A continuous evaporation apparatus and method for sodium formate

Abstract

This invention provides a continuous evaporation apparatus and method for sodium formate, relating to the field of chemical purification. The apparatus is used to process a mixture of formaldehyde removal liquid and mother liquor, and to continuously produce sodium formate. The apparatus includes: an evaporation component comprising multiple evaporators connected in series; and a crystallization separation device, the inlet of which is connected to the bottom outlet of the evaporation component, for crystallizing and separating the concentrated material from the solid liquid. The continuous evaporation apparatus for sodium formate provided in this embodiment of the invention, by setting up an evaporation component including multiple evaporators connected in series, and a crystallization separation device connected to the evaporation component, can continuously evaporate, concentrate, and crystallize the mixture of formaldehyde removal liquid and mother liquor.

Description

Technical Field

[0001] This invention relates to the field of chemical purification, and in particular to a continuous evaporation apparatus and method for sodium formate. Background Technology

[0002] In the production of sodium formate, the mixture of formaldehyde removal liquid and mother liquor needs to be evaporated and concentrated, and then separated by crystallization to obtain the sodium formate product. Currently, most existing sodium formate evaporation devices adopt a single-stage evaporator structure. Single-stage evaporators are difficult to concentrate the material to a suitable crystallization state, resulting in low evaporation efficiency, which cannot meet the needs of continuous sodium formate production. Summary of the Invention

[0003] This invention provides a continuous evaporation apparatus and method for sodium formate, used to concentrate sodium formate material to achieve a suitable crystallization state, improve evaporation efficiency, and meet the needs of continuous production.

[0004] This invention provides a continuous sodium formate evaporation apparatus for processing a mixture of formaldehyde removal liquid and mother liquor, and continuously producing sodium formate product. The apparatus includes: Evaporation assembly, including multi-stage evaporators connected in series; The crystallization separation device has its inlet connected to the bottom outlet of the evaporation assembly and is used for crystallization and solid-liquid separation of concentrated materials. in, The first-stage evaporator of the evaporation assembly introduces a mixture of formaldehyde removal liquid and mother liquor through a pipeline, and its material outlet is connected to the next-stage evaporator. The material outlet of the last-stage evaporator of the evaporation assembly is connected to a crystallization separation device.

[0005] In some embodiments, the primary evaporator is provided with a secondary steam inlet for the formaldehyde removal tower and an auxiliary steam inlet for heating and evaporating the formaldehyde removal liquid and the mother liquor.

[0006] In some embodiments, the secondary steam inlet of the formaldehyde removal tower is connected to the heating inlet of the next-stage evaporator to provide a heat source.

[0007] In some embodiments, the final stage evaporator is further provided with a formaldehyde removal tower flash steam inlet for heating using formaldehyde removal tower flash steam.

[0008] In some embodiments, the final stage evaporator further includes a steam outlet connected to a vacuum system for condensing the generated water vapor.

[0009] A second aspect of this invention provides a continuous evaporation method for sodium formate, the continuous evaporation method for sodium formate being implemented based on the aforementioned continuous evaporation device for sodium formate, the continuous evaporation device for sodium formate further including a feed pump, a delivery pump, a steam valve, a discharge valve, a temperature sensor, and a liquid level sensor; The feed pump is controlled to send the mixture of formaldehyde removal liquid and mother liquor into the evaporation assembly, where the mixture of formaldehyde removal liquid and mother liquor is continuously evaporated in the first-stage evaporator of the evaporation assembly; The temperature of the steam received in the first-stage evaporator is obtained by a temperature sensor. When the temperature rises to the evaporation temperature threshold, the opening of the steam valve is controlled to evaporate and concentrate the mixture of formaldehyde removal liquid and mother liquor. The temperature of the steam received in the first-stage evaporator is obtained by a temperature sensor. When the temperature rises to the evaporation temperature threshold, the opening of the steam valve is controlled to evaporate and concentrate the material entering the next-stage evaporator. The temperature of the material in the final stage evaporator is obtained by a temperature sensor. When the temperature reaches the temperature threshold, the discharge valve in the final stage evaporator is opened to discharge the material to the crystallization separation system. The solid obtained by separation is sodium formate.

