To satisfy the requirement on the separation of solid and liquid in waste drilling mud, prepare a high effective floccu-lant for high density waste drilling mud used starch, 2-Trimethylammonium ethyl methacrylate chlo...To satisfy the requirement on the separation of solid and liquid in waste drilling mud, prepare a high effective floccu-lant for high density waste drilling mud used starch, 2-Trimethylammonium ethyl methacrylate chloride (DMC) and acrylamide (AM). The result showed that when the ratio of starch, DMC and AM was 2:1:3, the weight of initiator (po-tassium persulfate) was 0.2% of the AM, reaction temperature was 65℃ and reaction time was 5h, the performance of product was the best. The water content in filter cake was 27.6% after the waste drilling mud disposed by the optimization flocculant. The flocculent effect of optimization flocculant was superior to that of other flocculant in market.展开更多
This paper presents a paleoflood study to determine the flood frequency of the Changjiang River, based on core cj0702, taken from the Changjiang River subaqueous delta. We identified flood deposits by means of high-re...This paper presents a paleoflood study to determine the flood frequency of the Changjiang River, based on core cj0702, taken from the Changjiang River subaqueous delta. We identified flood deposits by means of high-resolution grain-size variation, sensitive population, geochemical indexes and magnetic susceptibility. The core covers a time span of 120 years by 210 Pb dating and was sampled at 1–2 cm intervals. Grain size, geochemical elements, and physical parameters were analyzed. The results indicate that the sediment of the core is mainly composed of silt and clay, as well as groups of interbedded silt, clay silt, and clay. Vertically, the grain size pattern was controlled by seasonal variations in water discharge and by the sediment input in winter from the abandoned Huanghe River delta. River flooding caused extreme values in all our measured parameters. We identified more than 20 flood events that occurred since 1887 using the physical parameter analysis method. The environmentally sensitive component of sediment grain size(14.32–96.39 μm) contribution>30%, Zr/Rb ratio>1.5, and magnetic susceptibility>16 were selected as the criteria for flood identification generally. We also found that floods that had taken place in the upstream, midstream, or downstream parts of the river were clearly identified by these indexes while the large-scale floods that covered the whole drainage area did not leave clear indications in the sediment record. This study for identification of flood events is of great significance for understanding hyperpycnal current sedimentation as well as for forecasting of floods.展开更多
Red mud has relatively small solid particles(d50=13.02μm)and will flow in paste form under high pressure during pipe- line transport.Red mud belongs to a two-phase flow of materials with high viscosity and a high con...Red mud has relatively small solid particles(d50=13.02μm)and will flow in paste form under high pressure during pipe- line transport.Red mud belongs to a two-phase flow of materials with high viscosity and a high concentration of non-sedimentation,homogeneous solid-liquids.It is difficult to test its rheological properties under atmospheric pressure.Measurements such as rota- tional viscometry can not reflect the real state of the material when it is flowing in a pipe.Tested rheological parameters are some- what higher than the actual values.In our investigation,grain shape,distinctive modality and grain size distribution of red mud were tested.Based on the principle of tube measurement,rheological experiments on red mud at different concentrations were car- ried out by using our independently developed tube-type pressure rheology test facility,and obtained constitutive equations.We conclude that red mud behaves as non-Newtonian pseudo-plastic fluid in pipe flows.Its consistency and power-law indices vary considerably with different concentrations.展开更多
A great amount of red mud generated from alumina production by Bayer process not only threatens the environment but also causes waste of secondary resources.High-iron-content red mud from Bayer process was employed to...A great amount of red mud generated from alumina production by Bayer process not only threatens the environment but also causes waste of secondary resources.High-iron-content red mud from Bayer process was employed to recover alumina and ferric oxide by the process of reduction-sintering,leaching and then magnetic beneficiation.Results of thermodynamic analyses show that ferric oxide should be reduced to Fe if reduction of ferric oxide and formation of sodium aluminate and calcium silicate happen simultaneously.Experimental results indicate that alumina recovery of Bayer red mud can reach 89.71%,and Fe recovery rate and the grade of magnetite concentrate are 60.67%and 61.78%,respectively,under the optimized sintering conditions.展开更多
To satisfy the requirement on solid-liquid separation in high-density waste drilling mud, prepare the nano-modified polyacrylamide(PAM) flocculant for high density waste drilling mud by in-situ dispersion method, dire...To satisfy the requirement on solid-liquid separation in high-density waste drilling mud, prepare the nano-modified polyacrylamide(PAM) flocculant for high density waste drilling mud by in-situ dispersion method, direct dispersion method and simultaneous formation method. The result showed the flocculent effect of nano-modified polyacrylamide prepared by simultaneous formation method was the best. When the content of water glass and acrylamide(AM) were respectively 3% and 15% , reaction temperature was 60?C and reaction time was 3h, the performance of product was the best. The water content in filter cake was 24.32% after the waste drilling mud disposed by the optimization flocculant. The flocculent effect of optimization flocculant was superior to that of other flocculant in market.展开更多
文摘To satisfy the requirement on the separation of solid and liquid in waste drilling mud, prepare a high effective floccu-lant for high density waste drilling mud used starch, 2-Trimethylammonium ethyl methacrylate chloride (DMC) and acrylamide (AM). The result showed that when the ratio of starch, DMC and AM was 2:1:3, the weight of initiator (po-tassium persulfate) was 0.2% of the AM, reaction temperature was 65℃ and reaction time was 5h, the performance of product was the best. The water content in filter cake was 27.6% after the waste drilling mud disposed by the optimization flocculant. The flocculent effect of optimization flocculant was superior to that of other flocculant in market.
