The influence of steel slag,a by-product from the processing of iron to steel,on the hydration of cement during the hydration process of complex binder was studied by calorimetry,X-ray diffraction analysis,and Ca(OH)2...The influence of steel slag,a by-product from the processing of iron to steel,on the hydration of cement during the hydration process of complex binder was studied by calorimetry,X-ray diffraction analysis,and Ca(OH)2 content determination.The results show that steel slag and cement affect each other’s hydration by changing the hydration environment.Steel slag does not react with the hydration products of cement.The dormant period of cement-steel slag complex binder during the hydration is longer than that of cement.The more the adding amount of steel slag is,the longer the dormant period of complex binder will be.The steel slag decreases the early hydration rate of cement.This phenomenon is more obvious with the increment of steel slag addition.However,the steel slag can promote the hydration degree of cement at later ages and the promoting effect becomes more obvious with the increment of steel slag addition and the hydration ages.展开更多
The initial hydration of steel slag with high Al2O3 content and its influence on the initial hydration of cement were investigated in this study.Steel slag with high Al2O3 content may contain much calcium aluminate mi...The initial hydration of steel slag with high Al2O3 content and its influence on the initial hydration of cement were investigated in this study.Steel slag with high Al2O3 content may contain much calcium aluminate mineral but very little gypsum.The steel slag hydrates much more quickly than cement in the initial hydration period,producing many flake products which have a great influence on the fluidity,initial setting time,and adsorption level of superplasticizer of paste.Replacing part of cement by steel slag with high Al2O3 content can change the hydration condition of calcium aluminate mineral of the cement by decreasing the gypsum to calcium aluminate mineral ratio,resulting in accelerating the hydration rate of calcium aluminate mineral in the initial hydration period.Paste containing steel slag with high Al2O3 content has a shorter initial setting time,higher adsorption level of superplasticizer,and greater loss in fluidity than the pure cement paste.展开更多
This study explores the use of Electric Arc Furnace(EAF)slag as a sustainable alternative raw material in cement clinker production.The research demonstrates the synthesis of ferrite-rich clinker using EAF slag,achiev...This study explores the use of Electric Arc Furnace(EAF)slag as a sustainable alternative raw material in cement clinker production.The research demonstrates the synthesis of ferrite-rich clinker using EAF slag,achieving a clinker composition of 47%alite,32%ferrite,and 20%belite while replacing 20%of clinker raw materials i.e.limestone,iron and silica source.The hydration behavior and influence of carbonation curing on the reactivity of the ferrite phase were assessed.Results show that the addition of 5%gypsum to the clinker enhanced the hydration rate of alite and ferrite phases,promoting the formation of portlandite,C-S-H and ettringite as the major hydration phases.Typical of ferrite-rich cement,Fe/Al-rich siliceous hydrogarnet was also identified as secondary hydration products of the ferrite phase,formed as a result of the reaction of katoite(formed from ferrite dissolution)with dissolved silica.However,prolonged carbonation exposure led to a decrease in the formation of the hydrogarnet and the decomposition of ettringite,but the mortar’s strength increased with increasing calcium carbonate formation.展开更多
基金supported by the Beijing Natural Science Foundation(Grant No.8100001)the National Basic Research Program of China("973"Project)(Grant No.2009CB623106)
文摘The influence of steel slag,a by-product from the processing of iron to steel,on the hydration of cement during the hydration process of complex binder was studied by calorimetry,X-ray diffraction analysis,and Ca(OH)2 content determination.The results show that steel slag and cement affect each other’s hydration by changing the hydration environment.Steel slag does not react with the hydration products of cement.The dormant period of cement-steel slag complex binder during the hydration is longer than that of cement.The more the adding amount of steel slag is,the longer the dormant period of complex binder will be.The steel slag decreases the early hydration rate of cement.This phenomenon is more obvious with the increment of steel slag addition.However,the steel slag can promote the hydration degree of cement at later ages and the promoting effect becomes more obvious with the increment of steel slag addition and the hydration ages.
基金supported by the National Natural Science Foundation of China(Grant No.51108245)the State Key Laboratory of Silicate Materials for Architectures of China(Grant No.SYSJJ2012-10)
文摘The initial hydration of steel slag with high Al2O3 content and its influence on the initial hydration of cement were investigated in this study.Steel slag with high Al2O3 content may contain much calcium aluminate mineral but very little gypsum.The steel slag hydrates much more quickly than cement in the initial hydration period,producing many flake products which have a great influence on the fluidity,initial setting time,and adsorption level of superplasticizer of paste.Replacing part of cement by steel slag with high Al2O3 content can change the hydration condition of calcium aluminate mineral of the cement by decreasing the gypsum to calcium aluminate mineral ratio,resulting in accelerating the hydration rate of calcium aluminate mineral in the initial hydration period.Paste containing steel slag with high Al2O3 content has a shorter initial setting time,higher adsorption level of superplasticizer,and greater loss in fluidity than the pure cement paste.
基金supported by Advanced Steels for the Green Planet-project funded by the Jane and Aatos Erkko and the Tiina and Antti Herlin foundations.Yliniemi would like to acknowledge Academy of Finland(grant number 354263)funded by Business Finland project“Towards Fossil-free Steel 2-FFS 2(5534/31/2023)+2 种基金funded by the UKRI Future Leaders Fellowship(MR/V023829/1)EPSRC project EP/W018810/1,“Developing iron-rich cement clinker&understanding ferrite for the valorisation&upcycling of steel slags(FeRICH)”supported by the UKRI ISCF Industrial Decarbonisation Challenge,through the UK Industrial Decarbonisation Research and Innovation Centre(IDRIC)award number:EP/V027050/1,under the Industrial Decarbonisation Challenge(IDC).
文摘This study explores the use of Electric Arc Furnace(EAF)slag as a sustainable alternative raw material in cement clinker production.The research demonstrates the synthesis of ferrite-rich clinker using EAF slag,achieving a clinker composition of 47%alite,32%ferrite,and 20%belite while replacing 20%of clinker raw materials i.e.limestone,iron and silica source.The hydration behavior and influence of carbonation curing on the reactivity of the ferrite phase were assessed.Results show that the addition of 5%gypsum to the clinker enhanced the hydration rate of alite and ferrite phases,promoting the formation of portlandite,C-S-H and ettringite as the major hydration phases.Typical of ferrite-rich cement,Fe/Al-rich siliceous hydrogarnet was also identified as secondary hydration products of the ferrite phase,formed as a result of the reaction of katoite(formed from ferrite dissolution)with dissolved silica.However,prolonged carbonation exposure led to a decrease in the formation of the hydrogarnet and the decomposition of ettringite,but the mortar’s strength increased with increasing calcium carbonate formation.