[0010] In some embodiments, the sodium formate continuous evaporation apparatus further includes a feed valve and a liquid level sensor; The temperature of the material inside the final stage evaporator is obtained by a temperature sensor, and when the temperature reaches a temperature threshold, the discharge valve in the final stage evaporator is opened, including: The liquid level in the final stage evaporator is obtained by a liquid level sensor. When the liquid level reaches the feed threshold, the opening of the feed valve is controlled to keep the material continuously and stably transported to the sodium formate crystallization separation system.

[0011] In some embodiments, the sodium formate continuous evaporation apparatus further includes a feed valve, a temperature sensor, and a delivery pump; The temperature of the material inside the final stage evaporator is obtained by a temperature sensor, and when the temperature reaches a temperature threshold, the discharge valve in the final stage evaporator is opened, including: The heating temperature of the multi-stage evaporator is obtained by a temperature sensor. When the temperature reaches the evaporation threshold, the delivery pump is controlled to run, and the material is continuously evaporated and concentrated through the multi-stage evaporator.

[0012] In some embodiments, the sodium formate continuous evaporation apparatus further includes a level sensor and a transfer pump; The temperature of the material inside the final stage evaporator is obtained by a temperature sensor, and when the temperature reaches a temperature threshold, the discharge valve in the final stage evaporator is opened, including: The liquid level of the material in the crystallization separation system is obtained by a liquid level sensor. When the liquid level reaches the separation threshold, the transfer pump is controlled to start, and the sodium formate product is continuously output.

[0013] In some embodiments, the sodium formate continuous evaporation apparatus further includes a vacuum device and a pressure sensor; The temperature of the material inside the final stage evaporator is obtained by a temperature sensor. When the temperature reaches a temperature threshold, controlling the opening of the discharge valve in the final stage evaporator includes: The evaporation pressure of the final stage evaporator is obtained by a pressure sensor. When the pressure reaches a threshold, the vacuum device is activated to condense the water vapor generated by the final stage evaporator.

[0014] Beneficial effects: The sodium formate continuous evaporation apparatus provided in this embodiment of the invention, by setting up an evaporation assembly including a multi-stage series evaporator and a crystallization separation device connected to the evaporation assembly, can continuously evaporate, concentrate and crystallize the mixture of formaldehyde removal liquid and mother liquor. Multi-stage evaporators can perform step-by-step evaporation of materials, which helps to improve the concentration effect and adapt to the needs of continuous production. The layout of feeding into the first-stage evaporator and discharging into the last-stage evaporator allows the materials to complete the evaporation process in an orderly manner, which helps to improve the stability of the unit's operation and simplifies the material conveying path. By combining multi-stage evaporation with crystallization separation, the continuous production of sodium formate can be completed relatively smoothly, which helps to improve production efficiency and also helps to improve the problems of unstable operation that are prone to occur in traditional evaporation methods. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the combined structure of the evaporation assembly, vacuum system, and crystallization separation device provided in an embodiment of the present invention; Figure 2 A schematic flowchart of a continuous evaporation method for sodium formate provided in an embodiment of the present invention; Figure 3 A schematic flowchart of the first continuous evaporation method for sodium formate provided in an embodiment of the present invention; Figure 4 This is a schematic flowchart of a second continuous evaporation method for sodium formate provided in an embodiment of the present invention; Figure 5 This is a schematic flowchart of the third continuous evaporation method for sodium formate provided in an embodiment of the present invention; Figure 6 This is a schematic flowchart of the fourth continuous evaporation method for sodium formate provided in an embodiment of the present invention.

[0016] Explanation of reference numerals in the attached figures: 1. Evaporation assembly; 2. Vacuum system; 3. Flash steam inlet of the formaldehyde removal tower; 4. Crystallization separation device; 5. Auxiliary steam inlet; 6. Secondary steam inlet of the formaldehyde removal tower; 7. Mixture of formaldehyde removal liquid and mother liquor. Detailed Implementation

[0017] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0018] The specific technical features described in the various embodiments in the detailed implementation can be combined in various ways without contradiction. For example, different implementation methods can be formed by combining different specific technical features. In order to avoid unnecessary repetition, the various possible combinations of the specific technical features in this invention will not be described separately.

[0019] It should also be noted that, in order to avoid obscuring the invention with unnecessary details, only the structures and / or processing steps closely related to the present invention are shown in the accompanying drawings, while other details that are not closely related to the present invention are omitted.

[0020] Additionally, it should be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. In the following description, the terms "first," "second," etc., are used merely to distinguish different objects and do not indicate any similarity or connection between them. It should be understood that the directional descriptions such as "above," "below," "inside," and "outside" refer to the orientation under normal use conditions.