基金Supported by the National Natural Science Foundation of China(Nos.41206073,41376079,41206051,41206052)the China Geological Survey(Nos.1212010611401,200900501)
文摘This paper presents a paleoflood study to determine the flood frequency of the Changjiang River, based on core cj0702, taken from the Changjiang River subaqueous delta. We identified flood deposits by means of high-resolution grain-size variation, sensitive population, geochemical indexes and magnetic susceptibility. The core covers a time span of 120 years by 210 Pb dating and was sampled at 1–2 cm intervals. Grain size, geochemical elements, and physical parameters were analyzed. The results indicate that the sediment of the core is mainly composed of silt and clay, as well as groups of interbedded silt, clay silt, and clay. Vertically, the grain size pattern was controlled by seasonal variations in water discharge and by the sediment input in winter from the abandoned Huanghe River delta. River flooding caused extreme values in all our measured parameters. We identified more than 20 flood events that occurred since 1887 using the physical parameter analysis method. The environmentally sensitive component of sediment grain size(14.32–96.39 μm) contribution>30%, Zr/Rb ratio>1.5, and magnetic susceptibility>16 were selected as the criteria for flood identification generally. We also found that floods that had taken place in the upstream, midstream, or downstream parts of the river were clearly identified by these indexes while the large-scale floods that covered the whole drainage area did not leave clear indications in the sediment record. This study for identification of flood events is of great significance for understanding hyperpycnal current sedimentation as well as for forecasting of floods.
文摘Red mud has relatively small solid particles(d50=13.02μm)and will flow in paste form under high pressure during pipe- line transport.Red mud belongs to a two-phase flow of materials with high viscosity and a high concentration of non-sedimentation,homogeneous solid-liquids.It is difficult to test its rheological properties under atmospheric pressure.Measurements such as rota- tional viscometry can not reflect the real state of the material when it is flowing in a pipe.Tested rheological parameters are some- what higher than the actual values.In our investigation,grain shape,distinctive modality and grain size distribution of red mud were tested.Based on the principle of tube measurement,rheological experiments on red mud at different concentrations were car- ried out by using our independently developed tube-type pressure rheology test facility,and obtained constitutive equations.We conclude that red mud behaves as non-Newtonian pseudo-plastic fluid in pipe flows.Its consistency and power-law indices vary considerably with different concentrations.
基金Project(2005CB623702)supported by the National Basic Research Program of China
文摘A great amount of red mud generated from alumina production by Bayer process not only threatens the environment but also causes waste of secondary resources.High-iron-content red mud from Bayer process was employed to recover alumina and ferric oxide by the process of reduction-sintering,leaching and then magnetic beneficiation.Results of thermodynamic analyses show that ferric oxide should be reduced to Fe if reduction of ferric oxide and formation of sodium aluminate and calcium silicate happen simultaneously.Experimental results indicate that alumina recovery of Bayer red mud can reach 89.71%,and Fe recovery rate and the grade of magnetite concentrate are 60.67%and 61.78%,respectively,under the optimized sintering conditions.
文摘To satisfy the requirement on solid-liquid separation in high-density waste drilling mud, prepare the nano-modified polyacrylamide(PAM) flocculant for high density waste drilling mud by in-situ dispersion method, direct dispersion method and simultaneous formation method. The result showed the flocculent effect of nano-modified polyacrylamide prepared by simultaneous formation method was the best. When the content of water glass and acrylamide(AM) were respectively 3% and 15% , reaction temperature was 60?C and reaction time was 3h, the performance of product was the best. The water content in filter cake was 24.32% after the waste drilling mud disposed by the optimization flocculant. The flocculent effect of optimization flocculant was superior to that of other flocculant in market.
