CN112898073A - Method for preparing NPK compound fertilizer by using phosphate tailings and potassium feldspar - Google Patents

Method for preparing NPK compound fertilizer by using phosphate tailings and potassium feldspar Download PDF

Info

Publication number
CN112898073A
CN112898073A CN202110048932.3A CN202110048932A CN112898073A CN 112898073 A CN112898073 A CN 112898073A CN 202110048932 A CN202110048932 A CN 202110048932A CN 112898073 A CN112898073 A CN 112898073A
Authority
CN
China
Prior art keywords
compound fertilizer
potassium feldspar
filtrate
leaching
surfactant
Prior art date
Legal status (The legal status 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 status listed.)
Granted
Application number
CN202110048932.3A
Other languages
Chinese (zh)
Other versions
CN112898073B (en
Inventor
赵俊华
马家玉
李丽
汪铁林
宋开荣
王存文
覃远航
孟宪涛
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Xiangyang Zedong Chemical Group Co ltd
Wuhan Institute of Technology
Original Assignee
Xiangyang Zedong Chemical Group Co ltd
Wuhan Institute of Technology
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 Xiangyang Zedong Chemical Group Co ltd, Wuhan Institute of Technology filed Critical Xiangyang Zedong Chemical Group Co ltd
Priority to CN202110048932.3A priority Critical patent/CN112898073B/en
Publication of CN112898073A publication Critical patent/CN112898073A/en
Application granted granted Critical
Publication of CN112898073B publication Critical patent/CN112898073B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C05—FERTILISERS; MANUFACTURE THEREOF
    • C05B—PHOSPHATIC FERTILISERS
    • C05B17/00—Other phosphatic fertilisers, e.g. soft rock phosphates, bone meal
    • C—CHEMISTRY; METALLURGY
    • C05—FERTILISERS; MANUFACTURE THEREOF
    • C05G—MIXTURES OF FERTILISERS COVERED INDIVIDUALLY BY DIFFERENT SUBCLASSES OF CLASS C05; MIXTURES OF ONE OR MORE FERTILISERS WITH MATERIALS NOT HAVING A SPECIFIC FERTILISING ACTIVITY, e.g. PESTICIDES, SOIL-CONDITIONERS, WETTING AGENTS; FERTILISERS CHARACTERISED BY THEIR FORM
    • C05G3/00—Mixtures of one or more fertilisers with additives not having a specially fertilising activity
    • C—CHEMISTRY; METALLURGY
    • C05—FERTILISERS; MANUFACTURE THEREOF
    • C05G—MIXTURES OF FERTILISERS COVERED INDIVIDUALLY BY DIFFERENT SUBCLASSES OF CLASS C05; MIXTURES OF ONE OR MORE FERTILISERS WITH MATERIALS NOT HAVING A SPECIFIC FERTILISING ACTIVITY, e.g. PESTICIDES, SOIL-CONDITIONERS, WETTING AGENTS; FERTILISERS CHARACTERISED BY THEIR FORM
    • C05G3/00—Mixtures of one or more fertilisers with additives not having a specially fertilising activity
    • C05G3/50—Surfactants; Emulsifiers
    • C—CHEMISTRY; METALLURGY
    • C05—FERTILISERS; MANUFACTURE THEREOF
    • C05G—MIXTURES OF FERTILISERS COVERED INDIVIDUALLY BY DIFFERENT SUBCLASSES OF CLASS C05; MIXTURES OF ONE OR MORE FERTILISERS WITH MATERIALS NOT HAVING A SPECIFIC FERTILISING ACTIVITY, e.g. PESTICIDES, SOIL-CONDITIONERS, WETTING AGENTS; FERTILISERS CHARACTERISED BY THEIR FORM
    • C05G5/00—Fertilisers characterised by their form
    • C05G5/10—Solid or semi-solid fertilisers, e.g. powders
    • C05G5/12—Granules or flakes
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P10/00—Technologies related to metal processing
    • Y02P10/20—Recycling

Landscapes

  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Pest Control & Pesticides (AREA)
  • Fertilizers (AREA)

Abstract

The invention discloses a method for preparing NPK compound fertilizer by using phosphate tailings and potassium feldspar, which comprises the following steps: mixing the ground phosphate tailings and potash feldspar with hydrochloric acid and a surfactant, blending, carrying out leaching reaction at 20-40 ℃, and carrying out solid-liquid separation after 1-3 hours to obtain leaching slag and leaching liquid; adding hydrochloric acid and a surfactant into the obtained leaching solution, then performing recycling treatment on the next batch of minerals, and performing solid-liquid separation after repeating for a plurality of times to obtain filter residues and a filtrate enriched with phosphorus and potassium; sequentially removing calcium from the filtrate by using sulfuric acid, and neutralizing by using ammonia water to remove aluminum, iron and magnesium to obtain refined filtrate; and (4) evaporating, concentrating and granulating the refined filtrate to prepare the low-chlorine high-concentration NPK compound fertilizer. The invention can obviously improve the leaching rate of potassium and phosphorus by adding the surfactant in the acid leaching process, simultaneously reduce the adding amount of hydrochloric acid, and can prepare the high-phosphorus low-chlorine compound fertilizer without a chlorine removal process and a phosphorus supplement process.

