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How is the vacuum pressure swing adsorption (VPSA) oxygen generation technology applied in the smelting of low-grade gold ores?
China's gold resources are rich in reserves and widely distributed. In recent years, with the development and progress of smelting technology, gold smelters represented by Zijin Mining Group Co., Ltd. (one of the world's leading mining groups) have started to focus on low-grade gold ores. Adopting low-cost enriched oxygen, Zijin Mining has even overcome the pressurized pre-oxidation technology of refractory gold ore processing, and further reduced the smelting cost of low-grade gold ores.
It is reported that the pressurized pre-oxidation technology has the advantages of faster reaction rate, stronger adaptability, higher recovery rate, and being more environmentally friendly compared with the oxidation roasting and bacterial oxidation methods that have been industrially applied in China. More importantly, the industrial application of the technology will effectively avoid hazardous gas emissions and achieve zero discharge of production wastewater and stable storage of waste residues, which is a breakthrough in the transformation from the rough development of the traditional mining industry to the new green development.
Generally, pressurized pre-oxidation technology requires rich oxygen with a purity of about 90% and capacity of 5000~10000Nm³/h, for which vacuum pressure swing adsorption (VPSA) oxygen generation is more suitable. Especially with many advantages such as lower investment and power consumption, flexible turndown ratio regulation and easy start-up and shutdown, the technology is conducive to further reducing the gold smelting cost to create higher benefits for enterprises. The application of this technology has great value in promoting the pressurized oxidation process of low-grade refractory gold and polymetallic metals. Also, it's of great significance to the environmental protection in the mining industry, the overall technical improvement of gold and other metal industries, and the technological progress of the related equipment manufacturing industries.
On the other hand, the VPSA & PSA oxygen units can provide enriched oxygen for gold ore roasting, smelting and other processes. Oxygen-enriched combustion can effectively improve the smelting rate and combustion intensity, which is beneficial to improving the gold recovery rate & throughput, and reducing flue gas emissions and environmental pollution at the same time.
As a global well-known supplier of VPSA oxygen generation equipment in the field of non-ferrous Metallurgy, PKU Pioneer has provided nearly 60 sets of VPSA oxygen systems for more than 40 non-ferrous metal smelters, including world-leading enterprises that have continuously purchased 5 sets of oxygen units in the industry, helping customers to significantly cut smelting costs and improve overall economic efficiency. PKU Pioneer has nearly 23 years of technological research and engineering implementation experience in VPSA & PSA oxygen production and has provided a total of 300+ sets of high-quality oxygen equipment with a total cumulative oxygen capacity of 1,600,000Nm3/h for 15+ countries around the world. As the largest supplier of VPSA & PSA oxygen generators in China, PKU Pioneer will continue to uphold the service concept of "Creating Maximum Value to Customers" and provide powerful assistance to the customers.
What else can I help you with?
Why physical adsorption is reversible process?
adsorption is processs of accumulation of liquid/gases on solid surface. reversible adsorption is seen in physical adsorption where increase in pressure increases the adsorption and decrease in pressure decrease adsorption of molecules to surface that is desorption takes place
What has the author Douglas M Ruthven written?
Douglas M. Ruthven has written: 'Pressure swing adsorption' -- subject(s): Adsorption
What is Freundlich adsorption isotherm and Langmuir isotherm?
At a given temperature, the extent of adsorption will increase with the increase of pressure of the gas. The extent of adsorption is measured as x/m, where mi= is the mass of adsorbent and x that of adsorbate. At low pressure, x/m varies linearly with p. As per Freundlich adsorption equation Taking log both sides of the equation, we get, At low pressure, x/m=kP At high pressure, x/m=kPo This is called Freundlich adsorption isotherm at a constant temperature. Freundlich isotherm fails at high pressure and is only for physical adsorption. Langmuir isotherm is represented as x/m=ap/(1+bp) (a and b are constants) At very high pressure,(bp>>1) x/m=a/b At very low pressure,(bp<<1) x/m=ap
Why does pressure not have effect on adsorption when the case is solutions on solids?
In the case of adsorption from solutions onto solids, pressure has minimal effect because the adsorption process is primarily driven by concentration rather than pressure. The solute concentration in the solution determines the availability of molecules to interact with the solid surface. As long as the concentration remains constant, increasing pressure does not significantly influence the adsorption equilibrium. Additionally, the solid's surface interactions and the nature of the solute-solvent interactions are more critical factors in this scenario.
Why freundlich adsorption isotherm is not applicable at high pressure?
Freundlich adsorption isotherm assumes a homogeneous surface with a finite number of adsorption sites, making it unsuitable for high pressures where interactions between adsorbate molecules become significant. At high pressures, multilayer adsorption occurs, violating the assumptions of the Freundlich isotherm which fails to account for these complex interactions. As a result, Freundlich isotherm is not applicable in conditions where multilayer adsorption dominates.
What are the disadvantages of Frenlich adsorption isotherm?
Frenlich adsorption isotherm has no theoretical basis. There are high chances of it failing when the concentration of the adsorbate is high. The equation is, usually, invalid at high pressure.
Does pressure effect on adsorption of oxygen?
