In this study, coal fly ash was functionalized, using a simple onestep process (loading with Al3+ and sulfonation), to yield a solid acid catalyst (S/AlCFA) with strong acid sites. The catalyst was then used to produce furfural from xylose in a biphasic system (H2O(NaCl)/tetrahydrofuran). The furfural yield reached 82% at 180 °C60 min with catalyst/xylose ratio of : (w/w).
The occurrence of sulfur in coal direct liquefaction residue affects its further high quality and high value utilization. Electrochemical desulfurization is characterized by mild reaction conditions, simple operation, easy separation of sulfur conversion products and little influence on the properties of the liquefied residue. An anodic electrolytic oxidation desulphurization experiment was ...
This paper briefly introduces various methods of coal desulfurization (physical desulphurization, chemical desulfurization, biological desulfurization, etc.) and analyzes some problems existing in each method. The principle and research process of friction electrostatic separation technology and high gradient magnetic separation technology in precombustion desulfurization technology are ...
The most commonly required desulfurization process is in natural gas. Additional desulfurizing is required for flue gas, coal, and oil. Natural gas desulfurization is typically accomplished by adsorption. A bed of activated carbon is used as the filter for natural gas pipelines. As the natural gas runs through the pipeline, it runs through the ...
Physical desulfurization methods can only remove inorganic sulfur and are economical and practical in nature. 14,15 Highgradient magnetic separation technology is an effective method for physical desulfurization, which can be used to deal with fine particles of paramagnetic minerals and is applied to the desulfurization of fine coal (mainly ...
In 1978, Kirkbride proposed a desulfurization process: the raw coal will be properly pulverized, dried to remove free water, mixed with hydrogen and then treated by microwave radiation. H 2 reacts with S, N and O in coal producing H 2 S, NH 3 and water vapor thus achieving the purpose of desulfurization. The coal shall be as dry as possible ...
That shows desulfurization reaction in the furnace is complete. At the same time, the composition of fly ash and circulating ash are similar to each other. Before the renovation, desulfurizer is only active calcium in the raw coal during desulfurization process.
Desulphurization of High Sulfur Coal by Mild Pyrolysis Combination with Magnetic Separation. Quanrun Liu H. Xia Guangxu Huang Chuanxiang Zhang M. Ma C. Wan. Materials Science, Chemistry. 2012. In this work, a new desulfurization process of high sulfur coal was designed and examined. The novel process involved pyrolysis of high sulfur coal at ...
The major coal desulphurization technologies prior to combustion are physical coal cleaning, chemical and biological methods. Each has some technical and economical limitations. Physical coal cleaning can only remove limited amount of inorganic sulphur due to insufficient liberation. Fine grinding can liberate fine pyrites, where novel coal ...
1000MW coalfired power plants using limestone gypsum wet desulphurization process are selected as the sample to . ... From the change of annual desulfurization cost of coalfired power plants (as .
An alternative technology is the Alstom NID (Novel Integrated Desulfurization) process, as shown in Figure 3. A principal feature of this system is the Jtube reactor, whose outline is evident in ...
Coal, as a fossil fuel, contains carbon, hydrogen, sulphur, oxygen and element of acidic. Therefore, the combustion of coal contributes to the emission of SO 2, CO 2, and NOx into the atmosphere [14]. CO 2, NOx and SO 2, which is combustible, is produced during the coal combustion process.. As discussed earlier, the release of CO 2
Coalfired power plants can improve wet limestone scrubbing with advanced process control. ... The chemical reaction formula for this desulfurization process is: CaCO 3 + SO 2 + 2 H 2 O +½ O 2 ...
Desulfurization Download as a PDF or view online for free. Desulfurization Download as a PDF or view online for free ... Flue gas desulphurization detailed process may021994. ... About 2 g of coal (< 250 μm) in 70 mL of glacial acetic acid and 30 mL of 6% hydrogen peroxide concentration were reacted at room temperature for a specific ...
Flue gas desulphurisation (FGD) describes a process that removes sulphur dioxide (SO2) from a flue gas ( exhaust gas) stream. Sulphur dioxide is released to the atmosphere when fossil fuels are burnt and it is a leading contributor to acid rain. The FGD process has become critical to many industrial plants due to increasingly stringent ...
environment, the desulfurization and denitration of flue gas in the combustion process of coal has become an important step. This work summarizes the desulfurization and denitration ... In the wet desulfurization process, the scaling and blockage of equipment are easy to occur in the process site. In view of the above problems, a calciumsodium ...
