A lot of mixed clay-resin waste sand from large-scale iron foundries is discharged every day; so mixed waste sand reclamation in low cost and high quality has a great realistic significance. In the study to investigat...A lot of mixed clay-resin waste sand from large-scale iron foundries is discharged every day; so mixed waste sand reclamation in low cost and high quality has a great realistic significance. In the study to investigate the possibility of reusing two types of waste foundry sands, resin bonded sand and clay bonded sand which came from a Chinese casting factory, a new low-cost reclamation method of the mixed foundry waste sand based on the wet-thermal composite reclamation was proposed. The waste resin bonded sand was first reclaimed by a thermal method and the waste clay bonded sand was reclaimed by a wet method. Then, hot thermal reclaimed sand and the dehydrated wet reclaimed sand were mixed in certain proportions so that the hot thermal reclaimed sand dried the wet reclaimed sand leaving some water. The thermal reclamation efficiency of the waste resin bonded sand was researched at different heat levels. The optimized wet reclamation process of the waste clay bonded sand was achieved by investigating the effects of wet reclamation times, sand-water ratio and pH value on the reclaimed sand characteristics. The composite reclamation cost also was calculated. The research results showed that the properties of the mixed reclaimed sand can satisfy the application requirements of foundries; in which the temperature of the thermal reclamation waste resin bonded sand needs to be about 800 oC, the number of cycles of wet reclamation waste clay bonded sand should reach four to five, the optimal sand-water ratio of wet reclamation is around 1:1.5, and the pH value should be adjusted by adding acid. The mass ratio of hot thermal reclaimed sand to dehydrated wet reclaimed sand is about 1:2.5, and the composite reclaimed sand cost is around 100 yuan RMB per ton.展开更多
江西某白钨矿在“双碳”背景下,围绕节能减排和节约土地(林地)资源为目的进行选矿试验研究,通过采用XRT分选粗抛废石、螺旋溜槽+摇床分级重选抛尾砂,实现粗抛早抛,废石、尾砂总产率为87.67%,WO_(3)品位降为0.04%,粗抛早抛可以降低选矿...江西某白钨矿在“双碳”背景下,围绕节能减排和节约土地(林地)资源为目的进行选矿试验研究,通过采用XRT分选粗抛废石、螺旋溜槽+摇床分级重选抛尾砂,实现粗抛早抛,废石、尾砂总产率为87.67%,WO_(3)品位降为0.04%,粗抛早抛可以降低选矿作业能耗30%左右,粗抛早抛效果显著。摇床精矿和细泥采用浮选工艺进行选别,获得的选矿指标(全矿)为:钨精矿1产率0.31%、WO_(3)品位75.20%、WO_(3)回收率为56.32%,钨精矿2产率0.18%、WO_(3)品位46.10%、WO_(3)回收率为20.05%,WO_(3)总回收率达76.37%,选矿效果良好。对粗抛早抛的废石和尾砂进行综合利用分析,废石满足建筑用碎石要求,尾砂满足机制砂特细砂要求。经估算,对废石和尾砂进行综合利用,大约节约土地(林地)16公顷,节约陆地碳汇1684.64 t C,“双碳”效果明显。展开更多
基金supported by the National Natural Science Foundation (Grant numbers:50575085,51075163 and 51375187)
文摘A lot of mixed clay-resin waste sand from large-scale iron foundries is discharged every day; so mixed waste sand reclamation in low cost and high quality has a great realistic significance. In the study to investigate the possibility of reusing two types of waste foundry sands, resin bonded sand and clay bonded sand which came from a Chinese casting factory, a new low-cost reclamation method of the mixed foundry waste sand based on the wet-thermal composite reclamation was proposed. The waste resin bonded sand was first reclaimed by a thermal method and the waste clay bonded sand was reclaimed by a wet method. Then, hot thermal reclaimed sand and the dehydrated wet reclaimed sand were mixed in certain proportions so that the hot thermal reclaimed sand dried the wet reclaimed sand leaving some water. The thermal reclamation efficiency of the waste resin bonded sand was researched at different heat levels. The optimized wet reclamation process of the waste clay bonded sand was achieved by investigating the effects of wet reclamation times, sand-water ratio and pH value on the reclaimed sand characteristics. The composite reclamation cost also was calculated. The research results showed that the properties of the mixed reclaimed sand can satisfy the application requirements of foundries; in which the temperature of the thermal reclamation waste resin bonded sand needs to be about 800 oC, the number of cycles of wet reclamation waste clay bonded sand should reach four to five, the optimal sand-water ratio of wet reclamation is around 1:1.5, and the pH value should be adjusted by adding acid. The mass ratio of hot thermal reclaimed sand to dehydrated wet reclaimed sand is about 1:2.5, and the composite reclaimed sand cost is around 100 yuan RMB per ton.
文摘江西某白钨矿在“双碳”背景下,围绕节能减排和节约土地(林地)资源为目的进行选矿试验研究,通过采用XRT分选粗抛废石、螺旋溜槽+摇床分级重选抛尾砂,实现粗抛早抛,废石、尾砂总产率为87.67%,WO_(3)品位降为0.04%,粗抛早抛可以降低选矿作业能耗30%左右,粗抛早抛效果显著。摇床精矿和细泥采用浮选工艺进行选别,获得的选矿指标(全矿)为:钨精矿1产率0.31%、WO_(3)品位75.20%、WO_(3)回收率为56.32%,钨精矿2产率0.18%、WO_(3)品位46.10%、WO_(3)回收率为20.05%,WO_(3)总回收率达76.37%,选矿效果良好。对粗抛早抛的废石和尾砂进行综合利用分析,废石满足建筑用碎石要求,尾砂满足机制砂特细砂要求。经估算,对废石和尾砂进行综合利用,大约节约土地(林地)16公顷,节约陆地碳汇1684.64 t C,“双碳”效果明显。
