Energy-saving evaporator device for ammonium nitrate solution
By designing an energy-saving ammonium nitrate solution energy-saving evaporator device using high-temperature alkaline steam as a heat source, the problem of the inability to utilize heat from high-temperature alkaline steam in the prior art is solved, and efficient energy utilization and production cost reduction are achieved.
Patent Information
- Application Number
- CN202422160547.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-04
- Publication Date
- 2025-06-17
- Estimated Expiration
- 2034-09-04
AI Technical Summary
In the existing ammonium nitrate production process, the heat of high-temperature alkaline steam generated by neutralization reaction of dilute nitric acid and gas ammonia acid-base cannot be utilized, resulting in waste of energy and increasing production costs.
An energy-saving evaporator device for ammonium nitrate solution is designed to use high-temperature alkaline steam generated by neutralization reaction as a heat source to evaporate the dilute nitric acid solution by vacuum descent film, reduce the use of saturated steam, and realize the recycling of heat.
The heat of high-temperature alkaline steam is effectively utilized, the use of saturated steam is reduced, the production cost is reduced, and the energy utilization rate is improved.
Smart Images
Figure CN222983725U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of the chemical industry, and particularly relates to an energy-saving evaporator device for ammonium nitrate solution. Background Technique
[0002] At present, domestic ammonium nitrate production enterprises mainly adopt two production processes, namely tubular reactors and volumetric reactors, to produce ammonium nitrate. Compared with the tubular reactor method, the pressurized volumetric reactor process flow is more concise, occupies less land area, and has a higher automation level. It is also the future development direction of ammonium nitrate production processes. The pressurized volumetric reaction method uses dilute nitric acid with a concentration of 58%-65% and gaseous ammonia for acid-base pressurized neutralization reaction to generate dilute ammonium nitrate solution with a concentration of 75-80%. However, most enterprises using ammonium nitrate solution use ammonium nitrate solution with a concentration of about 90%-93%. Therefore, it is necessary to concentrate the dilute ammonium nitrate solution. Most enterprises adopt a vacuum falling film single-stage evaporator, using saturated steam as the heat source. Under vacuum, the ammonium nitrate solution is concentrated. The dilute ammonium nitrate solution with a concentration of about 75%-80% out of the neutralizer can be concentrated to ammonium nitrate solution with a concentration of 90%-93% for external sale of ammonium nitrate solution or subsequent further concentration for the production of nitro compound fertilizers.
[0003] Directly using saturated steam for heating will cause an increase in production costs. Moreover, the acid-base neutralization reaction between dilute nitric acid and gaseous ammonia itself is an exothermic reaction. The temperature of the high-temperature alkaline steam containing ammonia generated is between 160-180°C, and the heat cannot be utilized, resulting in waste of energy. Therefore, an energy-saving evaporator device for ammonium nitrate solution is proposed to solve the above problems. Content of the Utility Model
[0004] The purpose of the utility model is to provide an energy-saving evaporator device for ammonium nitrate solution to solve the problems put forward in the above background technique.
[0005] To achieve the above purpose, the utility model provides the following technical solutions:
[0006] As an optional scheme of an energy-saving evaporator device for ammonium nitrate solution of the utility model, wherein: an energy-saving evaporator device for ammonium nitrate solution includes a single-stage evaporator, an inlet for dilute ammonium nitrate solution, and an outlet for concentrated ammonium nitrate solution.
[0007] The inlet for dilute ammonium nitrate solution vertically arranged is installed at the top of the single-stage evaporator, and the outlet for concentrated ammonium nitrate solution is installed at the bottom of the single-stage evaporator.
[0008] The alkaline steam inlet and the alkaline steam condensate outlet distributed up and down are installed on the side of the single-stage evaporator. A second regulating valve is installed on the outer pipe of the alkaline steam inlet.
[0009] A gas-phase balance port communicating with the first-stage evaporator is provided between the alkaline steam inlet and the alkaline steam condensate outlet, and a gas-phase condensate outlet is installed on the other side of the first-stage evaporator.
[0010] The outer side of the bottom of the first-stage evaporator is fixedly connected with a heating pipe, and one end of the heating pipe is fixedly connected with a heat-preserving steam inlet, and the other end of the heating pipe is fixedly connected with a heat-preserving steam condensate outlet.
[0011] As an alternative scheme of the energy-saving evaporator device for ammonium nitrate solution of the present utility model, wherein: a first regulating valve is installed on the outer side of the external connection pipe of the heat-preserving steam inlet.
