949results about "Sulfur-trioxide/sulfuric-acid" patented technology

A system involving a two-step gasification of a carbonaceous source to produce bulk hydrogen that avoids the early formation of CO₂ and obviates the traditional water gas shift (WGSR) step, carbochlorination of a metallic ore the production of metals found in the ore that utilizes carbon monoxide as an oxygen sink, rather than the traditional coke, and carbon oxides management that eliminates major impediments to emission-neutral power generation and the reduction of major metals. The gasification uses a rotary kiln reactor and gas-gas cyclonic separation process to separate synthesis gas into purified hydrogen and purified carbon monoxide. Purified bulk carbon monoxide issued in metallurgical reduction, and purified bulk hydrogen as fuel for an emission-neutral hydrogen combined cycle (HCC) turbine power generation station. The carbochlorination is integrated with: a) the concurrent separation and purification of all metal-chlorides (metchlors) and capture of CO₂ for passage to the carbon oxides management system; b) the direct reduction of metchlors to nanoscale metallurgical powders and/or to dendritically-shaped particles, including metchlor reduction for the ultrahigh-performance semiconductor metals of the III-V group; and, c) the reforming of metal-oxides with improved crystalline structure from metchlors. The carbon oxides management collects, stores and directs to points of usage, carbon oxides that arise in various processes of the integrated system, and captures carbon monoxide for process enhancement and economic uses and captures carbon dioxide as a process intermediate and for economic uses.

SO₂ and/or NO_x are removed from gaseous CO₂ at elevated pressure(s) in the presence of molecular oxygen and water and, when SO₂ is to be removed, NO_x, to convert SO₂ to sulfuric acid and/or NO_x to nitric acid. The sulfuric acid and/or nitric acid is/are then removed from the gaseous carbon dioxide to produce SO₂-free, NO_x-lean carbon dioxide gas. The invention has particular application in the removal of SO₂ and/or NO_x from carbon dioxide flue gas produced in an oxyfuel combustion process, for example, in a pulverized coal fired power station.

A process for preparing sulfuric acid from used alkylating sulfuric acid by high-temp cracking includes such steps as heating to 1000-1100 deg.C, cracking, acid washing for cleaning, converting twice by contact method, and absorbing twice to obtain qualified sulfuric acid for reuse. It has high recovering rate.

A Hall-effect sensor, wherein a Hall element is disposed in a magnetic path being formed by a magnet and a flux guide, and the magnet, flux guide, and Hall element are integrally held with a molded frame, and the Hall element is fixed to the magnet (or flux guide) or the molded frame. This Hall-effect sensor can easily position the Hall element with higher sensitivity.

The invention discloses a treatment and recovery process of an acid wastewater in a titanium dioxide production process. The treatment and recovery process mainly comprises the following steps: A, pumping the acid wastewater into a membrane filtration unit, filtering by using a filtering membrane, wherein a membrane intercept object is titanium dioxide particle concentrate, and is fed to the system to be reused, and membrane permeate is a crude sulphuric acid, and enters the next step to be treated; B, pumping the crude sulphuric acid obtained in the step A into a sulphuric acid purification unit, decontaminating and purifying the crude sulphuric acid to obtain pure dilute sulphuric acid, wherein a part of pure dilute sulphuric acid is directly reused, and the other part enters the next step to be treated; C, pumping the dilute sulphuric acid obtained in the step B into a reverse osmosis unit, filtering by a reverse osmosis membrane, wherein the intercept object is concentrated sulfuric acid and is fed to a titanium dioxide production system to be used, the permeate is water and can be directly reused as process water, and 99.9% of titanium dioxide particles, 80-90% of sulfuric acid and 60-80% of water can be recovered after the titanium dioxide acid wastewater is processed by the process disclosed by the invention, so that the production cost of an enterprise can be reduced, and the discharge amount of the wastewater and the sludge waste emission are greatly reduced.

