WO2017173717A1 - 一种磷石膏分解气直接用于湿法磷酸生产的方法 - Google Patents

一种磷石膏分解气直接用于湿法磷酸生产的方法 Download PDF

Info

Publication number
WO2017173717A1
WO2017173717A1 PCT/CN2016/083255 CN2016083255W WO2017173717A1 WO 2017173717 A1 WO2017173717 A1 WO 2017173717A1 CN 2016083255 W CN2016083255 W CN 2016083255W WO 2017173717 A1 WO2017173717 A1 WO 2017173717A1
Authority
WO
WIPO (PCT)
Prior art keywords
phosphoric acid
decomposition
phosphogypsum
production
gas
Prior art date
Application number
PCT/CN2016/083255
Other languages
English (en)
French (fr)
Inventor
龚家竹
Original Assignee
成都千砺金科技创新有限公司
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 成都千砺金科技创新有限公司 filed Critical 成都千砺金科技创新有限公司
Publication of WO2017173717A1 publication Critical patent/WO2017173717A1/zh

Links

Images

Classifications

    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B25/00—Phosphorus; Compounds thereof
    • C01B25/16—Oxyacids of phosphorus; Salts thereof
    • C01B25/18—Phosphoric acid
    • C01B25/22—Preparation by reacting phosphate-containing material with an acid, e.g. wet process
    • C01B25/222—Preparation by reacting phosphate-containing material with an acid, e.g. wet process with sulfuric acid, a mixture of acids mainly consisting of sulfuric acid or a mixture of compounds forming it in situ, e.g. a mixture of sulfur dioxide, water and oxygen
    • C01B25/223—Preparation by reacting phosphate-containing material with an acid, e.g. wet process with sulfuric acid, a mixture of acids mainly consisting of sulfuric acid or a mixture of compounds forming it in situ, e.g. a mixture of sulfur dioxide, water and oxygen only one form of calcium sulfate being formed
    • C01B25/225—Dihydrate process

