral is not dangerous, vermiculite ore often contains large amounts of asbestos. People who worked at or lived near vermiculite mines or vermiculite processing facilities may ...
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2.4 acres of land, although vermiculite has been identified beyond the facility boundaries. This removal assessment addresses the need to iden-tify and mitigate the potential threats posed by asbes-tos contaminated soils located on-site from the processing of vermiculite ore and the disposal of as-sociated waste products at this Site by W.R.
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Over a 70-year period, a mine near Libby, MT supplied nearly 80% of the world's vermiculite. Raw vermiculite, which was contaminated with naturally occurring amphibole in veins throughout the deposit, was shipped to processing sites throughout the United States for exfoliation. In this pilot study, tree bark samples were collected near …
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Sites related to asbestos from buildings or other processed asbestos products (by state) Sites related to Libby, Montana vermiculite mining and processing. ATSDR has been …
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Radiographic evidence of nonoccupational asbestos exposure from processing Libby vermiculite in Minneapolis, Minnesota. Bruce H. Alexander, Katherine K. Raleigh, Jean E Johnson, Jeffrey H. Mandel, John L. Adgate, Gurumurthy Ramachandran, Rita B. Messing, Tannie Eshenaur, Allan N Williams
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PROCESS FOR PRODUCING HIGHLY EXFOLIATED VERMICULITE DOES NOT REQUIRE THE USE OF ORGANIC BINDING OR ORGANIC ADDITIVE TO BE SHAPED GB2503937A (en) * : : Goodwin Plc: Chemically and thermally exfoliated vermiculite fire resistant spray paint EP3483484A1 (en) * : 2019 …
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Asbestos Exposure Near W.R. Grace Vermiculite Processing Plant in North Little Rock Dixie Neighborhood. W.R. Grace maintained a vermiculite processing plant in North Little Rock from 1953 to 1989. Vermiculite is a mineral that is often contaminated with asbestos. In 2011, the Environmental Protection Agency (EPA) found traces of asbestos …
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These other North Carolina-based vermiculite processing facilities included the Southern Vermiculite Plant in Franklin County, Carolina Wholesale in Sanford and the American Vermiculite Company …
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