Solid Wastes. Nicholas P. Cheremisinoff, in Clean Electricity Through Advanced Coal Technologies, 2012 FlueGas Desulfurization Material. Fluegas desulfurization (FGD) material is a product of a process typically used for reducing SO 2 emissions from the exhaust gas system of a coalfired boiler. The physical nature of these materials varies from a wet sludge to a dry, powdered material ...
A flue gas desulfurization (FGD) processing unit, generally known as a scrubber, eliminates sulfur dioxide (SO 2) from the exhaust flue gases in power plants in which coal is burnt. Airborne SO 2 forms sulfuric acid (H 2 SO 4) by oxidizing within airborne water droplets, resulting in "acid rain". Due to the stringent environmental emissions ...
The process involves the treatment of crushed coal with an aqueous leaching solution of ferric sulfate which reacts with the coal pyrites to yield soluable ferrous sulfates and elemental sulfur. The solution is drained off and the leaching solution can be regenerated with the production of calcium sulfate (gypsum) and iron oxides.
Process development of flue gas desulphurization wastewater treatment in coalfired power plants towards zero liquid discharge: Energetic, economic and environmental analyses. Xiaoqu Han Dan Zhang Junjie Yan Zhao Shuran Jiping Liu
Oxidation is the most widely used process for coal desulfurization [17, 2932] due to its ability to . remove the p yritic sulfur [33] and the macromolecular network [34].
The flue gas desulphurization can be done both by wet or dry process. The most widespread process is wet desulphurization of limestone or lime, accounting for about 85% of all desulphurization ...
As a typical industrial byproduct during the flue gas desulfurization process of coalfired, flue gas desulfurization ash (FGDA) with alkali mineral can facilitate the water damage resistance of asphalt mixtures. However, low density and high hydrophilic coefficient of FGDA limit its improvement effect.
The coal hydrogen production process requires hightemperature steam as a reactant. Coalfired boilers are usually used to provide hightemperature steam. The ammoniabased desulphurization process is an effective technology to remove SO2 in the coalfired flue gas. However, the mass transfer coefficient of SO2 in such an engineered process is not readily available in the literature. In this ...
Mechanism of Pyrite Microbial Desulfurization. The oxidation process of coal conversion is possible by microorganisms after getting influenced by the polyfunctional coal structure and this process usually depends on two main factors: size or shape of coal and surface properties of microorganisms (Konishi et al. 1990). The morphology and ...
The process of bacterial coal desulfurization led to increase in calorific value showing advantage over conventional treatment methods. The optimum conditions of treatment time, pH, temperature, and coal pulp density for coal desulfurization by Aspergillus sp. was denoted as 8 days,, 35°C, and 5%, respectively ( Liu et al., 2017a ).
The flue gas desulfurization (FGD) plant removes sulfur dioxides (SO 2) from flue gas produced by boilers, furnaces, and other sources. Mitsubishi Power effectively contributes to the prevention of air pollution through its wet limestonegypsum FGD process and seawater FGD process, and both processes can treat a large range of SO 2 ...
A novel approach is developed for desulphurization of fuels or organics without use of catalyst. In this process, organic and aqueous phases are mixed in a predefined manner under ambient ...
The addition of MPS or ZCS can help the materials stratify strictly according to the density to enhance the sorting function. The clean coal ash and sulfur content are reduced to % and %, while the combustible recovery and desulfurization efficiency are up to % and %, respectively, under the optimal condition.
The adsorption capacity of Sorbacals during the desulphurisation process of flue gases in the temperature range of 110130°C is discussed in detail in . ... J. Krátký, and L. Veverka, "The causation of high consumption of limestone in coal fluidized bed boiler desulfurization," CeramicsSilikáty, vol. 54, no. 1, pp. 8588, 2010.
Flue gas desulfurization (FGD) systems using lime or limestone as the chemical reagent are widely used throughout the world for SO 2 emissions control at coalfired power plants. Ammoniabased ...
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