Definitions

  • the invention relates to the field of resource reuse of phosphogypsum, in particular to a method for directly decomposing gas of phosphogypsum for use in wet process phosphoric acid production.
  • Phosphogypsum is the main solid waste for the production of high-concentration phosphate fertilizer. China's phosphorus chemical production ranks first in the world. In 2015, China's wet-process phosphoric acid production was about 15 million tons (P 2 O 5 %), and by-product phosphogypsum was 80 million tons. At the same time, it needs to consume 40 million tons of sulfuric acid, ranking first in the world.
  • Phosphogypsum is a huge industrial solid by-product that has to be produced under the living conditions of “population and food”, in order to solve the problem of massive accumulation of phosphogypsum.
  • the current treatment method is usually open storage, and the calcium and sulfur resource elements contained in the phosphogypsum are not utilized, that is, occupying the land and bringing environmental hazards.
  • the chemical decomposition of phosphogypsum to produce cement in parallel with sulfuric acid is the best way to solve the recycling of solid waste and sulfur resources in phosphorus chemical industry, namely, saving sulfur resources and utilizing calcium resources.
  • patent number ZL201310437466.3 (patent name: a gypsum production method for joint production of sulfuric acid), patent number ZL201410070462.0 (patent name: energy saving and consumption of gypsum Inventive patent ZL201410069087.8 (patent name: high silica phosphate production of phosphoric acid by-product low silicon phosphogypsum method) and other invention patents have indirectly or directly in the phosphate rock calcium and silicon The elements are processed in circular economy or utilized.
  • the above patent solves the problem of decomposition efficiency and production of phosphogypsum, or the emission of tail gas from sulfuric acid production; however, the chemical energy of the decomposition gas of phosphogypsum is still not fully utilized, and the best circular economy means has not been achieved.
  • the gypsum decomposition gas SO 2 is subjected to dust removal, acid washing or water washing purification, and then subjected to gas phase catalytic oxidation to SO 3 , and sulfuric acid is absorbed by sulfuric acid.
  • sulphur oxide gas is used in traditional sulphuric acid production, whether it is "one turn and one suction" or two-stage multi-stage conversion and two absorption "two-rotation two-suction", because the sulphuric acid plant is decomposed in the phosphogypsum
  • the investment cost in the recycling process is huge, almost 2/3 of the total investment, and the chemical properties of the alkali chemical energy of the phosphate rock and the acidity of the decomposition gas are not scientifically utilized, and the phosphogypsum is also caused.
  • the decomposition of gas cannot be a passive situation of economic resource utilization.
  • phosphogypsum is used as a resource for recycling wet-phosphorus chemical production.
  • the practical problems of sulfur resource recycling and non-phosphorus gypsum discharge have urgently needed to develop sustainable advanced
  • the production technology meets the needs of human survival and production, and achieves the harmonious unity of “Jinshan Yinshan and Green Water Mountain”.
  • the technical solution adopted by the present invention is as follows: a method for directly utilizing a phosphogypsum decomposition gas for wet process phosphoric acid production, comprising the following steps:
  • the phosphate rock is prepared by wet grinding to obtain a phosphate slurry B;
  • the gypsum decomposition gas S which is a phosphogypsum, or a natural gypsum, or a thermal power plant desulfurization gypsum, or a sulfuric acid method titanium white waste acid treatment gypsum, or other Industrial by-product gypsum is produced by reduction and decomposition;
  • decomposition gas S obtained in the step (2) is directly subjected to the gas, liquid and solid three-phase mixed decomposition and absorption chemical reaction using the phosphorus slurry B obtained in the step (1) to obtain the tail gas A and the calcium sulfate-containing phosphoric acid.
  • the phosphogypsum obtained in the step (3) is further subjected to reductive decomposition to produce a decomposition gas S for use in the step (3).
  • the invention decomposes the gypsum decomposition gas S directly with the phosphorous slurry B prepared by the wet process phosphoric acid, and carries out the synergistic reaction of chemical decomposition, precipitation and absorption of gas, solid and liquid three-phase mixing, and after a plurality of countercurrent three-phase mixed reaction, the phosphorus is made.
  • the ore is decomposed into phosphoric acid and calcium sulfite, and the calcium sulfite is oxidized into calcium sulfate in the liquid phase to obtain the wet phosphoric acid slurry C; the gypsum decomposition gas S is all converted into calcium sulfate, and the sulfur dioxide in the exhaust gas A is far lower than the emission.
  • the decomposition gas is no longer processed into sulfuric acid, eliminating the intermediate process of producing sulfuric acid, eliminating the investment in production of sulfuric acid and production, scientifically and rationally utilizing the chemical energy of phosphate rock and gypsum decomposition gas, The innovative effect of the three arrows of the arrow;
  • the first-stage three-phase mixed reaction the gypsum decomposition gas S directly reacts with the calcium dihydrogen phosphate solution obtained by the two-stage three-phase mixed reaction to form a three-phase mixed reaction to form calcium sulfate and phosphoric acid, and the phosphoric acid reacts with the incompletely reacted phosphate rock to form phosphoric acid.
  • the dihydrogen calcium continues to carry out a three-phase mixed reaction with the decomposition gas, and then precipitates calcium sulfate to react the formulas (1) to (4).
  • the exhaust gas of the decomposed gas which is almost removed in the second stage is directly mixed with the phosphate slurry for three-phase mixing reaction, and the carbonate in the phosphate rock reacts with the low concentration SO 2 in the exhaust gas to produce sulfate.
  • the reaction formulas (8)-(11) function as a desulfurization.
  • the decomposition temperature of the phosphogypsum decomposition gas S from the outlet of the suspension preheater of the calcining kiln is 300-400 ° C, preferably 300-350 ° C, and the volume concentration of SO 2 in the gas may be unlimited, 0-14%. .
  • the circulating solid slurry ratio of the first-stage three-phase mixed reactor is 1.5-5, the reaction temperature is 75-100 ° C, the P 2 O 5 concentration of phosphoric acid is 20-40%, and the exhaust gas A1 temperature is 100-125 ° C;
  • the circulating slurry of the two-stage three-phase mixing reactor has a solid-liquid ratio of 4-50, preferably 8-12, a reaction temperature of 60-100 ° C, and an exhaust gas A2 temperature of 62-100 ° C; a three-stage three-phase mixed reaction cycle
  • the slurry solid-solid ratio is 5-60, preferably 20-25, the reaction temperature is 50-85 ° C, the exhaust gas A3 temperature is 52-95 ° C, and the SO 2 volume concentration in the gas phase is as low as 100 PPM or less.
  • the tail gas A3 from the three-stage three-phase mixed reactor is sent to the wet-process phosphor tail gas treatment process for washing and cooling, and the F is recovered.
  • the gas, liquid and solid three-phase mixed decomposition and chemical reaction absorption device is a single-stage or multi-stage series device, or an integrated device assembled by a multi-stage mixed decomposition reaction device;
  • the liquid of the slurry: the solid ratio is in the range of 1:1-5, preferably 1:2-3, the temperature is normal temperature, the fineness is over 80-200 mesh; the pseudogypsum decomposition gas enters the SO 2 original of the three-phase mixed reactor
  • the concentration is not limited.
