A process for recovering nitric acid from octol residual liquor
By combining low-temperature evaporation and distillation, the problem of the residual liquid in Octogen exceeding the boiler's capacity was solved, achieving efficient recovery of nitrates and safe cost reduction.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- CHANGZHOU DDS ENVIRONMENTAL PROTECTION TECHCO
- Filing Date
- 2024-02-06
- Publication Date
- 2026-06-26
AI Technical Summary
In existing technologies, as production capacity expands, the amount of distillation residue from Octogen increases, exceeding the original boiler's processing capacity, leading to increased safety risks and processing costs.
A combination of low-temperature evaporation and distillation is used. Water is removed from the distillation residue by a low-temperature evaporator, diluent is added and stirred to crystallize ammonium nitrate, ammonium nitrate is separated by a solid-liquid separator, diluent is recovered by activated carbon, and the remaining waste liquid is incinerated in a reaction vessel.
It effectively reduced incineration operating costs, improved safety, achieved efficient recovery of nitrates, reduced diluent waste, and lowered safety risks.
Abstract
Description
Technical Field
[0001] This invention belongs to the field of waste liquid treatment and recycling technology, and particularly relates to a process for recovering nitrates from Octogen residue. Background Technology
[0002] Wastewater treatment includes wastewater incineration, organic wastewater treatment, or organic industrial wastewater treatment, also known as high-concentration organic wastewater treatment. Treatment methods include physical, chemical, and biological methods. Chemical treatment is often combined with physical processes, hence the term physicochemical treatment. Physical treatment refers to treating wastewater using physical or mechanical separation methods, commonly including filtration, sedimentation, flotation, oil separation, and centrifugation. Chemical treatment separates and removes dissolved or colloidal pollutants from wastewater or converts them into harmless substances through chemical reactions and mass transfer. Biological treatment utilizes the metabolic activity of microorganisms to transform organic pollutants in solution, colloidal, and finely suspended states in wastewater into stable, harmless substances.
[0003] The main components of octogen residue are ammonium nitrate, acetone, ethyl acetate, acetic acid, product byproducts, and trace product residues. The wastewater contains unstable components, posing certain safety risks. The wastewater has the following characteristics: 1. Contains unstable components, posing certain safety risks; 2. High TDS, poor fluidity after concentration, and easy precipitation of solids, affecting subsequent transportation and incineration, and easily causing instrument inlets to become clogged, leading to instrument inaccuracy; 3. High ammonia nitrogen / total nitrogen ratio, easily entering the condensate, increasing the difficulty of subsequent treatment. The current method for treating octogen residue involves distilling the residue and then co-firing the distillate in a boiler. However, with the expansion of production capacity, the amount of distillate residue also increases, exceeding the original boiler's processing capacity. To ensure that the final treatment process of incineration remains unchanged, a process for recovering nitrate from octogen residue is needed. Summary of the Invention
[0004] The purpose of this invention is to address the problem that the existing method of treating octogen residue involves distilling the octogen residue and then co-firing the distillate in a boiler. However, as production capacity increases, the amount of distillate residue also increases, exceeding the original boiler's processing capacity. Therefore, this invention proposes a process for recovering nitrates from octogen residue.
[0005] To achieve the above objectives, the present invention adopts the following technical solution:
[0006] A process for recovering nitrates from Octogen residue specifically includes the following steps:
[0007] S1. The generated wastewater is introduced into a distillation pot and distilled to produce distillation residue.
[0008] S2. Pour the distillation residue into the low-temperature evaporator and control the low-temperature evaporator to evaporate the distillation residue at a low temperature to remove excess water from the distillation residue. Finally, the distillation residue forms a thick slurry.
[0009] S3. Take out the thick slurry and add the thinner. Then stir the thick slurry to fully mix the thinner into the thick slurry.
[0010] S4. After the slurry cools down, the ammonium nitrate in the slurry gradually crystallizes.
[0011] S5. Pour the concentrated slurry into the solid-liquid separator and control the operation of the solid-liquid separator to achieve the purpose of separating the slurry and crystallized ammonium nitrate.
[0012] S6. Collect the separated slurry and take out the crystallized ammonium nitrate. Place the ammonium nitrate on gauze and then rinse it with clean water to dilute the diluent remaining on the surface of the ammonium nitrate. At the same time, non-salt organic matter attached to the surface of the ammonium nitrate will dissolve. Finally, the clean water used for rinsing will flow out through the gauze and be collected in a container.
