A device and method for co-producing yellow phosphorus and synthesis gas by reducing phosphate ore by pressurized gasification of phosphorus coal

Abstract

The present invention discloses a device for co-producing yellow phosphorus and synthesis gas by reducing phosphate ore by pressurized gasification of phosphorus coal, characterized in that it comprises a grinding and balling unit, an air separation unit, a phosphorus coal gasification and reduction unit, and a separation and purification unit; the grinding and balling unit is used to grind part of the raw materials into powder and prepare phosphorus pellets; the air separation unit is used to separate air components and prepare oxygen; the phosphorus coal gasification and reduction unit realizes the gasification and reduction reaction of each material in the device to obtain phosphorus-containing furnace gas; the separation and purification unit is used to separate and purify the phosphorus-containing furnace gas to obtain yellow phosphorus and clean synthesis gas; the grinding and balling unit supplies the obtained phosphorus pellets to the phosphorus coal gasification and reduction unit, the air separation unit supplies gas materials to the phosphorus coal gasification and reduction unit, and the phosphorus-containing furnace gas generated after the reaction in the phosphorus coal gasification and reduction unit enters the separation and purification unit to obtain synthesis gas and yellow phosphorus. The present invention is an efficient and advanced technology for co-producing yellow phosphorus and synthesis gas.

Description

Technical Field

[0001] The invention relates to the field of chemical industry, and in particular to a device and method for co-producing yellow phosphorus and synthesis gas by reducing phosphate ore through pressurized gasification of phosphate coal. Background Art

[0002] Yellow phosphorus is one of the important basic chemical raw materials. It is an important parent raw material for the production of thermal phosphoric acid and phosphides, and an important raw material for the preparation of fine phosphates and fine organic phosphorus chemicals. Currently, there are only two methods for industrial production of yellow phosphorus: blast furnace phosphorus production and electric furnace phosphorus production.

[0003] The process of blast furnace phosphorus production is to use lump phosphate rock as raw material, silica as flux, coke and anthracite as reducing agent and fuel, which are added into the blast furnace in a certain proportion and sequence. In the furnace, the coke is burned with the help of hot air to provide heat, and the remaining coke undergoes chemical reduction reaction with the molten phosphate rock under high temperature conditions. The furnace gas escapes from the top of the blast furnace and is obtained through dust removal equipment and condensation refining device to obtain phosphorus products.

[0004] There are two unsolved problems in the blast furnace method of phosphorus production: First, the reduction rate is low. Although the data of the pilot plant carried out in foreign countries in the 1930s showed that the residual phosphorus in the slag could reach as low as 1.5% (P2O5 content), corresponding to a phosphorus reduction rate of more than 90%, the actual reduction rate achieved by the domestic test device was as high as 73.9%. Second, the economy is poor. The main reason why the blast furnace method of phosphorus production technology in foreign countries in the last century was that the power resources were relatively tight at that time, the electricity price was relatively high, and the price of coke was relatively cheap. With the development of the power generation industry, the power supply is abundant and the electricity price is reduced. Compared with the electric furnace method, the blast furnace method has no cost advantage, and the blast furnace method has gradually lost the market. The electric furnace method produces yellow phosphorus by adding a mixed charge of phosphate ore, silica and coke into the electric furnace, converting the electric energy into heat energy to melt it to produce a chemical reduction reaction, so that the phosphorus in it is sublimated, and the phosphorus-containing furnace gas is condensed, washed, refined and separated to obtain the finished phosphorus. However, the electric furnace method has high energy consumption, heavy pollution, cannot achieve long-term continuous production, and requires high-grade phosphate ore. The current yellow phosphorus production technology can no longer meet the new requirements of low-carbon and environmental protection.

[0005] CN107739025A discloses a device and method for the co-production of phosphorus and coal chemical industry. The device uses the high-temperature crude synthesis gas produced by coal gasification reaction as a heat source for yellow phosphorus production, which not only solves the problem that the heat of the high-temperature section of the crude synthesis gas produced by the coal gasification reaction cannot be utilized, but also can provide heat for yellow phosphorus production, with high energy utilization rate. At the same time, the reaction product CO produced by yellow phosphorus is used together with the crude synthesis gas as a raw material for synthetic ammonia, thereby increasing the output of liquid ammonia products, and the production process is efficient, energy-saving and environmentally friendly. The equipment for the co-production of phosphorus and coal chemical industry includes: a raw material storage and transportation unit, a grinding unit, a pelletizing and drying unit, a reduction reaction unit, a slag cooling unit, a separation and washing unit, an air separation unit, a gasification unit, a conversion unit, a purification unit, and a synthesis unit. The process route is simplified, the technology of each unit is mature, energy-saving and environmentally friendly, and the application risk is small, which provides a beneficial technical choice for the complementarity of phosphorus and coal chemical industry in multiple fields. However, in this technology, the gasification reaction unit and the reduction reaction unit are set separately, occupying a large plant space, and the processing, maintenance and maintenance costs of the equipment are high, and the co-production products are yellow phosphorus and liquid ammonia.