  • the gas, liquid and solid three-phase mixed decomposition and chemical reaction absorption device is a multi-stage series device.
  • the excess heat generated by the mixed decomposition and absorption chemical reaction described in the step (3) is removed by the heat exchanger and recovered.
  • the calcium sulfite produced by the decomposition reaction is mixed, and air is added to the reaction production device to be oxidized to calcium sulfate.
  • the wet-process phosphoric acid device produces and separates the wet phosphoric acid and phosphorus. plaster.
  • the invention has the advantages that since the gypsum decomposition gas is directly used for the production of wet process phosphoric acid, the decomposition gas is no longer processed into sulfuric acid, the intermediate process for producing sulfuric acid is eliminated, and the device and production for producing sulfuric acid are omitted.
  • the three-phase mixing reaction does not require a concentration range of SO 2 in the phosphogypsum decomposition gas
  • the operating conditions of the gas production of the reduction and decomposition of the phosphogypsum are relaxed.
  • the method also opens up a new way for the recycling of ultra-low concentration SO 2 , which saves energy, reduces production cost, improves production efficiency, reduces investment, and increases production.
  • FIG 1 Schematic diagram of the process of the present invention
  • Ball mill 2. Phosphate slurry storage tank; 3. Phosphate slurry pump; 4. First-stage three-phase mixed reactor; 5. First-stage circulation pump; 6. Two-stage three-phase mixed reaction absorber; Stage circulating pump; 8, three-stage three-phase mixing reactor; 9, three-stage circulating pump; 10, phosphoric acid slurry storage tank; 11, phosphoric acid slurry pump; 12, heat exchange device I; 13, heat exchange device II; 14. Heat exchange device III; 15, cyclone dust collector; 16-19 suspension preheater.
  • phosphate rock 36219.6 kg of phosphate rock and water are added to the mill 1 to prepare a phosphate slurry B, the moisture content of which is 70% by mass, and the phosphate slurry B is placed in the phosphate slurry storage tank 2 for use.
  • the composition of phosphate rock is shown in Table 1-1:
  • Table 1-1 Phosphate composition table (% by mass)
  • the phosphogypsum decomposition gas S is discharged from the decomposition calcining kiln. After the heat exchange of the suspension preheater 16-19, the gas temperature is lowered to 320 ° C, and the decomposition gas is 2530.52 Kmol gas per hour.
  • the composition is shown in Table 1-2.
  • the gas enters the temperature after cooling by the heat exchanger device I12 and reaches a temperature of 85 ° C.
  • the replaced heat is sent to the heat energy recovery, and then the decomposition gas S enters the cycle of the first-stage three-phase mixing reactor 4 and the first-stage circulation pump 5
  • the reaction slurry is subjected to a solid-liquid, gas-gas three-phase mixed chemical reaction, which decomposes SO 2 in the gas S and calcium ions in the liquid to form CaSO 3 , and then oxidizes to CaSO 4 under the action of air, and the first-stage three-phase mixed reactor 4
  • the circulating slurry temperature is 95 ° C, the P 2 O 5 concentration is 38%, the liquid-solid ratio is 3, and the air is blown into the first-stage three-phase mixing reactor 4 by 1230.30 Kmol per hour; from the first-stage three-phase mixed reactor 4 175302.86 kg of phosphorus slurry C1 is discharged per hour to the phosphoric acid slurry storage tank 10,
  • the gas temperature of the exhaust gas A1 discharged from the first-stage three-phase mixed reaction device is 85 ° C, and the gas composition is shown in Table 1-3:
  • the gas from the first-stage three-phase mixing reactor is 4541.09Kmol into the two-stage three-phase mixing reactor 6, and the SO 2 in the gas continues to react with the circulating slurry fed from the secondary circulation pump 7 to form CaSO 3 , the second stage.
  • the temperature of the three-phase mixed reactor 6 is 95 ° C, and the excess heat of the slurry after the reaction is removed by the heat exchange device 13 and the heat is recovered, and the 175,647.63 kg of the phosphorus slurry from the second-phase three-phase mixed reactor 6 overflows to the first The first-stage three-phase mixed reactor 4, while the 177647.48 kg slurry overflows from the three-stage three-phase mixed reactor 8 to the two-stage three-phase mixed reactor 6, and the exhaust gas A2 temperature from the two-stage three-phase mixed reactor 6 is 85. °C, the gas composition is shown in Table 1-4.
  • the gas A24713.04Kmol from the two-stage three-phase mixing reactor enters the three-stage three-phase mixed reactor 8, and reacts with the circulating slurry fed from the three-stage circulating pump 9, and the SO 2 in the gas A2 generates CaSO 3 , and the reaction Excess heat in the slurry is removed and recovered by the heat exchange device III.
  • the temperature of the three-stage three-phase mixed reactor 8 is 95 ° C, and the 177647.48 kg of the slurry is discharged to the secondary three-phase mixed reactor 6.
  • the 127,348.74 kg of pale acid from the wet-process phosphophosphorus gypsum separation unit was added to the three-stage three-phase mixed reactor 8, the amount of phosphate slurry added was 51,742 kg, and the gas tail gas A3 from the three-stage three-phase mixed reactor was at 85 °C.
  • the gas composition is shown in Table 1-5; the wet-process phosphoric acid tail gas system treats the fluoride therein.
  • Phosphorus ore 21357.24 kg and water were added to the mill 1 to prepare a phosphate slurry with a water content of 70%.
  • the phosphate slurry was placed in the phosphate slurry tank 2 for use.
  • the composition of the phosphate rock is shown in Table 2 1.
  • the phosphogypsum decomposes the decomposition gas S from the calcining kiln, and after the heat exchange of the suspension preheater 16-19, the gas temperature drops to 330 °C.
  • the gas produced 2106.7 Kmol per hour, the composition of which is shown in Table 2-2.
  • the decomposition gas S passes through the 12 heat exchange device I and then the temperature reaches 86 ° C, and the heat is recovered, and then the decomposition gas S enters the first-stage three-phase mixing reactor 4 and the circulating reaction slurry fed by the primary circulation pump 5 to solidify.
  • liquid, gas three-phase mixed chemical reaction decomposition of SO 2 in the gas S and calcium ions in the liquid to form CaSO 3 and simultaneously bubbling air 1003.17Kmol in the three-phase mixing reactor 4, thereby oxidizing CaSO 3 to CaSO 4 ,
  • the circulating slurry temperature of the three-phase mixed reactor 4 is 96 ° C, the P 2 O 5 concentration is 40%, the liquid-solid ratio is 3; and the 83,720.38 kg phosphorus slurry C1 overflow from the first-stage three-phase mixing reactor 4
  • the wet-process phosphoric acid unit is adjusted, and the slurry is sent to separate the solid phase calcium sulfate, thereby obtaining a finished phosphoric acid of 16961.92 kg, and the P 2 O 5 concentration thereof is 40%.
  • the temperature of the exhaust gas A1 from the first-stage three-phase mixed reactor is 86 ° C, and the composition is shown in Table 2-3;
  • the gas A13964.54 Kmol discharged from the first-stage three-phase mixing reactor 4 enters the two-stage three-phase mixing reactor 6, and the SO 2 in the gas continues to react with the circulating slurry fed from the secondary circulation pump 7 to generate CaSO 3 .
  • the temperature of the two-stage three-phase mixed reactor 6 is 96 ° C. After the reaction, the excess heat of the slurry is removed by the heat exchange device 13 and the heat is recovered, and the overflow of the phosphorus slurry from the secondary three-phase mixed reactor 6 is 105563.87 kg.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Inorganic Chemistry (AREA)
  • Treating Waste Gases (AREA)
  • Compounds Of Alkaline-Earth Elements, Aluminum Or Rare-Earth Metals (AREA)

