Zeolite derived from coal-based solid wastes(coal gangue and coal fly ash)can overcome the environmental problems caused by coal-based solid wastes and achieve valuable utilization.In this paper,the physicochemical pr...Zeolite derived from coal-based solid wastes(coal gangue and coal fly ash)can overcome the environmental problems caused by coal-based solid wastes and achieve valuable utilization.In this paper,the physicochemical properties of coal gangue and coal fly ash are introduced.The mechanism and application characteristics of the pretreatment processes for zeolite synthesis from coal-based solid wastes are also introduced.The synthesis processes of coal-based solid waste zeolite and their advantages and disadvantages are summarized.Furthermore,the application characteristics of various coal-based solid waste zeolites and their common application fields are illustrated.Finally,we propose an alkaline fusion-assisted supercritical hydrothermal crystallization as an efficient method for synthesizing coal-based solid waste zeolites.In addition,more attention should be given to the recycling of alkaline waste liquid and the application of coal-based solid waste zeolites in the field of volatile organic compound adsorption removal.展开更多
The manufacturing of ordinary Portland cement is an energy-intensive process that results in pollution and CO2 emissions,among other issues.There is a need for an environmentally friendly green concrete substitute.Was...The manufacturing of ordinary Portland cement is an energy-intensive process that results in pollution and CO2 emissions,among other issues.There is a need for an environmentally friendly green concrete substitute.Waste products from a variety of sectors can be recycled and used as a green concrete substitute.This decreases the environmental effects of concrete manufacturing as well as energy consumption.The use of solid waste materials for green building is extremely important now and in the future.Green concrete is also in its infancy in terms of manufacturing and application.Academics must intervene by encouraging business implementation.The aim of this review paper is to raise awareness about the importance of repurposing recycled materials and to highlight new technologies for producing green,sustainable concrete.展开更多
The clayish crushed stone was used for making aerated concrete. Through studying hydro-thermal synthesis reaction, mix ratio, gas-forming and performance analysis, Grade-B05 and Grade-B06 aerated concrete were prepare...The clayish crushed stone was used for making aerated concrete. Through studying hydro-thermal synthesis reaction, mix ratio, gas-forming and performance analysis, Grade-B05 and Grade-B06 aerated concrete were prepared successfully. The proper mix ratio and key processing parameters were achieved. The microstructure of aerated concrete with crush stone was analyzed by means of XRD and SEM. The experimental results indicate that the hydration products are poorly crystalline C- S- H ( B ), tobermorite and hydrogarnet. No componeat of clay was found. Unreacted SiO2 cart be in existence, and the structure system of aerated concrete is homogencous and dense.展开更多
The destruction of concrete building materials in severely cold regions of the north is more severely affected by freeze-thaw cycles,and the relationship between the mechanical properties and pore structure of concret...The destruction of concrete building materials in severely cold regions of the north is more severely affected by freeze-thaw cycles,and the relationship between the mechanical properties and pore structure of concrete with fine aggregate from municipal solid waste(MSW)incineration bottom ash after freeze-thaw cycles is analyzed under the degree of freeze-thaw hazard variation.In this paper,the gray correlation method is used to calculate the correlation between the relative dynamic elastic modulus,compressive strength,and microscopic porosity parameters to speculate on the most important factors affecting their changes.The GM(1,1)model was established based on the compressive strength of the waste incineration ash aggregate concrete,the relative error between the simulated and actual values in the model was less than 5%,and the accuracy of the model was level 1,indicating that the GM(1,1)model can well reflect the change in the compressive strength of the MSW incineration bottom ash aggregate concrete during freeze-thaw cycles.Using the gray correlation method,the correlation between the relative dynamic elastic modulus,compressive strength,air content,specific surface area,pore spacing coefficient,and pore average chord length was calculated,and the pore spacing coefficient and pore average chord length were determined to be highly correlated with each other.This determination can help analyze and infer the deterioration mechanism of concrete subject to freeze-thaw cycles.These results can provide a theoretical basis for guiding the engineering practice of concrete with fine aggregates of household bottom ash in the northern cold region.展开更多
基金This work was financially supported by the National Key R&D Program of China(Nos.2020YFC1806504 and 2019YFC1904903)the Yue Qi Young Scholar Project,China University of Mining&Technology(Beijing)(No.2017QN12).