[0006] Therefore, it is of great significance to develop a device and method for gasifying anthracite and simultaneously reducing phosphate ore to generate yellow phosphorus and synthesis gas with high thermal efficiency, optimized process, lower cost, energy saving and environmental protection. Summary of the invention

[0007] In order to solve the above-mentioned defects, the present invention provides a device and a synthesis method for co-producing yellow phosphorus and synthesis gas by reducing phosphate ore through pressurized gasification of phosphate coal.

[0008] The device for co-producing yellow phosphorus and synthesis gas by reducing phosphate ore by pressurized gasification of phosphorus coal described in the present invention comprises a grinding and ball making unit, an air separation unit, a phosphorus coal gasification reduction unit, and a separation and purification unit;

[0009] The powder grinding and pelletizing unit is used to grind part of the raw materials into powder and prepare phosphorus pellets;

[0010] The air separation unit is used to separate air components and prepare oxygen;

[0011] The phosphorus coal gasification and reduction unit: realizes the gasification and reduction reaction of each material in the phosphorus coal gasification and reduction unit to obtain phosphorus-containing furnace gas;

[0012] The separation and purification unit is used to separate and purify the phosphorus-containing furnace gas to obtain yellow phosphorus and clean synthesis gas;

[0013] The grinding and ball making unit supplies the obtained phosphorus pellets to the phosphorus coal gasification and reduction unit, the air separation unit supplies gas materials to the phosphorus coal gasification and reduction unit, and the phosphorus-containing furnace gas produced after the reaction in the phosphorus coal gasification and reduction unit enters the separation and purification unit to obtain synthesis gas and yellow phosphorus.

[0014] Furthermore, the phosphorus coal gasification reduction unit includes a pressurized lock bucket unit, a slag discharge unit, an air inlet, an air outlet, and a reaction unit. The pressurized lock bucket unit is located at the upper part of the reaction unit, and is used to provide a pressurized environment for the fed raw coal and / or coke and the phosphorus pellets; the air inlet is located at the lower side of the reaction unit, and is used to provide the reaction unit with gas materials required for the reaction; the air outlet is located at the upper side of the reaction unit, and is used to discharge the phosphorus-containing furnace gas; the slag discharge unit is located directly below the reaction unit, and is used to discharge the slag generated during the discharge reaction process.

[0015] Furthermore, the pressurized lock bucket unit is a sealed tank body, a connecting pipe extends from the lower part of the tank body to be connected to the reaction unit, and a valve is provided on the connecting pipe.

[0016] Furthermore, at least one coal layer and at least one phosphorus layer are provided in the reaction unit, and the coal layer and the phosphorus layer are arranged in an intermittent manner, the coal layer includes raw coal and / or coke, and the phosphorus layer includes phosphorus pellets, wherein the material layer heights of the coal layer and the phosphorus layer should be set extremely cleverly. If the material layer height is too low, it will lead to insufficient reaction, waste of raw materials and defects of low product yield. If the material layer height is too high, the mixing of materials during the reaction process will be insufficient, the fluidity and contact efficiency of materials in the reaction unit will be insufficient, and the best reaction state cannot be guaranteed, resulting in a huge waste of cost and energy. Therefore, according to the high-temperature heat generated by the gasification reaction of the lower coal layer being equal to the required heat for the reduction reaction of the upper phosphorus layer, the mass of the phosphorus pellets and the raw coal and / or coke is calculated through heat balance, and then the material volume is calculated according to the bulk density of the phosphorus pellets and the raw coal and / or coke, and then the appropriate material layer height ratio is obtained. The appropriate material layer height ratio of the phosphorus layer and the coal layer should be set as follows:

[0017]

[0018]

[0019] Where: H1——height of phosphorus layer consumed per hour, in m;

[0020] H2——height of coal layer consumed per hour, in m;

[0021] Q——The heat required to produce unit mass of yellow phosphorus, in J / kg;

[0022] q——The heat released by the reaction of unit mass of raw coal and / or coke with oxygen, in J / kg;

[0023] M——the mass of yellow phosphorus product, in kg;

[0024] a——Carbon content in raw coal and / or coke, %;

[0025] b——Conversion rate of carbon in raw coal and / or coke, %;

[0026] ρ——Bulk density of raw coal and / or coke, in kg / m 3 ;

[0027] d – diameter of the reaction unit, in m.

