Fluidized Bed Technology for Gold Ore and Gold Concentrate
This paper describes the different options of the fluidized bed technology for gold roasting reflecting on main process design criteria.
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This paper describes the different options of the fluidized bed technology for gold roasting reflecting on main process design criteria.
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Commercially, four important steps have been witnessed in the development of roaster equipment: • Rotary kiln and multiple hearths (e.g. Edwards)Fluidized bed (e.g. DORR-Oliver)Circulating fluidized bed (CFB) (e.g. Inco and Lurgi)Oxygenated fluidized bed (e.g. Independence and Goldstrike)Table 1 summarizes the advantages and …
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Learn about the basic configuration, operation and characteristics of circulating fluidized beds (CFB), a type of gas-solids contacting system. Compare CFB with low-velocity …
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not efficient at recovering certain particles such as fine free gold and some free gold laminar particles which have natural buoyancy characteristics. for this reason, Mineros …
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Since Fluidized bed combustors involve a bed of inert material (sand, ash, …), primary and secondary combustion air, a waste feed of varying composition and consistence according to the source, and the possible evaporation of water in the case of a wet feed, the design needs to account for these various inputs and is performed …
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Circulating fluidized-bed (CFB) technology has been successfully applied to the roasting of refractory gold ores and concentrates on both pilot plants (200, 350 and …
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Fluidized-bed gasifiers suspend feedstock particles in an oxygen-rich gas so the resulting bed within the gasifier acts as a fluid. These gasifiers employ back-mixing, and efficiently mix feed coal particles with coal particles already undergoing gasification. To sustain fluidization, or suspension of coal particles within the gasifier, coal of ...
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Study on mechanism of carbonaceous gold ore during oxidation roasting by kinetics: phase transformation and structure evolution. The pretreatment and effective utilization of …
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DOI: 10.21000/JASMR94040218 Corpus ID: 133118572; ACID MINE DRAINAGE ABATEMENT USING FLUIDIZED BED COMBUSTION ASH GROUT AFTER GEOPHYSICAL SITE CHARACTERIZATION @article{Schueck1994ACIDMD, title={ACID MINE DRAINAGE ABATEMENT USING FLUIDIZED BED COMBUSTION ASH GROUT …
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Because of the high relative SG of gold, and the fact that some forms of gold such as free gold do not break apart during conventional grinding, coarse gold can accumulate in the circulating load, and eventually be lost.Eriez has developed a flotation cell that uses fluidized water to enhance flotation of coarse particles. More than 40 units ...
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Learn how fluidization occurs when a gas imposes a drag force on particles and how to design a fluidized bed reactor. Find out the benefits and challenges of …
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The fluidized bed technology is positioned between a fixed bed like a grate furnace where the fuel particles are rather fixed on the grate and an entrained flow where the fuel particles are in a state of pneumatic transport (refer also to Lackner et al. 2010).In fluidized bed technology, the fuel particles are mixed with bed material usually made …
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The acid mine drainage (AMD) released from coal and gold mining activities often has a low pH value due to containing high concentrations of heavy metals (e.g. Al, Fe, Cu, etc.). ... Biological oxidation of ferrous iron in high acid mine drainage by fluidized bed reactor. Water Sci Technol, 23 (7–9) (1991), pp. 1447-1456. Crossref View in ...
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This work aims to design and demonstrate a novel fluidized bed catalytic reactor/receiver system to drive endothermic steam and dry reforming processes for syn-gas ... Colorado School of Mines 1500 Illinois St., Golden, CO 80401 303-273-3000 / 800-446-9488. Admissions & Financial Aid Financial Aid Graduate Admissions Undergraduate …
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Fluidized bed electrodes (FBEs), which were discovered in the late 1960s, are 3D (three-dimensional) particle electrodes. The FBEs have been attracting extensive attention because of their unique properties and advantages, such as higher space-time yield, high active electrode area, and higher mass transfer rate than conventional …
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We previously studied the feasibility of using GF fly ash in cemented backfill mining (Li et al., 2020); the slag-fly ash-based cemented material system disintegrates the network structure of the glass body in the BFS under the FGD gypsum and GF fly ash excitation, such as [SiO 4] 4− and [AlO 4] 5−, and the microscopic physical …
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Fluidized-bed denitrification for mine waters. Part I: low pH and temperature operation S. Papirio • A. Ylinen • G. Zou • M. Peltola • G. Esposito • J. A. Puhakka Received: 17 July 2013/Accepted: 24 October 2013/Published online: 29 October 2013 Springer Science+Business Media Dordrecht 2013 Abstract Mining often leads to nitrate and ...
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The results show that the static bed height should be controlled near 300 mm (e.g., 300–350 mm). The bubble size, amount, and frequency of the fine particle bed are smaller than those of the bed containing 0.3–0.15 mm large Geldart B particles, thus leading to a higher bed activity.
