Abstract: A tantalum-material multilevel distillation crucible; the distillation crucible comprises a crucible body (1), an insulation plate (2), and a receiving hood (3); the insulation plate (2) is sheathed in the upper part of the crucible body (1), and the receiving cover is disposed on top of the crucible body (1) and above the insulation plate (2); the crucible body (1) is made of tantalum in a horn-shaped circular truncated cone increasing in size from top to bottom; and the insulation plate (2) is made of a high-temperature resistant refractory material with good insulation performance, characterized by: the insulation plate (2) comprises of a plurality of insulation plates that can be stacked and used (2); and a heating unit (6) provided with a plurality of pads (5) that can be stacked and used at the bottom of the crucible.

Abstract: A method of washing anode slime from lead-bismuth alloy electrolysis is disclosed, wherein a lead fluorosilicate solution with high concentration can be obtained by using the anode slime from lead-bismuth alloy electrolysis as raw material, which is characterized in that the method includes the following steps: (1) pretreating the anode slime, (2) primarily soaking the anode slime, (3) secondarily soaking the anode slime. A method of washing anode slime from lead-bismuth alloy electrolysis, and obtaining a soaking solution containing a lot of lead ions and fluorosilicic anions is provided. The soaking supernatant is added directly into the electrolyte-circulating system of lead-bismuth alloy electrolysis, which increases the utilization rate of lead ions and fluorosilicic anions, and improves the environment for smelting bismuth and silver, while reduces production cost for smelting lead, bismuth and silver.

Abstract: A liquid collection process with liquid guiding holes for in-situ leaching an ore body to extract rare earth elements, including: 1) multiple liquid collection channels are provided in an ore body; 2) liquid guiding holes are arranged near the bottom and on both sides of the channels, and these holes and the channels jointly constitute a multi-channel mother liquid drainage and collection control network; 3) a blocking wall is provided in the channels, a front lower part of the wall is connected to a channel outlet by a conduit controlled with a ball valve switch at the outlet; 4) a multi-channel mother liquid collection network of liquid collection engineering control system is finally formed through the alternate operation of pressure release and increase. The process reduces the loss rate of mother liquid, reduces environmental pollution, and improves the recovery rate of rare earth elements.

Abstract: A method for determining the content of calcium element in an ore is provided. It includes: decomposing the ore with hydrochloric acid and nitric acid under heating condition, adding perchloric acid, cooling, adding a small amount of water and boiling the solution to dissolve the salts, then cooling, diluting to the constant volume, filtering into a dry beaker with dry filter-paper, masking interfering ions with triethanolamine, adjusting the pH value of the solution with KOH, using calcein-thymolphthalein as indicator, and determinating the content of calcium with EDTA titrimetry.

Abstract: A process for producing basic lead carbonate is provided. The process comprises: (1) immersing neutralization slag to obtain sodium hydroxide solution; (2) leaching lead chloride slag with the aqueous solution containing sodium chloride and hydrochloric acid, adding sodium sulfide and filtering; (3) neutralizing the filtrate with sodium hydroxide solution, filtering and washing the precipitate; and (4) converting the precipitate to basic lead carbonate with ammonium bicarbonate, crystallizing and washing. Said neutralization slag and lead chloride slag are the redundant slag from fire refining bismuth. Said process makes better use of the redundant slag from fire refining bismuth, saves resources and reduces environmental pollution.