40results about How to "Reduce free calcium oxide content" patented technology

The invention relates to a method for producing baking-free slag bricks by using steel slag sludge of a rotating furnace. The bricks are produced by taking tailings and tailing sludge of the rotating furnace as raw materials, taking slag silicate cement as an auxiliary material, adding a small amount of water into the raw materials and the auxiliary material, stirring the raw materials and the auxiliary material to uniformly mix the raw materials and the auxiliary material, pressing the mixture on a brick press, and naturally curing the pressed mixture. The bricks comprise the following compoennts in part by weight: 20 to 50 parts of tailings of the rotating furnace, 50 to 80 parts of tailing sludge of the rotating furnace and 0 to 5 parts of slag silicate cement. The adding amount of the added water is 0 to 5 percent of the total weight of the raw materials. The baking-free bricks are produced by taking the tailings and the tailing sludge of the rotating furnace as main raw materials, adding a small amount of slag silicate cement and water into the main raw materials, and pressing the mixture. The raw materials do not need to be treated and can be directly used and the mouled product is naturally cured, so that the energy is saved; and no any equipment is added, so that the problem that the tailings of the rotating furnace and the tailing sludge of the rotating furnace occupy space and pollute environment is solved by producing the baking-free slag bricks.

The invention relates to a process method for preparing similar cement clinkers by treating steel slag at a thermal state in a way of heat preservation, which belongs to the application technology of the treatment of steel slag in metallurgical industries. The process method for treating the steel slag preparing class cement clinkers at the thermal state in the way of heat preservation comprises the following steps: (1) mixing a rectifying agent of silicon and aluminum and high-temperature converter steel slag generated in the steel-making process; (2) carrying out heat-preservation treatmenton the mixture of the rectifying agent of the silicon and the aluminum and the converter steel slag in the step (1); and (3) cooling to normal temperature quickly so as to obtain similar cement clinkers. In order to conveniently mix the rectifying agent of the silicon and the aluminum and the converter steel slag, the high-temperature converter steel slag can be poured into slag ladles, the rectifying agent of the silicon and the aluminum is added in a dispersing way in the pouring process, and the quality of the steel slag poured into each slag ladle and the variety and the quality of the added rectifying agent can be concretely regulated according to different slag ladles and process conditions. In order to better mix the rectifying agent and the converter steel slag for reacting, nitrogen gas can be blown into the bottoms of the slag ladles for stirring and homogenizing in the heat-preservation process. According to the method, the problem of low stability and activity of the steelslag can be simultaneously solved; and moreover, the process is simple, and the cost is low.

The invention relates to a method for processing convertor steelmaking slag. A raw material containing SiO2 is added into thermal convertor steelmaking slag, so that CaO in the convertor steelmaking slag generates 2CaO.SiO2 through a solid-phase reaction in a high temperature. The 2CaO.SiO2 generating crystal transformation and volume expansion in a cooling process of the convertor steelmaking slag is utilized to realize the natural pulverization of the convertor steelmaking slag, convertor slag with even grain sizes is obtained, and grained iron is magnetically separated. According to the technical scheme, the raw material containing the SiO2 is added into the convertor steelmaking slag in the high temperature, the crystal transformation and the volume expansion of the 2CaO.SiO2 in the cooling process of the convertor steelmaking slag are utilized to realize the natural pulverization of the convertor steelmaking slag, the convertor slag with even grain sizes is obtained, the grained iron is magnetically separated, tailings are recovered, and large amounts of heat energy of high-temperature convertor steelmaking slag in the cooling process are recovered.

The invention relates to a method for preparing Portland cement clinker. The method comprises the following steps: proportionally mixing tetraethoxysilane, a calcium nitrate hydrate, an aluminium nitrate hydrate, a ferric nitrate hydrate, ethanol, nitric acid, hexamethylenetetramine, acetylacetone, deionized water and the like uniformly to obtain four kinds of mixed liquid, fully stirring the four kinds of mixed liquid respectively at the temperature of 50-70 DEG C until proper viscosity to obtain monomineral sols of the Portland cement clinker, then mixing the four monomineral sols in a massratio of (36-55):(24-40):(11-19):(20-31), ageing the mixture to form gel, carrying out heat treatment on the gel at the temperature of 1150-1200 DEG C for 4-6 hours and cooling the gel to the room temperature, thus obtaining the Portland cement clinker. Compared with the prior art, the method has the following advantages: the preparation process is simple; the reaction process is easy to control;and the product has high uniformity and purity and can be fired at the temperature lower than the temperature in the traditional methods.