Abstract

提供一种磷石膏分解气直接用于湿法磷酸的生产方法。其步骤为：将磷矿经过湿法研磨制备得到磷矿浆，与磷石膏分解产生的SO2分解气直接进行气液固非均相化学反应，得到亚硫酸钙固体和磷酸溶液，液相中亚硫酸钙被氧化为硫酸钙固体和磷酸的混合溶液，送湿法磷酸生产装置生产湿法磷酸。该方法省去了传统的硫酸生产过程，简化了装置，缩短了工艺，做到了湿法磷酸生产硫资源的全循环利用。

Description

一种磷石膏分解气直接用于湿法磷酸生产的方法 技术领域
本发明涉及磷石膏的资源再利用领域，尤其涉及一种磷石膏分解气直接用于湿法磷酸生产的方法。
背景技术
磷石膏是高浓度磷肥生产的主要固体废物，我国磷化工产量已居世界第一位，2015年我国湿法磷酸生产约1500万吨(P2O5％)，副产磷石膏8000万吨，同时需要消耗硫酸产量4000万吨，位居世界第一位。
磷石膏是关系到“人口、粮食”生存条件下不得不产生的庞大的工业固体副产物，为了解决磷石膏大量堆积的问题。目前的处理方法通常是采用露天堆存，磷石膏中所含的钙与硫资源元素没有予以利用，即占有土地，又带来环境危害。磷石膏化学分解生产水泥并联产硫酸，是解决磷化工固废堆存与硫资源循环利用的最佳途径，即节约硫资源，又利用了钙资源。但是，作为磷石膏分解气用于硫酸的生产,其硫酸装置投资大，且要经过气体除尘、净化、催化转化、酸吸收等一系列的冗长流程与繁琐的操作方法方可生产硫酸，不利于磷石膏的最佳循环经济效益。
发明人在专利号ZL94111776.6(专利名称：一种硫酸法生产磷 酸及含磷溶液的方法)，成功应用了磷矿中碳酸盐和磷酸钙能与湿法磷酸中的硫酸和磷酸发生反应的原理，解决了湿法磷酸生产饲料磷酸盐的硫酸与石灰消耗高的问题，大幅度减低了硫酸与石灰原料的用量，并奠定了今天具有国内独创的饲料磷酸盐生产技术。其后在专利号ZL97107676.6，(专利名称：利用湿法磷酸盐废渣生产磷酸铵肥料的方法)，经济的解决了饲料磷酸盐脱氟渣作为肥料磷酸铵及复混肥基础磷源肥料的生产难题，使饲料磷酸盐生产企业获得了巨大的经济与社会效益。作为磷矿资源全利用的生产开发，发明人又在专利号ZL201310437466.3(专利名称：一种石膏生产水泥联产硫酸的生产方法)、专利号ZL201410070462.0(专利名称：节能降耗的石膏生产水泥联产硫酸的方法)和专利号ZL201410069087.8(专利名称：高硅磷矿生产磷酸副产低硅磷石膏的方法)等发明专利中已间接或直接的将磷矿中钙元素和硅元素进行循环经济加工或资源化利用。
中国专利申请(CN10467728)“一种脱出硫酸尾气中二氧化硫的方法”，采用20-60％磷矿浆将“两转两吸”硫酸生产尾气中二氧化硫由800mg/m3降到100mg/m3以下，吸收二氧化硫的磷矿浆用于磷矿反浮选脱镁工序的原料。该方法正如现有热电厂采用石灰脱出烟气中的二氧化硫一样，仅是将磷矿浆代替石灰浆对低含量二氧化硫气体进行吸收，且吸收二氧化硫的量相对较少，且仅用于磷矿选矿原料；未能的解决湿法磷酸生产硫资源的循环与硫酸装置昂贵的投资与生产费用问题。
上述专利尽管解决了磷石膏的分解效率与生产问题，或硫酸生产 尾气的排放问题；但是，磷石膏分解气的化学能量仍然没有得到充分地利用，且还未达到最佳的循环经济手段。现有的硫酸生产技术，将石膏分解气SO2经过除尘、酸洗或水洗净化，再进行气相催化氧化成SO3，用硫酸吸收得到硫酸。作为磷石膏分解气的氧化硫气体用于传统的硫酸生产，无论采用“一转一吸”还是采用两次多段转化和两次吸收的“两转两吸“，因硫酸装置在磷石膏分解气循环利用的生产过程中所占的投资费用巨大，几乎要达到总投资的2/3，且磷矿的碱位化学能与分解气的酸位化学能没有得到科学的利用，也造成了磷石膏分解气不能经济资源利用的被动处境。
随着环保要求的日益提高和磷化工可持续发展生成技术要求，磷石膏作为资源循环利用的湿法磷化工生产，硫资源的循环与无磷石膏排放的现实问题已迫切需要开发可持续的先进生产技术，满足人类生存和生产需要，做到“金山银山与绿水青山”的和谐统一。
发明内容
本发明的目的就在于提供一种磷石膏分解气直接用于湿法磷酸生产的方法，以解决现有技术还不能最经济的利用磷石膏的问题。
为了实现上述目的，本发明采用的技术方案是这样的：一种磷石膏分解气直接用于湿法磷酸生产的方法，包括以下步骤：
(1)、将磷矿经过湿法研磨制备得到磷矿浆B；
(2)、制备石膏分解气S，所述石膏分解气S，为将磷石膏，或天然石膏，或热电厂脱硫石膏，或硫酸法钛白废酸处理石膏，或其它 工业副产石膏进行还原分解而产生；
(3)、将步骤(2)所得的分解气S用步骤(1)所得的磷矿浆B直接进行气、液、固三相混合分解和吸收化学反应，得到尾气A和含硫酸钙的磷酸料浆C；
(4)将步骤(3)所得的磷石膏再进行还原分解生产分解气S，用于步骤(3)
本发明将石膏分解气S，直接与湿法磷酸制备的磷矿浆B进行气、固、液三相混合的化学分解、沉淀与吸收的协同反应，经过多次逆流三相混合反应，使磷矿分解成磷酸和亚硫酸钙，亚硫酸钙在液相被空气氧化成硫酸钙，获得湿法磷酸料浆C；石膏分解气S全部转化成硫酸钙，排出尾气A中的二氧化硫远低于排放标准；分解气不再加工成硫酸，省去了生产硫酸的中间过程，省去了生产硫酸的装置与生产投资，科学合理利用了磷矿与石膏分解气所具有的化学能量，起到“一箭三雕”的创新效果；
其中，磷矿浆B与石膏分解气S的三相混合反应原理为：
(一)磷石膏分解气直接与逆流送来的混合反应料浆进行三相混合分解反应，并氧化新生态的亚硫酸钙：
SO2+Ca(H2PO4)2+3H2O＝CaSO3·2H2O↓+2H3PO4          (1)
SO3+Ca(H2FPO4)2+3H2O＝CaSO4·2H2O↓+2H3PO4         (2)
Ca5F(PO4)3+7H3PO4＝5Ca(H2PO4)2+HF                   (3)
2CaSO3·2H2O+O2＝2CaSO4·2H2O↓                     (4)
(二)上述(一)反应后的尾气与(三)逆流送来的混合反应料浆进 行三相混合反应，并氧化新生态的亚硫酸钙：
