238 results about "Lead bismuth" patented technology

The invention belongs to the technical field of nuclear reactor engineering, and in particular relates to a thermally-operated conversion system which adopts lead or lead-bismuth alloy intermediate loops. The system comprises three loops; a first loop comprises a cold pool, a main pump, a reactor core, a thermal pool and an intermediate heat exchanger arranged in a main container and connected in sequence; a second loop comprises a second loop circulating pump, the intermediate heat exchanger and a steam generator connected in sequence; a third loop comprises a water supplying pump, the steam generator and a steam turbine connected in sequence; a working medium of the first loop is liquid metallic sodium, a working medium of the second loop is liquid metallic lead or a liquid lead-bismuth alloy, and the third loop is a conventional water-steam loop. By adopting the system disclosed by the invention, heat generated by the reactor core can be safely and efficiently brought out of a reactor, so that high-temperature steam is generated in the steam generator and used for pushing the steam turbine to apply work, and heat energy generated by the reactor is converted into mechanical energy.

The invention relates to a method for recovering valuable metals from copper anode mud flotation tailings and belongs to the technical field of thermometallurgy. The method comprises: firstly, performing retailoring on the copper anode mud flotation tailings to obtain a reduction product, and then performing oxidative blowing on the reduction product to obtain rich lead and arsenic and antimony containing soot; first-stage low-temperature vacuum distillation: performing primary low-temperature vacuum distillation on the obtained rich lead under the conditions of a temperature of 400-700 DEG C and a pressure of 1-100Pa for 1-3h, thereby obtaining secondary rich lead and a selenium-tellurium alloy; and second-stage high-temperature vacuum distillation: performing primary high-temperature vacuum distillation on the obtained secondary rich lead under the conditions of a temperature of 800-1200 DEG C and a pressure of 1-100Pa for 1-3h, thereby obtaining a lead-bismuth and a copper-gold-silver alloy. The method for recovering valuable metals from copper anode mud flotation tailings is safe and controllable in whole process flow, simple and convenient to operate, simple in equipment needed, free from three-waste emissions, and environment-friendly.

The invention relates to a method for recovering bismuth from bismuth slag, which includes steps of: firstly, smelting silver-refining converter oxidizing slag in high-temperature restoring mode to obtain lead-bismuth alloy, performing silico-fluoric acid system lead-bismuth alloy electrolysis to obtain electric lead products and high-bismuth anode mud; secondly performing hydrochloric acid leaching on the high-bismuth anode mud, filtering to obtain bismuth-contained leaching liquid, wherein the leaching condition is that: liquid-solid ratio (weight ratio) is 3-6:1, process temperature is 40-70 DEG C, hydrochloric acid concentration is 150-200g / L, and reaction time is1.5-2.5h; and thirdly, replacing bismuth in the leaching liquid through reduced iron powder to obtain sponge bismuth and obtain refined bismuth with high purity in pyro-refining electrolysis. Sodium sulfide for sedimenting silver is added in the leaching process to obtain bismuth leaching liquid, silver can be prevented from immersing into the liquid as much as possible, when return washing liquid is used for leaching high-bismuth anode mud, a part of hydrochloric acid is refilled to maintain necessary potential of hydrogen (pH) value, concentration of Cl- is controlled to be 150-200g / L, and simultaneously bismuth ion hydrolysis can be avoided. Compared with the prior art, the method has no operations of water quenching, ball milling, hydrolysis, neutralization and the like of coarse bismuth alloy, has less procedures, is low in cost and free of pollution, simultaneously achieves double-metal electrolysis of the lead-bismuth alloy and does not influence the electric-lead main system.

The invention relates to a process for recovering silver, lead and bismuth from silver-bearing soot comprehensively, and belongs to the technical field of comprehensive recovery of noble metals. The process comprises the following steps of: removing chlorine from silver soot by using clear water, and performing acid leaching on the silver in the silver soot by using sulfuric acid and an oxidizing agent; adding sodium chloride into silver-bearing solution to obtain pure silver chloride, and performing the conversion of hydrochloric acid, iron powder metathesis and the washing of acidized purified water on the silver chloride to obtain high-purity sponge silver; after the silver is precipitated, purifying solution, removing impurities and crystallizing to obtain zinc sulfate heptahydrate; and smelting the lead and bismuth which are left in lead bismuth dregs to form a lead bismuth alloy by reverberatory furnace, electrolyzing to obtain precipitated lead and bismuth-bearing anode mud, and refining the bismuth-bearing anode mud and removing impurities to obtain refined bismuth. The process is suitable for processing the silver-bearing soot of which the silver content is over 0.8 percent; and compared with the prior art, the process has the advantages of environment friendliness, silver direct yield of more than or equal to 99.2 percent, high recovery rate, low machining cost and quick capital turnover.