The invention discloses a road steel slag pretreatment method. Waste steel slag generated in a steelmaking process in a steel mill is intensively stacked after being treated through processes such ascrushing and iron separation, and a solution obtained by mixing a plurality of materials at a normal temperature is used for carrying out continuous spraying treatment on the intensively stacked steelslag. The solution comprises materials including, by weight part, 100 parts of water, 6-10 parts of industrial acetic acid, 0.5-2 parts of monocalcium phosphate, 10-30 parts of calcium chloride and 3-6 parts of sodium pyrophosphate, after the materials are mixed to be uniform, 30-90 days of spraying treatment is carried out on the stacked steel slag at the normal temperature, and the content of free calcium oxide in the steel slag can be obviously reduced. The content of the free calcium oxide of the treated steel slag is lower than 3%, and the steel slag can be used for building and maintaining of high-grade roads.

The invention relates to the technical field of steel slag pulverization, in particular to a steel slag pulverization and carbon fixation treatment system and application thereof. The steel slag pulverization and carbon fixation treatment system uses high-pressure gas as a cold source and power for molten steel slag pulverization, and realizes the low energy consumption and deep pulverization of steel slag. The particle diameter of the obtained steel slag is less than 2mm. Steel slag powder reacts with carbon dioxide and superheated steam in a fluidized reactor to form stable calcium carbonate. Excess steam and carbon dioxide gas can be recycled as industrial waste heat; the steam becomes water to be separated from the carbon dioxide; and the carbon dioxide is used as make-up gas. The steel slag pulverization and carbon fixation treatment system can realize the rapid cooling, pulverization, and carbon fixation of the molten steel slag, and can fix greenhouse gases while saving energy.

The invention relates to a molten steel slag rolling modification treatment device and method. The device comprises a screw feeding device, a rotary feed valve, a pulse feeding device and a material bin. The molten steel slag rolling modification treatment device is located on a thermal state steel slag rolling breaking trolley. The molten steel slag rolling modification treatment device and the rolling breaking trolley move jointly to scatter modifying materials to a slag bed. The treatment method is simple and convenient to operate, and high-temperature thermodynamic conditions of molten steel slag and dynamic conditions that a steel slag rolling breaker walks in a reciprocating manner to stir the steel slag are fully utilized.

The invention relates to the field of building materials, in particular to a reduction tempering agent and application thereof in treating steel slag. The reduction conditioning agent comprises 35 to 90 weight percent of a carbon-containing component; in the carbon-containing component, fixed carbon is greater than or equal to 40.0 wt%, volatile components are less than or equal to 50.0 wt%, and ash content is less than or equal to 10.0 wt%; the reduction tempering agent further comprises fluorite; the mass ratio of the carbon-containing component to the fluorite is (35-90): (2-40). According to the reduction tempering agent provided by the invention, the steel slag can be subjected to a chemical reaction at a relatively low temperature, a valuable metal iron resource is reduced and recovered, and the tempered steel slag with high gelling activity and no stability problem can be obtained and used as a building material resource, so that the whole full-quantization waste-free utilization of the steel slag can be realized, and the production cost is reduced. The large-scale comprehensive utilization of the steel slag is favorably improved.

The invention discloses a method for recovering phosphorus from the urban mud anaerobic digestion solution, comprising: mixing and stirring the fly ash and water with the mass ratio of 1:5-40, standby, producing the leaching liquid; anaerobic digestion of the urban mud, taking the supernatant for acidification to regulate the pH value of the solution for preprocessing; mixing the leaching liquid and the preprocessed digestion liquid according to initial reaction calcium phosphorus molar ratio of 0.5-3.3:1; regulating the reaction pH value to 7.5-11.0, stirring and reacting for 5-120 min; obtaining the calcium phosphate precipitates. The invention subtly utilizes the fly ash leaching solution to provide calcium source and recovers phosphorus in the mode of calcium phosphate, can recover thevaluable products from the mud and the fly ash and relieve the phosphorus load in the subsequent sewage treatment. Because the leaching solution is enriched with hydroxyl ions, the alkali feed quantity is reduced and the recovered products has high purity.