6SO2+2Ca5F(PO4)3+18H2O＝6CaSO3·2H2O↓+3Ca(H2PO4)2+CaF2↓    (5)
6SO3+2Ca5F(PO4)3+18H2O＝6CaSO4·2H2O↓+3Ca(H2PO4)2+CaF2↓    (6)
2CaSO3·2H2O+O2＝2CaSO4·2H2O↓                              (7)
(三)上述(二)反应后的尾气直接与磷矿浆进行三相混合反应，磷矿中碳酸盐将尾气的低浓度SO2全部吸收沉淀
SO2+CaCO3+2H2O＝CaSO3·2H2O↓+CO2↑                (8)
SO2+MgCO3+2H2O＝MgSO3·2H2O+CO2↑                  (9)
SO3+CaCO3+2H2O＝CaSO4·2H2O↓+CO2↑                (10)
SO3+MgCO3+2H2O＝MgSO4·2H2O+CO2↑                  (11)
即：
一级三相混合反应：石膏分解气S直接与二级三相混合反应得到的磷酸二氢钙溶液进行三相混合反应，生成硫酸钙和磷酸，磷酸再与未完全反应的磷矿反应生成磷酸二氢钙，继续与分解气进行三相混合反应，再沉淀出硫酸钙，反应式(1)-(4)。
二级三相混合反应，在一级反应已被磷酸二氢钙反应吸收沉淀掉的大部分分解气的尾气与磷矿中氟磷灰石进行三相混合反应，生成硫酸钙和磷酸二氢钙溶液，反应式(5)-(7)。
三级三相混合反应，在第二级几乎被除去完的分解气的尾气直接与磷矿浆进行三相混合反应，磷矿中的碳酸盐与尾气中低浓度SO2反应，生产硫酸盐反应式(8)-(11)，起到脱硫的作用。
本发明中磷石膏分解气S从煅烧窑的悬浮预热器出口出来的温 度为300-400℃，最好是300-350℃，气体中SO2体积浓度可以不限，0-14％均可。一级三相混合反应器的循环料浆液固质量比为1.5-5，反应温度为75-100℃，磷酸的P2O5质量浓度为20-40％，排出尾气A1温度100-125℃；二级三相混合反应器的循环料浆液固比为4-50，最好是8-12，反应温度为60-100℃，排除尾气A2温度62-100℃；三级三相混合反应的循环料浆液固比为5-60，最好是20-25，反应温度为50-85℃，排出尾气A3温度52-95℃，气相中SO2体积浓度低到100PPM以下。从三级三相混合反应器出来的尾气A3送到湿法磷酸尾气处理工序洗涤降温，回收其中的F。
作为优选的技术方案：所述的气、液、固三相混合分解和化学反应吸收装置为单级、或多级串联装置，或由多级混合分解反应装置集合成的一体化设备；磷矿浆的液：固比在1：1-5的范围，最好是1：2-3，温度常温，细度是过80-200目；磷石膏分解气进入三相混合反应器的SO2原始浓度不受限制。
作为进一步优选的技术方案：所述的气、液、固三相混合分解和化学反应吸收装置为多级串联装置。
作为优选的技术方案：步骤(3)所述的混合分解和吸收化学反应产生的过量热量经过换热器移走并进行回收。
作为优选的技术方案：步骤(3)中，混合分解反应产生的亚硫酸钙，在反应生产装置中加入空气，氧化成硫酸钙。
作为优选的技术方案：步骤(3)所述的混合分解和吸收化学反应氧化得到的料浆C，送湿法磷酸装置生产并分离出湿法磷酸和磷 石膏。
与现有技术相比，本发明的优点在于：由于石膏分解气直接用于湿法磷酸生产，分解气不再加工成硫酸，取消了生产硫酸的中间过程，省去了生产硫酸的装置与生产投资，科学合理利用了磷矿与石膏分解气酸碱化学位能，大大简化了磷石膏硫资源循环利用生产湿法磷酸的工艺流程，减少所有生产硫酸的设备与装置，工艺简单，生产成本低，具有显著的技术和经济效益。同时，由于三相混合反应对于磷石膏分解气中SO2浓度范围无要求，放宽了磷石膏还原分解的制气的操作条件。本方法也为超低浓度的SO2的回收利用开辟了一个新途径，达到了节约能源、降低生产成本，提高生产效率，减少投资，增加生产。
附图说明
图1：本发明的流程示意图
1、球磨机；2、磷矿浆贮槽；3、磷矿浆泵；4、一级三相混合反应器；5、一级循环泵；6、二级三相混合反应吸收器；7、二级循环泵；8、三级三相混合反应器；9、三级循环泵；10、磷酸料浆贮槽；11、磷酸料浆泵；12、换热装置I；13、换热装置II；14、换热装置III；15、旋风除尘器；16-19悬浮预热器。
具体实施方式
下面结合工艺流程图并用具体实施例对本发明方法作进一步说明。
实施例1
将磷矿36219.6公斤和水加入到磨机1中，制成磷矿浆B，其水分按质量百分比计为70％，将磷矿浆B置于磷矿浆贮槽2中待用，所述磷矿的组成见表1-1:
表1-1：磷矿组成表(质量百分比)
成分 P2O5 Fe2O3 Al2O3 CaO MgO CO2 SO3 F A.I H2O
组成％ 30.87 2.23 0.84 42.46 0.38 0.72 0.15 2.2 19.66 1.35
磷石膏分解气S从分解煅烧窑出来，经过悬浮预热器16-19换热后，气体温度降到320℃，每小时产出分解气2530.52Kmol气体，其组成见表1-2。
表1-2、分解气S组成表
成分 CO2 SO2 N2 O2 H2O 合计
体积％ 16.1 11.1 58.7 0.6 13.5 100
Kmol 497.41 280.89 1485.42 15.18 341.62 2530.52
该气体进入通过换热器装置Ⅰ12冷却降温后温度达85℃，换下的热量送去热能回收，然后分解气S进入一级三相混合反应器4中与一级循环泵5送入的循环反应料浆进行固、液、气三相混合化学反应，分解气S中的SO2与液体中钙离子生成CaSO3进而在空气的作用下氧化成CaSO4，一级三相混合反应器4的循环料浆温度95℃，其P2O5浓度38％，液固比为3,同时在一级三相混合反应器4内每小时鼓入空气1230.30Kmol；从一级三相混合反应器4每小时排出175302.86公斤磷料浆C1溢流到磷酸料浆贮槽10，然后通过磷酸料浆泵11送 去湿法磷酸装置进行微调后，料浆送去分离固相硫酸钙，从而得到成品磷酸27952.48公斤，其P2O5浓度38％。