[0012] Directly using saturated steam for heating will cause an increase in production costs. Moreover, the neutralization reaction between dilute nitric acid and amino acid alkali itself is an exothermic reaction, and the temperature of the generated high-temperature alkaline steam containing ammonia is between 160-180°C, and the heat cannot be utilized, resulting in energy waste. In this device, during the startup stage, saturated steam from the saturated steam pipe network is transported to the heat-preserving steam inlet to preheat and keep warm the first-stage evaporator, and the generated condensate is discharged through the heat-preserving steam condensate outlet to prevent the ammonium nitrate material from crystallizing due to low temperature after entering the first-stage evaporator. During the normal production stage, the first valve is closed, and the saturated steam stops being continuously transported to the heat-preserving steam inlet. The second regulating valve is opened, and the first-stage vacuum falling-film evaporator uses the high-temperature alkaline steam generated by the neutralization reaction from the neutralizer as a heat source, enters through the alkaline steam inlet, and the condensate is discharged through the alkaline steam condensate outlet. The heat of the alkaline steam is used to perform vacuum falling-film evaporation on the dilute nitric acid solution, reducing the usage amount of saturated steam and simultaneously realizing the energy utilization of the high-temperature alkaline steam.
[0013] As an alternative scheme of the energy-saving evaporator device for ammonium nitrate solution of the present utility model, wherein: the heating pipe is spirally arranged at the bottom of the first-stage evaporator.
[0014] As an alternative scheme of the energy-saving evaporator device for ammonium nitrate solution of the present utility model, wherein: the heating pipe is made of stainless steel pipe.
[0015] When performing heat recycling, the steam moves inside the heating pipe. Since the heating pipe is made of stainless steel pipe with good heat dissipation, it can effectively perform energy exchange.
[0016] Compared with the prior art, the beneficial effects of the present utility model are:
[0017] The present utility model is an energy-saving evaporator device that uses the alkaline steam generated by the ammonium nitrate reaction to evaporate the ammonium nitrate solution, realizes the energy utilization of the temperature of the high-temperature alkaline steam during the continuous production process, and simultaneously reduces the usage of saturated steam and the production cost. Description of the Drawings
[0018] Figure 1 This is the overall structural schematic diagram of the present utility model.
[0019] In the figure: 1. Alkaline steam inlet; 2. Dilute ammonium nitrate solution inlet; 3. Alkaline steam condensate outlet; 4. Gas-phase condensate outlet; 5. Concentrated ammonium nitrate solution outlet; 6. Heat preservation steam inlet; 7. Heat preservation steam condensate outlet; 8. Gas-phase balance port; 9. First-stage evaporator; 10. Heating tube; 11. First regulating valve; 12. Second regulating valve. Specific embodiments
[0020] Next, the technical solutions in the embodiments of the present utility model will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present utility model. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all the embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present utility model.
[0021] Embodiment 1
[0022] Please refer to Figure 1 , the present utility model provides a technical solution:
[0023] An energy-saving evaporator device for ammonium nitrate solution, comprising a first-stage evaporator 9, a dilute ammonium nitrate solution inlet 2 and a concentrated ammonium nitrate solution outlet 5,
[0024] The above-mentioned first-stage evaporator 9 is provided with a vertically arranged dilute ammonium nitrate solution inlet 2 at the top, and a concentrated ammonium nitrate solution outlet 5 is installed at the bottom of the above-mentioned first-stage evaporator 9;
[0025] The side of the above-mentioned first-stage evaporator 9 is provided with an alkaline steam inlet 1 and an alkaline steam condensate outlet 3 which are distributed up and down. A second regulating valve 12 is installed on the outer pipe of the above-mentioned alkaline steam inlet 1;
[0026] A gas-phase balance port 8 communicating with the first-stage evaporator 9 is arranged between the above-mentioned alkaline steam inlet 1 and the alkaline steam condensate outlet 3, and a gas-phase condensate outlet 4 is installed on the other side of the above-mentioned first-stage evaporator 9;
[0027] The bottom outer side of the above-mentioned first-stage evaporator 9 is fixedly connected with a heating tube 10, and one end of the heating tube 10 is fixedly connected with a heat preservation steam inlet 6, and the other end of the heating tube 10 is fixedly connected with a heat preservation steam condensate outlet 7.
[0028] A first regulating valve 11 is installed on the outer pipe of the above-mentioned heat preservation steam inlet 6.