Description

Method for preparing NPK compound fertilizer by using phosphate tailings and potassium feldspar
Technical Field
The invention relates to the technical field of inorganic chemical industry, in particular to a method for preparing an NPK compound fertilizer by using phosphate tailings and potassium feldspar.
Background
The phosphate tailings refer to "wastes" generated by mineral separation enterprises under certain technical conditions after mineral concentrate separation, and belong to mining solid wastes in industrial waste materials. With the continuous development of the phosphorus chemical industry in China, a large amount of phosphorus tailings are generated every year. At present, the treatment and utilization of the phosphate tailings are not effectively developed. The waste phosphate tailings are piled up, which not only occupies land and causes serious pollution to the surrounding environment, but also causes the loss of a large amount of useful elements in the tailings. The tailings are used as potential secondary mineral resources, useful element phosphorus in the tailings can be comprehensively recovered, a series of materials with low or high added values are prepared, the comprehensive utilization of the tailings can solve the problems of stacking and environmental pollution, the sustainable development of the mineral resources can be ensured, the social development is promoted, and important economic benefits are obtained. Currently, phosphorus chemical industry enterprises in China face double pressure of resources and environment, and sustainable development is seriously challenged; the industrial chain is not perfect, the product structure is not rich, and the added value of the product is low. At present, an effective technology is lacked for high-valued utilization of the phosphate tailings, and reasonable connection of upstream and downstream industries is realized.
The phosphate fertilizer and the potash fertilizer are used as nutrient element fertilizers of crops and play an extremely important role in the life metabolic process of the crops. In China, the yield and the dosage of potassium fertilizer and compound fertilizer are insufficient, the proportion of nitrogen, phosphorus and potassium in the applied fertilizer is seriously disordered, and the phenomena of rich nitrogen, little phosphorus and potassium deficiencySevere. The extraction of potassium mainly comes from soluble sylvite deposits, but China is seriously poor and the distribution is very uneven. According to statistics, the storage capacity of the water-soluble potassium salt in the world of 2012 is converted into K2The O accounts for 95.52 hundred million tons, the Chinese accounts for 2.1 hundred million tons, accounts for about 2.2 percent of the total reserves in the world, is mainly distributed in the Qinghai Kerr salt lake and the Xinjiang Apocynum venetum salt lake, and is inconvenient to develop and utilize. The water-insoluble potassium-containing ore beds in China are abundant, the reserves exceed 200 hundred million tons, and the potassium feldspar is mostly distributed in middle and eastern agriculture developed areas in the form of potassium feldspar. At present, the demand of potassium is large in China, the domestic market gap is huge, and a large amount of potassium fertilizer is imported every year. If the non-soluble potassium resource with huge reserves, such as potassium feldspar, can be changed into soluble potassium, the method has great significance.
Therefore, how to efficiently and economically utilize the phosphorus tailings and the potassium feldspar to prepare the NPK compound fertilizer and simultaneously improve the utilization rate of phosphorus and potassium is a difficult task for modern chemical engineering technologists.
Disclosure of Invention
In view of the above, there is a need to provide a method for preparing an NPK compound fertilizer from phosphate tailings and potassium feldspar, so as to solve the technical problem of the prior art that phosphorus and potassium elements in the phosphate tailings and the potassium feldspar are wasted.
The invention provides a method for preparing an NPK compound fertilizer by using phosphate tailings and potassium feldspar, which comprises the following steps:
(1) acid leaching: mixing the ground phosphate tailings and potash feldspar with hydrochloric acid and a surfactant, blending, carrying out leaching reaction at 20-40 ℃, and carrying out solid-liquid separation after 1-3 hours to obtain leaching slag and leaching liquid; wherein the surfactant is sodium dodecyl benzene sulfonate and dodecyl betaine according to the weight ratio of 1: (0.2-0.4) in mass ratio;
(2) leaching liquor is circularly leached: adding hydrochloric acid and a surfactant into the leachate obtained in the step (1), then recycling the leachate to treat the next batch of minerals, and after repeating the step (1) for a plurality of times, carrying out solid-liquid separation to obtain filter residues and a filtrate enriched with phosphorus and potassium;
(3) purifying the filtrate: sequentially removing calcium from the filtrate obtained in the step (2) by using sulfuric acid, and neutralizing by using ammonia water to remove aluminum, iron and magnesium to obtain refined filtrate;
(4) preparing an NPK compound fertilizer: and (4) evaporating, concentrating and granulating the filtrate obtained in the step (3) to prepare the low-chlorine high-concentration NPK compound fertilizer.
Compared with the prior art, the invention has the beneficial effects that:
(1) the method can decompose the potassium feldspar by utilizing the fluorine in the phosphate tailings without additionally adding fluorine resources, and has low decomposition temperature, and the acid and the fluorine in the system can be recycled;
(2) according to the invention, the surfactant is added in the acid leaching process, so that the leaching rate of potassium and phosphorus can be obviously improved, the addition amount of hydrochloric acid is reduced, and the high-phosphorus low-chlorine compound fertilizer can be prepared without a chlorine removal process and a phosphorus supplement process;
(3) the lixiviant hydrochloric acid used in the invention has wide sources, is an industrial byproduct, and solves the problem of the outlet of the byproduct hydrochloric acid;
(4) the process does not relate to high temperature and high pressure, a plurality of production devices can refer to inorganic chemical industries such as wet-process phosphoric acid, soda chemical industry and the like, and the process is easy to implement;
(5) the invention can be used for treating potassium feldspar, and can also be used for treating various potassium-containing ores such as clay, nepheline and the like.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail with reference to the following embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