[0028] Furthermore, the separation and purification unit includes a cyclone separation system, a multi-stage furnace gas washing system and a furnace gas purification system. After the phosphorus-containing furnace gas is dusted by the cyclone separation system, the yellow phosphorus is recovered by the multi-stage furnace gas washing system. Then, the remaining phosphorus-containing furnace gas containing a small amount of yellow phosphorus is purified by the furnace gas purification system. The purified synthesis gas is used as a raw material for producing ammonia, methanol or ethylene glycol.

[0029] Among them, when part of the dust in the phosphorus-containing furnace gas is dust entrained in the raw materials, and the other part is volatile compounds generated by the volatile matter in the raw materials volatilizing and escaping when encountering high temperature and chemical reactions, the cyclone separation system includes a cyclone separator, a box dust collector or an electrostatic precipitator, etc.; preferably, a cyclone separation system is used for dust removal, that is, to remove solid particles with a particle size greater than 10 microns, thereby reducing the load of the multi-stage furnace gas washing system.

[0030] Furthermore, the main equipment of the cyclone separation system is a cyclone separator, and the main structure includes a cyclone chamber and an ash collecting chamber, wherein the cyclone chamber includes: a shell, a gas inlet, a gas outlet, a dust outlet and a loosening wind inlet. A plurality of cyclone molecules are arranged in the cyclone chamber, each of which is connected to the gas inlet. The phosphorus-containing furnace gas enters each cyclone molecule in the cyclone chamber through the gas inlet, and descends and swirls inside the cyclone molecule, so that the gas and the solid are separated. The phosphorus-containing furnace gas after dust removal is discharged from the gas outlet located at the upper part of the cyclone molecule, and the dust is discharged from the dust outlet located at the lower part of the cyclone molecule. The loosening wind is introduced from the loosening wind inlet to prevent the dust from being blocked at the dust outlet. A small flow of inert gas is introduced to play a loosening role to ensure that the dust is discharged smoothly through the dust outlet.

[0031] Furthermore, the main function of the multi-stage furnace gas washing system is to recover yellow phosphorus. The phosphorus-containing furnace gas obtained after dust removal by the cyclone separation system is introduced into the multi-stage furnace gas washing system to recover yellow phosphorus, wherein spray water is arranged in the multi-stage furnace gas washing system to perform heat exchange with the phosphorus-containing furnace gas in a convection manner, so that the yellow phosphorus vapor is condensed into liquid yellow phosphorus and enters the phosphorus collection device together with the spray water.

[0032] Furthermore, the device also includes a public engineering unit to provide water, electricity, steam and other material supplies for the entire device, wherein the water supply includes production water, domestic water and fire-fighting water, wherein the production water provides cooling water for the entire device; the gas supply includes providing the gas materials required for the reaction of the entire device, and the power supply includes providing power supply for the grinding and ball making unit and providing a lighting environment for the entire device.

[0033] The present invention also provides a method for co-producing yellow phosphorus and synthesis gas by reducing phosphate ore by pressurized gasification of phosphorus coal, which is implemented by the above-mentioned device, wherein at least one coal material layer and at least one phosphorus material layer are provided in the reaction unit, and the coal material layer and the phosphorus material layer are arranged in an alternately laid manner, comprising the following steps:

[0034] S1: crushing and grinding phosphate ore, anthracite and silica by a grinding and pelletizing unit respectively, and mixing them in a mass ratio of phosphate ore: anthracite: silica of (30-80): (10-30): (10-20) to form phosphate pellets, and then feeding the prepared phosphate pellets and raw coal and / or coke into the reaction unit through the pressurized lock hopper unit respectively, wherein the coal material layer includes the raw coal and / or coke, and the phosphorus material layer includes the phosphate pellets;

[0035] S2: The water vapor and the high-purity oxygen treated by the air separation unit are respectively introduced into the reaction unit through the air inlet of the phosphorus coal gasification reduction unit located at the bottom of the reaction unit, and the coal layer located at the bottom of the reaction unit contacts with the oxygen at the bottom of the reaction unit and burns to generate high-temperature furnace gas that flows upward;

[0036] S3: As the furnace gas flows upward, the heat flow and circulation inside the reaction unit is driven, and the materials in the reaction unit are fully mixed and contacted. The pressure in the reaction unit is 1-10MPa and the temperature is 1200-1600°C. The components in the phosphorus pellets undergo chemical reactions to generate elemental phosphorus. The phosphorus-containing furnace gas generated in the reaction unit during the reaction process is discharged from the gas outlet and enters the separation and purification unit;

[0037] S4: In the separation and purification unit, the phosphorus-containing furnace gas is separated, recovered and purified to obtain yellow phosphorus and clean synthesis gas.

