31results about How to "High defluorination efficiency" patented technology

The invention provides a roasting defluorination device and technology. The roasting defluorination device comprises a feeding system, a mineral powder preheating system, a fluidized-bed roasting system and a vapor preheating system. The fluidized-bed roasting system comprises a fluidized-bed roasting furnace. The feeding system is connected with the mineral powder preheating system. The mineral powder preheating system and the vapor preheating system are connected with the fluidized-bed roasting system. Optionally, the device further comprises a gas absorption system, a cooling system and an air guiding system, the gas absorbing system and the cooling system are connected with the fluidized-bed roasting system, and the air guiding system and the gas absorbing system are connected. The defluorination rate of the roasting defluorination device reaches more than 85%. A solid fluorine fixing agent is used for absorbing fluorine containing tail gas to recycle fluorine resources. Water of a vapor boiler is preheated by heat generated in the high-temperature defluorination tail gas and defluorination material cooling process to generate high-temperature vapor, the heat utilization rate is high, and vapor consumption is low. The roasting process is good in economical efficiency, and the roasting defluorination device and technology are suitable for large-scale continuous industrial production.

Disclosed is a method for removing and recycling hydrogen fluoride from hydrogen chloride gas. The method comprises drying the hydrogen chloride gas containing hydrogen fluoride, and then through calcium / magnesium / aluminum oxide / chloride / hydroxide / carbonate as absorbent, absorbing the hydrogen fluoride contained in the hydrogen chloride gas to obtained defluorinated hydrogen chloride gas and loaded absorbent, wherein the defluorinated hydrogen chloride gas can be directly put into use or absorbed inside water to produce hydrochloric acid for utilization; adding H2SO4 into the loaded absorbent to converted fluorine inside the loaded absorbent into HF, and increasing the temperature to volatize the HF from the reaction system for producing fluorine compounds and further achieving the effect of removing hydrogen fluoride as well as recycling or fluorine resources. The method for removing and recycling the hydrogen fluoride from the hydrogen chloride gas has the advantages of being simple in process and operation, low in production cost, economic, high in efficiency, environmentally-friendly and high in defluorination efficiency, thereby being applicable to industrial application.

The invention belongs to the technical field of water treatment, and specifically relates to a method for photocatalytically degrading perfluorooctanoic acid in water doped with noble metal gallium oxide, comprising the following steps: preparing a noble metal doped gallium oxide catalyst and photocatalytically degrading perfluorooctanoic acid by using noble metal doped gallium oxide. Specifically, the noble metal salt solution is added to the gallium oxide suspension and mixed evenly, and then the reducing salt solution is added dropwise to reduce the metal particles on the gallium oxide surface to prepare a noble metal-doped gallium oxide photocatalyst, and then use the photocatalyst in the Degrade perfluorooctanoic acid under ultraviolet light, so as to achieve the purpose of removing perfluorooctanoic acid in water. The method of the invention has the advantages of simple photocatalyst preparation method, degrading perfluorooctanoic acid under normal temperature and pressure conditions, no need for complex devices and high degradation efficiency.

The invention discloses a method for defluorinating an acidic aqueous solution containing hydrofluoric acid, which comprises the following steps: (a) combining an acidic aqueous solution containing hydrofluoric acid with trialkylchlorosilane or trialkylchlorosilane and hexaalkyldisiloxane The mixture of alkane is reacted, the reaction temperature is 10-80°C, the reaction time is 5-100min, the obtained reaction solution is separated, the upper layer obtains the organic silicon mixture, and the lower layer obtains the acidic aqueous solution after defluorination; (b) the step (a ) the obtained organosilicon mixture is mixed with the alkali solution for regeneration reaction, and the obtained regeneration reaction liquid is separated, the lower layer is obtained with alkali solution containing fluoride salt, and the upper layer is hexaalkyldisiloxane. The invention has the advantages of simple process, high operating flexibility, high defluorination efficiency, and environmental protection.