The invention provides a method for preparing an NPK compound fertilizer by using phosphate tailings and potassium feldspar, which comprises the following steps:
(1) acid leaching: mixing the ground phosphate tailings and potash feldspar with hydrochloric acid and a surfactant, blending, carrying out leaching reaction at 20-40 ℃, and carrying out solid-liquid separation after 1-3 hours to obtain leaching slag and leaching liquid; wherein the surfactant is sodium dodecyl benzene sulfonate and dodecyl betaine according to the weight ratio of 1: (0.2-0.4) in mass ratio;
(2) leaching liquor is circularly leached: adding hydrochloric acid and a surfactant into the leachate obtained in the step (1), then recycling the leachate to treat the next batch of minerals, and after repeating the step (1) for a plurality of times, carrying out solid-liquid separation to obtain filter residues and a filtrate enriched with phosphorus and potassium;
(3) purifying the filtrate: sequentially removing calcium from the filtrate obtained in the step (2) by using sulfuric acid, and neutralizing by using ammonia water to remove aluminum, iron and magnesium to obtain refined filtrate;
(4) preparing an NPK compound fertilizer: and (4) evaporating, concentrating and granulating the filtrate obtained in the step (3) to prepare the low-chlorine high-concentration NPK compound fertilizer.
Since potassium feldspar has a stable structure and does not generally react with other acids except hydrofluoric acid, hydrofluoric acid or fluoride salt (such as calcium fluoride) and other acids (such as sulfuric acid, phosphoric acid and hydrochloric acid) are added in the process of decomposing potassium feldspar by acid. The method utilizes the reaction of hydrochloric acid and fluorine in the phosphorus tailings to generate hydrogen fluoride to decompose potassium feldspar in the phosphorus-potassium associated ore, and fluorosilicate formed by the reaction further participates in the decomposition of the potassium feldspar in the phosphorus-potassium associated ore; meanwhile, the surfactant is added in the acid leaching process, so that the leaching rate of potassium and phosphorus can be obviously improved, the phosphorus and potassium content in the compound fertilizer is improved, the reaction condition is mild, and the reaction time is short; in addition, due to the addition of the surfactant, the addition amount of hydrochloric acid is reduced, and the low-chlorine compound fertilizer can be prepared without a dechlorination process.
In the invention, P in the phosphate tailings selected in the step (1) is2O55-20 wt% of CaO, 30-50 wt% of CaO and 0.5-5 wt% of F; k in selected potassium feldspar2The content of O is 7-15 wt%; the mass ratio of the phosphate tailings to the potassium feldspar is (2-5): 1; the concentration of hydrochloric acid is 20-30%, and the dosage ratio of the phosphate tailings, the potassium feldspar and the hydrochloric acid is 1 g: (2-4) ml; the mass ratio of the phosphate tailings, the potassium feldspar and the surfactant is 1000: (0.1-0.3).
Further, the mass ratio of the sodium dodecyl benzene sulfonate to the dodecyl betaine is 1: 0.3. Under the condition of the proportion, the dissolution effect of potassium and phosphorus is optimal.
According to the invention, the filtrate is circularly treated, so that the chlorine content in the compound fertilizer can be effectively reduced, and the phosphorus and potassium content in the filtrate can be increased, but the number of times of circular treatment is not too large, so that the mineral treatment effect is weakened. In the embodiment of the invention, the frequency of repeating the step (1) after adding hydrochloric acid and a surfactant in the step (2) and recycling the next batch of minerals is 2-4 times.
Further, in the step (2), the mass ratio of the phosphorus tailings to the potassium feldspar in the next batch of processed minerals is (1-2.5): 1, the adding amount of each time of the mixture is 1.3-1.7 times of the total amount of the ore in the step (1); the hydrochloric acid replenished each time accounts for 10-20% of the adding amount of the hydrochloric acid in the step (1); and (3) the surfactant supplemented in the step (2) accounts for 10-20% of the addition of the surfactant in the step (1).
In the invention, the calcium sulfate removal in the step (3) is specifically as follows: according to n (Ca)2+):n(SO4 2-) 1: (0.8-1.2) adding a sulfuric acid solution with the mass concentration of 50-98%, and reacting at 30-90 ℃ for 0.5-3 h; in the reaction process, the stirring speed is 400-1000 r/min. The ammonia water neutralization aluminum, iron and magnesium removal specifically comprises the following steps: the pH value is adjusted to 3.5 by using an ammonia water solution to precipitate for iron removal, then the pH value is adjusted to 6.5 to precipitate for aluminum removal, and finally the pH value is adjusted to 9 to precipitate for magnesium removal. In the reaction process (such as calcium removal by sulfuric acid and the like), the generated hydrogen chloride overflows and can be absorbed by the tail gas absorption device, so that the cyclic utilization of the hydrochloric acid is facilitated, and the chlorine content in the compound fertilizer is reduced.
In order to avoid redundancy, in the following examples and comparative examples of the present invention, some of the raw materials are summarized as follows:
phosphate tailings: the main chemical component is P2O5 16.3％、CaO 35.2％、MgO 10.42％、Al2O3 5.43％、F 3.2％；
Potassium feldspar: the main chemical component is K2O 12.76％、Na2O 5.63％Al2O3 16.62％SiO2 63.23％；
The mesh number of the phosphate tailings and the potassium feldspar is 200-400 meshes.
Example 1
(1) Acid leaching: mixing 60g of ground phosphate tailings, 20g of potassium feldspar, 240mL of hydrochloric acid solution (the mass concentration is 25 percent) and 0.016g of surfactant (the mass ratio of sodium dodecyl benzene sulfonate to dodecyl betaine is 1: 0.3), carrying out leaching reaction at 30 ℃, and carrying out solid-liquid separation after 2 hours to obtain leaching residues and leaching liquid;
(2) leaching liquor is circularly leached: supplementing acid to the leachate obtained in the step (1), then recycling the next batch of minerals, and repeating the step (1) for 4 times to separate solid from liquid to obtain filter residue and P, K-enriched filtrate; in the process, 80g of phosphorus tailings, 30g of potassium feldspar, 48mL of hydrochloric acid solution (the mass concentration is 25%) and 0.0024g of surfactant (the mass ratio of sodium dodecyl benzene sulfonate to dodecyl betaine is 1: 0.3) are added each time;