[0038] Furthermore, in S1, the phosphate pellet preparation process includes: grinding phosphate rock, anthracite and silica into fine powder of 60-100 mesh, mixing them evenly in a weight ratio of phosphate rock: anthracite: silica = 13:4:3, adding any one or more binders selected from refractory cement, sodium humate, peridot, water glass, and bentonite to press them into pellets with a particle size of 10-30 mm, and after drying, preparing phosphate pellets with a compressive strength of 1800 N / piece.

[0039] Furthermore, in S1, before feeding the reaction unit, the valve between the pressurized lock hopper unit and the reaction unit is first closed, the pressure inside the pressurized hopper is increased to be completely the same as the pressure inside the reaction unit, and then the valve is opened to feed the reaction unit.

[0040] Further, in S2 and S3, the chemical reaction formula in the reaction unit is as follows:

[0041] (1) Coal gasification reaction:

[0042] C+O2=CO2

[0043] 2C+O2=2CO

[0044] C+CO2=2CO

[0045] C+H2O=H2+CO

[0046] C+2H2O=2H2+CO2

[0047] CO+H2O=H2+CO2

[0048] The temperature of the high-temperature furnace gas produced is 1400-1600°C;

[0049] (2) Reduction reaction of phosphorus pellets: The reaction begins in the temperature range of 1152-1177°C. When the temperature reaches about 1227°C, the reaction is almost complete. The reaction formula is:

[0050] Ca3(PO4)2+5C+3SiO2=3CaSiO2+5CO+P2

[0051] When the temperature reaches above 1352℃, the reaction equation is:

[0052] Ca3(PO4)2+5C=3CaO+5CO+P2

[0053] The reduction reaction can proceed spontaneously, and the reaction equilibrium direction tends to the direction of generating P2, so that the yield of the yellow phosphorus product of the present invention (more than 95%) is much higher than the existing yellow phosphorus production technology (no more than 90%).

[0054] Furthermore, the temperature of the reaction unit is mainly controlled by adjusting the ratio of oxygen and water vapor (referred to as oxygen-steam ratio). Under the same load, the lower the oxygen-steam ratio, the lower the gasification temperature and the lower the slag pool temperature; the higher the oxygen-steam ratio, the higher the gasification temperature and the higher the slag pool temperature. A higher oxygen-steam ratio is conducive to the stable operation of the reaction unit, but when it is too high, the refractory bricks of the reaction unit are easily ablated under oxidizing conditions. Therefore, the oxygen-steam ratio is controlled at 1.05-1.1Nm3 / kg operation is relatively stable.

[0055] Further, in S4, the separation and purification unit includes a cyclone separation system, a multi-stage furnace gas washing system and a furnace gas purification system, and includes the following steps:

[0056] The phosphorus-containing furnace gas is passed through the cyclone separation system to remove solid particles with a particle size greater than 10 microns; the obtained phosphorus-containing furnace gas is passed into the multi-stage furnace gas washing system to recover yellow phosphorus, wherein spray water is arranged in the multi-stage furnace gas washing system to perform heat exchange with the phosphorus-containing furnace gas in a convection manner, so that the yellow phosphorus vapor is condensed into liquid yellow phosphorus and enters the phosphorus collection device together with the spray water; and the remaining phosphorus-containing furnace gas containing a small amount of yellow phosphorus is supplied to the furnace gas purification system for further treatment to obtain purified synthesis gas.

[0057] The technical solution provided by the embodiment of the present invention may have the following beneficial effects:

[0058] 1. The device for co-producing yellow phosphorus and synthesis gas of the present invention combines a gasification reaction unit and a reduction reaction unit into one, thereby simplifying the process flow and improving the reliability and stability of the equipment and system.

[0059] 2. The phosphorus coal gasification reduction unit of the present invention realizes the simultaneous gasification reaction and reduction reaction. The high-temperature furnace gas generated by the gasification reaction directly provides reduction reaction heat for the phosphorus pellets, reducing the heat loss of the furnace gas and achieving higher heat utilization rate.

[0060] 3. Water vapor, as a raw material for gasification reaction, not only meets the gasification reaction requirements of raw coal and / or coke, but also can adjust the temperature of the reduction reaction of phosphorus pellets, so that the reduction reaction is carried out in the optimal temperature range of 1200-1400° C., which can greatly improve the yield of yellow phosphorus. On the other hand, the water vapor decomposition rate in the gasification reaction of the present invention is relatively high, and the water vapor content in the furnace gas is very small, so the amount of wastewater generated is relatively small.

