WO2013075615A1

WO2013075615A1 - Method for joint production of potassium-rich solution by mineralizing co2

Info

Publication number: WO2013075615A1
Application number: PCT/CN2012/084914
Authority: WO
Inventors: 谢和平; 王昱飞; 刘建锋
Original assignee: 四川大学
Priority date: 2011-11-25
Filing date: 2012-11-20
Publication date: 2013-05-30
Also published as: CN102491795A; CN102491795B

Abstract

Disclosed is a method for the joint production of a potassium-rich solution by mineralizing CO₂, the method mainly comprising the following process steps: crushing ores rich in potassium feldspar into powder; placing the crushed ore powder into a reactor, adding a calcium chloride solution, and feeding in carbon dioxide gas; carrying out the mineralization reaction under the conditions of a temperature of 150°C-350°C and a partial pressure of carbon dioxide of not less than 1.0 MPa, mineralizing CO₂ to generate calcium carbonate, and the potassium feldspar dissolving to generate a solution rich in potassium ions; and feeding the obtained slurry after fully reacting to a separating device for solid-liquid separation, the obtained solid phase being a solid containing the mineralization product of calcium carbonate and the liquid phase being a solution rich in potassium ions. The present invention jointly produces a potassium-rich solution during CO₂mineralization, breaks through the bottleneck of having low additional values of CO₂mineralization product and CO₂mineralization technology being difficult to implement in industry in the CO₂mineralization methods in the prior art, helps to solve the problem of CO₂ emission reduction, and at the same time provides an adequate potassium source for potash fertilizer production.

Description

TECHNICAL FIELD The present invention relates to a method for reducing CO ₂ by mineralization, and particularly relates to mineralizing C0 ₂ using potassium feldspar-rich ore and calcium chloride solution, and simultaneously producing rich The method of potassium solution. BACKGROUND OF THE INVENTION Carbon dioxide (C0 ₂ ), as a greenhouse gas, is a major cause of global warming. Due to the rapid development of industry, a large amount of energy is consumed, and carbon dioxide emissions are also increasing. According to a report released by the International Energy Agency (IEA) in 2009, global carbon dioxide emissions have reached 29 billion tons in 2007, and China's carbon dioxide emissions. It is 6 billion tons, accounting for 21% of global emissions, and has surpassed the United States to become the world's largest energy-related carbon dioxide emitter. In recent years, extreme weather such as snowstorms, heat, and heavy rain have occurred frequently. The world is suffering from the huge disaster caused by the greenhouse effect. In the face of such a severe environmental situation, how to reduce carbon dioxide emissions and more effectively alleviate the greenhouse effect has become Important issues to be solved and the problems faced by countries around the world. At present, for the treatment of large-scale carbon dioxide, there are mainly three methods: geological storage, marine storage and C0 ₂ mineralization. C0 ₂ mineralization refers to a process in which a basic compound and an alkaline earth oxide are reacted with CO ₂ to form a stable compound to fix carbon dioxide. [0 _{2 The} mineralized product carbonate compound can exist stably in nature for thousands of years, and is a method for stably and safely fixing C0 ₂ . At present, the raw materials selected for the C0 ₂ mineralization reaction at home and abroad are mainly magnesium silicate (Mg ₂ Si0 ₄ ) and calcium silicate (CaSi0 ₃ ) chemicals, which are stored in nature in large quantities, alkali. Sex is stronger than other metal chemicals. However, because the existing C0 ₂ mineralization process does not have high value-added products, the economics of the C0 ₂ mineralization process is low. Therefore, how to use the C0 ₂ mineralization process to simultaneously produce high value-added chemical products, so that C0 ₂ Mineralization and storage make economically viable, which is the bottleneck of C0 ₂ mineralization to achieve industrialization. China is a country that lacks potassium. The world's potash production raw materials are mainly derived from water-soluble potassium salt deposits, 96% of which are distributed in Canada, France, Germany, the United States and other countries and regions, while most of the developing countries and regions have scarce water-soluble potassium ore resources. China's water-soluble potassium ore resources are rare, accounting for only 0.29% of the world's resources. Non-water-soluble potassium ore resources are abundant, totaling more than 2x l0 ^1Q t, mainly potassium feldspar and mica. There have been many experimental developments in China. Potash feldspar produces potash, but it is not industrially produced due to high energy consumption. Despite the development of salt lake resources such as Qinghai Lake and Qaidam in China, the existing potash production has reached 4 million tons, and the annual consumption in China is 7 million tons (calculated as K ₂ 0). Therefore, it needs to be imported every year. A lot of potash. At present, there are 60 sources of potassium feldspar in China, and its reserves are about 7.914 billion yuan. The average amount of potassium oxide is about 920 million. If it is effectively developed and utilized, it can meet the demand of China's potash for 100 years. SUMMARY OF THE INVENTION In view of the current situation of CO ₂ mineralization technology and lack of potash production resources in China, the purpose of the present invention is to provide a new CO ₂ mineralization method for co-production of potassium-rich solution in the process of [0 ₂ mineralization, in order to break through the existing technology exists due to the low value-added product C0 ₂ mineralization, mineralization people to bottlenecks C0 ₂ emission reduction technology C0 ₂ mineralization are not enthusiastic about the cause of industrialization difficult to implement, while helping to overcome the shortage of China's potash fertilizer production resources problem. The above object of the present invention can be achieved by a CO ₂ mineralization method for co-production of a potassium-rich solution, which is defined by the following technical solution, to solve the technical problem to be solved. In order to achieve the above object, according to an aspect of the present invention, a CO ₂ mineralization method for co-producing a potassium-rich solution is provided. The method mainly comprises the following steps: (1) pulverizing the ore rich in potassium feldspar into a powder; (2) placing the pulverized ore powder in a reactor, adding a calcium chloride solution, and introducing carbon dioxide gas to Mineralization reaction at 150~350 °C, carbon dioxide partial pressure not lower than 1.0 MPa, C0 ₂ mineralization to form calcium carbonate, potassium feldspar dissolved, and a potassium ion-rich solution is formed; (3) Step (2) The slurry obtained by the sufficient reaction is sent to a separation device for solid-liquid separation, and the obtained solid phase is a solid containing a mineralized product of calcium carbonate, and the liquid phase is a potassium-rich solution rich in potassium ions. Further, the ore powder is heated and activated before being placed in the reactor for mineralization reaction, and the activation temperature is