(3) purifying the filtrate: the filtrate obtained in the step (2) is processed according to the formula of n (Ca)2+):n(SO42-) Adding a sulfuric acid solution with the mass concentration of 85% at the ratio of 1:1, carrying out calcium removal reaction at 50 ℃ under the stirring condition of 500 revolutions per minute, and carrying out solid-liquid separation after 2 hours of reaction; adding ammonia water into the obtained filtrate to slowly adjust the pH value to 3.5 to generate white precipitate, continuously adding ammonia water into the filtrate after filtration and separation to adjust the pH value to 6.5 to generate white precipitate, adding ammonia water into the filtrate after filtration and separation again to adjust the pH value to 9 to generate white precipitate, and filtering and separating to obtain filter residue and purified filtrate;
(4) preparing an NPK compound fertilizer: evaporating, concentrating and granulating the purified filtrate obtained in the step (3) at 100 ℃ to prepare 160.4g of NPK compound fertilizer, and detecting N, P in the compound fertilizer2O5、K2The contents of O and Cl are respectively 16.8%, 35.1%, 8.9% and 2.4%, which meet the national standard and belong to low-chlorine NPK compound fertilizer.
Example 2
(1) Acid leaching: mixing 50g of ground phosphate tailings, 10g of potassium feldspar, 120mL of hydrochloric acid solution (the mass concentration is 30 percent) and 0.006g of surfactant (the mass ratio of sodium dodecyl benzene sulfonate to dodecyl betaine is 1: 0.2), carrying out leaching reaction at 20 ℃, and carrying out solid-liquid separation after 3 hours to obtain leaching residues and leaching liquid;
(2) leaching liquor is circularly leached: supplementing acid to the leachate obtained in the step (1), then recycling the next batch of minerals, and repeating the step (1) for 2 times to separate solid from liquid to obtain filter residue and P, K-enriched filtrate; in the process, 60g of phosphorus tailings, 40g of potassium feldspar, 24mL of hydrochloric acid solution (the mass concentration is 30%) and 0.0012g of surfactant (the ratio of sodium dodecyl benzene sulfonate to dodecyl betaine is 1: 0.2) are supplemented each time;
(3) purifying the filtrate: the filtrate obtained in the step (2) is processed according to the formula of n (Ca)2+):n(SO42-) Adding 50% sulfuric acid solution at a ratio of 1:0.8, performing calcium removal reaction at 90 ℃ under 500 r/min stirring, and performing solid-liquid separation after reaction for 0.5 h; adding ammonia water into the obtained filtrate to slowly adjust the pH value to 3.5 to generate white precipitate, continuously adding ammonia water into the filtrate after filtration and separation to adjust the pH value to 6.5 to generate white precipitate, adding ammonia water into the filtrate after filtration and separation again to adjust the pH value to 9 to generate white precipitate, and filtering and separating to obtain filter residue and purified filtrate;
(4) preparing an NPK compound fertilizer: evaporating, concentrating and granulating the purified filtrate obtained in the step (3) at 100 ℃ to prepare 104.6g of NPK compound fertilizer, and detecting N, P in the compound fertilizer2O5、K2The contents of O and Cl are respectively 20.4%, 23.2%, 8.4% and 7.5%, which meet the national standard and belong to low-chlorine NPK compound fertilizer.
Example 3
(1) Acid leaching: mixing 60g of ground phosphate tailings, 30g of potassium feldspar, 360mL of hydrochloric acid solution (the mass concentration is 20 percent) and 0.027g of surfactant (the mass ratio of sodium dodecyl benzene sulfonate to dodecyl betaine is 1: 0.4), carrying out leaching reaction at 40 ℃, and carrying out solid-liquid separation after 1 hour to obtain leaching slag and leaching liquid;
(2) leaching liquor is circularly leached: supplementing acid to the leachate obtained in the step (1), then recycling the next batch of minerals, and repeating the step (1) for 3 times to separate solid from liquid to obtain filter residue and P, K-enriched filtrate; in the process, 60g of phosphorus tailings, 60g of potassium feldspar, 36mL of hydrochloric acid solution (the mass concentration is 20%) and 0.0027g of surfactant (the mass ratio of sodium dodecyl benzene sulfonate to dodecyl betaine is 1: 0.4) are supplemented each time;
(3) purifying the filtrate: the filtrate obtained in the step (2) is processed according to the formula of n (Ca)2+):n(SO42-) Adding 98% sulfuric acid solution at a ratio of 1:1.2, and removing calcium at 30 deg.C under 500 r/min stirringReacting for 3h, and then carrying out solid-liquid separation; adding ammonia water into the obtained filtrate to slowly adjust the pH value to 3.5 to generate white precipitate, continuously adding ammonia water into the filtrate after filtration and separation to adjust the pH value to 6.5 to generate white precipitate, adding ammonia water into the filtrate after filtration and separation again to adjust the pH value to 9 to generate white precipitate, and filtering and separating to obtain filter residue and purified filtrate;
(4) preparing an NPK compound fertilizer: evaporating, concentrating and granulating the purified filtrate obtained in the step (3) at 100 ℃ to prepare 132.8g of NPK compound fertilizer, and detecting N, P in the compound fertilizer2O5、K2The contents of O and Cl are respectively 14.2%, 28.1%, 18.2% and 10.4%, which meet the national standard and belong to low-chlorine NPK compound fertilizer.
Comparative example 1
(1) Acid leaching: mixing 60g of ground phosphate tailings, 20g of potassium feldspar, 240mL of hydrochloric acid solution (the mass concentration is 25 percent) and 0.016g of sodium dodecyl benzene sulfonate, carrying out leaching reaction at 30 ℃, and carrying out solid-liquid separation after 2 hours to obtain leaching residues and leaching liquid;
(2) leaching liquor is circularly leached: supplementing acid to the leachate obtained in the step (1), then recycling the next batch of minerals, and repeating the step (1) for 4 times to separate solid from liquid to obtain filter residue and P, K-enriched filtrate; in the process, 80g of phosphorus tailings, 30g of potassium feldspar, 48mL of hydrochloric acid solution (with the mass concentration of 25 percent) and 0.0024g of sodium dodecyl benzene sulfonate are added each time;
(3) purifying the filtrate: the filtrate obtained in the step (2) is processed according to the formula of n (Ca)2+):n(SO42-) Adding a sulfuric acid solution with the mass concentration of 85% at the ratio of 1:1, carrying out calcium removal reaction at 50 ℃ under the stirring condition of 500 revolutions per minute, and carrying out solid-liquid separation after 2 hours of reaction; adding ammonia water into the obtained filtrate to slowly adjust the pH value to 3.5 to generate white precipitate, continuously adding ammonia water into the filtrate after filtration and separation to adjust the pH value to 6.5 to generate white precipitate, adding ammonia water into the filtrate after filtration and separation again to adjust the pH value to 9 to generate white precipitate, and filtering and separating to obtain filter residue and purified filtrate;
