The invention belongs to the field of rock wool processing and specifically relates to rock wool and a method for producing rock wool by the utilization of high-alkali red mud The method for producing rock wool by the utilization of high-alkali red mud comprises the following steps: (1) fully mixing red mud, quicklime, ground silica and fly ash, uniformly stirring and pressing by a ball press machine to obtain red mud balls; and (2) airing the pressed red mud balls and uniformly mixing the pressed red mud balls with blocky dolomite and coke, adding the mixture into a cupola furnace and fusing, carrying out fiber forming by the use of a centrifuge, applying a binder to produce flocculent mineral wool, and carrying out post-treatment to prepare the rock wool product According to the rock wool and the method for producing rock wool by the utilization of high-alkali red mud, refuse reclamation can be realized, the environment is protected, production cost of rock wool can be reduced, and the prepared rock wool has good water resistance

Rock wool and method for producing rock wool by utilization of high-alkali red mud

Method for extracting aluminum oxides from aluminum-containing waste residues

The invention discloses a method for one-pot prepared silver covered copper nanometer powder with the controllable shell thickness. The silver covered copper nanometer powder is of a covered type core shell structure. A core layer is made of copper, a shell is made of silver, and the shell thickness is 2-4 nanometers. The method is characterized by comprising the steps that a reduction solution composed of excessive sodium hydrosulfite and sodium hydroxide is added to a copper source solution containing surfactant gelatin to obtain a nanometer copper powder suspension; then, a silver-ammonia solution is added to a suspension containing the copper powder on the condition of non-separation passivation, so that a small amount of silver ions and the copper powder are subjected to a replacement reaction, and a majority of silver ions and the excessive reducing agent are subjected to a reduction reaction; filtering, washing and vacuum drying treatment are performed to obtain the silver covered copper nanometer powder with the grain diameter being 25-55 nanometers. According to the silver covered copper nanometer powder, a cladding material is uniform and compact, the conductivity is good, and the dispersion, oxidation resistance and thermal stability are good. The surface can be uniformly coated with silver on the condition that separation and passivation are not performed on the copper powder suspension, and the industrially and normally adopted pretreatment procedures such as pickling, sensitization and activation are performed on covered copper powder are omitted.

One-pot prepared silver covered copper nanometer powder with controllable shell thickness and preparation method of silver covered copper nanometer powder

The invention discloses a method for crystal seed precipitation of a sodium aluminate solution, comprising the following steps of: 1), mixing a sodium aluminate solution with Al(OH)3 crystal seeds, starting to stir and precipitate at 60 DEG C to 80 DEG C, wherein the causticity ratio of the sodium aluminate solution is 1.25 to 1.60 and the crystal seed coefficient is 1.0 to 4.0; 2), cooling the precipitation system to 40-50 DEG C; and 3), continuously heating the precipitation system within 5 hours to 20 hours, wherein the heating amplitude is 5 DEG C to 25 DEG C, and the final temperature is not higher than 65 DEG C. By adoption of the method provided in the invention, the crystal seed precipitation process of the sodium aluminate solution is effectively reinforced, and the technical and economical indexes of yield in the precipitation, cycle efficiency of aluminium oxide production, and the like are improved.

Method for crystal seed precipitation of sodium aluminate solution

The invention discloses a preparation method of superfine high-white aluminum hydroxide The method includes adding active crystal seeds prepared from industrial-grade aluminium hydroxide into sodium aluminate solution, preparing superfine high-white aluminum hydroxide by means of seed decomposition, and separating, washing and drying the superfine high-white aluminum hydroxide subjected to seed decomposition to obtain the superfine high-white aluminum hydroxide The number of crystal seeds can be reduced effectively, problems caused in the circulation process of the crystal seeds are solved thoroughly, stability of product quality is ensured, and the superfine high-white aluminum hydroxide has competitive advantage comparing with similar products and is simple in technical process, high in operability, less in equipment investment, low in cost, environment friendly and pollution free; meanwhile, materials in the technical process is recyclable, and clean production is realized accordingly