The invention discloses a method for purifying smelting waste acid. The method comprises the following steps: adding a coordination agent into a centralized inflow adjusting pool of waste acid discharged from a sulfuric acid smelting system, stirring uniformly, and filtering the mixture in a filter to further remove insoluble granular impurities; separating dilute acid nearly containing no metal ion and low-acid wastewater through a diffusion dialyzer; adsorbing such residual anion impurities as fluorine and chlorine in the dilute acid through ion exchange resin, concentrating the dilute acid in a multi-effect evaporator and recycling the dilute acid in the sulfuric acid system; further treating the low-acid wastewater to reach the national sewage drainage standard. The method disclosed by the invention can be used for quickly and efficiently separating acid from heavy metal ions in the smelting waste acid, the separated dilute acid can be recycled in a sulfuric acid production procedure after being concentrated, and the method has the advantages of low energy consumption and few residues, and can be used for effectively and comprehensively recycling resources in the waste acid. The wastewater treatment cost is low, and the economic benefit is good. The process is simple, the occupation area of equipment is small and industrialized application is easy to achieve.

The invention provides an improved production process of utilizing gypsum to produce sulfuric acid and cement, which relates to the sulfuric acid and cement industry production technology, and the resource comprehensive utilization and environmental protection governing field of the industrial byproduct gypsum. The improved production process is characterized in that natural gypsum with the CaSO4*2H2O as the main composition or the industrial byproduct gypsum is adopted as the main source material; clay, coke and fly ash clinker are used as supplementary materials; the half-water drying gypsum flow, the single stage powder grinding, raw material mixing melting, suspension preheater kiln decomposing calcination, closing diluted acid washing and purification, two-turning and two-suction processes are adopted; the sulfuric acid and cement products are prepared through six steps of source material homogenizing, drying and dehydration, raw material preparation, clinker burning, kiln gas acid production and cement grinding; the improved production process has the advantages of wide range source material, solving the land occupation and environmental pollution problems of the gypsum waste residue, realizing the circulation utilization of sulfur resource, adopting a plurality of new processes and devices, realizing the large scale production easily, advanced technology, mature process, easy operation in production control, low energy consumption, high benefit, no waste water and waste residues exhaust.

The invention relates to a process for recovering sulfuric acid and sulfate from waste acid generated in the preparation of titanium dioxide by using a sulfuric acid method, belonging to the technical field of waste acid treatment in the industrial production. The invention recovers sulfuric acid and sulfate products from waste acid generated in the production process for preparing the titanium dioxide by using the sulfuric acid method through the sedimentation pretreatment and the simple process including the first segment of flash evaporation-crystallization, concentration and separation, the second segment of vacuum evaporation, concentration and separation and the third segment of vacuum evaporation, concentration and separation. The invention has simple process, convenience of operation, simple equipment, high performance price ratio and high yield, high concentration and less impurities of the product acid, can recycle resources without waste liquid or waste residue emission and can be favorable to environmental protection and energy saving, and emitted exhaust mainly contains air and less vapor, is non-toxic to the environment and can effectively overcome the difficulties of fouling and clogging of the equipment. The invention can be widely applied to the recovery of waste acid in the industrial production and be particularly suitable for recovering the waste acid generated in the preparation of titanium dioxide by using the sulfuric acid method.

A process for concentrating diluted sulfuric acid while removing impurities includes such steps as counter-current contact between hot air and atomized diluted sulfuric acid in drying-concentrating tower for heating, evaporating and concentrating, cooling, and separating the educed or deposited impurities for sulfuric acid. Its advantages are low cost and simple process.

The present invention relates to a process for preparing hydrogen gas, and is aimed at providing a technological process capable of combining sulfur-iodine open-circuit circulation and sulfuric aid industry to simultaneously produce hydrogen gas and sulfuric acid and provide electric power and its equipment. Said method includes the following steps: roasting sulfur-bearing mineral, Bunsen reaction, separating HIx phase and H2SO4 phase solution, using electroosmose process to concentrate and purify HIx phase and utilizing HI membrane catalytic decomposition reactor to make decomposition to obtain I2 and find product H2.

The objective of the invention is to provide a process of using sulphur lead-zinc containing tailings to prepare sulphur iron ore concentrate, using magnet-floating combination process or magnet-gravity-floating combination process to produce sulphur iron ore concentrate containing more than 90% sulphur and iron, using the sulphur iron ore concentrate to produce sulphuric acid, getting 98% sulphuric acid of national standard while getting iron ore concentrate power containing more than 60% iron, and sulphur in the tailings is reduced to less than 2%, recovery rate of sulphur iron in ore concentrate is more than 86%. The invention make comprehensive recovery and use of sulphur iron in the lead-zinc tailings.