[0013] S7. Collect the washed ammonium nitrate, dry it, and finally collect the dried ammonium nitrate in plastic bags.
[0014] S8. Pour the water used to wash the ammonium nitrate and the separated slurry into a container, and then introduce the mixed liquid into a distillation column for distillation to reduce the water content in the mixed liquid.
[0015] S9. Collect the remaining mixed liquid, pour the mixed liquid into the reactor for heating, then add activated carbon into the reactor. The activated carbon absorbs the diluent in the mixed liquid. Finally, remove the activated carbon to recover the diluent, and put the remaining waste liquid into the boiler for incineration.
[0016] As a further description of the above technical solution:
[0017] In step S1, the temperature of the distillation pot is controlled at 100℃-120℃, the distillation time is controlled at 2-3 hours, and the distillation residue produced after distillation has the following components: 25%-30% organic matter, salt, and 70%-75% water.
[0018] As a further description of the above technical solution:
[0019] In step S2, after evaporating the distillation residue using a low-temperature evaporator, 20%-25% of the water remains in the distillation residue. The distillation residue itself contains energetic materials, and the use of low-temperature evaporation can effectively avoid safety risks, greatly improving safety compared to conventional evaporation and concentration methods. In addition, controlling the proportion of residual water in the distillation residue is also one of the key factors for safe recycling.
[0020] As a further description of the above technical solution:
[0021] In step S3, the diluent includes the following components: methanol, ethanol, and acetic acid, which are organic solvents. The ratio of methanol, ethanol, and acetic acid is 2:2:1, and the content of methanol, ethanol, and acetic acid accounts for 5-15% of the total content of the concentrated slurry.
[0022] As a further description of the above technical solution:
[0023] In step S3, a mixer is used to stir the thick slurry, and the speed of the mixer is controlled at 300-500 rpm, and the stirring time is controlled at 3-5 min.
[0024] As a further description of the above technical solution:
[0025] In step S6, the ammonium nitrate is rinsed with clean water for 2-4 minutes. During the rinsing process, the gauze is shaken to adjust the position of the ammonium nitrate so that it can be thoroughly rinsed and the diluent adhering to the surface can be washed away.
[0026] As a further description of the above technical solution:
[0027] In step S7, the ammonium nitrate is dried by blowing air using a dryer for 10-15 minutes.
[0028] As a further description of the above technical solution:
[0029] In step S8, excess water in the mixed liquid is evaporated by distillation, and the diluent is also evaporated and collected under the action of distillation, so as to achieve the purpose of recovering the diluent, and only 20% of the mixed liquid remains.
[0030] As a further description of the above technical solution:
[0031] In step S9, indirect heating is controlled inside the reactor to ensure that the temperature inside the reactor is controlled at 50-60℃, and the activated carbon is left in the mixed liquid for 24-48 hours after being added.
[0032] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:
[0033] 1. In this invention, the residual liquid after distillation is further evaporated using a low-temperature evaporator. The resulting concentrated slurry has a significantly reduced internal moisture content, greatly reducing the operating cost of incineration. Furthermore, given the unstable factors contained in the distillation residual liquid, this invention maintains the distillation residual liquid at a low temperature throughout the process of evaporating and concentrating it, thus greatly improving safety.
[0034] 2. In this invention, the diluent in the mixed liquid is recovered for the first time by distillation, and then the remaining diluent is recovered for the second time by activated carbon. The dual recovery method greatly recovers the diluent and saves the cost of waste liquid treatment. Detailed Implementation
[0035] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention. Example
[0036] This invention provides a technical solution: a process for recovering nitrates from octogen residue, characterized by comprising the following steps:
[0037] S1. The generated wastewater is introduced into a distillation pot and distilled. The wastewater is distilled using the distillation pot. Distillation residue is generated after distillation. The temperature of the distillation pot is controlled at 100℃ and the distillation time is controlled at 2h. The distillation residue generated after distillation has the following components: 25% organic matter, salt, and 70% water.
[0038] S2. Pour the distillation residue into a low-temperature evaporator and control the low-temperature evaporator to evaporate the distillation residue at a low temperature to remove excess water. Finally, the distillation residue forms a thick slurry. After evaporating the distillation residue using the low-temperature evaporator, 20% of the water remains in the distillation residue.