Preparation method of superfine high-white aluminum hydroxide

The invention discloses a method for producing alumina and white carbon black by utilizing red mud and flyash, which is characterized by taking the flyash and the red mud as the raw materials, fully utilizing the resources of Al2O3, SiO2 and Na2O in the flyash and the red mud, mixing the flyash and the red mud with sodium hydroxide or sodium carbonate according to certain proportion and preparing the alumina and the white carbon black through calcining, acid leaching, concentrating, crystallizing, thermal decomposition, water washing, seed precipitation, roasting, etc. The acid in the process is recycled and the waste residues can be used as the raw materials of the cement and ironmaking. The method realizes changing wastes into valuables and changing harm into valuables and reduces the pollution of the red mud and the flyash to the environment. China is short of alumina resources. The development and utilization of the flyash and the red mud lay the foundation for sustainable development of the aluminum industry in China. The method is a new breakthrough in red mud resource utilization, is simple in the process flow of producing the alumina and the white carbon black, utilizes the wastes and is low in production cost.

Method for producing alumina and white carbon black by utilizing red mud and flyash

The invention discloses a production method of inorganic fiber by using red mud and fly ash, mainly comprising the following steps: using the red mud and the fly ash as the raw materials, mixing the raw materials with the one or more of quick lime and industrial solid slag at certain ratio, adding the water, and drying naturally or stream-curing to form the block materials, mixing the raw materials with the coke at certain ratio in a cupola furnace, performing the high temperature melting to obtain inorganic fiber melt, and enabling the melt to flow into a four-roller centrifuge, throwing the melt at extremely high speed through the high-speed rotation of the four-roller centrifuge to form the inorganic fiber with the diameter of 3 to 7 mu m and the length of 7 to 20 cm, and discharging the iron slag from an iron notch at the side bottom of the cupola furnace to recover the iron. The method of the invention transforms the wastes and the harms into treasures, and reduces environmental pollution of the red mud, the fly ash and the industrial solid slag with high calcium content. The method of the invention makes the full use of the resources such as Al2O3, SiO2, Na2O, CaO and Fe2O3 in the red mud, the fly ash and the industrial solid slag with high calcium content, recycles the waste materials, saves the coke and has low production cost.

Production method of inorganic fiber by using red mud and fly ash

Method for preparing high-whiteness aluminium hydroxide micropowder from Bayer process sodium aluminate solution

A purification method of a high-concentration sodium aluminate solution from a Bayer process comprises heating the high-concentration sodium aluminate solution to 80-120 DEG C, strongly mechanically stirring, adding a purifying agent into the sodium aluminate solution to desilicate and remove iron, organic substances and colored substances in the solution, and filtering to separate silica residue from insoluble substances to obtain the purified and decolorized sodium aluminate solution with absorbance lower than 0.30. The purifying agent is calcium oxide, magnesium oxide and/or calcined dolomite. The inventive method can perform deep desilication, remove iron and remove colored organic substances by one-step method.

Purification method of high-concentration sodium aluminate solution from Bayer process

The invention discloses a method for preparing a metal with the surface coated with nano nickel. The metal is ultrafine tungsten powder or molybdenum powder with the average grain diameter D50 not more than 1.3Mum. The method comprises the following steps of: adding the powder into an Ni2 soluble salt solution while continuous stirring is carried out, adding a high polymer surfactant containing coordination group rich in N and O atoms, and stirring to be uniform; then adding a certain amount of NaOH, KOH, ammonia water or Na2CO3, K2CO3 solution into the uniformly stirred solution to regulate pH value of the system to be higher than 6; heating the solution to 40-95 DEG C, adding at least one of hydrazine hydrate, sodium hydrosulphite or sodium hypophosphite as a reducing agent, reactingfor 0.5-2 hours, and defoaming with ethyl alcohol or deionized water in the reaction process; filtering, washing with the deionized water, then washing with a 1-10% diluted NH4Cl or NH4NO3 solution; beating the obtained powder with 0.2-5.0% fatty acid alcoholic solution, modifying the surface of composite powder, filtering again, and heating and drying the powder under the atmosphere of H2 to obtain the ultrafine tungsten powder and molybdenum powder with the surface uniformly coated with nickel metal in nanometer thickness.

Dongfeng Zhao

Papers

Method for producing alumina and white carbon black by utilizing red mud and flyash

Production method of inorganic fiber by using red mud and fly ash

Method for preparing high-whiteness aluminium hydroxide micropowder from Bayer process sodium aluminate solution

Purification method of high-concentration sodium aluminate solution from Bayer process

Method for preparing metal with surface coated with nano nickel