Using residual carbon of coal gasification slag as the start of a carbonaceous precursor, hydrodynamic cavitation has been successfully applied to prepare carbon dots (CDs) for the first time. When cavitation bubbles collapse, the comprehensive mechanical effects of shock wave, microjet, and high shear stresses fragment loose …
Цааш унших
Coarse coal gasification slag (CCGS) is formed by melting, cooling, condensing and discharging from the slag outlet at the bottom of the furnace under high temperature and pressure [19].It has a particle size between 3.75 and 9.00 mm and accounts for 60%-80% of the total slag discharge [20].Fine coal gasification slag …
Цааш унших
1. Introduction. Coal gasification slag (CGS) is a solid waste discharged from the coal gasification process [1].Depending on different discharge processes, CGS is mainly classified into coarse slag (furnace bottom slag with grain sizes of 3.75–9.00 mm) and fine slag (less than 50 μm) [2].Approximately 0.15–0.2 tons of CGS are emitted for …
Цааш унших
The coal gasification is the key process of clean usage of coal resource, which inevitably produces a large amount of coal gasification slag (CGS), and causes …
Цааш унших
The stable fluidity of slag at a high temperature is crucial for the long-period operation of an entrained-flow gasifier. The diversity and difference of coal ash make it difficult to meet the requirements for stable slagging in a gasifier. Consequently, coal blending or adding flux has been employed in the industry to improve the fluidity of coal ash slag. As a carbon …
Цааш унших
2.2. One-part geopolymer preparation. The one-part geopolymer samples were prepared using the following procedure: Ⅰ. Mechanically activated specimens: a) The coal gasification slag was ground at different times (0 min, 20 min, 40 min, 60 min, 80 min, and 120 min), and the obtained coal gasification slags were named S-0, S-20, S-40, S …
Цааш унших
Therefore, the utilization of gasification slag is attracting many attentions [7], [8], [9]. The gasification fine slag as one kind of gasification slag is a carbon-containing resource and also rich in silicon and aluminum components [10], [11], [12]. All these components provide a promising source for the preparation of porous materials.
Цааш унших
Coal gasification coarse slag (CGCS) is solid waste generated during coal gasification. The mainly treatment method of CGCS is storage and landfill, which causes severe environmental pollution and waste of land resources. Sodium silicate can be synthesized using CGCS after impurities are removed for the high content of amorphous …
Цааш унших
Fine slag (FS) is an unavoidable by-product of coal gasification. FS, which is a simple heap of solid waste left in the open air, easily causes environmental pollution and has a low resource utilization rate, thereby restricting the development of energy-saving coal gasification technologies. The multiscale analysis of FS performed in this study …
Цааш унших
Slag formation during gasification is related to coal properties, gasifier structure, operating conditions (e.g., temperature, pressure, carbon/oxygen ratio, and fluidized state), and so forth [22]. The main cause of slag formation during gasification or combustion is the large amount of minerals of alkaline-earth and alkali metals that are ...
Цааш унших
Luo et al. [15] used the decarburized coal gasification coarse slag to prepare cement mortar and showed that the flowability of the mortar was improved after the addition of the CGS. Li et al. [16] found a positive interaction between the CGS and the OPC, but the residual carbon influences the hydration process in the reaction. Moreover, …
Цааш унших
To attain high-value utilization of coal gasification fine slag (CGFS), a mechanical-chemical activation treatment for CGFS was presented in this study. Heavy calcium carbonate (CC) was employed as an equivalent filler. The findings demonstrate that the maximum tensile strength and maximum flexural strength of the Poly(vinyl chloride) …
Цааш унших
Coal gasification fine slag is a kind of solid waste with low resource utilization rate. The complex embedding of residual carbon and inorganic minerals (ash materials) is the main reason restricting the …
Цааш унших
To overcome the environmental and economic challenges posed by the increasing amounts of the coal gasification slag, here, a simple and efficient method for enriching the residual carbon from the …
Цааш унших
A considerable volume of coal gasification fine slag (CGFS) has hampered the growth of the coal chemical sector. Carbon/ash separation in CGFS is a prerequisite for efficient treatment and resource utilization. This work focuses on the residual carbon classified separation of CGFS. The composition and structural characteristics of CGFS …
Цааш унших
The coal gasification is the key process of clean usage of coal resource, which inevitably produces a large amount of coal gasification slag (CGS), and causes serious environmental pollution and ecological damage. The high ash content of coal gasification fine slag (CGFS) prevents the efficient utilization of residual carbon in …
Цааш унших
Coal gasification slag is an inevitable by-product of the coal gasification process. This paper explored the feasibility of using activators (calcium hydroxide, sodium hydroxide, calcium sulfate, sodium sulfate) to promote the pozzolanic activity of milled coal gasification coarse slags (MCS), and analyzed the effect of alkali and sulfate activators …
Цааш унших
Coal gasification fine slag (FS) is a typical solid waste generated in coal gasification. Its current disposal methods of stockpiling and landfilling have caused serious soil and ecological hazards. Separation recovery and the high-value utilization of residual carbon (RC) in FS are the keys to realizing the win-win situation of the coal chemical …
Цааш унших
The Fe 2 O 3 /Al 2 O 3 OC showed the highest gasification efficiency among three tested OCs (Fe 2 O 3 /Al 2 O 3, CuO/CuAl 2 O 4, and copper ore) during biomass (pine) CLG [31], [32]. Natural iron ore or industrial ferrous wastes (e.g., red mud, copper slag) are also viewed as good OC candidates because of their lower cost and …
Цааш унших
Phosphate additions to high Cr 2 O 3 refractory have been found to alter slag/refractory interactions and dramatically reduce refractory wear by the following mechanisms: a) …
Цааш унших
1. Introduction. Coal gasification technology is an important development direction of the modern coal chemical industry, and is also one of the core technologies for the clean and efficient utilization of coal [1].The coal gasification process converts coal into syngas (H 2, CO, and CH 4, etc.) through a chemical reaction, which is the industrial …
Цааш унших
Due to lack of sufficient gas or oil reserves, coal plays an important role in China's energy consumption. Efficient utilization of coal is a guarantee for a rapid and stable development of economy [1, 2].Coal gasification has been deemed as the most versatile and clean way to convert coal into electricity, hydrogen, and valuable chemical products [3].
