Flue gas desulfurization method for preparing ammonia by combining phosphoric ore pulp with renewable energy

Abstract

The invention relates to a flue gas desulfurization method for ammonia production by combining phosphoric ore pulp with renewable energy sources, which comprises the following steps: desulfurizing SO2-containing flue gas by using the phosphoric ore pulp to obtain a phosphoric ore pulp absorption liquid; preparing ammonia gas by using a clean energy ammonia preparation system, introducing the ammonia gas into the buffered phosphoric ore pulp absorption liquid, carrying out solid-liquid separation on reactants to obtain an ammonium phosphate solution and calcium sulfate, feeding the ammonium phosphate solution into a granulator, granulating, drying particles, and screening to obtain ammonium phosphate, and simultaneously realizing flue gas desulfurization. The flue gas desulfurization method for preparing ammonia by combining the phosphoric ore pulp and the renewable energy has the advantages of high efficiency, high utilization rate, less pollution and resource utilization.

Description

Technical Field

[0001] The invention belongs to the technical field of metal smelting flue gas treatment, and specifically relates to a flue gas desulfurization method for producing ammonia using phosphate slurry combined with renewable energy. Background Art

[0002] During the ore smelting process, a large amount of flue gas is produced, causing serious environmental pollution. Among them, sulfur dioxide (SO2) is an important precursor of acid rain and haze, which can cause pollution of the atmosphere, water bodies, soil, etc., and seriously harm the ecological environment. At present, the limestone-gypsum method is widely used as a wet flue gas desulfurization method, but this process occupies a large area, and the by-product gypsum has a high output in my country and is often directly discarded without resource recycling; in the face of increasingly stringent emission standards, it is urgent to develop a flue gas desulfurization technology that is efficient, stable in operation, and has high added value. Summary of the invention

[0003] In view of this, the purpose of the present invention is to provide a flue gas desulfurization method for producing ammonia by combining phosphate slurry with renewable energy, which has the advantages of high efficiency, high utilization rate, less pollution and resource utilization.

[0004] The present invention solves the above problems by the following technical means:

[0005] The invention discloses a flue gas desulfurization method for producing ammonia by combining phosphate slurry with renewable energy, wherein phosphate slurry is used to desulfurize flue gas containing SO2 to obtain phosphate slurry absorption liquid; ammonia is produced by a clean energy ammonia production system, and the ammonia is introduced into the buffered phosphate slurry absorption liquid, reactants are separated into solid and liquid to obtain ammonium phosphate solution and calcium sulfate, the ammonium phosphate solution is sent to a granulator for granulation, the particles are dried, and ammonium phosphate is obtained after screening, and flue gas desulfurization is achieved at the same time.

[0006] Furthermore, the clean energy ammonia production system includes a photothermal heat collection system, a photothermal heat storage system, a clean energy electrolysis hydrogen production system and an ammonia synthesis tower.

[0007] Furthermore, the clean energy electrolysis hydrogen production system includes a clean energy power generation system, a junction box and an energy storage battery assembly and an electrolyzer. The clean energy power generation system generates electricity using wind energy and / or electric energy. The clean energy power generation system is connected to the junction box and the energy storage battery assembly. The junction box and the energy storage battery assembly are connected to the electrolyzer, so that the current generated by the clean energy power generation system is supplied to the electrolyzer through the junction box and the energy storage battery, so that the electrolyzer generates hydrogen by electrolysis.

[0008] Furthermore, it also includes an air separator, a gas mixing container, a gas compression device and an ammonia cooling tower. The air separator separates air to produce nitrogen, the gas mixing container mixes hydrogen and nitrogen, the gas compression device compresses the mixed gas, and the compressed mixed gas passes through an ammonia synthesis tower to undergo a synthetic ammonia reaction, and the synthesized ammonia is cooled by the ammonia cooling tower.

[0009] Furthermore, the photothermal heat collection system is used to receive solar energy and generate heat. The heat generated by the photothermal heat collection system uses heat transfer oil as a heat conduction carrier and is stored in a filled bed type heat storage tank.

