Бүтээгдэхүүн

  • The Double Face of Metals The Intriguing Case of Chromium

    2021 8 2 Chromium Cr is a common element in the Earth’s crust It may exist in different oxidation states Cr 0 Cr III and Cr VI with Cr III and Cr VI being relatively stable and largely predominant Chromium’s peculiarity is that its behavior relies on its valence state Cr III is a trace element in humans and plays a major role in glucose and fat metabolism.

    одоо эзэмших
  • In situ bioremediation of hexavalent chromium in presence

    Stability of chromium in the ferrochrome slag dumps and leachate are affected by pH redox potential and the presence of other metallic species in the slag It is desirable to keep chromium in slag dumps in the trivalent Cr III state because trivalent chromium is 1000 times less toxic to living organisms than the hexavalent form Cr VI .

    одоо эзэмших
  • Environmental and technical assessment of ferrochrome

    2013 12 1 Chromium is one of the most common toxic heavy metal found in the environment It exists in the common oxidation states of hexavalent chromium Cr VI and trivalent chromium Cr III While chromium as Cr III is less mobile and less harmful Cr VI is highly leachable and extremely toxic under all environmental conditions.

    одоо эзэмших
  • Ferrochrome Slag Trivalent And Hexavalent Chromium

    Hexavalent Chromium present in the slag shall be converted to trivalent chromium Ferrochrome shall be stored in secured landfill as per the CPCB guidelines Bottom ash shall be disposed offin a suitably designed landfill as per CPCB guide line to prevent leaching to the sub oil and underground aquifer.

    одоо эзэмших
  • chemical element chromium Schema Root news

    2021 10 18 Hexavalent chromium is produced as part of the processthat s why they call it a closed furnace Chabot said unless chromium slag is treated it also produces hexavalent chromium He also said residents were not informed about the plant prior to the city naming Coniston as the preferred location for theà Â

    одоо эзэмших
  • Infacon X

    Human Health Risk Assessment for Metallic Chromium and Trivalent Chromium in Accordance with European Union Legislation M Luotamo and V Riihim„ki Hexavalent Chromium Air Dispersion Modelling in the South African Ferrochromium Industry L.W Burger SILICON Session Chairpersons J Brosnan

    одоо эзэмших
  • PDF

    Clean Air Journal

    2.1.1 Dry dumping to slag dumps Dust was transpofted pneumatically or at other plants by means of chain or scraper conveyor to a silo from where it was loaded onto trucks and transported to a slag dump Water sprays were used to prevent dust nuisance 2.12 Pelletising and dumping on slag dumps .

    одоо эзэмших
  • PDF

    Health Consultation

    2006 2 28 From 1952 to 1980 Chromium Mining and Smelting Corporation produced alloys of ferrochrome ferrosilicon and ferromanganese Chromasco used coke gravel chrome ore and manganese ore as principal raw materials Although furnace operations ceased in 1980 from 1981 to 1983 the plant operated as a ferrochrome slag concentrator.

    одоо эзэмших
  • Minerals

    Furthermore the trivalent state of chromium in sulfate could be easily oxidized to the toxic hexavalent state making the residue become a potential source of chromium contamination Therefore these sulfate phases should be prevented from precipitating by controlling processing parameters or recovered via some specific methods.

    одоо эзэмших
  • Chromium accumulation and toxicity in aquatic vascular

    2004 7 1 It occurs in several oxidation states ranging from Cr p.2 to Cr p.6 with trivalent and hexavalent states being the most stable and common in terrestrial environments Zayed et al 1998 The average concentration of chromium in nonpolluted soils is ca 100 mg/kg whereas contaminated soils may contain up to 7000 mg/kg.

    одоо эзэмших
  • PDF

    MEDICAL EVALUATION OF CHILDREN AND ADULTS OF

    2016 9 20 The two chemical types of chromium of most interest are trivalent and hexavalent which occur in a variety of chemical compounds Serious health effects are linked to exposure to hexavalent chromium compounds 12 Some chromium compounds are strong irritants and can cause damage to skin and breathing passages Damage may occur to the

    одоо эзэмших
  • principal ore of chromium

    principal ore of chromium randpic Core Principles The Chromium Projects Core Principles These are the things that are important to us these principles shape the product that we build Note that the examples given are meant to be illustrative rather than exhaustive Spee

    одоо эзэмших
  • Reviews of the Environmental Effects of Pollutants III

    Both hexavalent and trivalent chromium are taken up by aquatic organisms Section 5.2.1 Trivalent chromium in waters is often in particulate form and can be ingested therefore it is found in the digestive tract of bottom dwellers Hexavalent chromium compounds are soluble and can be rapidly sorbed by the gut and body walls.

    одоо эзэмших
  • Chromium cycling in soils and water links gaps and

    1991 5 1 HORI M SHOZUGAWA K and MATSUO M 2017 Relevance of Hexavalent Chromium Seepage to Rainfall at Chromium Slag Dumping Site in Tokyo クロムからの6クロムととの Journal of Environmental Chemistry 10.5985/jec.27.129 27 4 129 135 Online publication date 18 Dec 2017.