400-800 ° C, preferably, the activation temperature is 500 to 700 ° C. Further, the mineralization reaction is carried out under agitation. Further, the stirring rate is from 100 r/min to 1500 r/min. Further, the concentration of the calcium chloride solution is 0.1 mol/L to 5 mol/L, and the ratio of the ore powder to the calcium chloride solution is 10 g to 500 g of ore powder/1 liter of calcium chloride solution, preferably, ore powder and The calcium chloride solution is used in an amount of 50 g to 150 g of ore powder per 1 liter of calcium chloride solution. Further, the temperature of the mineralization reaction is 200 to 300 ° C, and the partial pressure of carbon dioxide is 1.0 MPa to 35 MPa. Further, the ore rich in potassium feldspar is an ore having a potassium content of not less than 5%, and the mineral component thereof contains at least one of feldspar, perlite and micro plagioclase. Further, the ore rich in potassium feldspar is pulverized to a powder having a particle diameter of not more than 20 mesh. According to another aspect of the invention, a CO ₂ mineralization process for co-producing a potassium-rich solution is provided. The method comprises the following steps: (1) pulverizing the ore rich in potassium feldspar into ore powder; (2) preparing the ore powder and the calcium chloride solution After mixing, the resulting mixture is subjected to a mineralization reaction in an atmosphere of carbon dioxide to form a solution of calcium carbonate and potassium ions. Further, the method further comprises: (3) performing solid-liquid separation of the calcium carbonate and the potassium ion-rich solution. Further, the temperature of the mineralization reaction is 150 to 350 ° C, preferably, the temperature of the mineralization reaction is 200 to 300 ° C _; the atmosphere of carbon dioxide is a partial pressure of carbon dioxide of not less than 1.0 MPa, preferably, the atmosphere of carbon dioxide is The partial pressure of carbon dioxide is 1.0 MPa~35 MPa. Further, the step (1) and the step (2) further comprise: heating and activating the ore powder in a nitrogen atmosphere, the temperature of the heating activation is 400 to 800 ° C, preferably, the heating activation temperature is 500 to 700 °C. The CO ₂ mineralization method for co-production of a potassium-rich solution provided by the present invention is a potassium-rich rock containing potassium feldspar as a main mineral component, and reacts with C0 ₂ in a calcium chloride solution to form mineralization. At the same time, the product calcium carbonate obtains a new process of potassium-rich solution which is rich in potassium ions and can be used for preparing potassium fertilizer. The CO ₂ mineralization method of the invention makes the CO _{2 change} from a gaseous state to a stable calcium carbonate solid, and the calcium carbonate can exist stably in nature for thousands of years without harmful effects on the environment, and provides a carbon dioxide mineralization treatment. A new method. The invention realizes the potassium-rich solution which is rich in potassium ions and can be used for preparing potassium fertilizer while completing the [0 ₂ mineralization, and realizes the extraction of potassium element from the water-insoluble potassium ore. Potassium is an essential element for crop growth, but China's potash production resources are scarce. The water-soluble potassium salt that can be directly used to produce potash fertilizer is very small. As a result, China's potash production is far from meeting the needs of agricultural production, and a large number of imports are needed to fill the supply gap. However, China's water-insoluble potassium ore is extremely rich, so the disclosure and implementation of the present invention provides a new method of C0 ₂ mineralization, which can break through the existing C0 ₂ mineralization method due to the added value of C0 ₂ mineralization products. Low, people do not have high enthusiasm for C0 ₂ mineralization, C0 ₂ mineralization technology is difficult to implement industrial bottlenecks, help solve global C0 ₂ emission reduction problems, and provide sufficient potassium resources for potash production to solve potash production. The shortage of resources. BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings are intended to provide a further understanding of the invention In the drawings: Figure 1 is a schematic block diagram of a process flow of one embodiment of the present invention. Figure 2 is a schematic block diagram of a process flow of another embodiment of the present invention. The objects indicated by the reference numerals in the above figures are: 1--crushing device; 2-mineralization reactor; 3-solid-liquid separation device; 4-activation heating device. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The CO ₂ mineralization method for co-production of a potassium-rich solution proposed by the present invention mainly includes the following process steps:

