Transport of hexavalent chromium in the vadose zone by …
Column tests were conducted to evaluate the transport of Cr from underlying chromium ore processing residue (COPR) through the vadose zone in capped and uncapped scenarios and to determine if an asphalt cover system is a viable containment strategy. Four large (140 mm diameter) columns and one small (50 mm diameter) column were filled with COPR …
اقرأ أكثر
Chromium processing
Chromium processing. Most of the world's production of chromite (95%) is used in the metallurgical industry in the form of ferrochromium alloys. ... higher chromium ore flotation recoveries, deliberate changes in the charge composition are reflected rapidly in the slag or metal, and closed top operation allows furnace off-gas energy to be used
اقرأ أكثر
TuXingSun Mining
TuXingSun Mining provides state-of-the-art mining and mineral processing equipment for metallic and non-metallic minerals. We offer comprehensive services including ore testing laboratories, global ore trade, and turnkey mining technology solutions. Our global expertise ensures efficient and sustainable mining operations for gold, copper, rare earths, and other …
اقرأ أكثر
Cost-effective strategy of treating chromite ore processing …
23. US DOE. Chromium Treatment Technology Information Exchange for Remediation of Chromium in Groundwater at the Department of Energy Hanford Site. SGW-38255. 2009. 24. Li Y, Liang J, Yang Z, et al. Reduction and immobilization of hexavalent chromium in chromite ore processing residue using amorphous FeS2.
اقرأ أكثر
What Equipment Is Needed for Chromium Ore Processing
The Introduction of Chrome Ore Processing Plant. For its high strength, high temperature resistance, wear resistance, corrosion resistance, oxidation resistance and other characteristics, chromium metal is widely used as an indispensable main materials in metallurgical industry, military, aviation, automobile, national defense, shipbuilding and other …
اقرأ أكثر
Chromium processing | Extraction, Uses & Applications
Chromite deposits are mined by both underground and surface techniques. Much of the ore is rich enough to be used directly: for …
اقرأ أكثر
Chrome ore beneficiation challenges
This article reviews the major process flow sheets in practice for the recovery of chromite values from various types of ores and critical issues related to chromite ore beneficiation.
اقرأ أكثر
Chrome ore beneficiation challenges & opportunities – A …
Supply of world chromite (chrome ore) has come under severe pressure over the past year driven by strong demand for ferrochrome used in ferroalloy production for making …
اقرأ أكثر
Optimisation of metal extraction from chromium ore processing …
The feasibility of extracting metals from chromium (Cr) ore processing residue (COPR) was investigated. COPR samples collected from four sites in New Jersey, USA (sites A, B, C and D) were mixed with 15% carbon by weight with different percentages of sand to neutralise the basic oxide in COPR and heated under a reducing environment to extract metals.
اقرأ أكثر
Jersey City Chromium Cleanup
From the 1900s until the 1970s, a chrome manufacturing by-product called chrome ore processing residue was used as fill in parts of Jersey City, including the Route 440 properties. The remediation also addressed non-chromium contaminants, primarily lead, that are likely associated with other fill soils used at the site.
اقرأ أكثر
Conversion of Chromium Ore Processing Residue to …
to hexavalent chromium. The highly soluble hexavalent chromium was then removed from the COPR (left over Chromium Ore Processing Residue) leaving un-oxidized trivalent chromium and slow-dissolving hexavalent chromium compounds [Burke et al., 1991]. In the absence of information on the toxicity of hexavalent chromium, COPR was subsequently used ...
اقرأ أكثر
Water/acid/reductive biomass leaching of Cr(VI) in chromium ore …
1. Introduction. Chromium ore processing residue (COPR) is the solid waste obtained from the production of chromium metal and chromium salt, mainly from the process of preparing sodium dichromate by calcium roasting method (Li et al., 2019; Senko et al., 2014; Zhang et al., 2009).For every 1 t of chromium salt and metal, 2–3 t and 7–10 t of COPR, …
اقرأ أكثر
Hudson County Chromate Chemical Production Waste Sites
NJDEP has identified over 160 sites that are contaminated with chromite ore processing residue, also known as chromate waste. ... public meeting to discuss the DEP-PPG-Jersey City Settlement Agreement regarding remediation of chromium-contaminated sites. The public meeting will be held Monday, March 30, 2009 at 7:00 p.m at City Hall, located on ...
اقرأ أكثر
Professional Chromium Processing Solutions
In the chromium mining process, the classification stage classifies the finely crushed materials according to the ore particle size, separates particles of different sizes, and effectively screens out oversized or undersized particles in the chromium mining process, ensuring that the appropriate particle size enters the mineral processing process.
اقرأ أكثر
Treatment of soda ash chromite ore processing residue by …
In the industrial production of chromium and chromate, a large amount of Chromium Ore Processing Residue (COPR) is produced (Antony et al., 2013).COPR contains a lot of soluble hexavalent chromium Cr(VI) with high fluidity, high oxidation state, and high toxicity, which seriously threatens human life and health (Suljevic et al., 2021; VonHandorf et al., 2021).