[0021] In the following specific embodiments, the sodium formate continuous evaporation device can be applied to various sodium formate production systems. For example, the device can be applied to a pentaerythritol-sodium formate co-production system for continuously processing the mixture 7 of the dealdehyde liquid and mother liquor generated in the reaction to prepare sodium formate product. For example, the device can also be applied to a purification and concentration system for chemically synthesized crude sodium formate for continuous evaporation and crystallization separation of the sodium formate feed solution. The structure and operation of the device are illustrated below using the application of this sodium formate continuous evaporation device in a pentaerythritol-sodium formate co-production system as an example.

[0022] In some embodiments, such as Figure 1As shown, the sodium formate continuous evaporation device includes: an evaporation assembly 1 and a crystallization separation device 4. The evaporation assembly 1 is equipped with multiple evaporators connected in series. The evaporation assembly 1 is used to continuously heat, evaporate, and concentrate the mixture 7 of the formaldehyde removal liquid and the mother liquor to increase the solid content of the material. The inlet of the crystallization separation device 4 is connected to the bottom outlet of the evaporation assembly 1. The crystallization separation device 4 is used to cool and crystallize the evaporated and concentrated material and to separate the solid and liquid components to obtain the sodium formate solid product.

[0023] The first-stage evaporator of the evaporation assembly 1 is connected to the mixture of formaldehyde removal liquid and mother liquor 7 via a pipeline. The material outlet of the first-stage evaporator is connected to the next-stage evaporator, so that the material can be transported and evaporated and concentrated in the multi-stage evaporators in sequence. The material outlet of the last-stage evaporator of the evaporation assembly 1 is connected to the crystallization separation device 4. The material after multi-stage evaporation and concentration can be stably transported to the crystallization separation device 4 for subsequent processing.

[0024] It can be understood that, due to the limitations of sodium formate production process and equipment layout, using a single-stage evaporator for evaporation and concentration usually makes it difficult to achieve the ideal concentration state of the material, and the evaporation efficiency is difficult to meet the needs of continuous production. By setting up multi-stage evaporators in series, the material can be evaporated and concentrated step by step, which helps to improve the uniformity of material concentration and also helps to improve the continuity of the overall evaporation process.

[0025] The first-stage evaporator, serving as the initial evaporation unit for material feeding, performs preliminary evaporation of the mixture of formaldehyde-removing liquid and mother liquor 7, removing some moisture. The next-stage evaporator further evaporates the pre-concentrated material, gradually increasing its concentration. The final-stage evaporator concentrates the material to a suitable state for crystallization, providing a better material basis for subsequent crystallization and separation. The interconnected layout of multiple evaporators allows for continuous material transport and evaporation within the unit, reducing material transfer points and improving the overall smoothness of sodium formate production.

[0026] In other words, the evaporation assembly 1 adopts a multi-stage series configuration, allowing the material to be gradually evaporated during the flow process. This helps improve the evaporation effect and maintain the stability of the unit's operation. Simultaneously, the final-stage evaporator is directly connected to the crystallization separation unit 4, enabling timely delivery of the concentrated material to the crystallization process. This helps reduce material residence time and, to some extent, ensures the quality of the sodium formate product.

[0027] The sodium formate continuous evaporation apparatus provided in this embodiment of the invention, by setting up an evaporation assembly 1 including a multi-stage series evaporator and a crystallization separation device 4 connected to the evaporation assembly 1, can continuously evaporate, concentrate and crystallize the mixture 7 of the formaldehyde removal liquid and the mother liquor.

[0028] Multi-stage evaporators connected in series can perform step-by-step evaporation of materials, which helps improve the concentration effect and adapts to the needs of continuous production. The layout of feeding into the first-stage evaporator and discharging into the last-stage evaporator allows the materials to complete the evaporation process in an orderly manner, which helps improve the stability of the unit's operation and simplifies the material conveying path. By combining multi-stage evaporation with crystallization separation, the continuous production of sodium formate can be completed relatively smoothly, which helps improve production efficiency and also helps to improve the unstable operation problems that are prone to occur in traditional evaporation methods.