The invention discloses a non-phosphate precipitation wet phosphoric acid purification method, which belongs to the field of phosphorus chemical industry. The non-phosphate precipitation method wet-process phosphoric acid purification technology is to use the chemical agent to combine with the anion and cation of dilute phosphoric acid to form an insoluble double salt, which is precipitated in the form of non-phosphate, so as to achieve the purpose of wet-process phosphoric acid purification and meet the requirements of high-concentration production. Requirements for phosphate fertilizers, water-soluble fertilizers and industrial-grade phosphate products. The method is stable in removing iron, magnesium, aluminum, arsenic, lead, sodium, potassium, and sulfate radicals in wet-process phosphoric acid, and has simple reaction conditions, short process flow, wide range of reagent sources, low treatment cost, and P 2 o 5 With the characteristics of high recovery rate, it realizes the one-step dilute acid "removal of half and half + weight removal + desulfurization". After treatment, the removal rates of wet-process iron phosphate, magnesium, and aluminum are over 97%, 70%, and 15% respectively. The arsenic and lead in dilute acid are less than 5ppm, and sodium (calculated as NaO) and potassium (calculated as K 2 O meter) respectively less than 0.025%, 0.083%, sulfate less than 0.16%, P 2 o 5 The recovery rate is higher than 98.5%.

The invention discloses a method for catalytically improving wet-process phosphoric acid steam stripping defluorination efficiency, and relates to the technical field of wet-process phosphoric acid defluorination processes. By carrying out arsenic removal and heavy metal removal purification procedures on raw material phosphoric acid, clear purified concentrated phosphoric acid with low impurity content can be obtained; after a defluorination catalyst is added into the purified concentrated phosphoric acid, the defluorination catalyst and a defluorination agent are mixed and heated, and then steam stripping defluorination is performed, so that the defluorination resistance can be effectively reduced, the defluorination efficiency is improved, the consumption of the defluorination agent, steam and electricity in the defluorination process is reduced, and the defluorination cost is reduced; in the defluorination process, a steam stripping defluorination process is adopted, and an indirect steam heating mode is adopted; the defluorinated phosphoric acid production efficiency is high, the yield is high, the consumption is low, the phosphoric acid quality is good, the impurity content is low, the phosphorus-fluorine ratio (P2O5 / F) can reach 285 or above, and the defluorinated phosphoric acid can be directly used for producing feed-grade calcium phosphate.

The invention discloses a load-type fluorine remover used for removing hydrogen fluoride in hydrogen chloride gas, which is composed of a porous carrier and a fluorine removal active ingredient loaded on the porous carrier, the fluorine removal active ingredient can be existed on inner part and external surface of the tunnel of the porous carrier in a thin layer mode with particles of 0.1nm-5mum, and the mass ratio of the fluorine removal active ingredient to the porous carrier is 0.0005-3: 1. The invention also provides a preparation method of the load-type fluorine remover. The preparation method thereof has the advantage of simple process, and the prepared load-type fluorine remover has the advantages of high utilization rate, good fluorine removal effect and green environmental protection.

The invention discloses a high-temperature stripping defluorination method of wet-process phosphoric acid and a device thereof, and relates to the technical field of wet-process phosphoric acid defluorination. In the method, the raw material phosphoric acid is firstly treated to remove heavy metals, and then the solid impurities in the phosphoric acid are removed by clarification and pressure filtration to obtain clarified concentrated phosphoric acid with low solid content; Heat to 70-90°C, pump phosphoric acid into the defluorination tower for stripping and defluorination, keep the phosphoric acid in the liquid storage tank at the lower part of the defluorination tower in a boiling state, and recover the fluorine-containing gas by washing with water to obtain the phosphorus-fluorine ratio P 2 o 5 Defluorophosphoric acid with low fluorine content and / F above 380. In the boiling state of phosphoric acid, the escape efficiency of fluorine-containing gas in phosphoric acid can be improved, the fluorine content in acid can be effectively reduced, and the defluorination efficiency and the output of defluorinated phosphoric acid can be improved. The defluorinated phosphoric acid produced by the method has good quality and high yield, and can not only be directly used to produce feed-grade calcium phosphate, but also can be applied to fields requiring higher phosphoric acid quality.