An industrial process for reclaiming the waste acid in the production of titanium white powder by sulfuric acid method features that the waste acid is concentrated by fume and then by steam. Its advantages are high efficiency, low cost, and no environmental pollution.

The invention relates to a method for improving the concentration of the SO2 in decomposing the calcium sulfate to acid craft and a chemical manufacturing technique of sulphuric acid and cement clinker, in particular to a manufacturing technique of sulphuric acid and cement clinker made from calcium sulfate. The procedures of the invention are as follows: a, under the function of the strong reduction medium, the calcium sulfate is produced into calcium vulcanization in the reactor; b, the reduction product of a procedure is the compound of the calcium vulcanization and the unreacted calcium sulfate; c, the reduction product is transferred to another reaction directly and under the high temperature, the calcium vulcanization and the calcium sulfate react and make into the SO2 and the clinker. The method has the advantages that: the concentration of the SO2 in gas is increased; the production system of sulfate is more stable and the extensive use of phosphogypsum is possible.

The present invention relates to a method for separation and recycling of pure sulfur dioxide from a gaseous mixture in the IS cycle. More specifically, the present invention relates to a method for separation and recycling of pure sulfur dioxide from a gaseous mixture in the IS cycle using an ionic liquid under a specific condition. When compared with the conventional amine-based absorbent, the use of the ionic liquid enables continuous absorption and stripping of SO₂ even at high temperature, and enables a reversible absorption of SO₂ without loss, decomposition or degradation of a solvent due to good chemical stability, thereby enabling separation and recycling of pure SO₂ from a gaseous mixture in the IS cycle.

Provided is a regeneration method for alkylated waste sulfuric acid. The regeneration method comprises: under redox conditions, waste sulfuric acid and oxidants are contacted, organic matters or tiny carbon particles in the waste sulfuric acid are reacted with the oxidants and converted into CO2, N2 and H2O, after steam stripping removal, regenerated sulfuric acid is obtained. The method can be carried out at a low pressure and at a low temperature, device operation energy consumption is low, investment is saved, operation is simple, and device maintenance cost is low.

The invention belongs to the technical field of flue gas acid making, in particular to an acid making system suitable for high-concentration sulfur dioxide-containing flue gas. The acid making system comprises a main system used for converting sulfur dioxide-containing flue gas of which the sulfur dioxide concentration is lower than the set sulfur dioxide concentration value for making acid, and a pre-conversion and absorption system used for treating the sulfur dioxide-containing flue gas of which the sulfur dioxide concentration is at least equal to the set sulfur dioxide concentration value into sulfur dioxide-containing flue gas of which the sulfur dioxide concentration is lower than the set sulfur dioxide concentration value, and mixing the treated sulfur dioxide-containing flue gas of which the sulfur dioxide concentration is lower than the set sulfur dioxide concentration value with sulfur dioxide-containing flue gas of which the sulfur dioxide concentration is at least equal to the set sulfur dioxide concentration value and which is about to enter the system, so that the sulfur dioxide concentration value of the flue gas which finally enters the main system is lower than the set value. By the acid making system, diluent air quantity supplemented to the main system is small or even diluent air is not needed to be supplemented; and pre-conversion reaction heat is fully utilized to maintain the heat balance of the whole system, and the load of the main system is not increased through pre-absorption, so that a large amount of equipment investment and operating cost are saved.