[0061] 4. The phosphine coal gasification reduction reaction unit of the present invention further reduces CO2 emissions. Since the CO2 generated by the gasification reaction is reduced to CO by the carbon in the anthracite, the volume content of CO2 in the synthesis gas is reduced to less than 5%. Therefore, the technical solution of the present invention is environmentally friendly and green development.

[0062] 5. The cyclone separation system, multi-stage gas washing system and tail gas purification system are used to separate and purify the phosphorus-containing gas to obtain yellow phosphorus products and purified synthesis gas. The main components of the synthesis gas are CO and H2, which can be used as chemical raw materials to produce synthetic ammonia, methanol or ethylene glycol and other chemical products.

[0063] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0064] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0065] Figure 1 It is a schematic diagram of a process flow of a device and method for co-producing yellow phosphorus and synthesis gas according to an exemplary embodiment;

[0066] Figure 2 is a schematic structural diagram of a phosphorus coal gasification reduction unit according to an exemplary embodiment;

[0067] Figure 3 It is a schematic structural diagram of a cyclone separator according to an exemplary embodiment.

[0068] Figure 1 In: 1-grinding and ball making unit, 2-air separation unit, 3-phosphorus coal gasification reduction unit, 4-separation and purification unit, 31-pressurized lock bucket unit, 32-gas outlet, 33-gas inlet, 34-slag discharge unit, 35-reaction unit, 401-cyclone chamber, 40-shell, 41-cyclone molecules, N1-gas outlet, N2-gas inlet, N3-loosening air inlet, N4-dust outlet. DETAILED DESCRIPTION

[0069] The following description and accompanying drawings fully illustrate specific embodiments of the present invention so that those skilled in the art can practice them. The examples represent possible variations only. Unless explicitly required, separate components and functions are optional, and the order of operations can vary. Parts and features of some embodiments may be included in or replace parts and features of other embodiments. The scope of the embodiments of the present invention includes the entire scope of the claims, and all available equivalents of the claims. In this article, each embodiment may be represented individually or generally by the term "invention", which is only for convenience, and if more than one invention is in fact disclosed, it is not intended to automatically limit the scope of the application to any single invention or inventive concept. In this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, without requiring or implying any actual relationship or order between these entities or operations. Moreover, the term "include", "comprise" or any other variant thereof is intended to cover non-exclusive inclusion, so that the process, method or device including a series of elements includes not only those elements, but also other elements that are not explicitly listed. The various embodiments are described in a progressive manner herein, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other. As for the structures, products, etc. disclosed in the embodiments, since they correspond to the parts disclosed in the embodiments, the description is relatively simple, and the relevant parts can be referred to the description of the method part.

[0070] The present invention will be further described below in conjunction with the accompanying drawings and embodiments:

[0071] Figure 1 FIG. 1 is a schematic diagram of a process flow diagram of an apparatus and method for co-producing yellow phosphorus and synthesis gas according to an exemplary embodiment. Figure 1 As shown, the device includes a coal grinding and pelletizing unit 1, an air separation unit 2, a phosphorus coal gasification and reduction unit 3, and a separation and purification unit 4; the coal grinding and pelletizing unit 1 is mainly used to grind the raw materials into powder and prepare phosphorus pellets; the air separation unit 2 is mainly used to separate air components and prepare oxygen; the phosphorus coal gasification and reduction unit 3 is mainly used to realize the gasification and reduction reaction of phosphorus coal pellets, raw coal or coke, oxygen and water vapor, etc., to obtain phosphorus-containing furnace gas; the separation and purification unit 4 is mainly used to separate and purify the phosphorus-containing furnace gas to obtain finished yellow phosphorus and clean synthesis gas.

[0072] When the device implements the process of co-producing yellow phosphorus and synthesis gas, raw coal and / or coke and phosphorus pellets produced by the grinding and pelletizing unit 1 are added in sequence from the top of the phosphorus coal gasification and reduction unit 3, and water vapor and high-purity oxygen obtained by the air separation unit 2 are added from the bottom of the phosphorus coal gasification and reduction unit 3. In the phosphorus coal gasification and reduction unit 3, gasification reaction and reduction reaction occur simultaneously. The high-temperature furnace gas produced by the gasification reaction directly provides reduction reaction heat for the phosphorus pellets, the slag produced by the reaction is discharged from the bottom, and the crude product phosphorus-containing furnace gas is extracted from the top and supplied to the separation and purification unit 4 to obtain yellow phosphorus and clean synthesis gas.

