32results about How to "Low cost of environmental protection" patented technology

The invention relates to a comprehensive recovery method for zinc, nickel and cobalt-containing purification slag. The method comprises the following steps: washing the zinc, nickel and cobalt-containing purification slag with hot water till the content of sulfate radicals or chlorine ions of a lotion is smaller than 1g / L and then leaching the purification slag with sodium hydroxide; obtaining zinc and cobalt-containing alkaline leaching liquor and leached slag primarily containing nickel; putting the alkaline leaching liquor in a magnetic field and performing diaphragm electrolysis by takinga magnetic material as an anode and a stainless steel plate as a cathode to obtain metal zinc powder in a cathode region and the cathode and anode slurry primarily containing Co2O3 and Co3O4 in an anode region and the anode; washing and drying the anode slurry, reducing the same directly with hydrogen to obtain metal cobalt powder or sulfuric acid leached out, precipitating oxalic acid to obtain cobalt oxalate, then reducing the cobalt oxalate with hydrogen to obtain metal cobalt powder, and electrolyzing metal cobalt; returning the alkaline residual electrolyte to leach zinc, nickel and cobalt purification slag; and washing the nickel-containing leach residue and leaching the same with sulfuric acid, and enriching the same and performing electrolysis to obtain metal nickel. The method provided by the invention is short in process flow, high in separating recovery rate of zinc, nickel and cobalt and small in wastewater and waste residue amount.

The invention relates to the technical field of hydrometallurgy, in particular to a method for recycling indium and germanium from chlorination distillation residual liquor containing the indium and the germanium. The method comprises the steps that tartaric acid is added to the distillation residual liquor, so that mixed liquor containing InCl4 or InCl6<3> germanium tartrate acid radical anions (Ge(A)3<2>), A representing the tartaric acid) is obtained; indium extraction and germanium extraction are conducted at the same time through a N235-kerosene system extraction agent; and then, indium reverse extraction is conducted through dilute acid, and germanium reverse extraction is conducted through a sodium hydroxide solution. By means of the method, the indium and germanium separation costis lowered; the extraction agent is high in regeneration capacity; the separation difficulty is lowered; the process is easy to implement; and operation is easy and convenient to conduct.

The invention discloses a method for preparing analytical pure sulfuric acid by using smelting gas, belonging to the field of sulfuric acid preparation. The method comprises the following steps: (1) carrying out deep purification to obtain high-purity flue gas; (2) transforming and absorbing to obtain industrial sulfuric acid; (3) evaporating: evaporating the industrial sulfuric acid until SO3-containing gas is obtained; (4) purifying: purifying the SO3-containing gas, obtained by evaporation, for a second time; (5) absorbing: absorbing the purified SO3-containing gas to obtain refined sulfuric acid; (6) removing SO2, removing the SO2 of the refined sulfuric acid to obtain the analytical pure sulfuric acid. In the preparation process, the SO3-containing gas, obtained by evaporating the prepared industrial sulfuric acid, rather than the flue gas is directly adopted as a source of the sulfuric acid to be prepared, so that the purity of the sulfuric acid is improved. Furthermore, the SO3-containing gas obtained by evaporating the industrial sulfuric acid is also demisted by using a demister, and nitrogen oxides are absorbed by using expanded graphite, so that impurities such as the nitrogen oxides which are produced in the preparation process are further removed, and the prepared sulfuric acid reaches the grade of analytical pure.

The invention provides a balanced drying system, comprising an air supply and exhaust main pipeline, and at least two groups of drying units; the drying units each comprises a unit air supply fan and a drying oven, the drying units each is provided with a unit air inlet and a unit air outlet, the drying oven is provided with a drying oven air inlet and a drying oven air outlet, and all of the groups of the drying units are disposed in pairs at intervals on the air supply and exhaust main pipeline via the unit air inlet and the unit air outlet, the unit air inlet is connected with the drying oven air inlet, and the unit air outlet is connected with the drying oven air outlet. The invention has the advantages of concise and stable system, simple adjustment, low exhaust air volume, low energy consumption and the like.