The invention relates to a method for regenerating and recovering sulfuric acid from waste acid generated in the production of the sulfuric acid or waste acid collected from waste lead-acid storage batteries, comprising the following steps of: firstly preparing purified gas containing H2S with volume percent of 2.5%-5%, CO2 with volume percent of 20%-45% and N2 with volume percent of 50%-77.5; supplying the purified gas to a waste acid solution with the flow rate of 10-20 m3/h and the stirring speed of 300-400 rpm at the speed of 400-600 L/h so that heavy metal impurities in the waste acid solution and S2+ react to generate a sulfide; precipitating, filtering and separating the generated sulfide so that the sulfide is purified and removed from a dilute sulfuric acid solution; and replenishing the filtered dilute sulfuric acid solution which replaces new water into the dry-adsorbing procedure of a flue gas acid making systemso that the sulfuric acid in the waste acid solution is recovered into industrial sulfuric acid. The method has the advantages of low production cost, short flow, high cyclic utilization rate, low energy consumption, treatment of wastes by using wastes, small environmental pollution and high level of automation.

The invention relates to a method for decolorizing sulfuric acid by using hydrogen peroxide. The method includes the following steps of injecting a hydrogen peroxide solution to the sulfuric acid in a closed sulfuric acid decolorizing tank at a speed of 6-18L/min*t with a volume ratio of the sulfuric acid to the hydrogen peroxide solution being 100: (6-22); and simultaneously continuously stirring a mixture at a speed of 8-15 revolutions per minute to obtain the finished sulfuric acid. By means of the hydrogen peroxide solution, the method is strong in oxidizability, good in selectivity, simple in process, convenient, flexible and capable of decolorizing tawny or black brown sulfuric acid; under acidic conditions, reduzate of the hydrogen peroxide is water, other metal ions can not added to the sulfuric acid finished product, and the quality of the sulfuric acid finished product can not be changed; therefore, the problem that the chromaticity and the transparency of the sulfuric acid finished product prepared by gypsum flue gases can't reach the standard can be eliminated, the quality of gypsum flue gas acid can reach the standard of high-class products of industrial concentrated sulfuric acid, the market competitiveness of the gypsum acid is improved, and economic benefits of enterprises are increased.

The invention relates to a process for treating amantadine bromination waste water and mineral acid and alkali recycling through a bipolar membrane electrodialysis process, which comprises the following steps: firstly, filtrating bromination waste water through micropore filtration film; then pumping the bromination waste water into a salt chamber of the bipolar membrane electrodialysis device, pumping tap water into an acid chamber and an alkali chamber of the bipolar membrane electrodialysis device, and pumping Na2SO4 solution into electrode liquid of the two ends of the bipolar membrane electrodialysis device; and finally, starting the bipolar membrane electrodialysis device and recycling the acid and the alkali. According to the invention, a bipolar membrane electrodialysis technology is used for the treatment of degradation-resistant amantadine bromination waste water, and realizes the recycle of the mineral acid and the alkali in waste water. The process has the following advantages: bromine irons in waste water containing bromine can be removed, the desalination rate is higher than 95 percent, the hydrogen ion concentration is decreased from 2.95 mol/L to 0.003 mol/L below, and avoids secondary contamination; the process enables the degradation-resistant pharmaceutical wastewater to become biochemical degradable organic wastewater, and emits qualified waste water after the biochemical treatment; and the control effectiveness is good, the operation is convenient, and the process has a favorable application prospect.

Disclosed is a method which recovers pure acid from the waste acid contains metallic ion and reproduces alkaline, and belongs to the environmental protection field. The process steps include that: (a) the waste acid solution with the acid concentration 10%-40% is processed with the first level diffusion dialysis; (b) the residue after the step a is processed with the second level diffusion dialysis; the volume ratio of the first level (or the second level) waste acid (or the first level diffusion residue) in the first level (or the second level) diffusion dialysis groove residue and the acid recovery chamber collected solution is 1:0.5-1:3.0; the flow rate of the waste acid (or the first level diffusion residue) is enabled to be 0.2-0.6L/h; the flow rate of the acid recovery chamber collected solution is 0.1-1.8L/h; (c) the second residue after the step b is processed with neutralization and deposition; (d) the neutralized filtrate after the solid-liquid separation-filtration is fed to the three compartment electrodialysis groove middle chamber, the electrodialysis is processed for 1-3h under the voltage 5-15V to obtain the reproduction acid and reproduction alkaline. The method which recovers pure acid from the waste acid contains metallic ion and reproduces alkaline has the advantages of high acid recovery rate, low production cost and energy-consumption, less film pollution, saving water, reducing discharge and no secondary pollution.