(4) preparing an NPK compound fertilizer: evaporating, concentrating and granulating the purified filtrate obtained in the step (3) at 100 ℃ to prepare 125.8g of NPK compound fertilizer, and detecting to obtain the NPK compound fertilizerN, P in fertilizer2O5、K2The O and Cl contents were 23.2%, 30.1%, 6.2% and 11.9%, respectively.
Comparative example 2
(1) Acid leaching: mixing 60g of ground phosphate tailings, 20g of potassium feldspar, 240mL of hydrochloric acid solution (the mass concentration is 25 percent) and 0.016g of dodecyl betaine, blending, carrying out leaching reaction at 30 ℃, and carrying out solid-liquid separation after 2 hours to obtain leaching residues and leaching liquid;
(2) leaching liquor is circularly leached: supplementing acid to the leachate obtained in the step (1), then recycling the next batch of minerals, and repeating the step (1) for 4 times to separate solid from liquid to obtain filter residue and P, K-enriched filtrate; in the process, 80g of phosphorus tailings, 30g of potassium feldspar, 48mL of hydrochloric acid solution (the mass concentration is 25 percent) and 0.0024g of dodecyl betaine are added each time;
(3) purifying the filtrate: the filtrate obtained in the step (2) is processed according to the formula of n (Ca)2+):n(SO42-) Adding a sulfuric acid solution with the mass concentration of 85% at the ratio of 1:1, carrying out calcium removal reaction at 50 ℃ under the stirring condition of 500 revolutions per minute, and carrying out solid-liquid separation after 2 hours of reaction; adding ammonia water into the obtained filtrate to slowly adjust the pH value to 3.5 to generate white precipitate, continuously adding ammonia water into the filtrate after filtration and separation to adjust the pH value to 6.5 to generate white precipitate, adding ammonia water into the filtrate after filtration and separation again to adjust the pH value to 9 to generate white precipitate, and filtering and separating to obtain filter residue and purified filtrate;
(4) preparing an NPK compound fertilizer: evaporating, concentrating and granulating the purified filtrate obtained in the step (3) at 100 ℃ to prepare 103.4g of NPK compound fertilizer, and detecting N, P in the compound fertilizer2O5、K2The O and Cl contents were 25.1%, 42.1%, 5.8% and 16.4%, respectively.
Comparative example 3
(1) Acid leaching: mixing 60g of ground phosphate tailings, 20g of potassium feldspar, 480mL of hydrochloric acid solution (the mass concentration is 25 percent) and 0.016g of surfactant (the mass ratio of sodium dodecyl benzene sulfonate to dodecyl betaine is 1: 0.3), carrying out leaching reaction at 30 ℃, and carrying out solid-liquid separation after 2 hours to obtain leaching residues and leaching liquid;
(2) leaching liquor is circularly leached: supplementing acid to the leachate obtained in the step (1), then recycling the next batch of minerals, and repeating the step (1) for 4 times to separate solid from liquid to obtain filter residue and P, K-enriched filtrate; in the process, 80g of phosphorus tailings, 30g of potassium feldspar, 48mL of hydrochloric acid solution (the mass concentration is 25%) and 0.0024g of surfactant (the mass ratio of sodium dodecyl benzene sulfonate to dodecyl betaine is 1: 0.3) are added each time;
(3) purifying the filtrate: the filtrate obtained in the step (2) is processed according to the formula of n (Ca)2+):n(SO42-) Adding a sulfuric acid solution with the mass concentration of 85% at the ratio of 1:1, carrying out calcium removal reaction at 50 ℃ under the stirring condition of 500 revolutions per minute, and carrying out solid-liquid separation after 2 hours of reaction; adding ammonia water into the obtained filtrate to slowly adjust the pH value to 3.5 to generate white precipitate, continuously adding ammonia water into the filtrate after filtration and separation to adjust the pH value to 6.5 to generate white precipitate, adding ammonia water into the filtrate after filtration and separation again to adjust the pH value to 9 to generate white precipitate, and filtering and separating to obtain filter residue and purified filtrate;
(4) preparing an NPK compound fertilizer: evaporating, concentrating and granulating the purified filtrate obtained in the step (3) at 100 ℃ to prepare 205.3g of NPK compound fertilizer, and detecting N, P in the compound fertilizer2O5、K2The O and Cl contents were 24.2%, 28.5%, 7.4% and 18.4%, respectively.
Comparative example 4
(1) Acid leaching: mixing 60g of ground phosphate tailings, 20g of potassium feldspar, 240mL of hydrochloric acid solution (the mass concentration is 25 percent) and 0.016g of surfactant (the mass ratio of sodium dodecyl benzene sulfonate to dodecyl betaine is 1: 0.3), carrying out leaching reaction at 30 ℃, and carrying out solid-liquid separation after 2 hours to obtain leaching residues and leaching liquid;
(2) leaching liquor is circularly leached: supplementing acid to the leachate obtained in the step (1), then recycling the next batch of minerals, and repeating the step (1) for 4 times to separate solid from liquid to obtain filter residue and P, K-enriched filtrate; in the process, 20g of phosphorus tailings, 90g of potassium feldspar, 48mL of hydrochloric acid solution (the mass concentration is 25%) and 0.0024g of surfactant (the mass ratio of sodium dodecyl benzene sulfonate to dodecyl betaine is 1: 0.3) are supplemented each time;
(3) purifying the filtrate: will step withThe filtrate obtained in the step (2) is prepared according to the formula of n (Ca)2+):n(SO42-) Adding a sulfuric acid solution with the mass concentration of 85% at the ratio of 1:1, carrying out calcium removal reaction at 50 ℃ under the stirring condition of 500 revolutions per minute, and carrying out solid-liquid separation after 2 hours of reaction; adding ammonia water into the obtained filtrate to slowly adjust the pH value to 3.5 to generate white precipitate, continuously adding ammonia water into the filtrate after filtration and separation to adjust the pH value to 6.5 to generate white precipitate, adding ammonia water into the filtrate after filtration and separation again to adjust the pH value to 9 to generate white precipitate, and filtering and separating to obtain filter residue and purified filtrate;
(4) preparing an NPK compound fertilizer: evaporating, concentrating and granulating the purified filtrate obtained in the step (3) at 100 ℃ to prepare 183.1g of NPK compound fertilizer, and detecting N, P in the compound fertilizer2O5、K2The O and Cl contents were 18.4%, 12.1%, 12.2% and 23.2%, respectively.
The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are included in the scope of the present invention.

