According to the physical and chemical characteristics of superfine powder extinguishing agent,three test methods are selected to measure the flow ability.By studying and comparing various test methods,apparatus and c...According to the physical and chemical characteristics of superfine powder extinguishing agent,three test methods are selected to measure the flow ability.By studying and comparing various test methods,apparatus and conditions,the optimum method and conditions to test flow property of superfine powder extinguishing agent are confirmed.展开更多
To improve the flow ability of crude oil with high content of aromatic asphaltenes,new comb-type copolymers of poly(maleic anhydride-co-α-olefin-costyrene)(MASCs)with different ratios of maleic anhydride(MA)to styren...To improve the flow ability of crude oil with high content of aromatic asphaltenes,new comb-type copolymers of poly(maleic anhydride-co-α-olefin-costyrene)(MASCs)with different ratios of maleic anhydride(MA)to styrene were designed and synthesized.1H NMR and FTIR spectra were used to characterize the chemical structure of the copolymers.The effect of copolymers on the flow ability of model waxy oil and crude oil were studied by rheological method and polarizing light microscopy.Upon the addition of MASCs,the yield stresses of oils were decreased by 1 to 3 orders of magnitude,and the morphology of paraffin crystals were reduced and changed from plates to needles.展开更多
Gel point or pour point is widely used to evaluate the low temperature flowability of crude oil. However, it is not adequate to describe the gelling properties of waxy crude oils under flow conditions with gel point o...Gel point or pour point is widely used to evaluate the low temperature flowability of crude oil. However, it is not adequate to describe the gelling properties of waxy crude oils under flow conditions with gel point or pour point, since the theological behavior of crude oils is dependent on shear history. Waxy crude oils tend to gel at a low temperature. Based on gelation theory, the characteristic temperature of waxy crude oil was determined by analyzing viscosity-temperature data. Two mathematical models were developed for calculating characteristic temperatures of virgin crude oils and pour point depressants （PPD） beneficiated crude oils, respectively. By using these two models, the characteristic temperatures of crude oils that have experienced shearing and thermal histories can be predicted. The model for predicting the characteristic temperature of virgin crude oils has an average relative deviation of 4.5%, and all predicted values have a deviation within 2 ℃. Tested by 42 sets of data, the prediction model for crude oil treated with PPD has a high accuracy, with an average relative deviation of 4.2%, and 95.2 percent of predicted values have a deviation within 2 ℃. These two models provide useful ways for predicting the flowability of crude oils in pipelines when only wax content, wax appearance point and gel point are available.展开更多
A new calcium aluminate cement CA-670 was studied in the system of tabular alumina, white fused alumina （WFA）, and bauxite based low cement castables. The flow ability, strength development, and hot strength （ HMOR...A new calcium aluminate cement CA-670 was studied in the system of tabular alumina, white fused alumina （WFA）, and bauxite based low cement castables. The flow ability, strength development, and hot strength （ HMOR ） were investigated. Different types of additives were used for the CA-670 bonded castables. The results show CA-670 provides a good workability for each type of＂ castables. CA-670 displays a good compatibility with different types of additives. Testing on different batches of CA-670 shows good reproducible properties in each castable, which manifests good consistency and reliability of CA-670.展开更多
文摘According to the physical and chemical characteristics of superfine powder extinguishing agent,three test methods are selected to measure the flow ability.By studying and comparing various test methods,apparatus and conditions,the optimum method and conditions to test flow property of superfine powder extinguishing agent are confirmed.
基金Financial support by the Science Foundation for the Excellent Youth Scholars of East China University of Science and Technology is gratefully acknowledged.
文摘To improve the flow ability of crude oil with high content of aromatic asphaltenes,new comb-type copolymers of poly(maleic anhydride-co-α-olefin-costyrene)(MASCs)with different ratios of maleic anhydride(MA)to styrene were designed and synthesized.1H NMR and FTIR spectra were used to characterize the chemical structure of the copolymers.The effect of copolymers on the flow ability of model waxy oil and crude oil were studied by rheological method and polarizing light microscopy.Upon the addition of MASCs,the yield stresses of oils were decreased by 1 to 3 orders of magnitude,and the morphology of paraffin crystals were reduced and changed from plates to needles.
文摘Gel point or pour point is widely used to evaluate the low temperature flowability of crude oil. However, it is not adequate to describe the gelling properties of waxy crude oils under flow conditions with gel point or pour point, since the theological behavior of crude oils is dependent on shear history. Waxy crude oils tend to gel at a low temperature. Based on gelation theory, the characteristic temperature of waxy crude oil was determined by analyzing viscosity-temperature data. Two mathematical models were developed for calculating characteristic temperatures of virgin crude oils and pour point depressants （PPD） beneficiated crude oils, respectively. By using these two models, the characteristic temperatures of crude oils that have experienced shearing and thermal histories can be predicted. The model for predicting the characteristic temperature of virgin crude oils has an average relative deviation of 4.5%, and all predicted values have a deviation within 2 ℃. Tested by 42 sets of data, the prediction model for crude oil treated with PPD has a high accuracy, with an average relative deviation of 4.2%, and 95.2 percent of predicted values have a deviation within 2 ℃. These two models provide useful ways for predicting the flowability of crude oils in pipelines when only wax content, wax appearance point and gel point are available.
文摘A new calcium aluminate cement CA-670 was studied in the system of tabular alumina, white fused alumina （WFA）, and bauxite based low cement castables. The flow ability, strength development, and hot strength （ HMOR ） were investigated. Different types of additives were used for the CA-670 bonded castables. The results show CA-670 provides a good workability for each type of＂ castables. CA-670 displays a good compatibility with different types of additives. Testing on different batches of CA-670 shows good reproducible properties in each castable, which manifests good consistency and reliability of CA-670.
