A gas-solids fast separator was studied for its potential application in the process of coal pyrolysis to acetylene in plasma.The CFD method was employed to simulate the flow behavior in the gas-solids fast separator ...A gas-solids fast separator was studied for its potential application in the process of coal pyrolysis to acetylene in plasma.The CFD method was employed to simulate the flow behavior in the gas-solids fast separator based on the realizable k-ε turbulence model and the discrete particle model(DPM).The separation efficiency and residence time of gas phase in the gas-solids fast separator could be calculated.The numerical simulations were validated by the experimental results at a low velocity of the inlet gas(e.g.,4 m·s-1).With the increase of gas velocity at the inlet,the separation efficiency was increased,and the residence time of gas phase was reduced accordingly.The separation efficiency approached 100% when particle diameter was larger than 20 μm.When inlet velocity was 100 m·s-1,the mean residence time of gas phase was about 35 ms.To be noted,the performance of the gas-solids fast separator could be improved,for example by shortening the length of the separator,with a reduced residence time of gas phase at ～20 ms.It is expected that the gas-solids fast separator can meet the stringent demand of the coal pyrolysis to acetylene process for the milliseconds reaction,quench and separation.展开更多
Dynamic characteristics of UV enhanced gas–solid PVC chlorination process were revealed by a UV–Vis spectral online analysis method. Experimental results showed an instantaneous increase of the chlorination rate as ...Dynamic characteristics of UV enhanced gas–solid PVC chlorination process were revealed by a UV–Vis spectral online analysis method. Experimental results showed an instantaneous increase of the chlorination rate as soon as UV light was affiliated, which demonstrated the intensified effect of UV radiation on PVC chlorination directly.Different affiliation methods of UV light were then studied, proving that continuous UV radiation could enhance the chlorination process significantly while intermittent UV radiation was able to initiate the chlorination reaction once it was conducted. Besides, experiments were carried out to study the influences of parameters on the chlorination process such as UV wavelength, chlorination temperature, partial pressure of chlorine gas and PVC raw materials. Among all the parameters, chlorination temperature and partial pressure of chlorine gas were testified as two key factors to determine the chlorination performance. Thermal analysis of CPVC products showed that their corresponding properties such as the glass transition temperature(Tg) and the homogeneity of chlorine distribution in polymer phase were improved with the increase of chlorine content.展开更多
文摘A gas-solids fast separator was studied for its potential application in the process of coal pyrolysis to acetylene in plasma.The CFD method was employed to simulate the flow behavior in the gas-solids fast separator based on the realizable k-ε turbulence model and the discrete particle model(DPM).The separation efficiency and residence time of gas phase in the gas-solids fast separator could be calculated.The numerical simulations were validated by the experimental results at a low velocity of the inlet gas(e.g.,4 m·s-1).With the increase of gas velocity at the inlet,the separation efficiency was increased,and the residence time of gas phase was reduced accordingly.The separation efficiency approached 100% when particle diameter was larger than 20 μm.When inlet velocity was 100 m·s-1,the mean residence time of gas phase was about 35 ms.To be noted,the performance of the gas-solids fast separator could be improved,for example by shortening the length of the separator,with a reduced residence time of gas phase at ～20 ms.It is expected that the gas-solids fast separator can meet the stringent demand of the coal pyrolysis to acetylene process for the milliseconds reaction,quench and separation.
基金Supported by the National Science and Technology Key Supporting Project(2013BAF08B05)the National Natural Science Foundation of China(21176137)
文摘Dynamic characteristics of UV enhanced gas–solid PVC chlorination process were revealed by a UV–Vis spectral online analysis method. Experimental results showed an instantaneous increase of the chlorination rate as soon as UV light was affiliated, which demonstrated the intensified effect of UV radiation on PVC chlorination directly.Different affiliation methods of UV light were then studied, proving that continuous UV radiation could enhance the chlorination process significantly while intermittent UV radiation was able to initiate the chlorination reaction once it was conducted. Besides, experiments were carried out to study the influences of parameters on the chlorination process such as UV wavelength, chlorination temperature, partial pressure of chlorine gas and PVC raw materials. Among all the parameters, chlorination temperature and partial pressure of chlorine gas were testified as two key factors to determine the chlorination performance. Thermal analysis of CPVC products showed that their corresponding properties such as the glass transition temperature(Tg) and the homogeneity of chlorine distribution in polymer phase were improved with the increase of chlorine content.