Claims (9)

1. A method for preparing NPK compound fertilizer by using phosphate tailings and potassium feldspar is characterized by comprising the following steps:
(1) acid leaching: mixing the ground phosphate tailings and potash feldspar with hydrochloric acid and a surfactant, blending, carrying out leaching reaction at 20-40 ℃, and carrying out solid-liquid separation after 1-3 hours to obtain leaching slag and leaching liquid; wherein the surfactant is sodium dodecyl benzene sulfonate and dodecyl betaine according to the weight ratio of 1: (0.2-0.4) in mass ratio;
(2) leaching liquor is circularly leached: adding hydrochloric acid and a surfactant into the leachate obtained in the step (1), then recycling the leachate to treat the next batch of minerals, and after repeating the step (1) for a plurality of times, carrying out solid-liquid separation to obtain filter residues and a filtrate enriched with phosphorus and potassium;
(3) purifying the filtrate: sequentially removing calcium from the filtrate obtained in the step (2) by using sulfuric acid, and neutralizing by using ammonia water to remove aluminum, iron and magnesium to obtain refined filtrate;
(4) preparing an NPK compound fertilizer: and (4) evaporating, concentrating and granulating the filtrate obtained in the step (3) to prepare the low-chlorine high-concentration NPK compound fertilizer.
2. The method for preparing NPK compound fertilizer by using phosphorus tailings and potassium feldspar according to claim 1, wherein P in the phosphorus tailings selected in the step (1) is P2O55-20 wt% of CaO, 30-50 wt% of CaO and 0.5-5 wt% of F; k in selected potassium feldspar2The content of O is 7-15 wt%; the mass ratio of the phosphate tailings to the potassium feldspar is (2-5): 1.
3. the method for preparing the NPK compound fertilizer by using the phosphate tailings and the potassium feldspar according to claim 1, wherein the concentration of the hydrochloric acid selected in the step (1) is 20-30%, and the dosage ratio of the phosphate tailings, the potassium feldspar and the hydrochloric acid is 1 g: (2-4) ml.
4. The method for preparing the NPK compound fertilizer by using the phosphate tailings and the potassium feldspar according to claim 1, wherein the mass ratio of the phosphate tailings, the potassium feldspar and the surfactant in the step (1) is 1000: (0.1-0.3).
5. The method for preparing the NPK compound fertilizer by using the phosphate tailings and the potassium feldspar according to claim 1, wherein the mass ratio of the sodium dodecyl benzene sulfonate to the dodecyl betaine in the surfactant is 1: 0.3.
6. The method for preparing the NPK compound fertilizer by using the phosphate tailings and the potassium feldspar according to claim 1, wherein the frequency of repeating the step (1) after adding the hydrochloric acid and the surfactant in the step (2) and recycling the next batch of minerals is 2-4.
7. The method for preparing the NPK compound fertilizer by using the phosphorus tailings and the potassium feldspar according to claim 1, wherein in the step (2), the mass ratio of the phosphorus tailings to the potassium feldspar in the next batch of processed minerals is (1-2.5): 1, the adding amount of each time of the mixture is 1.3-1.7 times of the total amount of the ore in the step (1); the hydrochloric acid replenished each time accounts for 10-20% of the adding amount of the hydrochloric acid in the step (1); and (3) the surfactant supplemented in the step (2) accounts for 10-20% of the adding amount of the surfactant in the step (1).
8. The method for preparing NPK compound fertilizer by using phosphate tailings and potassium feldspar according to claim 1, wherein the calcium removal by sulfuric acid in the step (3) is specifically as follows: according to n (Ca)2+):n(SO4 2-) 1: (0.8-1.2) adding a sulfuric acid solution with the mass concentration of 50-98%, and reacting at 30-90 ℃ for 0.5-3 h.
9. The method for preparing the NPK compound fertilizer by using the phosphate tailings and the potassium feldspar according to claim 1, wherein the step (3) of removing aluminum, iron and magnesium in ammonia water specifically comprises the following steps: the pH value is adjusted to 3.5 by using an ammonia water solution to precipitate for iron removal, then the pH value is adjusted to 6.5 to precipitate for aluminum removal, and finally the pH value is adjusted to 9 to precipitate for magnesium removal.
CN202110048932.3A 2021-01-14 2021-01-14 Method for preparing NPK compound fertilizer by using phosphate tailings and potassium feldspar Active CN112898073B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202110048932.3A CN112898073B (en) 2021-01-14 2021-01-14 Method for preparing NPK compound fertilizer by using phosphate tailings and potassium feldspar