从一级三相混合反应4器排出的尾气A1的气体温度85℃，气体组成见表1-3：
表1-3、一级三相混合反应器排出气体尾气A1组成表
成分 CO2 SO2 N2 O2 H2O F 合计
体积％ 8.98 0.49 54.12 3.18 33.21 0.02 100
Kmol 407.71 22.47 2457.56 144.39 1508.12 0.84 4541.09
从一级三相混合反应器出来的气体4541.09Kmol进入二级三相混合反应器6，气体中的SO2继续与二级循环泵7送入的循环料浆进行反应，生成CaSO3，二级三相混合反应器6温度95℃，反应后料浆过多的热量用13换热装置Ⅱ移走并回收热量，从二级三相混合反应器6出来的磷料浆175647.63公斤溢流到第一级三相混合反应器4，同时177647.48公斤料浆从三级三相混合反应器8溢流到二级三相混合反应器6，从二级三相混合反应器6出来的尾气A2温度85℃，气体组成见表1-4。
表1-4、二级三相混合反应器排除气体尾气A2组成表
成分 CO2 SO2 N2 O2 H2O F 合计
体积％ 8.66 0.04 52.14 2.84 36.29 0.03 100
Kmol 408.01 1.8 2457.56 134.06 1710.35 1.26 4713.04
从二级三相混合反应器出来的气体A24713.04Kmol进入三级三相混合反应器8，与由三级循环泵9送入的循环料浆反应，气体A2中的SO2生成CaSO3，反应料浆中过多的热量用14换热装置Ⅲ移走热量并回收，三级三相混合反应器8的温度95℃，排除出料浆177647.48公斤溢流到二级三相混合反应器6，从湿法磷酸磷石膏分离装置出来的淡酸127348.74公斤加入到三级三相混合反应器8，磷矿浆加入量为51742公斤,从三级三相混合反应器出来的气体尾气A3温度85℃，气体组成见表1-5；送湿法磷酸尾气系统处理其中氟化物。
表1-5、出第三吸收器的气体尾气A3组成表
成分 CO2 SO2 N2 O2 H2O F 合计
体积％ 8.77 0.04 52.13 2.84 36.19 0.04 100
Kmol 413.34 1.80 2457.56 134.06 1706.27 1.68 4714.71
实施例2
将磷矿21357.24公斤和水加入到磨机1中，制成磷矿浆，其水分70％，将磷矿浆置于磷矿浆贮槽2中待用，其磷矿的组成见表2-1。
表2-1：磷矿组成表(质量百分比)
成分 P2O5 Fe2O3 Al2O3 CaO MgO CO2 SO3 F A.I H2O
组成％ 33.44 1.63 1.58 48.98 1.29 4.12 0.46 2.2 4.96 5.09
磷石膏分解煅烧窑出来的分解气S，经过悬浮预热器16-19换热后，气体温度降到330℃。每小时产出2106.7Kmol气体，其组成见表2-2。
表2-2、分解气S组成表
成分 CO2 SO2 N2 O2 H2O 合计
体积％ 16 10 61.7 0.8 11.5 100
Kmol 337.07 210.67 1299.83 16.85 242.27 2106.7
分解气S通过12换热装置Ⅰ再降温后温度达86℃，并回收其热量，然后分解气S进入一级三相混合反应器4与一级循环泵5送入的循环反应料浆进行固、液、气三相混合化学反应，分解气S中的SO2与液体中钙离子生成CaSO3并在三相混合反应器4内同时鼓入空气1003.17Kmol，进而氧化CaSO3成CaSO4，一级三相混合反应器4的循环料浆温度96℃，其P2O5浓度为40％，液固比为3；从一级三相混合反应器4出来的83720.38公斤磷料浆C1溢流到磷料浆收集槽，送湿法磷酸装置通过调整后，料浆送去分离固相硫酸钙，从而得到成品磷酸16961.92公斤，其P2O5浓度40％。
从一级三相混合反应器出来的尾气A1的温度86℃，组成见表2-3；
表2-3、一级三相混合反应器排出尾气A1组成表
成分 CO2 SO2 N2 O2 H2O F 合计
体积％ 8.53 0.53 52.78 3.35 34.80 0.02 100
Kmol 338.07 21.07 2092.33 132.72 1379.62 0.73 3964.54
从一级三相混合反应器4排出的气体A13964.54Kmol进入二级三相混合反应器6，气体中的SO2继续与二级循环泵7送入的循环料浆进行反应，生成CaSO3，二级三相混合反应器6温度96℃，反应后料浆过多的热量用13换热装置Ⅱ移走并回收热量，从二级三相混合反应器6出来的磷料浆105563.87公斤溢流到一级三相混合反应器4，同时97487.01公斤料浆从三级三相混合反应器8溢流到二级三相混合反应器6，从二级三相混合反应器6出来的尾气A2温度86℃，气体组成见表2-4。
表2-4、二级三相混合反应器排出的尾气A2组成表
成分 CO2 SO2 N2 O2 H2O F 合计
体积％ 8.42 0.05 51.98 3.06 36.46 0.03 100
Kmol 339.07 2.11 2092.33 123.24 1467.75 1.10 4025.6
从二级三相混合反应器出来的气体A24025.6Kmol进入三级三相混合反应器8，与由三级循环泵9送入的循环料浆反应，气体A2中的SO2生成CaSO3，反应料浆中过多的热量用14换热装置Ⅲ移走热量并回收，三级三相混合反应器8的温度96℃，排除出料浆97487.01公斤溢流到二级三相混合反应器6；从湿法磷酸磷石膏分离装置出来的淡酸66438.15公斤加入到三级三相混合反应器8，磷矿浆加入量为51742公斤,从三级三相混合反应器出来的尾气A3温度85℃，气体组成见表1-5；送湿法磷酸尾气系统处理其中氟化物。
表2-5、三级三相混合反应器排出的尾气A3组成表
成分 CO2 SO2 N2 O2 H2O F 合计
组成％ 8.51 0.01 52.51 3.07 35.87 0.04 100
Kmol 339.07 0.21 2092.33 122.29 1429.07 1.47 3984.77
。