[0029] In some embodiments, such as Figure 1 As shown, the primary evaporator is equipped with a secondary steam inlet 6 for the formaldehyde removal tower and an auxiliary steam inlet 5. The secondary steam inlet 6 and the auxiliary steam inlet 5 are used to introduce the corresponding heating medium into the primary evaporator to heat and evaporate the mixture 7 of the formaldehyde removal liquid and the mother liquor.

[0030] Optionally, the secondary steam inlet 6 of the formaldehyde removal tower is located at the lower part of the first-stage evaporator, and the auxiliary steam inlet 5 is located on the side of the first-stage evaporator. The two steam inlets are set independently and can supply heat to the interior of the first-stage evaporator separately or simultaneously.

[0031] Optionally, the secondary steam inlet 6 of the formaldehyde removal tower is connected to the steam outlet of the external formaldehyde removal tower to recover and utilize the secondary steam generated by the formaldehyde removal tower; the auxiliary steam inlet 5 is connected to the external steam pipeline network to supplement heat when the steam volume is insufficient, so as to make the heating state of the first-stage evaporator more stable.

[0032] Understandably, if only a single heat source is used for heating during the operation of the sodium formate continuous evaporation unit, large fluctuations in heat supply are likely to occur, which may affect the stability of material evaporation. However, by setting up a secondary steam inlet 6 and an auxiliary steam inlet 5 for the formaldehyde removal tower, multiple heat sources can be provided for the primary evaporator, which helps to maintain a stable evaporation temperature to a certain extent.

[0033] Optionally, both the secondary steam inlet 6 and the auxiliary steam inlet 5 of the formaldehyde removal tower are equipped with valves with adjustable opening. The steam flow rate can be adjusted according to the evaporation state of the material, so that the heating intensity in the first-stage evaporator is matched with the material processing capacity, which helps to improve the evaporation and concentration effect.

[0034] It can be understood that the secondary steam from the formaldehyde removal tower is a process waste heat. Introducing it into the first-stage evaporator for utilization can help reduce the overall system's energy consumption to a certain extent. The auxiliary steam can serve as a backup and supplementary heat source, which can reduce the situation of unstable evaporation caused by insufficient supply of secondary steam from the formaldehyde removal tower, and make the continuous operation of the first-stage evaporator more reliable.

[0035] In some embodiments, such as Figure 1As shown, the secondary steam generated by the first-stage evaporator is connected to the heating inlet of the next-stage evaporator. The heating inlet of the next-stage evaporator is used to receive the secondary steam from the first-stage evaporator and to heat the material inside the next-stage evaporator. The following is an example illustration of a combination of a first-stage evaporator and a next-stage evaporator. Optionally, the secondary steam outlet of the first-stage evaporator is connected to the heating inlet of the next-stage evaporator via a steam pipeline. The steam pipeline is used to provide a flow channel for the secondary steam, allowing it to enter the next-stage evaporator more smoothly.

[0036] Understandably, during the operation of the sodium formate continuous evaporation unit, the secondary steam generated by the first-stage evaporator still has a certain amount of heat. Direct discharge of this secondary steam can easily cause energy loss. By connecting this part of the secondary steam to the heating inlet of the next-stage evaporator, the waste heat can be recovered and utilized, which helps to reduce the overall energy consumption of the system.

[0037] Meanwhile, after the secondary steam is introduced into the next stage evaporator, it can work with other heat sources to heat the material, which helps to improve the stability of the heating process, reduce temperature fluctuations caused by a single heat source, and also helps to improve the continuity of material evaporation in stages.

[0038] Optionally, a control component is provided in the flow path of the secondary steam. The control component can adjust the steam flow rate so as to adjust the heating intensity according to the evaporation requirements of the next stage evaporator, so that the evaporation process is more in line with the concentration requirements of the material.

[0039] In some embodiments, the final stage evaporator is further provided with a formaldehyde removal tower flash vapor inlet 3, which is used to introduce flash vapor generated by the external formaldehyde removal tower into the interior of the final stage evaporator, thereby providing auxiliary heating for the material in the final stage evaporator.

[0040] Optionally, the flash vapor inlet 3 of the formaldehyde removal tower corresponds to the heating chamber of the final stage evaporator. The flash vapor can enter the interior of the final stage evaporator along a preset channel without obstructing the flow of the flash vapor, thereby reducing the risk of interference during flash vapor transport.

[0041] Moreover, the flash steam inlet 3 of the formaldehyde removal tower can provide a stable access space for flash steam. For example, after the flash steam of the formaldehyde removal tower is introduced into the final stage evaporator through this inlet, the heat carried by the flash steam can be applied to the material, which can further improve the overall heating effect.