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202110048932.3A CN112898073B (en) 2021-01-14 2021-01-14 Method for preparing NPK compound fertilizer by using phosphate tailings and potassium feldspar

Publications (2)

Publication Number Publication Date
CN112898073A true CN112898073A (en) 2021-06-04
CN112898073B CN112898073B (en) 2023-01-20

Family

ID=76113095

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202110048932.3A Active CN112898073B (en) 2021-01-14 2021-01-14 Method for preparing NPK compound fertilizer by using phosphate tailings and potassium feldspar

Country Status (1)

Country Link
CN (1) CN112898073B (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114634355A (en) * 2022-03-11 2022-06-17 苏州大学 Treatment method for recycling ferrous lepidolite leaching residues
CN114634319A (en) * 2022-03-11 2022-06-17 苏州大学 Treatment method for recycling calcium-containing lepidolite leaching residues

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN100999423A (en) * 2006-12-31 2007-07-18 合肥工业大学 Method of preparing nitrogen phosphorus potassium complex fertilizer using potash feldspar
CN104744175A (en) * 2015-04-03 2015-07-01 武汉工程大学 Method for producing nitrogen-phosphorus-potassium mixed fertilizer by utilizing phosphorus-potassium associated ore
CN105367176A (en) * 2015-12-02 2016-03-02 武汉工程大学 Multi-element comprehensive utilization process for phosphorus-potassium associated ore
CN106507806B (en) * 1999-05-25 2016-10-05 核工业北京化工冶金研究院 The method for improving ore leaching efficiency
CN106278391A (en) * 2016-07-22 2017-01-04 武汉工程大学 A kind of hydrochloric acid that directly utilizes decomposes phosphorus potassium associated minerals and the method for phosphorus ore composite ore under cryogenic
CN112725638A (en) * 2021-01-21 2021-04-30 瓮福（集团）有限责任公司 Method for strengthening leaching of potassium in potassium feldspar by using surfactant
CN113184855A (en) * 2021-04-21 2021-07-30 武汉工程大学 Resource comprehensive utilization method of phosphogypsum and potassium feldspar