[0073] The coal grinding and pelletizing unit 1 is connected to the phosphate coal gasification reduction unit 3, and includes a crusher, a coal mill, a batching bin, a pelletizing machine and a dryer. In the specific operation, the phosphate rock, anthracite and silica powder are crushed in the crusher, respectively, and then sent to the coal mill to be ground into 80 mesh fine powder, and the ground powders are transported to the batching bin, and mixed evenly according to the weight ratio of phosphate rock: anthracite: silica = 13:4:3, and bentonite is added as a binder, and then sent to the ball making machine to make phosphate pellets, and finally dried in a dryer to obtain qualified phosphate pellets with an average particle size of 20mm and a compressive strength of 1800N / piece.

[0074] The air separation unit 2 is connected to the phosphorus coal gasification reduction unit 3, and is used to compress the air and cool it to a temperature of -196°C, or to liquefy and separate the air by an expansion method to obtain oxygen with a purity of 98.0% to 99.9%.

[0075] The separation and purification unit 4 is connected to the phosphorus coal gasification and reduction unit 3, and the separation and purification unit 4 includes a cyclone separator, a three-stage furnace gas washing system and a furnace gas purification system. In specific operation, the phosphorus-containing furnace gas derived from the phosphorus coal gasification and reduction unit 3 is removed by a cyclone separator with solid particles having a particle size greater than 10 microns, and then the obtained phosphorus-containing furnace gas is sent to the three-stage furnace gas washing system, wherein the three-stage furnace gas washing system is provided with spray water and the phosphorus-containing furnace gas in a convection manner for heat exchange, so that the yellow phosphorus vapor is condensed into liquid yellow phosphorus and enters the phosphorus collecting device together with the spray water, and finally the remaining phosphorus-containing furnace gas containing a small amount of yellow phosphorus is supplied to the furnace gas purification system, and is purified by a low-temperature methanol washing or liquid nitrogen washing process to obtain a purified synthesis gas, the main components of which are CO and H2, and the obtained synthesis gas can be used as a raw material for chemical production to further synthesize ammonia, methanol or ethylene glycol.

[0076] Figure 2 FIG. 1 is a schematic diagram of a phosphorus coal gasification reduction unit according to an exemplary embodiment. Figure 2 As shown, the phosphorus coal gasification reduction unit includes a pressurized lock bucket unit 31, a gas outlet 32, a gas inlet 33, a slag discharge unit 34 and a reaction unit 35.

[0077] The pressurized lock bucket unit 31 is a sealed tank body, and a connecting pipe extends from the lower part of the tank body and is connected to the upper part of the reaction unit 35, and a valve is provided on the connecting pipe. The pressurized lock bucket unit 31 includes a hemispherical upper head, a cylindrical straight section, and a cone lower cone head, which are connected in sequence as a whole to provide a pressurized environment for the fed raw coal and / or coke, and phosphorus pellets; the slag discharge unit 34 is located directly below the reaction unit 35 and is connected to the reaction unit 35, and includes a cone and a tubular body, which are connected in sequence as a whole to discharge the slag generated during the reaction process; the air inlet 33 is located at the lower left of the reaction unit 35 and is connected to the reaction unit 35, and is used to provide water vapor and high-purity oxygen to the reaction unit 35; the air outlet 32 ​​is located at the upper right of the reaction unit 35 and is connected to the reaction unit 35, and is used to discharge phosphorus-containing furnace gas.

[0078] In this embodiment, two coal layers and two phosphorus layers are provided in the phosphorus coal gasification reduction unit. The coal layers and the phosphorus layers are arranged in an interlaced manner so that the coal layers are below the phosphorus layers. The coal layers include raw coal and / or coke, and the phosphorus layers include phosphorus pellets. The material layer height ratio of the coal layers and the phosphorus layers is H1 / H2=1.4.

[0079] The specific operation process is as follows: First, Figure 1 The phosphorus pellets and raw coal in the scheme shown are sequentially fed into the reaction unit 35 through the pressurized lock hopper unit 31. Before feeding the reaction unit 35, the valve between the pressurized lock hopper unit 31 and the reaction unit 35 is closed, the pressure inside the pressurized lock hopper unit 31 is increased to 4.0 MPa, so that it is exactly the same as the pressure inside the reaction unit 35, and then the valve is opened for feeding. High-purity oxygen and water vapor are mixed at an oxygen-to-gas ratio of 1.1 Nm 3 / kg is introduced from the air inlet 33. Subsequently, in the reaction unit 35, the raw coal reacts with oxygen and water vapor in the coal layer to produce 1500°C high-temperature furnace gas flowing upward. As the high-temperature furnace gas flows upward, it drives the overall heat flow and circulation inside the reaction unit 35, and promotes the full mixing and contact of the materials. The high-temperature furnace gas heats the adjacent upper phosphorus pellets to 1300°C, and maintains the reaction time for 30 minutes, so that the phosphorus pentoxide in the phosphorus pellets is reduced to elemental phosphorus. At this time, the reaction unit maintains a pressure of 4.0MPa and a temperature of 1400°C. After the reaction is complete, the phosphorus-containing furnace gas (the content ratio of elemental phosphorus to furnace gas is 1:25) generated by the reaction is exported from the gas outlet 32 ​​to the separation and purification unit, and the slag is discharged by the slag discharge unit 34.