The invention discloses a system and a preparation method for preparing feed-grade phosphoric acid from wet-process phosphoric acid, and relates to the technical field of phosphoric acid production. The preparation method is composed of processes such as wet-process phosphoric acid desulfate radical removal, heavy metal removal, graded concentration defluorination, air stripping defluorination, steam defluorination and the like. Using wet-process phosphoric acid as raw material to remove sulfate and heavy metal ions in phosphoric acid under different phosphoric acid concentration conditions, the feed grade is completed by using steps such as fractional concentration defluorination section, multi-stage series gas defluorination section and steam defluorination section. Purify phosphoric acid to obtain high-quality feed-grade phosphoric acid. The method for preparing feed-grade phosphoric acid by wet-process phosphoric acid does not require phosphoric acid filtration or pressure filtration, and no slag phosphoric acid and solid waste are generated during the process, with high phosphorus yield, high defluorination efficiency, good recovery of fluorine resources, and P in the product phosphoric acid. 2 o 5 The / F can reach more than 300, the process continuity is good, the device capacity is large, and it also has the characteristics of low comprehensive energy consumption and excellent investment. The maximum can reach 300,000 tons P 2 o 5 / year.

The invention discloses a process of producing feed-grade calcium dihydrogen phosphate through a phosphoric acid circulation impurity removal method, wherein the method comprises following steps: (a) decomposing acid mine; (b) maintaining the temperature and performing sedimentation to obtain a slurry material; (c) feeding the slurry material to a crystallization trough, cooling the slurry material to 30-60 DEG C and performing solid-liquid separation to obtain a filtrate and a filter residue; (d) adding water to the filter residue for making material slurry of which the specific gravity is 1.30-1.60; (e) maintaining the temperature and performing sedimentation to obtain a material slurry; (f) feeding the material slurry in the step (e) to a dryer with high-temperature gas flow to dry the material slurry, and adding an alkaline substance to a dried product to obtain the feed-grade calcium dihydrogen phosphate product; and (g) mixing a filtrate in the step (c) with phosphoric acid by wet process, and removing impurities to obtain an acid liquid used for decomposing the acid mine in the step (a). The process is good in adaptability of phosphorus ore, can ensure the product in the step (f) and heavy metals to meet a standard completely, can reduce discharge load of phosphogypsum and is good in application prospect.

The invention belongs to the field of degradation of persistent pollutants and discloses a method of photocatalytically degrading perfluoro-compounds. The method includes the steps of: a) preparing a double-model mesoporous SiO2 material BMMs, and with phosphotungstic acid as an active component, preparing a HPW / BMMs catalyst through impregnation; b) adding the HPW / BMMs catalyst to a perfluoro-compound solution, and at normal temperature and under normal pressure, irradiating the solution under an ultraviolet lamp to achieve degradation and defluorination to the perfluoro-compounds. The method is simple and has gentle conditions, increases the defluorination rate on the perfluoro-compounds, and achieves effective degradation of the perfluoro-compounds.

The invention discloses a device for removing hydrogen fluoride from tail gas by virtue of dynamic waves. The device comprises a primary dynamic power absorption tower, wherein the primary dynamic wave absorption tower is connected with a secondary dynamic power absorption tower; a first water pump is arranged between the primary and secondary dynamic wave absorption towers; the primary dynamic power absorption tower is connected with a settling tank through a second water pump; the settling tank is connected with a filter pressing and washing kettle which is connected with a centrifuge and a mother liquor tank respectively; the centrifuge is connected with the mother liquor tank; the mother liquor tank is connected with a neutralizing tank and a circulating absorption liquid tank through a third water pump respectively; the neutralizing tank is connected with the circulating absorption liquid tank which is connected with the secondary dynamic wave absorption tower through a fourth water pump; the neutralizing tank is connected with a de-condensed calcium chloride pipe through a fifth water pump. The invention further discloses an implementation method for the device for removing the hydrogen fluoride from the tail gas by virtue of the dynamic waves. The device has the characteristics of simple structure, low construction cost, low production cost, high defluorination efficiency, low liquid-gas ratio, convenience for overhauling and the like.