[0010] Furthermore, when ammonia gas is introduced into the buffered phosphate slurry absorption liquid, the phosphate slurry absorption liquid is stirred.

[0011] Furthermore, an electromagnetic field is applied when ammonia gas is passed into the buffered phosphate slurry absorption liquid.

[0012] Beneficial effects of the present invention:

[0013] The phosphate slurry combined with renewable energy to produce ammonia flue gas desulfurization method of the present application uses phosphate slurry to desulfurize flue gas containing SO2 to obtain phosphate slurry absorption liquid; uses a clean energy ammonia production system to produce ammonia, passes ammonia into the buffered phosphate slurry absorption liquid, separates the reactants into solid and liquid, obtains ammonium phosphate solution and calcium sulfate, sends the ammonium phosphate solution into a granulator for granulation, dries the granules, and obtains ammonium phosphate after screening, and simultaneously achieves flue gas desulfurization. The phosphate slurry combined with renewable energy to produce ammonia flue gas desulfurization method of the present application has the advantages of high efficiency, high utilization rate, less pollution and resource utilization. DETAILED DESCRIPTION

[0014] The present invention is further described in detail by way of examples below. Through these descriptions, the features and advantages of the present invention will become clearer and more specific. Obviously, the described embodiments are only a part of the embodiments of the present invention, not all of them.

[0015] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicating the orientation or position relationship are based on the orientation or position relationship shown, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0016] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0017] The embodiment of the present invention discloses a flue gas desulfurization method for ammonia production using phosphate slurry in combination with renewable energy, wherein phosphate slurry is used to desulfurize flue gas containing SO2 to obtain phosphate slurry absorption liquid; ammonia is produced by using a clean energy ammonia production system, and the ammonia is introduced into the buffered phosphate slurry absorption liquid, and the reactants are separated into solid and liquid to obtain ammonium phosphate solution and calcium sulfate, and the ammonium phosphate solution is sent to a granulator for granulation, and the particles are dried and sieved to obtain ammonium phosphate, and flue gas desulfurization is achieved at the same time.

[0018] The clean energy ammonia production system includes a solar thermal collection system, a solar thermal heat storage system, a clean energy electrolytic hydrogen production system and an ammonia synthesis tower. The clean energy electrolytic hydrogen production system includes a clean energy power generation system, a junction box and an energy storage battery assembly and an electrolyzer. The clean energy power generation system generates electricity using wind energy and / or electric energy. The clean energy power generation system is connected to the junction box and the energy storage battery assembly. The junction box and the energy storage battery assembly are connected to the electrolyzer, so that the current generated by the clean energy power generation system is supplied to the electrolyzer through the junction box and the energy storage battery, so that the electrolyzer generates hydrogen by electrolysis.

[0019] It also includes an air separator, a gas mixing container, a gas compression device and an ammonia cooling tower. The air separator separates air to produce nitrogen, the gas mixing container mixes hydrogen and nitrogen, the gas compression device compresses the mixed gas, and the compressed mixed gas passes through an ammonia synthesis tower to undergo a synthetic ammonia reaction, and the synthesized ammonia is cooled by the ammonia cooling tower.

[0020] The photothermal heat collection system is used to receive solar energy and generate heat. The heat generated by the photothermal heat collection system uses heat transfer oil as a heat conduction carrier and is stored in a filled bed type heat storage tank.

[0021] The electrolyzer is any one of an alkaline electrolyzer and a proton exchange membrane electrolyzer. In this embodiment, the electrolyzer is an alkaline electrolyzer, the electrolyte in the electrolyzer is a 30% potassium hydroxide solution or includes a proton exchange membrane, the working temperature of the electrolyzer is 70-90°C, and the clean energy power generation system can provide electricity for the electrolysis of the electrolyzer, so that the hydrogen generated after the electrolysis of the electrolyzer can be supplied to the ammonia synthesis tower for reaction to prepare ammonia, and the oxygen obtained by electrolysis can be directly discharged or sold at the price of pure oxygen after separation and purification.