اقرأ أكثر
Stabilization of chromium ore processing residue (COPR) …
Chromium has been classified as a potential carcinogen [8], and has high and acute toxicity to humans, animals, plants, and microorganisms. Consequently, chromium contaminant in groundwater, chromium ore processing residue (COPR), and sediment represents a significant environmental and public health concern [9].
اقرأ أكثر
Remediation of lime-free roasting chromite ore processing residue …
Remediation process and utilization treatment of chromite ore processing residue (COPR) is an environmental issue which is not solved completely. Based on the characteristics of industrial lime-free COPR, a two-step treatment procedure including water leaching and biomass pyrolysis was proposed in this study.
اقرأ أكثر
A detoxification and value-added process for chromium ore …
Chromium ore processing residue (COPR), containing much virulent hexavalent chromium [Cr(VI)], is a by-product derived from chromate production. Fe-C-bearing dust from …
اقرأ أكثر
Chromium Statistics and Information | U.S. Geological Survey …
Chromium (Cr) has a wide range of uses in metals, chemicals, and refractories. It is one of the Nation's most important strategic and critical materials. Chromium use in iron, steel, and …
اقرأ أكثر
Effective Cr(VI) reduction and immobilization in chromite ore
Chromite ore processing residue (COPR) is a typical hazardous waste produced during the manufacture of chromium salt. It is estimated that the total amount of COPR is more than three million tons in China, and the annual increase is approximately sixty thousand tons ( Sun et al., 2014 ).
اقرأ أكثر
Efficient reduction of Cr(VI) and recovery of Fe from chromite ore …
Chromite ore processing residue (COPR) is a by-product generated after the leaching of sodium chromate by roasting chromite ore at 1200 °C. However, the residual 1130–8500 mg/kg of highly ... Reduction and immobilization of hexavalent chromium in chromite ore processing residue using amorphous FeS2. Sci. Total Environ., 658 (2019), pp. 315-323.
اقرأ أكثر
Immobilization of chromite ore processing residue with alkali-activated
Chromite ore processing residue (COPR) is an industrial solid waste [1].It has been reported that 2–3 t of COPR is generated in the production of 1 t chromic salts [2].Accumulation of COPR takes up considerable land, and when the leached hexavalent chromium flows into the water after rainfall, it pollutes the water and the soil and harms …
اقرأ أكثر
Top 3 Chrome Ore Processing Methods that Get Higher …
Ftmmachinery can design a reasonable chrome ore beneficiation process according to the customer's situation and provide a complete set of chrome ore processing …
اقرأ أكثر
LED-driven photocatalytic degradation of tetracycline by chromite ore
Soda-based chromite ore processing residue (COPR) is a hazardous waste produced from chromium salt plants. In this study, detoxified water-washed chromite ore processing residue (DW-COPR) was investigated as a catalyst to activate peroxymonosulfate (PMS) to degrade tetracycline (TC) in the presence of visible light.
اقرأ أكثر
Chrome ore beneficiation challenges & opportunities – A …
Chromium ore occurs exclusively in rocks formed by the intrusion and solidification of molten lava or magma which is very rich in the heavy, iron containing minerals such as pyroxenes and olivines. The chromium spinel is a heavy mineral and it concentrates through gravity separation from most of the other molten material in the magma during ...
اقرأ أكثر
Donskoy Ore Mining and Processing Plant
Ore with a high chromium oxide content (up to 62% Cr 2 O 3) is used to produce ferroalloys in metallurgy, as well refractory products, and chromium compounds in the chemical industry. The Donskoy Ore Mining and Processing Plant employs a total of 7,500 people across 27 structural units. Five of them are core operations producing commercial ...
اقرأ أكثر
Sufficient extraction of Cr from chromium ore processing …
Chromium ore processing residue (COPR) is a hazardous waste generated during the production of chromate. Currently, approximately 10% of Cr 2 O 3 cannot be extracted after chromite sodium roasting and remains in COPR, wasting valuable Cr resources. In this study, Mg was selectively removed by using (NH 4) 2 SO 4 roasting in combination with H 2 …
اقرأ أكثر
A detoxification and value-added process for chromium ore processing
Chromite ore processing residue (COPR) is a byproduct produced in chromite processing at high temperature (1000–1200 °C). 2.5–3 tons of lime-based COPR were generated per ton of chromium salt (calculated by Na 2 CrO 4) (Fu et al., 2021).Although soda roasting (less than 0.8 tons of COPR per ton of sodium dichromate) has been used to …
اقرأ أكثر
Extraction of Chromium from Chromite Ore
Chromite Ore Processing. Low-grade ore obtained from an open cut trench at a chromite deposit near Auburn, ... Chromium Ore Metallurgy. Two samples of ore containing about 6 pct Cr2O3 were obtained from a core drilling operation in the Seiad Creek area of northern California. Two table concentration tests were made on each sample, one dry ...
اقرأ أكثر
Chrome steel from chromium ore processing residue
T1 - Chrome steel from chromium ore processing residue. AU - Kamolpornwijit, Wiwat. AU - Meegoda, Jay N. PY - 2011. Y1 - 2011. N2 - In Hudson County, New Jersey, there are more than two million tons of leftover chromite ore processing residues (COPR). Part of COPR was used as construction fill materials spreading the problem to a larger area.
اقرأ أكثر