The resultant products of this process,, (NH 4) 2 SO 4, can be recycled as fertilizers while reducing the discharge of solid or liquid waste. During the desulfurization process, many elements produced from the burned coal, such as metal ions, ash, fluoride, and chloride, are absorbed and accumulated in the desulfurization slurry.
Most of the effective coal desulfurization techniques are based on chemical methods. Main desulfurization methods are chemical desulfurization, leaching, extraction, flotation, oxydesulfurization and biodesulfurization. The alkaline desulfurization is more effective in removing the pyritic sulfur from the coal, which is the less abundant form ...
In addition, the sulfur content of the raw coal reduces from % to %, total desulfurization rate of %, whose organic sulfur desulfurization is % after coal in shake flask experiments. And the desulfurization rate approaches the maximum value on the tenth day (from Figure 2B). It was demonstrated that strain SX12 could ...
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 depending on the process.
The flue gas desulfurization process in coalfired power plants is energy and resourceintensive but the ecoefficiency of this process has scarcely been considered. Given the fluctuating unit load and complex desulfurization mechanism, optimizing the desulfurization system based on the traditional mechanistic model poses a great challenge. In this regard, the present study optimized the eco ...
The complicated mass transfer during coke making process leads to the uneven spatial distribution of sulfur forms in coke, which is of great importance for the sulfur transformation and desulfurization efficiency. ... Char yield and desulfurization rate of YJH coal during pyrolysis. Fig. 5 presents the release rate of H 2 S, SO 2, ...
Flue gas desulfurization (FGD) processes have been widely used since the early 1970's for control of sulfur dioxide emissions from coalfired power plants. First generation FGD systems employ ''wet processes'' whereby the flue gas is contacted with a solution or slurry of an alkali reagent. Most of these installations use either lime or limestone.
Desulfurization systems in coalfired power stations often suffer the problem of high operating costs caused by a ruleofthumb control strategy, which implies great potential for optimization of the operation. ... In this paper, an operation strategy optimization method for the desulfurization process is proposed based on a data mining ...
This study investigated the characteristics of mercury emitted from a largescale coalfired power plant in Taiwan via intensive sampling campaigns. The air pollution control devices equipped in this coalfired power plant include selective catalytic reduction, fabric filter and seawater flue gas desulfurization. During three sampling campaigns, mercury concentrations emitted from this large ...
Flue gas desulfurization (FGD) removes the SO2 from the flue gas of coalfired plants. This postcombustion method is the most widely used technology for controlling SO2 emissions.
Coal desulfurization Full Record Related Research Abstract The Meyers process of removing pyritic sulfur from coal chemically before it is burned is presented.
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 ...
In coal combustion, to generate electric power and process heat, the sulfur is emitted as SO2, which is seen as one of the main causes of acid rain. This effect has led to an interest in the three main methods of removing coal sulfur: coal cleaning, inbed desulfurization, and flue gas desulfurization. Coal cleaning includes physical, chemical,
Pyrolysis desulfurization is suitable for coal. By changing the coking conditions to promote the effusion of sulfide in the form of gas. ... The high temperature, pressure and strong acid or alkali in traditional desulfurization process increase the hazards and bring secondary pollution. Essentially, desulfurization is a combination of ...
XANES was used to analyze the change of sulfur forms in the desulfurization process of high organic sulfur coal under microwave heating and conventional heating conditions. The effects of microwave fields on the molecular properties, bond strength and reaction kinetic of organic sulfurcontaining groups were studied by quantum chemical calculation.
article{osti_, title = {Coal desulfurization by a microwave process}, author = {Zavitsanos, P D and Golden, J A and Bleiler, K W and Jacobs, I S}, abstractNote = {A laboratory size flow reactor was developed and tested on coal samples up to 100 g/batch. A modified version of the applicator will increase sample size to 1000 g; when run continuously it can handle 500 g to 1000 g/minute.
In order to achieve better desulfurization effect, the researchers employ methods of adding chemical additives such as acid, alkali, oxidant, reductant, or changing the reaction atmosphere, or combining with other methods such as magnetic separation, ultrasonic and microorganism.
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. Hence, the comprehensive moisture ...