The invention discloses a natural circulation loop system of a lead-bismuth alloy. The system comprises a storage tank, a first subchannel, a visual pipeline, a rising pipeline, a condenser, a water pump, a top pipeline, a descending pipeline, a second subchannel and an electric-heating section. The system has the characteristics of being simple in structure and simple and convenient to operate. Based on the secondary heat exchange of the condenser and the electric-heating section, the heat exchange effect of the system is good; pressure gauges and temperature instruments are arranged on all the pipelines of the system while the pipelines are controlled by a valve, so that the safety coefficient of the system is high; the cooling in nuclear industry is carried out by a natural circulation loop, so that the heat energy generated by the nuclear industry is utilized effectively, i.e., the waste of energy sources is avoided. The system not only can be applied to the nuclear industry but also can be applied to scientific research. As a result, the system disclosed by the invention can serve as a practical tool and a scientific-research tool simultaneously.

The invention provides a liquid-state lead bismuth alloy corrosion resisting coating layer and a preparation method thereof and relates to the technical field of material surface treatment. The liquid-state lead bismuth alloy corrosion resisting coating layer comprises a matrix, a coating layer body and a thermally-growing oxide layer, wherein the coating layer body is attached to the surface of the matrix, the thermally-growing oxide layer is attached to the surface of the coating layer body, and the coating layer body is prepared from a material of FeCrAlY. The preparation method of the liquid-state lead bismuth alloy corrosion resisting coating layer comprises the steps: preparing the coating layer body on the surface of the pretreated matrix and then directly performing pre-oxidation treatment on the coating layer body. The FeCrAlY coating layer body of the liquid-state lead bismuth alloy corrosion resisting coating layer disclosed by the invention has good combination with the matrix; the liquid-state lead bismuth alloy corrosion resisting coating layer has the advantages of compact structure, even and controllable thickness, low oxygen content and low surface roughness; pre-oxidation is directly performed on the surface of the coating layer body to in situ generate an even, continuous and compact thermally-growing oxide layer, the thermally-growing oxide layer can directly contact a lead bismuth cooling agent for a long time, and liquid-state lead bismuth alloy corrosion resistance of the coating layer body is improved; a preparation process has the advantages of lowcost, high, efficiency, greenness, environmental friendliness and the like.

The invention relates to a method for preparing a lead bismuth alloy for a nuclear reactor. In the method, the lead bismuth alloy is smelted by vacuum induction. The method comprises the following steps of: 1) putting lead serving as a raw material into a crucible in a glove box, heating to the temperature of between 450 and 800 DEG C, and introducing high-purity hydrogen for pretreatment; 2) passivating the crucible; 3) charging according to design ingredients, cooling the lead, putting into the crucible, and putting bismuth into a hopper; 4) introducing mixed gas of argon and the hydrogen under vacuum of between 0.1 and 10Pa until the mixed gas has the pressure of between 0.01 and 0.5Mpa, and melting at the temperature of between 400 and 600 DEG C, wherein the content of the hydrogen is between 2 and 7 volume percent; 5) adding the bismuth serving as a raw material in batch, and stirring in an electromagnetic and mechanical stirring combination mode; 6) detecting alloy ingredients by using a direct-reading spectrometer, and supplementing alloy elements according to a test result; and 7) pouring at the temperature of between 200 and 400 DEG C under the vacuum after the ingredients are qualified. By the method, the ingredients and purity of the produced lead bismuth alloy meet design requirements, and ingredient segregation and tissue segregation are prevented; the method is suitable for the nuclear reactor; and a process has the characteristics of short production time, high repeatability and low production cost and is easy to operate.

The invention discloses a lead bismuth alloy bubble pump circulation capability experiment system and an experiment method. The system comprises a lead bismuth alloy storing and melting module composed of a lead bismuth alloy storing tank, a liquid level probe, a valve and a pipeline connected to a lead bismuth experiment loop, a gas module composed of an argon bottle, a flow meter, a pressure gauge, a valve and a pipeline connected to the lead bismuth alloy storing tank and an experiment section, an electromagnetic flow meter calibration module composed of an electromagnetic flow meter, a checking cylinder, a liquid level probe and a valve, and an experiment module composed of a gas injection pipe, the experiment section and a measuring instrument. After a lead bismuth alloy is melted in the storing tank, argon is used for pressing the lead bismuth alloy into the experiment loop, and the lead bismuth alloy in the loop subsequently passes through the checking cylinder, a descending section, the electromagnetic flow meter, a horizontal section, the experiment section and a gas-liquid separation section to form closed circulation. The invention further provides the experiment method of the system. The system can bear working conditions with a high temperature and ensure that the lead bismuth alloy cyclically run with a stable state in a large-flow state, and meanwhile system parameters can be simply, conveniently and rapidly adjusted.