High-efficiency removal of Cr(VI) in wastewater via coal gasification slag-based porous composite material

A large amount of coal gasification slag is produced every year in China. However, most of the current disposal is into landfills, which causes serious harm to the environment. In this research, coal gasification fine slag residual carbon porous material (GFSA) was prepared using gasification fine slag foam flotation obtained carbon residue (GFSF) as raw material and an adsorbent to carry out an adsorption test on waste liquid containing methylene blue (MB). The effects of activation parameters (GFSF/KOH ratio mass ratio, activation temperature, and activation time) on the cation exchange capacity (CEC) of GFSA were investigated. The total specific surface area and pore volume of GSFA with the highest CEC were 574.02 m2/g and 0.467 cm3/g, respectively. The degree of pore formation had an important effect on CEC. The maximum adsorption capacity of GFSA on MB was 19.18 mg/g in the MB adsorption test. The effects of pH, adsorption time, amount of adsorbent, and initial MB concentration on adsorption efficiency were studied. Langmuir isotherm and quasi second-order kinetic model have a good fitting effect on the adsorption isotherm and kinetic model of MB.

Preparation of hierarchically porous carbon ash composite material from fine slag of coal gasification and ash slag of biomass combustion for CO2 capture

Waste coal gasification fine slag disposal mode via a promising “efficient non-evaporative dewatering & mixed combustion”: A comprehensive theoretical analysis of energy recovery and environmental benefits

Distribution modes of residual carbon and ash in coal gasification fine slag and its feasibility analysis as particle electrodes

Review on the attribute cognition and carbon-ash-water separation of coal gasification fine slag

Structural features and combustion reactivity of residual carbon in fine slag from entrained-flow gasification

Occurrence modes of water in gasification fine slag filter cake and drying behavior analysis——A case study

Cyclic catalytic Fe-N doped composite particle electrodes derived from gasification fine slag for non-selective mineralization of organic wastewater

A novel adsorbent of core-shell construction of chitosan-cellulose magnetic carbon foam: Synthesis, characterization and application to remove copper in wastewater

Experimental study on preparation of oxygen reduction catalyst from coal gasification residual carbon

Efficient dewatering of waste gasification fine slag based on mechanical pressure-vacuum fields: Dewatering characteristics, energy optimization and potential environmental benefits

To explore the effect of coal water slurry (CWS) gasification slag on the soil water physical characteristics of saline-alkali soil in the Yellow River Basin of Inner Mongolia, CWS gasification coarse slag (GCS) and gasification fine slag (GFS) were used as improvement materials and mixed with saline-alkali soil in different proportions. The influence mechanism of GCS and GFS on saline-alkali soil water holding capacity was investigated by measuring particle size composition, water holding capacity, and the change in the soil water characteristic curve after mixing. The results showed that adding gasification slag improved the particle size composition of saline-alkali soil, with sand content increased by -3.79%~217.31% and clay and silt content decreased by 5.77%~56.50% and -0.38%~41.53%, respectively. Soil bulk density decreased significantly ( P < 0.05 ), with a decrease range of 15.17%~45.1%. The soil texture changed from silty loam to sandy loam, and the water retention performance improved, affecting the soil saturated water content, capillary water holding capacity, and field water holding capacity ( P < 0.05 ), with increases ranging from 20.75%~86.15%, 7.84%~27.81%, and -1.89%~34.56%, respectively. After adding GCS and GFS, the VG model fit the soil water characteristic curve of saline-alkali soil well, indicating that the addition of gasification slag enhanced soil water retention significantly. In conclusion, CWS gasification slag effectively improved the water physical properties of saline-alkali soil and significantly enhanced the water retention and water holding capabilities.

The industrial practice of fine coal processing

A new separation flowsheet for resources recovery from waste coal gasification fine slag black water and its benefits analysis

Insights on water temporal-spatial migration laws of coal gasification fine slag filter cake during water removal process and its enlightenment for efficient dewatering