Sulfur dioxide is the most important precursor of acid rain and one of the major contaminants generated from coalfired power plants. Currently, the limestonegypsum wet fluegas desulfurization (WFGD) system is the most widely used method for removal of SO 2 from powerplant exhaust fumes. However, the gypsum byproduct of limestonegypsum WFGD ...
Coal desulfurization Acid leaching Alkaline leaching Oxidation Microwave Ultrasonic 1. Introduction The main uses of coal are to produce coke for iron smelting, or to generate power for social development, or even to provide raw materials for industrial applications.
The flue gas desulfurization solids in the dry process (DFGDS) are the newly formed CaSO 4 and the unreacted excess of CaO. They are carried along with the coal FA out of the boiler, forming the end product (FA + DFGDS), which is highly alkaline due to the excess of CaO with respect to the initial SO 2 (Ca:S = ). Due to a low ...
Since the "Eleventh FiveYear Plan" period, the construction of flue gas desulfurization and denitrification facilities for coalfired power plants have been accelerated to control the emissions of sulfur dioxide (SO 2) and nitrogen oxides (NO X) and thus to address the issue of acid rain in to the goal of the "Thirteenth FiveYear Plan for Energy Saving and Emission ...
The Energy Information Administration estimates (as of October 2022) that in 2021, CO 2 emissions from burning coal for energy accounted for about 20% of total energyrelated CO 2 emissions and for nearly 60% of total CO 2 emissions from the electric power sector. In the past, fly ash was released into the air through the smokestack ...
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 ...
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.
A novel method for the chemical desulfurization of coal in relatively moderate conditions and short times is presented. Using concentrated hydroiodic acid as a desulfurizing agent and microwaves as the energy source, sulfate and pyritic sulfur are completely removed in 10 min. Moreover, for the lowrank coals studied, variable amounts of organic sulfur, up to 70% in 20 min, can be removed, for ...
![Desulfurization of coal using four ionic liquids with [HSO4]−](/ixy5qbt/127.jpg)
The objective of this study is to develop the extractiveoxidative desulfurization process for cleaning fuel production from coal with ionic liquids, which can be carried out under mild condition. ... Exploration on the action mechanism of microwave with peroxyacetic acid in the process of coal desulfurization. Fuel, Volume 214, 2018, pp. 554560.
At present, the desulfurization technology is divided into pretreatment, inuse treatment, and posttreatment. Inuse treatment, in the case of coal, is generally defined as the spraying of desulfurizer into the coalburning boiler, which is capable of converting SO 2 and SO 3 emissions from coal combustion into sulfites or sulfates (Lu et al. 1998; Sun et al. 2018).
Most of the coal, oil and natural gas produced in the world are used as fuels and a small part is used as a chemical feedstock. Undesulfurized coal and oil in the combustion process will produce a large number of sulfur oxides (SOx), serious harm to human health, and environmental damage. The unpurified natural gas containing hydrogen sulfide (H2S) is difficult for industrial application. 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 desulfurization process took place at a pH of 35, the coalparticle size was 7545 μm, the pulp density was 5%, the temperature was 35°C, and the incubation time was 8 h. Chemical studies also revealed a decrease in the ash content and an increase in the calorific value of coal from 6219 cal/g to 6406 and 6315 cal/g, which indicated ...
Coal desulfurization The development and utilization of traditional coal plays a vital role in promoting social and economic development, but it has brought irreversible pollution to the ecological environment ( Zeng et al., 2021 ).
The combined effect of desulfurization and ash removal in the process of coal desulfurization by microwave with peroxyacetic acid was determined by evaluating variations in minerals and sulfur forms using Xray diffraction and Xray photoelectron spectroscopy. Dielectric properties of minerals or organic sulfur functional groups in coal were studied utilizing a vector network analyzer in the ...
The desulfurization process of circulating fluidized bed desulfurization technology involves the injection of flue gas from the bottom of the fluidized bed through a Venturi tube. ... Microwave heating motivated performance promotion and kinetic study of iron oxide sorbent for coal gas desulfurization. Fuel, 267 (2020), Article 117215, ...
Abstract. Most coal requires some preparation before use. Preparation may range from simply crushing to provide a size consist suitable for certain types of boilers to extensive size reduction and cleaning to remove sulfur and ashforming mineral matter. At present, coal cleaning is accomplished through physical separation of particles low in ...
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