(1) pulverizing the ore rich in potassium feldspar into a powder;

(2) placing the ore powder after the pulverization in the reactor, adding a calcium chloride solution, introducing carbon dioxide gas, and performing a mineralization reaction at 150 to 350 ° C and a partial pressure of carbon dioxide of not less than 1.0 MPa. C0 ₂ mineralization produces calcium carbonate, and potassium feldspar dissolves to form a solution rich in potassium ions;

(3) Step (2) The slurry obtained by the sufficient reaction is sent to a separation device for solid-liquid separation, and the obtained solid phase is a solid containing a mineralized product of calcium carbonate, and the liquid phase is a potassium-rich solution rich in potassium ions. The prepared potassium-rich potassium-rich solution can be used as a raw material to prepare potassium fertilizer through further processing to meet the needs of agricultural production for potassium fertilizer. In order to better achieve the object of the present invention, the present invention can further take the following technical measures based on the above technical solutions. The following technical measures can be taken individually or in combination, or even taken together. In order to increase the rate of mineralization reaction, it is preferred to heat and activate the pulverized ore powder before it is placed in the reactor for mineralization. The heating activation temperature can be generally in the range of 400 to 800 ° C, and the preferred activation temperature is 500. ~70 (TC. In order to further increase the mineralization reaction rate, the mineralization reaction is preferably carried out under stirring conditions. The stirring rate is preferably in the range of 100 r/min to 1500 r/min. The mineralization reaction temperature is preferably controlled at 200~300 °C, and the partial pressure of carbon dioxide (C0 ₂ ) gas is preferably controlled at 1.0 MPa~35 MPa. That is, the gas introduced into the reactor regardless of the pressure and the mass concentration of C0 ₂ The partial pressure of C0 ₂ gas is only in the range. In the above technical solution, the amount of potassium feldspar-rich ore, C0 ₂ and calcium chloride solution components is not very strict, some kind The addition amount of the components is too large to obtain a reaction. However, it is preferable that the amount of each component is added within a certain range of the stoichiometric amount of the C0 ₂ mineralization reaction. The specific operation is to control the crushed ore powder and the calcium chloride solution. Ratio of use, The range of the ratio is generally one liter of calcium chloride solution with 10g ~ 500g ore powder, that is, 10g ~ 500g ore powder / 1 liter of calcium chloride solution, preferably in the range of 50g ~ 150g ore powder / 1 liter of calcium chloride solution. The concentration of calcium chloride in the calcium solution is 0.1 mol/L to 5 mol/L. In the above technical solution, the ore rich in potassium feldspar is an ore having a potassium (K ₂ 0) mass content of not less than 5%, and the mineral component thereof comprises at least at least of feldspar, permeable feldspar and micro plagioclase. One. The pulverized ore is a powder having a particle diameter of not more than 20 mesh. In the above technical solution, the length of the mineralization reaction time depends on the particle size of the ore after pulverization, whether it is activated, the temperature of the mineralization reaction, whether the mineralization reaction process is stirred, the strength of the stirring, and the like, generally 10 min~ 600 min. The present invention is described below in conjunction with the process flow diagram, and the present invention will be further described in detail by way of examples. It is to be understood that the following examples are only used to further illustrate the present invention and are not to be construed as limiting the scope of the present invention. Those skilled in the art will make some non-essential improvements and adjustments to the present invention. It is very easy to carry out the specific implementation, and therefore such improvements and adjustments should still fall within the scope of protection of the present invention. In the following examples, the percentages of the components involved are percentages by mass