[0080] Figure 3It is a schematic diagram of the structure of a cyclone separator according to an exemplary embodiment, the main structure includes a cyclone chamber 401 and an ash collecting chamber (not shown in the figure), wherein the cyclone chamber 401 is provided with a shell 40, a gas outlet N1, a gas inlet N2, a loosening wind inlet N3 and a dust outlet N4. A plurality of cyclone molecules 41 are provided in the cyclone chamber 401, each of which is connected to the gas inlet N1, and the phosphorus-containing furnace gas enters each cyclone molecule 41 of the cyclone chamber 401 through the gas inlet N2, and descends and swirls inside the cyclone molecule 41, so that the gas and the solid are separated, and the phosphorus-containing furnace gas after dust removal is discharged from the gas outlet N1 located at the upper part of the cyclone molecule 41, and the dust is discharged from the dust outlet N4 located at the lower part of the cyclone molecule 41, and the loosening wind inlet N3 introduces inert gas to ensure that the dust is discharged smoothly through the dust outlet N4.

[0081] The present invention is based on the principle of yellow phosphorus preparation, combined with the characteristics of the production process of syngas, the raw material has carbon, and the reaction process produces heat, the production of yellow phosphorus and syngas is combined, and the material layer height ratio H1 / H2 of the coal material layer and the phosphorus material layer in the phosphorus coal gasification reduction unit and the oxygen-gas ratio of the gas material are further adjusted, and the phosphorus reduction process and the coal gasification process are combined into one, so that the product phosphorus yield (more than 95%) obtained by the technical solution of the present invention is much higher than the existing yellow phosphorus production technology (no more than 90%). In addition, the present invention can also achieve a carbon conversion rate of more than 99.8% for anthracite gasification, a water vapor decomposition rate of more than 96%, and the discharged slag is in a harmless glass state, and the amount of wastewater is reduced by 20%, which is a significant improvement compared with the existing technical indicators.

[0082] It should be understood that the present invention is not limited to the processes and structures described above and shown in the drawings, and various modifications and changes can be made without departing from the scope thereof. The scope of the present invention is limited only by the appended claims.

Claims

1. A method for co-producing yellow phosphorus and synthesis gas by reducing phosphate ore by pressurized gasification of phosphorus coal, characterized in that: At least one coal material layer and at least one phosphorus material layer are provided in the reaction unit (35), wherein the coal material layer and the phosphorus material layer are arranged in an alternate manner, and the following steps are included: S1: phosphate rock, anthracite and silica are crushed and ground by a grinding and pelletizing unit respectively, and mixed in a mass ratio of phosphate rock: anthracite: silica of (30-80): (10-30): (10-20) to form phosphate pellets, and then the prepared phosphate pellets and raw coal and / or coke are fed into the reaction unit (35) through a pressurized lock hopper unit (31), wherein the coal material layer includes the raw coal and / or coke, and the phosphorus material layer includes the phosphate pellets; S2: Water vapor and high-purity oxygen treated by the air separation unit (2) are introduced into the reaction unit (35) through the air inlet (33) located at the bottom of the reaction unit (35) of the phosphorus coal gasification reduction unit (3), respectively, with an oxygen-gas ratio of 1.05 to 1.1 Nm 3 / kg, the coal layer located at the bottom of the reaction unit (35) contacts with oxygen at the bottom of the reaction unit (35), burns and generates high-temperature furnace gas that flows upward; S3: As the furnace gas flows upward, it drives the heat flow and circulation inside the reaction unit (35) as a whole, and at the same time promotes the full mixing and contact of the materials in the reaction unit (35). The pressure in the reaction unit (35) is 1-10 MPa and the temperature is 1200-1600° C. The components in the phosphorus pellets undergo a chemical reaction to generate elemental phosphorus. The phosphorus-containing furnace gas generated in the reaction process in the reaction unit (35) is discharged from the gas outlet (32) and enters the separation and purification unit (4); S4: In the separation and purification unit (4), the phosphorus-containing furnace gas is separated, recovered and purified to obtain yellow phosphorus and clean synthesis gas; The method is implemented by using a device for co-producing yellow phosphorus and synthesis gas by pressurized gasification and reduction of phosphate ore, the device comprising a grinding and ball making unit, an air separation unit, a phosphate coal gasification and reduction unit, and a separation and purification unit; The grinding and ball making unit (1) supplies the obtained phosphorus pellets to the phosphorus coal gasification and reduction unit (3), the air separation unit (2) supplies the gaseous material to the phosphorus coal gasification and reduction unit (3), and the phosphorus-containing furnace gas generated after the reaction in the phosphorus coal gasification and reduction unit (3) enters the separation and purification unit (4) to obtain synthesis gas and yellow phosphorus; In S1, the material layer height ratio of the phosphorus material layer and the coal material layer is set as follows: Where: H1——height of phosphorus layer consumed per hour, in m; H2——height of coal layer consumed per hour, in m; Q——The heat required to produce unit mass of yellow phosphorus, in J / kg; q——The heat released by the reaction of unit mass of raw coal and / or coke with oxygen, in J / kg; M——the mass of yellow phosphorus product, in kg; a——Carbon content in raw coal and / or coke, %; b——Conversion rate of carbon in raw coal and / or coke, %; ρ——Bulk density of raw coal and / or coke, in kg / m 3 ; d – diameter of the reaction unit, in m.