[0022] The solar thermal collection system has a heat collection method of one or more of trough heat collection, dish heat collection or tower heat collection.

[0023] It is understandable that since the process of preparing ammonia requires raw materials hydrogen and nitrogen, as well as high-temperature heating, the solar thermal collection system absorbs solar energy to generate heat, and the excess heat can be collected by the solar thermal storage system. Phase change materials in different temperature zones can be used to supply heat to different temperature zones. On the one hand, it can be supplied to the electrolyzer for heating, and on the other hand, it can be supplied to the ammonia synthesis tower for heating.

[0024] Preferably, when ammonia is passed into the buffered phosphate slurry absorption liquid, the phosphate slurry absorption liquid is stirred to improve the uniformity of mixing of ammonia and phosphate slurry; further preferably, when ammonia is passed into the buffered phosphate slurry absorption liquid, an electromagnetic field is applied to improve the fluidity of the slurry by applying electromagnetic force to the slurry.

[0025] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the purpose and scope of the technical solution of the present invention, which should be included in the scope of the claims of the present invention.

Claims

1. A flue gas desulfurization method for producing ammonia using phosphate slurry combined with renewable energy, characterized in that: Phosphate slurry is used to desulfurize flue gas containing SO2 to obtain phosphate slurry absorption liquid; Ammonia is produced by using a clean energy ammonia production system, and then introduced into the buffered phosphate slurry absorption liquid. The reactants are separated into solid and liquid to obtain ammonium phosphate solution and calcium sulfate. The ammonium phosphate solution is sent to a granulator for granulation, and the particles are dried and sieved to obtain ammonium phosphate, while flue gas desulfurization is achieved at the same time.

2. The flue gas desulfurization method for producing ammonia from phosphate slurry combined with renewable energy according to claim 1, characterized in that: The clean energy ammonia production system includes a photothermal heat collection system, a photothermal heat storage system, a clean energy electrolytic hydrogen production system and an ammonia synthesis tower.

3. The flue gas desulfurization method for producing ammonia using phosphate slurry combined with renewable energy according to claim 2, characterized in that: The clean energy electrolysis hydrogen production system includes a clean energy power generation system, a junction box and an energy storage battery assembly and an electrolyzer. The clean energy power generation system generates electricity using wind energy and / or electric energy. The clean energy power generation system is connected to the junction box and the energy storage battery assembly. The junction box and the energy storage battery assembly are connected to the electrolyzer, so that the current generated by the clean energy power generation system is supplied to the electrolyzer through the junction box and the energy storage battery, so that the electrolyzer generates hydrogen by electrolysis.

4. The flue gas desulfurization method for producing ammonia using phosphate slurry combined with renewable energy according to claim 3, characterized in that: It also includes an air separator, a gas mixing container, a gas compression device and an ammonia cooling tower. The air separator separates air to produce nitrogen, the gas mixing container mixes hydrogen and nitrogen, the gas compression device compresses the mixed gas, and the compressed mixed gas passes through an ammonia synthesis tower to undergo a synthetic ammonia reaction, and the synthesized ammonia is cooled by the ammonia cooling tower.

5. The flue gas desulfurization method for producing ammonia using phosphate slurry combined with renewable energy according to claim 4, characterized in that: The photothermal heat collection system is used to receive solar energy and generate heat. The heat generated by the photothermal heat collection system uses heat transfer oil as a heat conduction carrier and is stored in a filled bed type heat storage tank.

6. The flue gas desulfurization method for producing ammonia from phosphate slurry combined with renewable energy according to claim 5, characterized in that: When ammonia gas is introduced into the buffered phosphate slurry absorption liquid, the phosphate slurry absorption liquid is stirred.

7. The flue gas desulfurization method for producing ammonia using phosphate slurry combined with renewable energy according to claim 6, characterized in that: An electromagnetic field is applied while passing ammonia gas into the buffered phosphate slurry absorbent.