The invention relates to a governing method for discharging fluorine-containing gas amorphously in an aluminum electrolysis production process. The method comprises the following steps: (1) arrangingmultiple layers of nozzles which are arranged in a staggered manner at a discharge skylight of an aluminum electrolysis plant and spraying an alkaline sodium metaaluminate solution through the nozzles, wherein the alkaline sodium metaaluminate solution absorbs an absorption liquid containing cryolite after the fluorine-containing is discharged amorphously, and gaseous hydrogen fluoride and alkaline sodium metaaluminate react to generate cryolite; (2) collecting and filtering the absorption liquid containing cryolite, wherein the solid phase is cryolite; and adding sodium metaaluminate into thefiltrate for circular use; and (3) demisting the washed gas and discharging the gas into atmosphere. The method provided by the invention has the advantages of being simple in process, convenient tooperate, small in energy consumption, good in pollutant removal effect and the like.

The invention discloses a forage level calcium phosphate production method, comprising that excess phosphoric acid and rock phosphate are added into a reactor to react mixedly; the calcium dihydrogenphosphate material containing fluorine and phosphoric acid; the material is added into a drier to be dried and defluorinated, and the forage level calcium phosphate is made. The forage level calcium phosphate production method has the advantages of fast defluorination, high efficiency, resource saving, low cost, friendly environment, energy saving and emission reducing, which brings the industrialrevolution of forge phosphate.

The invention provides a defluorination calcination device and technology for minerals containing lithium. The defluorination calcination device comprises a mineral powder preheating system, a vapor preheating system, a fluidized bed calcination system and a vapor circulating system, wherein the fluidized bed calcination system comprises a fluidized bed calcination furnace; the mineral powder preheating system and the vapor preheating system are separately connected with the fluidized bed calcination system; the vapor circulating system comprises a steam boiler and a compressor; an air inlet of the steam boiler is connected with the fluidized bed calcination system; a water outlet and a flue gas outlet of the steam boiler are separately connected with an air inlet of the compressor; the air outlet of the compressor is connected with the vapor preheating system; and optionally, the defluorination calcination device also comprises a feeding system, a gas absorbing system and a cooling system. The defluorination rate of the defluorination calcination device achieves 85% or above, and the calcination process is good in economical efficiency; the circulation of a part of vapor is adopted, so that the vapor consumption is reduced; and besides, the cooling of high-temperature defluorination materials is utilized to preheat circulating vapor to generate high-temperature vapor, and the heat utilization ratio is high.

The invention provides a roasting defluorination device and process. The roasting defluorination device includes a material mixing system, a mixture preheating system, a water vapor preheating system and a fluidized bed roasting system. The fluidized bed roasting system includes a fluidized bed Roasting furnace, the material mixing system is connected with the mixture preheating system, the mixture preheating system and the steam preheating system are connected with the fluidized bed roasting system; optionally, the device also includes a gas absorption system, a cooling system and an induction The wind system, the gas absorption system and the cooling system are connected with the fluidized bed roasting system, and the air induction system is connected with the gas absorption system. The device can achieve in-situ defluorination, with a fluorine fixation rate of over 95%, and a defluorination rate of over 90%. High-temperature water is produced by using high-temperature defluorination tail gas, high-temperature flue gas generated by the combustion chamber, and heat generated by cooling defluorinated materials Steam, high heat utilization rate; low water vapor consumption, good economical roasting process, suitable for large-scale continuous industrial production.