The invention discloses a comprehensive recovery method for solution containing zinc chloride, and relates to the technical field of hydrometallurgy. According to the invention, ZnCl4<2-> and chloridion are directly extracted under the condition of PH of 3 to 5 by adopting a N235-kerosene extraction agent, then an organic phase loaded with zinc and chlorine is reversely extracted by using 30 to 40% of sodium hydroxide, the obtained alkali reverse-phase extraction liquor is subjected to chlorine salt electrolysis, metal zinc powder is obtained in a cathode region, chlorine gas is obtained in ananode region, and residual electrolysis liquor is regenerative sodium hydroxide, so that comprehensive high-efficiency recovery of zinc, chlorine and sodium hydroxide in the solution containing zincchloride is implemented. According to the invention, the process flow is short; higher separation and recovery of all of chlorine, zinc, indium, gallium, bismuth, antimony, sodium carbonate and sodiumhydroxide are obtained, wherein a recovery rate of zinc in zinc powder reaches 95% or more; the comprehensive recovery method is low in production cost and high in economic value of the product, generates few waste residues and little wastewater, is low in environmental-friendly treatment cost and implements economic benefit maximization.

A method for eliminating the silicon dioxide emulsion of an organic extractant. The organic extractant silicon dioxide emulsion is irradiated with microwaves, stirred and irradiated for a certain period of time, and then left to separate phases to obtain a separated and clarified loaded organic phase and a The water phase of the silica flocculent precipitate is loaded with the organic phase and returned for use; the microwave radiation frequency used is 2-100GHz, the power is 100-500W, and the radiation is irradiated while stirring, and the time is 10-30 min; the phase separation time is allowed to stand For 10-20 min, or after more than 80% of the silica emulsion is eliminated, the organic phase and the water phase are separated, and the emulsion in the remaining organic phase is returned to microwave treatment. The present invention uses microwave radiation energy to penetrate organic phases with high dielectric constants such as kerosene without loss, and is easily and better absorbed by silicon dioxide hydrated emulsions, resulting in instantaneous high-temperature dehydration to treat and eliminate the oxidation of organic extractants. Silicon emulsion is characterized by short time, high efficiency, low cost, and no waste residue and waste water.

The invention discloses a self-denitrification system and process for combustion and self-denitration in the concentration and light oxygen-containing zones of a calciner. The side connection, the tertiary air pipe is connected to the bottom of the calciner cone, forming a horizontally partitioned combustion environment with a central oxygen-rich zone and a peripheral low-oxygen zone on the transverse section of the calciner; the kiln gas flue is a strong reduction zone, and the calciner is a combustion environment. In the ember zone, a vertically graded combustion environment with different oxygen peroxide coefficients is formed in the combined combustion space of the kiln gas flue and the calciner. The horizontal partition combustion environment is realized by making the tertiary air enter vertically upward from the center of the bottom of the calciner, and the flue gas enters the air from the side of the calciner by tangential rotation of the volute; the vertically graded combustion environment is realized by fuel graded feeding. The present invention realizes self-denitrification through zone-organized combustion as a whole, improves self-denitrification efficiency, does not reduce the combustion speed of calciner fuel and completely decomposes raw meal, and has no adverse effect on the cement clinker production process.

The invention discloses a self-denitrification system and process for calcining furnace partitioned organization combustion which can adjust the oxygen concentration in the reduction zone. The side of the furnace is connected, and the tertiary air pipe is connected to the bottom of the calciner cone, forming a horizontally partitioned combustion environment with a central oxygen-rich zone and a peripheral low-oxygen zone on the transverse section of the calciner; the kiln gas flue is a strong reduction zone, and the calciner is a In the embers area, a vertically graded combustion environment with different oxygen peroxide coefficients is formed in the combined combustion space of the kiln gas flue and the calciner; a tertiary air branch pipe is set between the tertiary air duct and the kiln gas flue. The horizontal zoned combustion environment is achieved by the tertiary air entering vertically upward from the bottom center of the calciner, and the flue gas is tangentially rotated into the volute from the side of the calciner to realize the combustion environment; the vertically graded combustion environment is realized by fuel graded feeding. The present invention realizes self-denitrification through zone-organized combustion as a whole, improves self-denitrification efficiency, and improves utilization of space in a strong reduction zone.