The invention relates to a method for carrying out remelting, reduction and modification treatment on massive steel slag. The method comprises the following steps of (1) mixing materials, uniformly mixing the massive steel slag and a reduced and modified material, and placing into a heating device; (2) increasing the temperature of a mixed material obtained from the step (1) to 1350-1550 DEG C, and stirring at the same time; (3) after the material is completely reacted, naturally separating molten iron from molten slag, discharging the molten iron, and then carrying out cooling treatment on the molten slag. The method disclosed by the invention has the advantages of no steel slag granularity and component limit, short flow, high-efficiency metal element recovery and environmental friendliness; according to the method, the tailings are used as hydraulic cementing materials.

The invention relates to a method for preparing calcium ferroaluminates. The method comprises the following steps: proportionally mixing an aluminium nitrate hydrate, a calcium nitrate hydrate, a ferric nitrate hydrate, hexamethylenetetramine, acetylacetone, deionized water and the like uniformly by a sol-gel method, then stirring the mixture at the temperature of 50-70 DEG C to obtain sol, ageing the sol to form gel, carrying out heat treatment on the gel at the temperature of 750-800 DEG C for 2-4 hours and slowly cooling the gel to the room temperature, thus obtaining the calcium ferroaluminates. Compared with the prior art, the method has the following advantages: the preparation process is simple; the reaction process is easy to control; and the product has high uniformity and purity and can be fired at the temperature lower than the temperature in the traditional methods.

The invention relates to a method for producing baking-free slag bricks by using steel slag sludge of a rotating furnace. The bricks are produced by taking tailings and tailing sludge of the rotating furnace as raw materials, taking slag silicate cement as an auxiliary material, adding a small amount of water into the raw materials and the auxiliary material, stirring the raw materials and the auxiliary material to uniformly mix the raw materials and the auxiliary material, pressing the mixture on a brick press, and naturally curing the pressed mixture. The bricks comprise the following compoennts in part by weight: 20 to 50 parts of tailings of the rotating furnace, 50 to 80 parts of tailing sludge of the rotating furnace and 0 to 5 parts of slag silicate cement. The adding amount of theadded water is 0 to 5 percent of the total weight of the raw materials. The baking-free bricks are produced by taking the tailings and the tailing sludge of the rotating furnace as main raw materials, adding a small amount of slag silicate cement and water into the main raw materials, and pressing the mixture. The raw materials do not need to be treated and can be directly used and the mouled product is naturally cured, so that the energy is saved; and no any equipment is added, so that the problem that the tailings of the rotating furnace and the tailing sludge of the rotating furnace occupyspace and pollute environment is solved by producing the baking-free slag bricks.

The invention discloses a steel slag heat stewing method capable of reducing the content of free calcium oxide in steel slag. The steel slag heat stewing method comprises the steps that after smelting with a converter is finished, liquid steel slag is poured into a heat stewing tank; in a steel slag pouring process, nitrogen at the pressure range of 0.3-0.7MPa is used to carry out blowing on the steel slag, and large steel slag blocks are broken to be crushed by a mixing method; during steel slag pouring, the steel slag put in the heat stewing tank is subjected to initial water drilling slag wakening with the water drilling quantity of 3-5m<3> / h and the water drilling time of 1-5min / furnace slag, and after the heat stewing tank is loaded with the steel slag to 60-70% of the capacity of the heat stewing tank, the water drilling slag wakening is carried out with the water drilling quantity of 3-5m<3> / h and the water drilling time of 5-20min, so to allow the mean temperature of the steel slag in the heat stewing tank to be 850-1100 degrees; after the slag wakening is finished, a heat stewing tank cover is covered, and heat stewing water drilling is carried out with the water drilling quantity and the water drilling time controlled according to a control table, and after the heat stewing water drilling is finished, the steel slag are taken out of the heat stewing tank. With the adoption of the steel slag heat stewing method, the content of free calcium oxide in the steel slag can be reduced to below 3.0%, and the instability of the steel slag is eliminated, so that the performance indexes of the steel slag can meet the industry standards of cement, building materials and the like, the steel slag can be applied to the fields of steel slag powder production, building material products, project backfill materials, etc., and conditions are created for resource utilization of the steel slag.

The invention provides a converter slag stability modifier and an application method thereof, wherein the modifier is a mixture composed of one or more from the group of iron ore tail slag, an iron ore rock dump and blast furnace slag, characterized in that the ingredients, by weight, are 28%-99% of SiO2, 0.01%-20% of Al2O3, 0.01%-20% of CaO, 0.01%-10% of MgO, and 0.01%-22% of TFe. The application method of the converter slag stability modifier comprises material preparing, material feeding, gas blowing stirring, slag tapping, steel slag graining, etc., making f-CaO <=1.5% and realizing stabilizing treatment for the converter slag.