Claims (10)

  1. 一种磷石膏分解气直接用于湿法磷酸生产的方法，其特征在于，包括以下步骤：
    (1)、将磷矿经过湿法研磨制备得到磷矿浆B；
    (2)、制备石膏分解气S，所述石膏分解气S，为将磷石膏，或天然石膏，或热电厂脱硫石膏，或硫酸法钛白废酸处理石膏，或其它工业副产石膏进行还原分解而产生；
    (3)、将步骤(2)所得的分解气S用步骤(1)所得的磷矿浆B直接进行气、液、固三相混合分解和吸收化学反应，得到尾气A和含硫酸钙的磷酸料浆C；
    (4)将步骤(3)所得的磷石膏再进行还原分解生产分解气S，用于步骤(3)。
  2. 根据权利要求1所述的磷石膏分解气直接用于湿法磷酸生产的方法，其特征在于：步骤(1)所得磷矿浆B的液：固质量比为1：(1-5)；磷矿浆B的颗粒细度为80-250目。
  3. 根据权利要求2所述的磷石膏分解气直接用于湿法磷酸生产的方法，其特征在于：步骤(1)所得磷矿浆B的液：固质量比为1：(2.5-4)。
  4. 根据权利要求1所述的磷石膏分解气直接用于湿法磷酸生产的方法，其特征在于：所述石膏分解气S中SO2体积百分浓度为0-14％。
  5. 根据权利要求4所述的磷石膏分解气直接用于湿法磷酸生产 的方法，其特征在于：所述石膏分解气S中SO2体积百分浓度为5-11％。
  6. 根据权利要求1所述的磷石膏分解气直接用于湿法磷酸生产的方法，其特征在于：所述的气、液、固三相混合分解和化学反应吸收装置为单级、或多级串联装置，或由多级混合分解反应装置集合成的一体化设备。
  7. 根据权利要求1所述的磷石膏分解气直接用于湿法磷酸生产的方法，其特征在于：所述的气、液、固三相混合分解和化学反应吸收装置为多级串联装置。
  8. 根据权利要求1所述的磷石膏分解气直接用于湿法磷酸生产的方法，其特征在于：步骤(3)所述的混合分解和吸收化学反应产生的过量热量经过换热器移走并进行回收。
  9. 根据权利要求1所述的磷石膏分解气直接用于湿法磷酸生产的方法，其特征在于：步骤(3)中，混合分解反应产生的亚硫酸钙，在反应生产装置中加入空气，氧化成硫酸钙。
  10. 根据权利要求1所述的磷石膏分解气直接用于湿法磷酸生产的方法，其特征在于：步骤(3)所述的混合分解和吸收化学反应氧化得到的料浆C，送湿法磷酸装置生产并分离出湿法磷酸和磷石膏。
PCT/CN2016/083255 2016-04-08 2016-05-25 一种磷石膏分解气直接用于湿法磷酸生产的方法 WO2017173717A1 (zh)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CN201610218410.2 2016-04-08
CN201610218410.2A CN105836722A (zh) 2016-04-08 2016-04-08 一种磷石膏分解气直接用于湿法磷酸生产的方法

Publications (1)

Publication Number Publication Date
WO2017173717A1 true WO2017173717A1 (zh) 2017-10-12

Family

ID=56597131

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2016/083255 WO2017173717A1 (zh) 2016-04-08 2016-05-25 一种磷石膏分解气直接用于湿法磷酸生产的方法

Country Status (2)

Country Link
CN (1) CN105836722A (zh)
WO (1) WO2017173717A1 (zh)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109912245A (zh) * 2019-04-26 2019-06-21 四川绵竹市盘龙矿物质有限责任公司 一种硫酸生产联产石膏粉的方法及装置
CN113860269A (zh) * 2021-10-25 2021-12-31 云南云天化环保科技有限公司 一种磷石膏分段制备硫酸和矿渣棉纤维的方法及其装置