[0039] S3. Take out the concentrated slurry and add diluent. Then stir the concentrated slurry to fully mix the diluent into the slurry. The diluent includes the following components: methanol, ethanol, and acetic acid, which are organic solvents. The addition ratio of methanol, ethanol, and acetic acid is 2:2:1. The content of methanol, ethanol, and acetic acid accounts for 5% of the total content of the concentrated slurry. Use a mixer to stir the concentrated slurry, control the speed of the mixer to 300 rpm, and control the stirring time to 3 minutes.
[0040] S4. After the slurry cools down, the ammonium nitrate in the slurry gradually crystallizes.
[0041] S5. Pour the concentrated slurry into the solid-liquid separator and control the operation of the solid-liquid separator to achieve the purpose of separating the slurry and crystallized ammonium nitrate.
[0042] S6. Collect the separated slurry and take out the crystallized ammonium nitrate. Place the ammonium nitrate on gauze and then rinse it with clean water to dilute the diluent remaining on the surface of the ammonium nitrate. At the same time, non-salt organic matter attached to the surface of the ammonium nitrate will dissolve. Finally, the clean water used for rinsing will flow out through the gauze. Collect the clean water used to wash the ammonium nitrate in a container and rinse the ammonium nitrate with clean water for 2 minutes. During the rinsing process, shake the gauze to adjust the position of the ammonium nitrate so that the ammonium nitrate can be thoroughly rinsed and the diluent attached to the surface can be washed away.
[0043] S7. Collect the cleaned ammonium nitrate, dry it, and finally collect the dried ammonium nitrate in a plastic bag. Use a dryer to dry the ammonium nitrate by blowing air for 10 minutes.
[0044] S8. Pour the water used to wash the ammonium nitrate and the separated slurry into a container. Then, introduce the mixed liquid into a distillation column for distillation to reduce the water content in the mixed liquid. The excess water in the mixed liquid is evaporated by distillation, and the diluent will also evaporate and be collected under the action of distillation, so as to achieve the purpose of recovering the diluent. Only 20% of the mixed liquid remains.
[0045] S9. Collect the remaining mixed liquid, pour the mixed liquid into the reactor for heating, then add activated carbon into the reactor. The activated carbon absorbs the diluent in the mixed liquid. Finally, remove the activated carbon to recover the diluent, and put the remaining waste liquid into the boiler for incineration. Control the indirect heating inside the reactor to ensure that the temperature inside the reactor is controlled at 50°C. After adding the activated carbon, leave it in the mixed liquid for 24 hours. Example
[0046] This invention provides a technical solution: a process for recovering nitrates from octogen residue, characterized by comprising the following steps:
[0047] S1. The generated wastewater is introduced into a distillation pot and distilled. The wastewater is distilled and distilled to produce distillate residue. The temperature of the distillation pot is controlled at 110℃ and the distillation time is controlled at 2.5h. The distillate residue produced after distillation has the following components: 28% organic matter, salt, and 73% water.
[0048] S2. Pour the distillation residue into a low-temperature evaporator and control the low-temperature evaporator to evaporate the distillation residue at a low temperature to remove excess water. Finally, the distillation residue forms a thick slurry. After evaporating the distillation residue using the low-temperature evaporator, 23% of the water remains in the distillation residue.
[0049] S3. Take out the concentrated slurry and add diluent. Then stir the concentrated slurry to ensure that the diluent is fully mixed in. The diluent includes the following components: methanol, ethanol, and acetic acid, which are organic solvents. The addition ratio of methanol, ethanol, and acetic acid is 2:2:1. The content of methanol, ethanol, and acetic acid accounts for 10% of the total content of the concentrated slurry. Use a mixer to stir the concentrated slurry, controlling the speed of the mixer at 400 rpm and the stirring time at 4 min.
[0050] S4. After the slurry cools down, the ammonium nitrate in the slurry gradually crystallizes.
[0051] S5. Pour the concentrated slurry into the solid-liquid separator and control the operation of the solid-liquid separator to achieve the purpose of separating the slurry and crystallized ammonium nitrate.