[0042] Specifically, by setting the formaldehyde removal tower flash steam inlet 3 in the final stage evaporator, the waste heat generated by the formaldehyde removal tower can be fully utilized, which helps to supplement the heating energy to a certain extent and also helps to maintain the relative stability of the evaporation temperature in the final stage evaporator.

[0043] In some embodiments, the final stage evaporator further includes a steam outlet connected to a vacuum system 2. The steam outlet and the vacuum system 2 are connected through a condensation pipe. The water vapor generated by evaporation in the final stage evaporator can enter the vacuum system 2 through the steam outlet, and the vacuum system 2 will condense the water vapor.

[0044] Optionally, the steam outlet is located at the top of the final stage evaporator and is directly connected to the evaporation space inside the final stage evaporator. Water vapor can rise naturally and be discharged through the steam outlet without obstructing the discharge of water vapor, thereby reducing the risk of water vapor accumulating in the final stage evaporator.

[0045] Furthermore, since the steam outlet is located at the top of the final stage evaporator, the water vapor can be drawn out from the steam outlet of the final stage evaporator and sent into the vacuum system 2, which can quickly condense the water vapor and prevent the condensed water from flowing back into the final stage evaporator, thus facilitating the maintenance of stable material concentration in the final stage evaporator.

[0046] If water vapor cannot be discharged in time during the operation of the final stage evaporator, it will easily lead to an increase in pressure inside the evaporator, which will affect the evaporation efficiency. By setting a steam outlet and connecting it to the vacuum system 2, water vapor can be discharged and condensed in time, which helps to maintain the negative pressure environment inside the final stage evaporator to a certain extent and also helps to ensure the continuity of the evaporation process.

[0047] This invention also provides a method for continuous evaporation of sodium formate, which is applied as shown in the accompanying drawings. Figure 1 The sodium formate continuous evaporation apparatus shown can be understood as the control unit of the sodium formate continuous evaporation apparatus. The process of the method is illustrated below with reference to various embodiments.

[0048] In some embodiments, the continuous evaporation method for sodium formate is implemented based on a continuous evaporation apparatus for sodium formate, which further includes a feed pump, a transfer pump, a steam valve, a discharge valve, a temperature sensor, and a liquid level sensor; such as Figure 2 As shown, the main steps of the continuous evaporation method for sodium formate include: Step S101: Control the feed pump to send the formaldehyde removal liquid and mother liquor mixture 7 into the evaporation component 1. The formaldehyde removal liquid and mother liquor mixture 7 is continuously evaporated in the first-stage evaporator in the evaporation component 1. This can be understood as follows: the staff first mixes the formaldehyde removal liquid and the mother liquor to form a mixture, and then controls the feed pump to operate. The feed pump delivers this mixture to evaporation unit 1, where it first enters the primary evaporator. At the same time, the heating structure starts working, heating the primary evaporator and causing the mixture to evaporate continuously inside.

[0049] The flow rate of the mixture can be controlled by the running time of the feed pump, or by installing a flow sensor on the feed pipeline and controlling the feed rate through the feedback of the flow sensor; the heating temperature of the evaporation component 1 can be controlled by the opening degree of the steam valve, or by installing a temperature sensor in the first-stage evaporator and controlling the heating intensity through the feedback of the temperature sensor.

[0050] Step S102: The temperature of the steam received in the first-stage evaporator is obtained by the temperature sensor. When the temperature rises to the evaporation temperature threshold, the opening of the steam valve is controlled to evaporate and concentrate the mixture 7 of the formaldehyde removal liquid and the mother liquor. This can be understood as a temperature sensor detecting the temperature of the steam received in the first-stage evaporator. When this temperature rises to the set evaporation temperature, it controls the opening and closing of the steam valve. This allows for the evaporation and concentration of the mixture of formaldehyde-removing liquid and mother liquor.

[0051] Step S103: The temperature of the steam received in the first-stage evaporator is obtained by the temperature sensor. When the temperature rises to the evaporation temperature threshold, the opening of the steam valve is controlled to evaporate and concentrate the material entering the next stage evaporator. Understandably, the temperature sensor continues to monitor the temperature of the steam received in the first-stage evaporator. Once this temperature rises back to the set evaporation temperature, the steam valve's opening and closing is controlled. This allows the material entering the next stage evaporator to continue evaporating and concentrating.