文摘Zeolite derived from coal-based solid wastes(coal gangue and coal fly ash)can overcome the environmental problems caused by coal-based solid wastes and achieve valuable utilization.In this paper,the physicochemical properties of coal gangue and coal fly ash are introduced.The mechanism and application characteristics of the pretreatment processes for zeolite synthesis from coal-based solid wastes are also introduced.The synthesis processes of coal-based solid waste zeolite and their advantages and disadvantages are summarized.Furthermore,the application characteristics of various coal-based solid waste zeolites and their common application fields are illustrated.Finally,we propose an alkaline fusion-assisted supercritical hydrothermal crystallization as an efficient method for synthesizing coal-based solid waste zeolites.In addition,more attention should be given to the recycling of alkaline waste liquid and the application of coal-based solid waste zeolites in the field of volatile organic compound adsorption removal.
文摘The manufacturing of ordinary Portland cement is an energy-intensive process that results in pollution and CO2 emissions,among other issues.There is a need for an environmentally friendly green concrete substitute.Waste products from a variety of sectors can be recycled and used as a green concrete substitute.This decreases the environmental effects of concrete manufacturing as well as energy consumption.The use of solid waste materials for green building is extremely important now and in the future.Green concrete is also in its infancy in terms of manufacturing and application.Academics must intervene by encouraging business implementation.The aim of this review paper is to raise awareness about the importance of repurposing recycled materials and to highlight new technologies for producing green,sustainable concrete.
文摘The clayish crushed stone was used for making aerated concrete. Through studying hydro-thermal synthesis reaction, mix ratio, gas-forming and performance analysis, Grade-B05 and Grade-B06 aerated concrete were prepared successfully. The proper mix ratio and key processing parameters were achieved. The microstructure of aerated concrete with crush stone was analyzed by means of XRD and SEM. The experimental results indicate that the hydration products are poorly crystalline C- S- H ( B ), tobermorite and hydrogarnet. No componeat of clay was found. Unreacted SiO2 cart be in existence, and the structure system of aerated concrete is homogencous and dense.
基金supported by the National Natural Science Foundation of China Project 51868058,52068058Inner Mongolia Natural Science Foundation 2018MS05011Inner Mongolia“Grassland Talent”CYYC5039.
文摘The destruction of concrete building materials in severely cold regions of the north is more severely affected by freeze-thaw cycles,and the relationship between the mechanical properties and pore structure of concrete with fine aggregate from municipal solid waste(MSW)incineration bottom ash after freeze-thaw cycles is analyzed under the degree of freeze-thaw hazard variation.In this paper,the gray correlation method is used to calculate the correlation between the relative dynamic elastic modulus,compressive strength,and microscopic porosity parameters to speculate on the most important factors affecting their changes.The GM(1,1)model was established based on the compressive strength of the waste incineration ash aggregate concrete,the relative error between the simulated and actual values in the model was less than 5%,and the accuracy of the model was level 1,indicating that the GM(1,1)model can well reflect the change in the compressive strength of the MSW incineration bottom ash aggregate concrete during freeze-thaw cycles.Using the gray correlation method,the correlation between the relative dynamic elastic modulus,compressive strength,air content,specific surface area,pore spacing coefficient,and pore average chord length was calculated,and the pore spacing coefficient and pore average chord length were determined to be highly correlated with each other.This determination can help analyze and infer the deterioration mechanism of concrete subject to freeze-thaw cycles.These results can provide a theoretical basis for guiding the engineering practice of concrete with fine aggregates of household bottom ash in the northern cold region.