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Figure 3. The bed transitions from a bubbling fluidized bed to a turbulent fluidized bed in which the gas voids are no longer regularly shaped bubbles, but rather have elongated shapes. The top of the bed becomes less well defined due to the increase in entrained particles. At even higher gas
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Circulating fluidized bed combustion systems have proven to be among the best coal power plant technology currently available. ... For comparison, lignite from other mines has a general ...
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ACID MINE DRAINAGE ABATEMENT USING FLUIDIZED BED COMBUSTION ASH GROUT AFTER GEOPHYSICAL SITE CHARACTERIZATION1 Joseph Schueck,2 Terry Ackman,3 and Barry Scheetz4 Abstract: Pyritic coal refuse and pit cleanings buried in a 15-ha (37-acre) surface mine produce severe acid mine drainage (AMD). The pyritic material
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Acid mine drainage is an important environmental problem related to the release of acidic, sulfate-, and metal-containing wastewater into the environment. Sulfate-reducing bacteria can be used for treating mining wastewaters and recovering metals in several bioreactor configurations. The fluidized-bed configuration is an efficient way for …
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DOI: 10.1016/B978-0-444-63658-4.00024-4 Corpus ID: 102315110; Chapter 24 – Roasting of Gold Ore in the Circulating Fluidized-Bed Technology @inproceedings{Hammerschmidt2016Chapter2, title={Chapter 24 – Roasting of Gold Ore in the Circulating Fluidized-Bed Technology}, author={J{"o}rg Hammerschmidt and …
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Fig. 3 displays the pressure fluctuations time series at four fluidization regimes in the gas-solid fluidized bed. As for the single-bubble regime, in Fig. 3 (a), the periodicity of the pressure signals is vividly observed, which can be measured by simply counting the number of peaks in the time series. As counted, there are seven peaks or …
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has over 30 years of fluidized bed history and has over 200 systems installed under the Pyrotherm, Svedala, and Allis Chalmers brands. fluid bed technology has a proven track record of excellence and has a lower CAPEX and OPEX versus other cooling, drying, heating, and calcining technologies. High throughput rates – up to 600 tph
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Three fixed bed reactors & processed 2,000 barrels/day Other adoptees: Sun, Gulf, Sinclair, Standard Oil of Ohio, & The Texas Company Sun & Houdry started developing moving bed process in 1936 1st commercial 20,000-barrel/day unit commissioned at Magnolia's Beaumont Refinery in 1943 Fluidized bed catalytic cracking
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The results show that bed temperature distribution beco... In this study, the experiments were carried out in a circulating fluidized bed with different coal bed …
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Gold roasting is typically a metallurgical fluidized bed process. Process and equipment design have been influenced by other fluidized bed metallurgical processes (e.g., alumina calcination ... Practical Considerations in the Hydro Re-Mining of Gold Tailings. Gold Ore Processing, 2016, pp. 729-738. J. Wates, A. Götz. Developments in …
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However, in a Fluidized Bed (see Section 2.4), due to intense mixing causing high heat and mass transfer rates between the reactants, the locations of the reaction zones will depend on the geometry of the reactor and the distribution of the feed points. Typically the engineering will aim to realize the char combustion zone close to the oxidant ...
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Any vessel in which solids are transported upward by a gas stream and then recycled to the bottom may be classified as a Circulating Fluidized Bed (CFB). We describe possible CFB operating regimes in the context of this broad classification and highlight commercial processes that employ CFB technology and potential applications.
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Static Bed Height The transition velocity was almost independent of the static bed height, which varied from 0.4 to 1.0 m (Grace and Sun 1990). Similar results were reported by Cai (1989) and Satija and Fan (1985) with (Hmf/Dt) > 2. On the other hand, for a shallow fluidized bed of (Hmf/Dt) < 2 with Group B and D particles, Canada et
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Given that the different regions of the fluidized bed exhibit varying dynamics, which together contribute to overall bed dynamics, the bed transients in the upper, central, and lower regions of the fluidized bed are monitored using several sensitive pressure transducers located along the height of the bed. The effect of the flow pulsation on ...
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Learn about the concept, history and applications of fluidization, a process of making solid particles fluid-like. Explore the different modes, regimes, simulations and …
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The paper presents the results from studies on co-combustion of dry, "high" calorific value wastes with/without supplementary fuels. Two fluidisation techniques were employed, circulating and bubbling, in facilities of three sizes; a bench scale circulating fluidized bed combustor (CFBC) designed to burn coal and two were bubbling fluidised bed reactors …
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In bubbling fluidized bed combustors (BFBC), an initially stationary bed of solid particles, located in the bottom part of the combustor, is brought into a fluidized state by primary air, supplied through a distributor: the bed particles are kept in suspension at fluidization velocities between 0.5 and 3.0 m/s. For BFBC applications, the size ...
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The fluidized-bed reactor is the centerpiece of industrial fluidization processes. This book focuses on the design and operation of fluidized beds in many different industrial processes, emphasizing the rationale for choosing fluidized beds for each particular process. The book starts with a brief history of fluidization from its inception in ...
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