[0052] S6. Collect the separated slurry and take out the crystallized ammonium nitrate. Place the ammonium nitrate on gauze and then rinse it with clean water to dilute the diluent remaining on the surface of the ammonium nitrate. At the same time, non-salt organic matter attached to the surface of the ammonium nitrate will dissolve. Finally, the clean water used for rinsing will flow out through the gauze. Collect the clean water used to wash the ammonium nitrate in a container and rinse the ammonium nitrate with clean water for 3 minutes. During the rinsing process, shake the gauze to adjust the position of the ammonium nitrate so that the ammonium nitrate can be thoroughly rinsed and the diluent attached to the surface can be washed away.
[0053] S7. Collect the cleaned ammonium nitrate, dry it, and finally collect the dried ammonium nitrate in a plastic bag. Use a dryer to dry the ammonium nitrate by blowing air for 13 minutes.
[0054] S8. Pour the water used to wash the ammonium nitrate and the separated slurry into a container. Then, introduce the mixed liquid into a distillation column for distillation to reduce the water content in the mixed liquid. The excess water in the mixed liquid is evaporated by distillation, and the diluent will also evaporate and be collected under the action of distillation, so as to achieve the purpose of recovering the diluent. Only 20% of the mixed liquid remains.
[0055] S9. Collect the remaining mixed liquid, pour the mixed liquid into the reactor for heating, then add activated carbon into the reactor. The activated carbon absorbs the diluent in the mixed liquid. Finally, remove the activated carbon to recover the diluent, and put the remaining waste liquid into the boiler for incineration. Control the indirect heating inside the reactor to ensure that the temperature inside the reactor is controlled at 55°C. After adding the activated carbon, leave it in the mixed liquid for 36 hours. Example
[0056] This invention provides a technical solution: a process for recovering nitrates from octogen residue, characterized by comprising the following steps:
[0057] S1. The generated wastewater is introduced into a distillation pot and distilled. The wastewater is distilled to produce distillate residue. The temperature of the distillation pot is controlled at 120℃ and the distillation time is controlled at 3h. The distillate residue produced after distillation has the following components: 30% organic matter, salt, and 75% water.
[0058] S2. Pour the distillation residue into a low-temperature evaporator and control the low-temperature evaporator to evaporate the distillation residue at a low temperature to remove excess water. Finally, the distillation residue forms a thick slurry. After evaporating the distillation residue using the low-temperature evaporator, 25% of the water remains in the distillation residue.
[0059] S3. Take out the concentrated slurry and add diluent. Then stir the concentrated slurry to fully mix the diluent into the slurry. The diluent includes the following components: methanol, ethanol, and acetic acid, which are organic solvents. The addition ratio of methanol, ethanol, and acetic acid is 2:2:1. The content of methanol, ethanol, and acetic acid accounts for 15% of the total content of the concentrated slurry. Use a mixer to stir the concentrated slurry, control the speed of the mixer to 500 rpm, and control the stirring time to 5 minutes.
[0060] S4. After the slurry cools down, the ammonium nitrate in the slurry gradually crystallizes.
[0061] S5. Pour the concentrated slurry into the solid-liquid separator and control the operation of the solid-liquid separator to achieve the purpose of separating the slurry and crystallized ammonium nitrate.
[0062] S6. Collect the separated slurry and take out the crystallized ammonium nitrate. Place the ammonium nitrate on gauze and then rinse it with clean water to dilute the diluent remaining on the surface of the ammonium nitrate. At the same time, non-salt organic matter attached to the surface of the ammonium nitrate will dissolve. Finally, the clean water used for rinsing will flow out through the gauze. Collect the clean water used to wash the ammonium nitrate in a container and rinse the ammonium nitrate with clean water for 4 minutes. During the rinsing process, shake the gauze to adjust the position of the ammonium nitrate so that the ammonium nitrate can be thoroughly rinsed and the diluent attached to the surface can be washed away.
[0063] S7. Collect the cleaned ammonium nitrate, dry it, and finally collect the dried ammonium nitrate in a plastic bag. Use a dryer to dry the ammonium nitrate by blowing air for 15 minutes.
[0064] S8. Pour the water used to wash the ammonium nitrate and the separated slurry into a container. Then, introduce the mixed liquid into a distillation column for distillation to reduce the water content in the mixed liquid. The excess water in the mixed liquid is evaporated by distillation, and the diluent will also evaporate and be collected under the action of distillation, so as to achieve the purpose of recovering the diluent. Only 20% of the mixed liquid remains.