unless otherwise specified. Embodiment 1 The process flow of this embodiment is as shown in FIG. The feldspar-rich ore is crushed and ball milled to a powder with a particle size of less than 200 mesh. 50 g of the crushed ore powder is added to a 2000 ml batch high pressure reactor, and 1000 ml of calcium chloride solution is added. The concentration of the calcium chloride solution is 0.5 mol/L, seal the reactor, raise the temperature to 180 ° C, pass C0 ₂ until the pressure in the reactor rises to 5 MPa, start the stirrer, adjust the stirring rate to 500 r / min, the reaction is about 300 min , stop the reaction. After the autoclave was cooled to normal temperature and discharged to atmospheric pressure, the reaction vessel was opened, and the product was filtered to obtain a solid containing a CO ₂ mineralized product calcium carbonate, and a liquid phase solution rich in potassium ions. In this process, the extraction rate of potassium is up to 6%. Embodiment 2 The process flow of this embodiment is also shown in FIG. The feldspar-rich ore is ball milled to a powder with a particle size of less than 100 mesh. 100 g of the crushed ore powder is added to a 2000 ml batch high pressure reactor, and 1000 ml of calcium chloride solution is added. The concentration of the calcium chloride solution is 4 mol/L, seal the reactor, raise the temperature to about 300 °C, pass C0 ₂ until the pressure in the reactor rises to 3 MPa, start the stirrer, adjust the stirring rate to 800 r / min, the reaction is about 120 Min, stop the reaction. After the autoclave was cooled to normal temperature and discharged to atmospheric pressure, the reaction vessel was opened, and the product was filtered to obtain a solid containing a CO ₂ mineralized product calcium carbonate, and a liquid phase solution rich in potassium ions. In this process, the extraction rate of potassium is up to 9%. Implementation example 3 The process flow of this embodiment is as shown in FIG. 2. The ore-rich feldspar-rich ore is ball milled to a powder with a particle size of less than 200 mesh. 50 g of the pulverized ore powder powder is taken, activated at 500 ° C for about 5 hours under nitrogen protection, and then placed in a 2000 ml batch high pressure. In the reaction kettle, add 1000 ml of calcium chloride solution, the concentration of the calcium chloride solution is 2 mol/L, seal the reaction vessel, raise the temperature to about 200 ° C, and pass C0 ₂ until the pressure in the reactor rises. At 10 MPa, start the stirrer, adjust the stirring rate to 500 r/min, and react for 180 min to stop the reaction. After the autoclave was cooled to normal temperature and discharged to atmospheric pressure, the reaction vessel was opened, and the product was filtered to obtain a solid containing a CO ₂ mineralized product calcium carbonate, and a liquid phase solution rich in potassium ions. In this process, the extraction rate of potassium is up to 11%.

Embodiment 4 The process flow of this embodiment is also shown in Fig. 2. An ore-rich ore crushed ball milled to a particle size smaller than

200 mesh powder, measure 100 g of crushed ore powder, activate at 700 ° C for about 3 hours under nitrogen protection, then place in 2000 ml batch high pressure reactor, add 1000 ml of calcium chloride solution, chlorine The concentration of the calcium solution is 1 mol/L, the reactor is sealed, the temperature is raised to about 250 ° C, and a mixture of C0 ₂ and nitrogen (in which the volume of carbon dioxide accounts for 60%) is passed until the pressure in the reactor rises to 25 MPa, start the stirrer, adjust the stirring rate to 1000 r / min, react for 120 min, stop the reaction. After the autoclave was cooled to normal temperature and discharged to atmospheric pressure, the reaction vessel was opened, and the product was filtered to obtain a solid containing a CO ₂ mineralized product calcium carbonate, and a liquid phase solution rich in potassium ions. In this process, the potassium extraction rate can reach 13%. The above is only the preferred embodiment of the present invention, and is not intended to limit the present invention, and various modifications and changes can be made to the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and scope of the present invention are intended to be included within the scope of the present invention.