[0029] Directly using saturated steam for heating will result in an increase in production costs. Moreover, the neutralization reaction between dilute nitric acid and amino acid alkali itself is an exothermic reaction. The high-temperature alkaline steam containing ammonia generated has a temperature between 160 - 180 °C, and the heat cannot be utilized, causing energy waste. In this device, during the startup stage, saturated steam from the saturated steam pipe network is transported to the heat preservation steam inlet 6 to preheat and keep warm the first-stage evaporator. The generated condensate is discharged through the heat preservation steam condensate outlet 7 to prevent the ammonium nitrate material from crystallizing due to low temperature after entering the first-stage evaporator. During the normal production stage, the first valve 11 is closed, and the saturated steam stops being continuously transported to the heat preservation steam inlet 6. The second regulating valve 12 is opened. The first-stage vacuum falling-film evaporator uses the high-temperature alkaline steam generated by the neutralization reaction from the neutralizer as a heat source and enters through the alkaline steam inlet 1. The condensate is discharged through the alkaline steam condensate outlet 5. The heat of the alkaline steam is used for vacuum falling-film evaporation of the dilute nitric acid solution, reducing the usage amount of saturated steam. At the same time, the energy of the high-temperature alkaline steam is utilized. The ammonium nitrate solution with a concentration of about 70 - 80% in terms of the properties of the ammonium nitrate solution will crystallize due to low temperature when the temperature is lower than 110 - 120 °C. Therefore, it is necessary to maintain the evaporation temperature. The alkaline steam is about 160 - 180 °C, and the ammonium nitrate solution is kept warm and heated by means of wall heat exchange to prevent crystallization.
[0030] Example 2
[0031] This embodiment is an improvement made to Example 1. Please refer to Figure 1 , specifically, the above-mentioned heating pipe 10 is spirally arranged at the bottom of the first-stage evaporator 9.
[0032] The above-mentioned heating pipe 10 is made of stainless steel pipe.
[0033] When carrying out heat recycling, the steam moves inside the heating pipe 10. Since the heating pipe 10 is made of stainless steel pipe with good heat dissipation, it can effectively carry out energy exchange. At the same time, the heating pipe 10 is spirally arranged. During the startup stage, saturated steam is used to preheat and keep warm the bottom of the first-stage evaporator 9 to prevent the ammonium nitrate material from crystallizing due to low temperature after entering the first-stage evaporator.
[0034] It should be noted that in this article, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the term "including", "comprising" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not expressly listed, or further includes elements inherent to such process, method, article or device.
[0035] Although embodiments of the present utility model have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principle and spirit of the present utility model. The scope of the present utility model is defined by the appended claims and their equivalents.
Claims
1. An energy-saving evaporator device for ammonium nitrate solution, characterized in that: It comprises a first-stage evaporator (9), a dilute ammonium nitrate solution inlet (2) and a concentrated ammonium nitrate solution outlet (5), The top of the first stage evaporator (9) is provided with a vertically arranged inlet (2) for a dilute ammonium nitrate solution, and the bottom of the first stage evaporator (9) is provided with an outlet (5) for a concentrated ammonium nitrate solution; An alkaline steam inlet (1) and an alkaline steam condensate outlet (3) are installed on the side of the first stage evaporator (9) in an upper and lower distribution, and a second regulating valve (12) is installed on the outer side of the external pipe of the alkaline steam inlet (1); A gas phase equilibrium port (8) connected to a first stage evaporator (9) is provided between the alkaline steam inlet (1) and the alkaline steam condensate outlet (3), and a gas phase condensate outlet (4) is installed on the other side of the first stage evaporator (9); A heating pipe (10) is fixedly connected to the outer side of the bottom of the first section of the evaporator (9), one end of the heating pipe (10) is fixedly connected to a heat preservation steam inlet (6), and the other end of the heating pipe (10) is fixedly connected to a heat preservation steam condensate outlet (7).
2. An energy-saving evaporator device for ammonium nitrate solution according to claim 1, characterized in that: The heating tube (10) is spirally arranged at the bottom of a section of the evaporator (9).
3. An energy-saving evaporator device for ammonium nitrate solution according to claim 1, characterized in that: The heating tube (10) is made of a stainless steel tube.
4. The energy-saving evaporator device for ammonium nitrate solution according to claim 1, characterized in that: A first regulating valve (11) is installed on the outside of the external pipe of the heat-insulating steam inlet (6).