The dynamic viscoelastic properties of asphalt AC-20 and its composites with Organic-Montmorillonite clay (OMMt) and SBS were modeled using the empirical Havriliak-Negami (HN) model, based on linear viscoelastic theor...The dynamic viscoelastic properties of asphalt AC-20 and its composites with Organic-Montmorillonite clay (OMMt) and SBS were modeled using the empirical Havriliak-Negami (HN) model, based on linear viscoelastic theory (LVE). The HN parameters, α, β, G0, G∞and τHN were determined by solving the HN equation across various temperatures and frequencies. The HN model successfully predicted the rheological behavior of the asphalt and its blends within the temperature range of 25˚C - 40˚C. However, deviations occurred between 40˚C - 75˚C, where the glass transition temperature Tg of the asphalt components and the SBS polymer are located, rendering the HN model ineffective for predicting the dynamic viscoelastic properties of composites containing OMMt under these conditions. Yet, the prediction error of the HN model dropped to 2.28% - 2.81% for asphalt and its mixtures at 100˚C, a temperature exceeding the Tg values of both polymer and asphalt, where the mixtures exhibited a liquid-like behavior. The exponent α and the relaxation time increased with temperature across all systems. Incorporating OMMt clay into the asphalt blends significantly enhanced the relaxation dynamics of the resulting composites.展开更多
Many specifications of paving asphalts are closely related to their colloidal stability, which is, however, determined by their exact chemical compositions. The Yumen vacuum residue (YVR), the bottoms of a paraffinic...Many specifications of paving asphalts are closely related to their colloidal stability, which is, however, determined by their exact chemical compositions. The Yumen vacuum residue (YVR), the bottoms of a paraffinic crude oil is unfit for the production of highway paving asphalts directly, Neither are the de-oiled asphalts of the YVR. In this research a blending method and an optimal process of solvent de-asphalts are adopted to investigate the feasibility of formulating highway-paving asphalts from YVR. Results show that highway paving asphalts are formulated by blending solvent de-oiled asphalts with one or more of the materials including YVR, decanted oil from FCC process, and furfural extracts from lubricating base stocks. Further investigations indicate that adding oil decanted from FCC process to the solvent de-asphalting process can increase the de-asphalted oil production, improve the de-oiled asphalts quality, and thus optimize the refinery processes. The methodology of this research can be extended even to refineries processing non-paraffinic crude oils.展开更多
Waste packaging polyethylene（WPE） was used to modify raw asphalt by melt blending the components at 190 ℃ for 1 h in a simple mixer and subsequently machining them at 120 ℃ for 1 h in a highspeed shearing machine....Waste packaging polyethylene（WPE） was used to modify raw asphalt by melt blending the components at 190 ℃ for 1 h in a simple mixer and subsequently machining them at 120 ℃ for 1 h in a highspeed shearing machine.The effect of modification on the degree of the penetration,the softening point and the ductility of the asphalt was studied using fluorescent microscopy,infrared spectrometry,component changes and various other techniques.The experimental results showed that no chemical reactions took place in the components themselves（saturate,aromatic,asphaltene and resin） during the modifications.The softening point and penetration of the asphalt were found to be closely related to the resulting contents of the asphaltene,saturate and resin components.In addition,aromatics were identified as having the greatest impact on the ductility of the asphalt.展开更多
文摘The dynamic viscoelastic properties of asphalt AC-20 and its composites with Organic-Montmorillonite clay (OMMt) and SBS were modeled using the empirical Havriliak-Negami (HN) model, based on linear viscoelastic theory (LVE). The HN parameters, α, β, G0, G∞and τHN were determined by solving the HN equation across various temperatures and frequencies. The HN model successfully predicted the rheological behavior of the asphalt and its blends within the temperature range of 25˚C - 40˚C. However, deviations occurred between 40˚C - 75˚C, where the glass transition temperature Tg of the asphalt components and the SBS polymer are located, rendering the HN model ineffective for predicting the dynamic viscoelastic properties of composites containing OMMt under these conditions. Yet, the prediction error of the HN model dropped to 2.28% - 2.81% for asphalt and its mixtures at 100˚C, a temperature exceeding the Tg values of both polymer and asphalt, where the mixtures exhibited a liquid-like behavior. The exponent α and the relaxation time increased with temperature across all systems. Incorporating OMMt clay into the asphalt blends significantly enhanced the relaxation dynamics of the resulting composites.
文摘Many specifications of paving asphalts are closely related to their colloidal stability, which is, however, determined by their exact chemical compositions. The Yumen vacuum residue (YVR), the bottoms of a paraffinic crude oil is unfit for the production of highway paving asphalts directly, Neither are the de-oiled asphalts of the YVR. In this research a blending method and an optimal process of solvent de-asphalts are adopted to investigate the feasibility of formulating highway-paving asphalts from YVR. Results show that highway paving asphalts are formulated by blending solvent de-oiled asphalts with one or more of the materials including YVR, decanted oil from FCC process, and furfural extracts from lubricating base stocks. Further investigations indicate that adding oil decanted from FCC process to the solvent de-asphalting process can increase the de-asphalted oil production, improve the de-oiled asphalts quality, and thus optimize the refinery processes. The methodology of this research can be extended even to refineries processing non-paraffinic crude oils.
基金Funded in part by the National Natural Science Foundation of China(Nos.51172180 and 51372200)the Program for New Century Excellent Talents in University of Ministry of Education of China(No.NCET-12-1045)+1 种基金the Local Service Program of Shaanxi Provincial Education Department(No.2013JC19)the Excellent Ph D Dissertation Foundation of XAUT(102-211208)
文摘Waste packaging polyethylene（WPE） was used to modify raw asphalt by melt blending the components at 190 ℃ for 1 h in a simple mixer and subsequently machining them at 120 ℃ for 1 h in a highspeed shearing machine.The effect of modification on the degree of the penetration,the softening point and the ductility of the asphalt was studied using fluorescent microscopy,infrared spectrometry,component changes and various other techniques.The experimental results showed that no chemical reactions took place in the components themselves（saturate,aromatic,asphaltene and resin） during the modifications.The softening point and penetration of the asphalt were found to be closely related to the resulting contents of the asphaltene,saturate and resin components.In addition,aromatics were identified as having the greatest impact on the ductility of the asphalt.
