Gypsum sludge,a hazardous waste generated by the non-ferrous smelting industry,presents a significant challenge for disposal and utilization.To investigate the feasibility of substituting gypsum sludge for limestone a...Gypsum sludge,a hazardous waste generated by the non-ferrous smelting industry,presents a significant challenge for disposal and utilization.To investigate the feasibility of substituting gypsum sludge for limestone as a flux for smelting,the effects of calcium sulfate(CaSO_(4))and smelting conditions on oxygen-rich smelting of lead concentrate were studied.The interaction between CaSO_(4)and sulfides facilitates the conversion of CaSO_(4)into CaO,which is crucial for slag formation.The order of the influence of sulfide minerals on the conversion of CaSO_(4)is pyrite>sphalerite>galena.When using gypsum sludge exclusively as the calcium source,under optimal conditions with a CaO/SiO_(2)mass ratio of 0.8,an FeO/SiO_(2)mass ratio of 1.2,a melting temperature of 1150℃,an oxygen flow rate of 1.3 L/min,the recovery rates of Pb and Zn in the lead-rich slag reached 85.01%and 95.69%,respectively,with a sulfur content of 2.65 wt%.The As content in the smelting slag obtained by reduction smelting was 0.02 wt%.Resource utilization of gypsum sludge in lead smelting is a feasible method.展开更多
Water resource allocation was defined as an input-output question in this paper, and a preliminary input-output index system was set up. Then GEM （group eigenvalue method）-MAUE （multi-attribute utility theory） mod...Water resource allocation was defined as an input-output question in this paper, and a preliminary input-output index system was set up. Then GEM （group eigenvalue method）-MAUE （multi-attribute utility theory） model was applied to evaluate relative efficiency of water resource allocation plans. This model determined weights of indicators by GEM, and assessed the allocation schemes by MAUE. Compared with DEA （Data Envelopment Analysis） or ANN （Artificial Neural Networks）, the mode was more applicable in some cases where decision-makers had preference for certain indicators展开更多
In the base of utility and marginal utility,the article put forwardthe concept of utility and marginal utilityof educational outlay and the theory of them,and analyzed the actuality of educational resource deployment ...In the base of utility and marginal utility,the article put forwardthe concept of utility and marginal utilityof educational outlay and the theory of them,and analyzed the actuality of educational resource deployment in ourcountry,gave some advice about howtoi mprove our educational resource deployment of compulsory education.展开更多
The major faced problems at present in Yangtze river basin are: ① uneffective control in river water pollution threatens seriously the safety of drinking water; ② shrinkage of lake area and serious eutrophication; ...The major faced problems at present in Yangtze river basin are: ① uneffective control in river water pollution threatens seriously the safety of drinking water; ② shrinkage of lake area and serious eutrophication; ③ soil-water losses degraded the ecological environment of the basin; ④ the impact of TGP and S-N water transfer project on water environment of the basin. In the light of above-mentioned problems, water resources utilization strategy must be adjusted and the sustainable social and economic development should be supported by sustainable water resources utilization, and it is necessary to take the following countermeasures: ① establishing overall flood control and disaster relief system; ② developing high water use efficiency agriculture; ③ taking "giving priority to water saving on the basis of pollution control" as urban water resources utilization strategy; ④ implementing comprehensive pollution control strategy with sources control as main point; ⑤ guaranteing water demand of the ecological environment; ⑥implementing the strategy of maintaining water resources supply and demand balance on the basis of water demand management; ⑦ studying countermeasures for the ecological and environmental impacts of trans-basin water transfer and western China devolopment. The key of realization of sustainable water resources utilization is to reform management and investment mechanism of water resources and water price policy. It is the only way to solve the water resources problems in Yangtze river basin as well as the whole China.展开更多
基金Project(2020YFC1909203)supported by the National Key R&D Project of ChinaProjects(51974364,52074355,51904339)supported by the National Natural Science Foundation of China。
文摘Gypsum sludge,a hazardous waste generated by the non-ferrous smelting industry,presents a significant challenge for disposal and utilization.To investigate the feasibility of substituting gypsum sludge for limestone as a flux for smelting,the effects of calcium sulfate(CaSO_(4))and smelting conditions on oxygen-rich smelting of lead concentrate were studied.The interaction between CaSO_(4)and sulfides facilitates the conversion of CaSO_(4)into CaO,which is crucial for slag formation.The order of the influence of sulfide minerals on the conversion of CaSO_(4)is pyrite>sphalerite>galena.When using gypsum sludge exclusively as the calcium source,under optimal conditions with a CaO/SiO_(2)mass ratio of 0.8,an FeO/SiO_(2)mass ratio of 1.2,a melting temperature of 1150℃,an oxygen flow rate of 1.3 L/min,the recovery rates of Pb and Zn in the lead-rich slag reached 85.01%and 95.69%,respectively,with a sulfur content of 2.65 wt%.The As content in the smelting slag obtained by reduction smelting was 0.02 wt%.Resource utilization of gypsum sludge in lead smelting is a feasible method.
文摘Water resource allocation was defined as an input-output question in this paper, and a preliminary input-output index system was set up. Then GEM （group eigenvalue method）-MAUE （multi-attribute utility theory） model was applied to evaluate relative efficiency of water resource allocation plans. This model determined weights of indicators by GEM, and assessed the allocation schemes by MAUE. Compared with DEA （Data Envelopment Analysis） or ANN （Artificial Neural Networks）, the mode was more applicable in some cases where decision-makers had preference for certain indicators
文摘In the base of utility and marginal utility,the article put forwardthe concept of utility and marginal utilityof educational outlay and the theory of them,and analyzed the actuality of educational resource deployment in ourcountry,gave some advice about howtoi mprove our educational resource deployment of compulsory education.
文摘The major faced problems at present in Yangtze river basin are: ① uneffective control in river water pollution threatens seriously the safety of drinking water; ② shrinkage of lake area and serious eutrophication; ③ soil-water losses degraded the ecological environment of the basin; ④ the impact of TGP and S-N water transfer project on water environment of the basin. In the light of above-mentioned problems, water resources utilization strategy must be adjusted and the sustainable social and economic development should be supported by sustainable water resources utilization, and it is necessary to take the following countermeasures: ① establishing overall flood control and disaster relief system; ② developing high water use efficiency agriculture; ③ taking "giving priority to water saving on the basis of pollution control" as urban water resources utilization strategy; ④ implementing comprehensive pollution control strategy with sources control as main point; ⑤ guaranteing water demand of the ecological environment; ⑥implementing the strategy of maintaining water resources supply and demand balance on the basis of water demand management; ⑦ studying countermeasures for the ecological and environmental impacts of trans-basin water transfer and western China devolopment. The key of realization of sustainable water resources utilization is to reform management and investment mechanism of water resources and water price policy. It is the only way to solve the water resources problems in Yangtze river basin as well as the whole China.