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106507806B (en) * 1999-05-25 2016-10-05 核工业北京化工冶金研究院 The method for improving ore leaching efficiency
CN100999423A (en) * 2006-12-31 2007-07-18 合肥工业大学 Method of preparing nitrogen phosphorus potassium complex fertilizer using potash feldspar
CN104744175A (en) * 2015-04-03 2015-07-01 武汉工程大学 Method for producing nitrogen-phosphorus-potassium mixed fertilizer by utilizing phosphorus-potassium associated ore
CN105367176A (en) * 2015-12-02 2016-03-02 武汉工程大学 Multi-element comprehensive utilization process for phosphorus-potassium associated ore
CN106278391A (en) * 2016-07-22 2017-01-04 武汉工程大学 A kind of hydrochloric acid that directly utilizes decomposes phosphorus potassium associated minerals and the method for phosphorus ore composite ore under cryogenic
CN112725638A (en) * 2021-01-21 2021-04-30 瓮福（集团）有限责任公司 Method for strengthening leaching of potassium in potassium feldspar by using surfactant
CN113184855A (en) * 2021-04-21 2021-07-30 武汉工程大学 Resource comprehensive utilization method of phosphogypsum and potassium feldspar

Non-Patent Citations (4)

* Cited by examiner, † Cited by third party
Title
刘存成等: "表面活性剂对磷钾伴生矿中钾浸出的影响", 《武汉工程大学学报》 *
刘荃等: "钾长石与磷矿共酸浸制NPK复合肥研究", 《安徽化工》 *
杜学兰等: "表面活性剂对磷钾伴生矿提钾过程的影响", 《有色金属(冶炼部分)》 *
齐越超等: "含钾磷矿综合利用研究现状", 《材料研究与应用》 *

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114634355A (en) * 2022-03-11 2022-06-17 苏州大学 Treatment method for recycling ferrous lepidolite leaching residues
CN114634319A (en) * 2022-03-11 2022-06-17 苏州大学 Treatment method for recycling calcium-containing lepidolite leaching residues

Also Published As

Publication number Publication date
CN112898073B (en) 2023-01-20

Similar Documents

Publication Publication Date Title
CN111039310B (en) Method for preparing sodium bicarbonate and co-producing ammonium sulfate from sodium sulfate
CN112898073B (en) Method for preparing NPK compound fertilizer by using phosphate tailings and potassium feldspar
CN104477943B (en) A kind of method of preparing potassium sulfate
CN105367176B (en) A kind of multielement composite of phosphorus potassium associated minerals utilizes technique
CN108752059B (en) Method for producing forest silicon-calcium-manganese composite mineral fertilizer by using manganese slag
CN114105171A (en) Method for recycling and comprehensively utilizing lepidolite and lithium hydroxide prepared by method
CN100999423A (en) Method of preparing nitrogen phosphorus potassium complex fertilizer using potash feldspar
CN107814370B (en) Circulating environment-friendly process method for preparing phosphate concentrate, product and application thereof
CN113735081A (en) Method for pretreating phosphorite
CN111039305B (en) Method for preparing sodium bicarbonate and ammonium sulfate by sodium sulfate in short process
CN104774125B (en) A kind of method of the rich nitrogen sulfate fertilizer of utilization ardealite production and recovering rare earth
CN102126742A (en) Method for producing chloride-based compound fertilizer and co-producing gypsum through decomposing phosphorite with hydrochloric acid
CN104311190A (en) Method for producing high concentration chlorine-based composite fertilizer by partially decalcifying hydrochloric acid decomposed phosphorite
CN104313346B (en) Process for recovering aluminum, potassium and gallium by quickly reducing and desulfurizing alunite at high temperature
CN105648239A (en) Process for leaching dissoluble potassium from polyhalite
CN106564926B (en) A kind of method that hydrochloric acid decomposition phosphorus tailing prepares calcium sulfate and high magnesium compound fertilizer
CN110217769B (en) Method for producing calcium ammonium nitrate byproduct feed-grade DCP
CN112725638A (en) Method for strengthening leaching of potassium in potassium feldspar by using surfactant
CN112758937B (en) Method for preparing potassium fluosilicate and NPK compound fertilizer from associated phosphate-potassium ore
CN106986723A (en) A kind of waste residue of Phosphate Fertilizer Nitrate with Frozen Method technique prepares composite fertilizer
CN113184855A (en) Resource comprehensive utilization method of phosphogypsum and potassium feldspar
CN111072054A (en) Preparation of high-purity gypsum powder and byproduct NH from phosphogypsum4Cl process
CN113401928B (en) Method for removing calcium from fly ash and/or coal gangue by acid washing with ultrasonic waves
CN112553470B (en) Method for recovering aluminum hydroxide powder by using titanium dioxide waste acid and secondary aluminum ash
CN114314540A (en) Method for producing magnesium hydrogen phosphate by using phosphate tailings

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
CB02 Change of applicant information
CB02 Change of applicant information

Address after: 441021 No.1 Tianshun Avenue, Xiangcheng Economic Development Zone, Xiangyang City, Hubei Province

Applicant after: Xiangyang Zedong Chemical Group Co.,Ltd.

Applicant after: WUHAN INSTITUTE OF TECHNOLOGY

Address before: 441021 No.1 Tianshun Avenue, Xiangcheng Economic Development Zone, Xiangyang City, Hubei Province

Applicant before: XIANGYANG ZEDONG CHEMICAL GROUP Co.,Ltd.

Applicant before: WUHAN INSTITUTE OF TECHNOLOGY

GR01 Patent grant
GR01 Patent grant