Цааш унших
The coal gasification slag is divided into coal gasification coarse slag and CGFS (see Fig. 1) [6]. The CGFS in the two has a large loss of ignition, high water content, and difficult resource utilization. Moreover, the carbon content is generally over 30 % [7]. At present, there is a deficiency of highly effective methods to address CGFS ...
Цааш унших
In this study, a novel binder was developed by incorporating multiple solid wastes, namely red mud (RM), carbide slag (CS), phosphogypsum (PG), and coal gasification slag (CGS). RM, CS, and PG were used as activators to synergistically activate two kinds of ultra-fine CGS precursors with median particle sizes of 5.2 μm and …
Цааш унших
As the leading industry of coal chemical industry, Coal gasification plays an important role in efficient and clean utilization of coal. It is a process in which solid fuels such as coal, coke, or semi-coke react with gasifying agents under high temperature and pressure to produce gaseous products and a certain amount of slag (Aprianti et al., …
Цааш унших
Coarse coal gasification slag (CCGS) is formed by melting, cooling, condensing and discharging from the slag outlet at the bottom of the furnace under high …
Цааш унших
Gasification in entrained flow reactors is now one of the most dynamically developed technologies of thermal conversion of coal. The basic, solid by-product of this process is slag, and in some cases also fly ash. In Poland, so far there have been no examples of industrial application of coal gasification. However, the high popularity of such systems …
Цааш унших
5.1. Gasification Introduction. Gasification is a technological process that can convert any carbonaceous (carbon-based) raw material such as coal into fuel gas, also known as synthesis gas (syngas for short). Gasification occurs in a gasifier, generally a high temperature/pressure vessel where oxygen (or air) and steam are directly contacted ...
Цааш унших
The structure characteristics and gasification activity of residual carbon from entrained-flow coal gasification slag were mainly investigated using a pore structure analyzer, a scanning electron microscopy, a Raman spectroscopy and a thermo-gravimetric analyzer. Simultaneously, a kind of residual carbon from coal chars was used for a …
Цааш унших
Coal gasification fine slag (CGFS), which is the by-product of entrained-flow coal gasification, has superior properties, such as a large surface area, a broad pore size distribution, and a high content of carbon. This material has the potential to amend poor soils. This study was carried out to investigate the use of CGFS as a soil amendment for …
Цааш унших
Gasification slag exhibits diverse physical properties, such as particle size distribution, density, and porosity. The slag's particle size distribution is influenced by the …
Цааш унших
SEM, particle size analysis, and contaminant content of coarse coal gasification slag (CCGS) produced by Shenhua Xinjiang Chemical Co., Ltd. were measured, respectively, and the …
Цааш унших
Coal gasification slag is formed by physical and chemical transformation of inorganic minerals in coal, which can be divided into coarse slag and fine slag. Coarse slag is produced in the slag discharge mouth of gasifier, accounting for 60–80 %. Its main components are silica, alumina, calcium oxide and iron oxide, etc., with high added value ...
Цааш унших
Copper slag waste heat can provide energy and metallic oxide in copper slag has catalytic effect on carbonaceous solid waste gasification reaction. The gasification energy absorption characteristics and kinetics of typical solid waste, sludge, enteromorpha and lignite with air as oxidation agent has been studied using copper slag …
Цааш унших
Considering the high costs associated with bio-based adsorbents, chemically modified adsorbents, metal organics, and N- or S-containing organic polymers, this study proposed the recovery of gold from printed circuit boards (PCBs) using solid waste coal gasification slag (CGS) as adsorbents. This study found that CGS can quickly adsorb …
Цааш унших
The molten slag was granulated using a rotary cup atomizer and the sensible heat of the slag was recovered by methane-steam reforming reaction. A method for hydrogen-rich syngas production from biomass gasification using slag in continuous moving-bed reactor was used by Luo [12, 13]. The results showed that in the initial stage …
Цааш унших
4.2. Major Gasification Solid Byproducts. As discussed in the Background, solid waste from conventional pulverized coal-fired power plants is a significant environmental issue due to the large quantities produced, chiefly of coal fly ash, and the potential for leaching of toxic substances (e.g. heavy metals such as lead and arsenic) into the ...
Цааш унших