[0065] S9. Collect the remaining mixed liquid, pour the mixed liquid into the reactor for heating, then add activated carbon into the reactor. The activated carbon absorbs the diluent in the mixed liquid. Finally, remove the activated carbon to recover the diluent, and put the remaining waste liquid into the boiler for incineration. Control the indirect heating inside the reactor to ensure that the temperature inside the reactor is controlled at 60℃. After adding the activated carbon, leave it in the mixed liquid for 48 hours.
[0066] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.
Claims
1. A process for recovering nitrates from Octogen residue, characterized in that, Specifically, the following steps are included: S1. The generated wastewater is introduced into a distillation pot and distilled to produce distillation residue. S2. Pour the distillation residue into the low-temperature evaporator and control the low-temperature evaporator to evaporate the distillation residue at a low temperature to remove excess water from the distillation residue. The water content in the distillation residue will be 20%-25%, and the distillation residue will finally form a thick slurry. S3. Take out the thick slurry and add the thinner. Then stir the thick slurry to fully mix the thinner into the thick slurry. S4. After the slurry cools down, the ammonium nitrate in the slurry gradually crystallizes. S5. Pour the concentrated slurry into the solid-liquid separator and control the operation of the solid-liquid separator to achieve the purpose of separating the slurry and crystallized ammonium nitrate. S6. Collect the separated slurry and take out the crystallized ammonium nitrate. Place the ammonium nitrate on gauze and then rinse it with clean water to dilute the diluent remaining on the surface of the ammonium nitrate. At the same time, non-salt organic matter attached to the surface of the ammonium nitrate will dissolve. Finally, the clean water used for rinsing will flow out through the gauze and be collected in a container. S7. Collect the washed ammonium nitrate, dry it, and finally collect the dried ammonium nitrate in plastic bags. S8. Pour the water used to wash the ammonium nitrate and the separated slurry into a container, and then introduce the mixed liquid into a distillation column for distillation to reduce the water content in the mixed liquid. S9. Collect the remaining mixed liquid, pour the mixed liquid into the reactor for heating, then add activated carbon into the reactor. The activated carbon absorbs the diluent in the mixed liquid. Finally, remove the activated carbon to recover the diluent, and put the remaining waste liquid into the boiler for incineration.
2. The process for recovering nitrate from Octogen residue according to claim 1, characterized in that, In step S1, the temperature of the distillation pot is controlled at 100℃-120℃, the distillation time is controlled at 2-3 hours, and the distillation residue produced after distillation has the following components: 25%-30% organic matter, salt, and 70%-75% water.
3. The process for recovering nitrate from Octogen residue according to claim 1, characterized in that, In step S3, the diluent includes the following components: methanol, ethanol, and acetic acid, which are organic solvents. The ratio of methanol, ethanol, and acetic acid is 2:2:1, and the content of methanol, ethanol, and acetic acid accounts for 5-15% of the total content of the concentrated slurry.
4. The process for recovering nitrate from Octogen residue according to claim 1, characterized in that, In step S3, a mixer is used to stir the thick slurry, and the speed of the mixer is controlled at 300-500 rpm, and the stirring time is controlled at 3-5 min.
5. The process for recovering nitrate from Octogen residue according to claim 1, characterized in that, In step S6, the ammonium nitrate is rinsed with clean water for 2-4 minutes. During the rinsing process, the gauze is shaken to adjust the position of the ammonium nitrate so that it can be thoroughly rinsed and the diluent adhering to the surface can be washed away.
6. The process for recovering nitrate from Octogen residue according to claim 1, characterized in that, In step S7, the ammonium nitrate is dried by blowing air using a dryer for 10-15 minutes.
7. The process for recovering nitrate from Octogen residue according to claim 1, characterized in that, In step S8, excess water in the mixed liquid is evaporated by distillation, and the diluent is also evaporated and collected under the action of distillation, so as to achieve the purpose of recovering the diluent, and only 20% of the mixed liquid remains.
8. The process for recovering nitrate from Octogen residue according to claim 1, characterized in that, In step S9, indirect heating is controlled inside the reactor to ensure that the temperature inside the reactor is controlled at 50-60℃, and the activated carbon is left in the mixed liquid for 24-48 hours after being added.