Claims

Claim

A CO ₂ mineralization method for co-production of a potassium-rich solution, characterized in that it mainly comprises the following process steps:

(1) pulverizing the ore rich in potassium feldspar into a powder;

(2) placing the pulverized ore powder in a reactor, adding a calcium chloride solution, introducing carbon dioxide gas, and performing a mineralization reaction at a temperature of 150 to 350 ° C and a partial pressure of carbon dioxide of not less than 1.0 MPa, C0 ₂ mineralization produces calcium carbonate, potassium feldspar dissolves, and a solution rich in potassium ions is formed;

(3) Step (2) The slurry obtained by the sufficient reaction is sent to a separation apparatus for solid-liquid separation, and the obtained solid phase is a solid containing a mineralized product of calcium carbonate, and the liquid phase is a potassium-rich solution rich in potassium ions.

2. The CO ₂ mineralization method for co-production of a potassium-rich solution according to claim 1, wherein the ore powder is heated and activated before being placed in the reactor for the mineralization reaction, and the activation temperature is 400 to 800°. C. Preferably, the activation temperature is 500 to 700 °C.

3. The CO ₂ mineralization method for co-production of a potassium-enriched solution according to claim 1, wherein the mineralization reaction is carried out under agitation.

4. The CO ₂ mineralization method for co-production of a potassium-rich solution according to claim 3, wherein the stirring rate is from 100 r/min to 1500 r/min.

The CO ₂ mineralization method for co-production of a potassium-rich solution according to any one of claims 1 to 4, characterized in that the concentration of the calcium chloride solution is from 0.1 mol/L to 5 mol/L, and the ore powder and The calcium chloride solution is used in an amount of from 10 g to 500 g of ore powder per 1 liter of calcium chloride solution. Preferably, the ratio of the ore powder to the calcium chloride solution is from 50 g to 150 g of ore powder per 1 liter of calcium chloride solution.

The CO ₂ mineralization method for co-production of a potassium-rich solution according to any one of claims 1 to 4, wherein the temperature of the mineralization reaction is 200 to 300 ° C, and the partial pressure of carbon dioxide is 1.0 MPa to 35 MPa.

The CO ₂ mineralization method for co-production of a potassium-rich solution according to any one of claims 1 to 4, wherein the ore-rich feldspar-rich ore is an ore having a potassium content of not less than 5%. The mineral component comprises at least one of feldspar, perlite and micro plagioclase.

The CO ₂ mineralization method for co-production of a potassium-rich solution according to claim 7, wherein the potassium feldspar-rich ore is pulverized to a powder having a particle diameter of not more than 20 mesh.

9. A CO ₂ mineralization method for co-production of a potassium-rich solution, comprising the steps of: (1) crushing ore rich in potassium feldspar into ore powder;

(2) The ore powder is mixed with a calcium chloride solution, and the resulting mixture is subjected to a mineralization reaction in a carbon dioxide atmosphere to form a solution of calcium carbonate and potassium ions.

10. C0 ₂ mineralization method of claim 9, characterized in that, further comprising:

(3) Solid-liquid separation of calcium carbonate and a solution rich in potassium ions.

The CO ₂ mineralization method according to claim 9, wherein the temperature of the mineralization reaction is

150-350 ° C, preferably, the temperature of the mineralization reaction is 200-300 ° C _; the atmosphere of carbon dioxide is a partial pressure of carbon dioxide of not less than 1.0 MPa, preferably, the atmosphere of the carbon dioxide is a partial pressure of carbon dioxide 1.0 MPa~35 MPa.

12. The C0 ₂ mineralization method according to claim 9, wherein the step (1) and the step (2) further comprise:

The ore powder is heated and activated in a nitrogen atmosphere, and the heating activation temperature is 400 to 800 ° C. Preferably, the heating activation temperature is 500 to 700 ° C.

The CO ₂ mineralization method according to claim 9, wherein the mineralization reaction is performed under stirring conditions, and preferably, the stirring rate is 100 r/min to 1500 r/ Min.

The C0 ₂ mineralization method according to any one of claims 9 to 13, wherein the calcium chloride solution has a concentration of 0.1 mol/L to 5 mol/L, and the ore powder and chlorine The calcium solution is used in an amount of from 10 g to 500 g of ore powder per 1 liter of calcium chloride solution. Preferably, the ratio of the ore powder to the calcium chloride solution is from 50 g to 150 g of ore powder per 1 liter of calcium chloride solution.

The method for mineralizing C0 ₂ according to claim 9, wherein the ore rich in potassium feldspar is an ore having a potassium content of not less than 5%, and the mineral component comprises feldspar and longitude. At least one of stone and micro plagioclase.

16. The CO ₂ mineralization method according to claim 9, wherein the potassium feldspar-rich ore is pulverized to a powder having a particle diameter of not more than 20 mesh.