2. The method according to claim 1, characterized in that: The phosphorus coal gasification reduction unit (3) comprises a pressurized lock hopper unit (31), a slag discharge unit (34), an air inlet (33), an air outlet (32), and a reaction unit (35). The pressurized lock hopper unit (31) is located at the upper part of the reaction unit (35) and is used to provide a pressurized environment for the feed raw coal and / or coke and the phosphorus pellets; the air inlet (33) is located at the lower side of the reaction unit and is used to provide the reaction unit (35) with gas materials required for the reaction; the air outlet (32) is located at the upper side of the reaction unit (35) and is used to discharge the phosphorus-containing furnace gas; the slag discharge unit (34) is located directly below the reaction unit (35) and is used to discharge the slag generated during the discharge reaction.

3. The method according to claim 2, characterized in that The pressurized lock bucket unit (31) is a sealed tank body, a connecting pipe extends from the lower part of the tank body to be connected to the reaction unit, and a valve is provided on the connecting pipe.

4. The method according to claim 1, characterized in that The separation and purification unit (4) comprises a cyclone separation system, a multi-stage furnace gas washing system and a furnace gas purification system. After dust removal by the cyclone separation system, the multi-stage furnace gas washing system is used to recover yellow phosphorus. The remaining phosphorus-containing furnace gas containing a small amount of yellow phosphorus is then purified by the furnace gas purification system. The purified synthesis gas is used as a raw material for producing ammonia, methanol or ethylene glycol.

5. The method according to claim 1, characterized in that It also includes a public engineering unit, which provides water, electricity, and gas materials for the entire device. The water supply includes production water, domestic water, and fire-fighting water, among which the production water provides cooling water for the entire device; the gas supply includes providing the gas materials required for the reaction of the entire device, and the power supply includes providing power supply for the grinding and ball making unit and providing a lighting environment for the entire device.

6. The method according to claim 1, characterized in that In S1, phosphate rock, anthracite and silica are ground into fine powder of 60-100 mesh, uniformly mixed in a weight ratio of phosphate rock: anthracite: silica = 13:4:3, and any one or more binders selected from refractory cement, sodium humate, peridot, water glass and bentonite are added to press into pellets with a particle size of 10-30 mm, and after drying, phosphate pellets with a compressive strength of 1800 N / piece are prepared.

7. The method according to claim 1, characterized in that In S1, before feeding the reaction unit (35), the valve between the pressurizing lock bucket unit (31) and the reaction unit (35) is first closed, the pressure inside the pressurizing lock bucket unit (31) is increased to be completely the same as the pressure inside the reaction unit (35), and then the valve is opened to feed the reaction unit (35).

8. The method according to claim 1, characterized in that: In S4, the separation and purification unit (4) comprises a cyclone separation system, a multi-stage furnace gas washing system and a furnace gas purification system, and comprises the following steps: The phosphorus-containing furnace gas is passed through the cyclone separation system to remove solid particles with a particle size greater than 10 microns; the obtained phosphorus-containing furnace gas is passed into the multi-stage furnace gas washing system to recover yellow phosphorus, wherein spray water is arranged in the multi-stage furnace gas washing system to perform heat exchange with the phosphorus-containing furnace gas in a convection manner, so that the yellow phosphorus vapor is condensed into liquid yellow phosphorus and enters the phosphorus collection device together with the spray water; and the remaining phosphorus-containing furnace gas containing a small amount of yellow phosphorus is supplied to the furnace gas purification system for further treatment to obtain purified synthesis gas.

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