    одоо эзэмших
  • Composition and properties of the main types of

    2006 5 18 The results of an integrated study of high alumina slag generated in the production of ferrotitanium ferrochrome and metallic chromium by the aluminothermic method at the Kluchi FerroalloyWorks are described The chemical and mineral composition and refractoriness of the main varieties of slag are identified The prospects for application of refractory slag are considered.

    одоо эзэмших
  • PDF

    TABLE OF CONTENTS

    2010 1 5 Human Health Risk Assessment for Metallic Chromium and Trivalent Chromium in Accordance with European Union Legislation M Luotamo and V Riihimäki Hexavalent Chromium Air Dispersion Modelling in the South African Ferrochromium Industry L.W Burger SILICON Session Chairpersons J Brosnan J P Bucher

    одоо эзэмших
  • chemical element chromium Schema Root news

    2021 10 18 Hexavalent chromium is produced as part of the processthat s why they call it a closed furnace Chabot said unless chromium slag is treated it also produces hexavalent chromium He also said residents were not informed about the plant prior to the city naming Coniston as the preferred location for theà Â

    одоо эзэмших
  • Use of selected industrial waste materials in concrete

    2011 9 13 Chromium leaching from deposited sites is of high environmental relevance associated with the contamination of natural resources with toxic hexavalent chromium Cr 6 In the environment Cr occurs in two oxidation states Cr 6 such as chromate and bichromate CrO HCrO and trivalent chromium Cr 3 .

    одоо эзэмших
  • Chrome Processing And Drying

    Chrome Processing And Drying Chrome processing and drying Equipment Acid resisting rubber stainless steel or plastic buckets troughs or other suitable containers should be used to hold thechromite ore drying amp grinding systemChomite ore processing plants CDE Asia Chromite ore is predominantly used in the production of ferrochrome an alloy of chrome and iron.Spray Drying Anderson

    одоо эзэмших
  • Hexavalent chromium in the recovery of ferrochromium

    1997 10 1 Hexavalent Cr is highly mobile carcinogenic and toxic Bartlet 7 has proposed a number of chemical methods for characterizing environmental chromium in soils The products generated in the jigging operation were investigated by these methods to assess to what extent Cr III can be mobilized and oxidized or Cr VI can be reduced in the

    одоо эзэмших
  • Cancer incidence among Finnish ferrochromium and

    2013 11 19 The chromium content of the dust was 1–5 which indicates that the median personal exposure to chromium was 22 µg/m 3 Cr 6 was not detected in any of the samples from the mine 5 In the furnace department of the ferrochromium smelter the median personal dust exposure was 1.5 mg/m 3 The median chromium concentration was 143 µg/m 3.

    одоо эзэмших
  • SciELO

    The response variable or chromium conversion Y was obtained from determinations of the Cr 2 O 3 concentration in the slag phase and the slag mass value The slag mass was determined by the total mass balance which is the difference of the initial charge mass and the alloy and volatilised masses.

    одоо эзэмших
  • PDF

    A review on the existence of chrome in cement and

    2012 8 4 chromium is by eating foods that contain chromium and trivalent chromium is identified as a natural essential nutrient for humans in many fresh vegetables fruits grain meat and yeast 50 200µg/d has been identified as an estimated safe and adequate daily dietary intake However hexavalent chromium is more easily absorbed by the body than

    одоо эзэмших
  • Ferroalloys

    Chromium alloys In D I Mendeleev’s periodic table of chemical elements chromium is in d block group 6 period 4 and has atomic number 24 Its symbol is Cr derived from the Latin word chromium Chromium in its elementary form CAS number 7440 47 3 is a solid bluish white metal Occurrence Chromium is an abundant element 0.02 wt .

    одоо эзэмших
  • PDF

    Potential Toxic Effects of Chromium Chromite Mining

    2019 10 11 Smelting also produces Cr VI contaminated slag with estimated total chromium contents of 2 to 12 The discovery that dry pulverizing of slag and ore converts Cr III to Cr VI may be very important during steps such as ferrochrome recovery from slag and end uses of crushed slag.

    одоо эзэмших
  • PDF

    Hexavalent chromium removal by ferrochromium slag

    Journal of Hazardous Materials B126 2005 176–182 Hexavalent chromium removal by ferrochromium slag Mehmet Erdema H Soner Altundogan˘ b M Deniz Turanb Fikret Tumen¨ b ∗ a Department of

    одоо эзэмших
  • One hundred years of chromium and cancer A review of

    M M Hiller R W Leggett A biokinetic model for trivalent or hexavalent chromium in adult humans Journal of Radiological Protection 10.1088/1361 6498/ab4286 40 1 19 39 2019 Crossref

    одоо эзэмших
  • PDF

    Unsafe Chromium and its Environmental Health Effects of

    2010 4 13 dumping sites For example hexavalent chromium content in certain parts of orissa has been found to be 550 1500 ppm mg/l in well water 25 100 ppm in irrigation reservoirs and 4000 ppm mg/l in the soil making it unfit for domestic usages 23 Trivalent chromium Cr VI is considered an essential micronutrient for physiological activity.

    одоо эзэмших
  • One hundred years of chromium and cancer A review of

    M M Hiller R W Leggett A biokinetic model for trivalent or hexavalent chromium in adult humans Journal of Radiological Protection 10.1088/1361 6498/ab4286 40 1 19 39 2019 Crossref

    одоо эзэмших