Yes. Pressue effects both adsorption and absorption of oxygen. I assume you really did mean adsorption (and not absorption) but just in case, this answer addresses both - since the answer is similar. As pressure increases, the fugacity of oxygen in the liquid or vapor phase will also increase. In order to stay in equilibrium, you would expect the concentration of oxygen on a surface (adsorption) to increase as well. There is one caveat in that if the oxygen is in a mixture, the fugacity of the other components of the mixture will also be increasing and may be in competition with the oxygen for adsorption to the surface. Once the surface is saturated, raising the pressure may not have any effect on the adsorption. Likewise, dropping the pressure will decrease the fugacity of oxygen in the fluid phase and promote desorption from a surface (the reverse of adsorption). Similarly, increasing or decreasing pressure will increase and decrease the fugacity of oxygen in the vapor phase and require more or less oxygen to be absorbed into a liquid (or in some cases solids - although most solids don't dissolve gasses very well). Increaing pressure can also change the distribution of oxygen between two immiscible liquids as the fugacity of the oxygen in each depends on both pressure and the effect of pressure on the fugacity of the solvent liquids.
How do they capture oxygen into the tank?
Oxygen is captured into tanks through processes like cryogenic distillation, pressure swing adsorption, or membrane technology. These methods involve separating oxygen from the air and compressing it into the tank for storage and later use.
What is swing adsorption?
Pressure Swing Adsorption refers to the process of purification of Hydrogen gas which is manufactured in a plant like rfinery. Hydrogen which is formed as a by-product in process like Reforming is also used as a raw material within the refinery process like Hydrotreating and Isomerization. So it has to be made impurities free for use. So Hydrogen is purified by the process known as pressure swing adsorption in which impurities are adsorbed on the surface and Hydrogen becomes clean.
What has the author Stephen Nicholas Barker written?
Stephen Nicholas Barker has written: 'A survey of pressure swing adsorption cycles'
Why in adsorption GIBBS free energy decreases?
In adsorption, Gibbs free energy decreases because the adsorbate molecules are attracted to the surface of the adsorbent, reducing the overall energy of the system. This leads to a more stable configuration with a lower free energy. The decrease in Gibbs free energy indicates that the adsorption process is spontaneous at a given temperature and pressure.
What is the difference between the Freundlich and Langmuir adsorption isotherms?
ADSORPTION ISOTHERMA mathematical equation, which describes the relationship between pressure (p) of the gaseous adsorbateand the extent of adsorption at any fixed temperature, is called adsorption isotherm.The extent of adsorption is expressed as mass of the adsorbateadsorbed on one unit mass of the adsorbent.Thus, if x g of an adsorbateis adsorbed on m g of the adsorbent, thenExtent of adsorption =z/mVarious adsorption isotherms are commonly employed in describing the adsorption data.(1) Freundlichadsorption isotherm(i) Freundlichadsorption isotherm is obeyed by the adsorptions where the adsorbateforms a monomolecular layer on the surface of the adsorbent.x/m =kp1/n (Freundlichadsorption isotherm) orlog x/m =log k + 1/n log Pwhere x is the weight of the gas adsorbed by m gm of the adsorbent at a pressure p, thus x/m represents the amount of gas adsorbed by the adsorbents per gm (unit mass), k and n are constant at a particular temperature and for a particular adsorbent and adsorbate(gas), n is always greater than one, indicating that the amount of the gas adsorbed does not increase as rapidly as the pressure.(ii) At low pressure, the extent of adsorption varies linearly with pressure. x/m ∝ p'(iii) At high pressure, it becomes independent of pressure. x/m ∝ p0(iv) At moderate pressure x/m depends upon pressure raised to powers x/m ∝ p1/n(2) The Langmuir - adsorption isotherms(i) One of the drawbacks of Freundlichadsorption isotherm is that it fails at high pressure of the gas. Irving Langmuir in 1916 derived a simple adsorption isotherm, on theoretical considerations based on kinetic theory of gases. This is named as Langmuir adsorption isotherm.(a) Adsorption takes place on the surface of the solid only till the whole of the surface is completely covered with a unimolecularlayer of the adsorbed gas.(b) Adsorption consists of two opposing processes, namely Condensation of the gas molecules on the solid surface and Evaporation (desorption)ofthe gas molecules from the surface back into the gaseous phase.(c) The rate of condensation depends upon the uncovered (bare) surface of the adsorbent available for condensation. Naturally, at start when whole of the surface is uncovered the rate of condensation is very high and as the surface is covered more and more, the rate of condensation progressively decreases. On the contrary, the rate of evaporation depends upon the covered surface and hence increases as more and more of the surface is covered ultimately an equilibrium will be set up at a stage when the rate of condensation becomes equal to the rate of evaporation (adsorption equilibrium).(d) The rate of condensation also depends upon the pressure of the gas since according the kinetic theory of gases, the number of molecules striking per unit area is proportional to the pressure.Mathematically, x/m =ap/1+bp, where a and b are constants and their value depends upon the nature of gas (adsorbate),nature of the solid adsorbent and the temperature. Their values can be determined from the experimental data.Limitation of Langmuir theory(a) Langmuir's theory of unimolecularadsorption is valid only at low pressures and high temperatures.(b) When the pressure is increased or temperature is lowered, additional layers are formed. This has led to the modern concept of multilayer adsorption.