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106276831B (zh) * 2016-08-24 2019-11-26 湖北三宁化工股份有限公司 一种利用so2气体和磷矿浆反应生产磷酸的方法及装置
CN112934906A (zh) * 2019-12-11 2021-06-11 西南科技大学 一种利用灼烧生料无害化处理磷尾矿和磷石膏的方法
CN112250051B (zh) * 2020-10-16 2023-08-22 昆明理工大学 一种磷矿浆吸收磷石膏焙烧烟气联产磷酸和水泥熟料的方法

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1899668A (zh) * 2006-06-30 2007-01-24 昆明理工大学 磷矿浆催化氧化脱除低浓度二氧化硫的方法
CN103191637A (zh) * 2013-04-23 2013-07-10 瓮福（集团）有限责任公司 一种工业尾气脱硫装置
CN203108430U (zh) * 2013-03-19 2013-08-07 瓮福（集团）有限责任公司 一种磷精矿脱除低浓度二氧化硫的装置
CN103964715A (zh) * 2014-02-27 2014-08-06 龚家竹 节能降耗的石膏生产水泥联产硫酸的方法
CN104556189A (zh) * 2014-12-25 2015-04-29 湖北祥云(集团)化工股份有限公司 一种生产湿法磷酸副产品白石膏的方法
CN104667728A (zh) * 2015-01-26 2015-06-03 昆明川金诺化工股份有限公司 一种脱除硫酸尾气中二氧化硫的方法

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1899668A (zh) * 2006-06-30 2007-01-24 昆明理工大学 磷矿浆催化氧化脱除低浓度二氧化硫的方法
CN203108430U (zh) * 2013-03-19 2013-08-07 瓮福（集团）有限责任公司 一种磷精矿脱除低浓度二氧化硫的装置
CN103191637A (zh) * 2013-04-23 2013-07-10 瓮福（集团）有限责任公司 一种工业尾气脱硫装置
CN103964715A (zh) * 2014-02-27 2014-08-06 龚家竹 节能降耗的石膏生产水泥联产硫酸的方法
CN104556189A (zh) * 2014-12-25 2015-04-29 湖北祥云(集团)化工股份有限公司 一种生产湿法磷酸副产品白石膏的方法
CN104667728A (zh) * 2015-01-26 2015-06-03 昆明川金诺化工股份有限公司 一种脱除硫酸尾气中二氧化硫的方法

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109912245A (zh) * 2019-04-26 2019-06-21 四川绵竹市盘龙矿物质有限责任公司 一种硫酸生产联产石膏粉的方法及装置
CN109912245B (zh) * 2019-04-26 2024-04-12 四川绵竹市盘龙矿物质有限责任公司 一种硫酸生产联产石膏粉的方法及装置
CN113860269A (zh) * 2021-10-25 2021-12-31 云南云天化环保科技有限公司 一种磷石膏分段制备硫酸和矿渣棉纤维的方法及其装置
CN113860269B (zh) * 2021-10-25 2023-06-16 云南云天化环保科技有限公司 一种磷石膏分段制备硫酸和矿渣棉纤维的方法及其装置

Also Published As

Publication number Publication date
CN105836722A (zh) 2016-08-10

Similar Documents

Publication Publication Date Title
WO2017173717A1 (zh) 一种磷石膏分解气直接用于湿法磷酸生产的方法
CN103303877B (zh) 多气源低浓度so2烟气综合回收制酸工艺流程
CN101508447B (zh) 一种处理磷石膏的方法
WO2017173716A1 (zh) 一种磷石膏分解气联合湿法磷酸生产的方法
CN103408052B (zh) 一种磷石膏的分解方法
CN109626339B (zh) 一种石膏制备硫酸的方法
CN103224221A (zh) 一种利用一水硫酸亚铁渣分离硫酸与硫酸亚铁的方法
CN104843749A (zh) 一种利用氧化镁脱硫废液、废渣制备胶凝材料原料的方法
CN112299386A (zh) 一种磷矿浆脱除湿法稀磷酸中硫酸根的方法
CN103232053A (zh) 用处理工业含氟废水产生的底泥生产氟化钙的方法
CN102775082A (zh) 一种白水泥、硫酸的生产方法
CN100453450C (zh) 一种磷石膏与硫磺结合制酸联产水泥的工艺方法
CN104016357B (zh) 一种锰渣综合利用生产化工原料的方法
CN106396440A (zh) 废气废渣综合利用的方法
CN115925297B (zh) 一种酸性磷石膏煅烧净化方法
CN112250051B (zh) 一种磷矿浆吸收磷石膏焙烧烟气联产磷酸和水泥熟料的方法
CN101890289A (zh) 一种淬渣水溶液用于烟气脱硫的工艺
CN115893884A (zh) 一种酸性磷石膏煅烧净化系统及方法
CN104085866A (zh) 一种提高磷酸品质和收率的生产方法
CN210885316U (zh) 稳定高效的湿法磷酸生产系统
CN203525549U (zh) 一种用于烟气脱硫脱氮的设备
JP2004073976A (ja) 廃石膏製品の処理方法
CN112723329B (zh) 一种湿法磷酸的生产方法
AU2022202129B2 (en) Polluted co2 capturing with lime produced from phosphogypsum calcination using sulfur as non-co2 fuel
CN104496605B (zh) 一种回收利用炉气中二氧化硫生产碱性肥料的方法及装置

Legal Events

Date Code Title Description
NENP Non-entry into the national phase

Ref country code: DE

121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 16897650

Country of ref document: EP

Kind code of ref document: A1

122 Ep: pct application non-entry in european phase

Ref document number: 16897650

Country of ref document: EP

Kind code of ref document: A1