[0052] Step S104: The temperature of the material in the final stage evaporator is obtained by the temperature sensor. When the temperature reaches the temperature threshold, the discharge valve in the final stage evaporator is opened to discharge the material to the crystallization separation device. The solid obtained by separation is sodium formate product.

[0053] This can be understood as using a temperature sensor to detect the temperature of the material in the final stage evaporator. When this temperature reaches the set value, the discharge valve on the final stage evaporator is opened. The material is then discharged through the discharge valve and sent to the crystallization separation unit. After processing by the crystallization separation unit, the separated solid is the sodium formate product.

[0054] In some embodiments, the sodium formate continuous evaporation apparatus further includes a feed valve and a level sensor; such as Figure 3 As shown, with Figure 2 The difference is, Figure 3 Step S104 includes: Step S201: The liquid level of the material in the final stage evaporator is obtained by the liquid level sensor. When the liquid level reaches the feeding threshold, the opening of the feeding valve is controlled to keep the material continuously and stably transported to the sodium formate crystallization separation device.

[0055] This can be understood as follows: when the temperature of the material in the final stage evaporator is detected by a temperature sensor and reaches the set temperature threshold, the discharge valve of the final stage evaporator needs to be opened to transport the material to the crystallization separation device.

[0056] During this process, a liquid level sensor is used to obtain the material liquid level in the final stage evaporator in real time. When the detected liquid level reaches the set feed threshold, the opening of the feed valve is adjusted to allow the material to be continuously and stably delivered to the crystallization separation unit. During delivery, the material is transported more smoothly, avoiding material interruption or accumulation, and ensuring the smooth operation of subsequent crystallization separation processes. This makes the entire sodium formate production process smoother and reduces potential failures during production.

[0057] In some embodiments, the sodium formate continuous evaporation apparatus further includes a feed valve, a temperature sensor, and a delivery pump; such as Figure 4 As shown, with Figure 3 The difference is, Figure 4 Step S104 includes: Step S301: The heating temperature of the multi-stage evaporator is obtained by the temperature sensor. When the temperature reaches the evaporation threshold, the delivery pump is controlled to run, and the material is continuously evaporated and concentrated through the multi-stage evaporator.

[0058] It can be understood that the sodium formate continuous evaporation unit is also equipped with a feed valve, temperature sensor and delivery pump to help complete the continuous evaporation process of the material; When the heating temperature detected by the temperature sensor reaches the preset evaporation threshold, we control the transfer pump to start operating. Once the transfer pump is running, it sequentially delivers the material to each evaporator, allowing the material to gradually complete evaporation and concentration in different evaporators. The advantages of this approach are that it makes the evaporation process more continuous, reducing material accumulation or incomplete processing, and also ensuring that the heating effect of each stage of the evaporator is fully utilized, thereby improving overall evaporation efficiency and reducing energy waste. Furthermore, real-time monitoring by the temperature sensor and control of the transfer pump improve the efficiency of material conversion.

[0059] In some embodiments, the sodium formate continuous evaporation apparatus further includes a level sensor and a delivery pump; like Figure 5 As shown, with Figure 4 The difference is, Figure 5 Step S104 includes: Step S401: The liquid level of the material in the crystallization separation device 4 is obtained by the liquid level sensor. When the liquid level reaches the separation threshold, the transfer pump is turned on to continuously output the sodium formate product.

[0060] This can be understood as follows: the liquid level sensor obtains the liquid level of the material in the crystallization separation device 4. Once the material reaches the separation threshold, the sodium formate product produced can be output by controlling the delivery pump. This makes the entire process more seamless, stabilizes subsequent crystallization and separation processes, and reduces material accumulation.

[0061] In some embodiments, the sodium formate continuous evaporation apparatus further includes a vacuum device and a pressure sensor; like Figure 6 As shown, with Figure 5 The difference is, Figure 6 Step S104 includes: Step S501: Obtain the evaporation pressure of the final stage evaporator using a pressure sensor. When the pressure reaches the threshold, start the vacuum device to condense the water vapor generated by the final stage evaporator.

[0062] It can be understood that the staff controls the feed pump to send the mixture 7 of formaldehyde removal liquid and mother liquor into the evaporation component 1, and the material is heated and evaporated in the multi-stage evaporator in sequence.

[0063] Temperature sensors detect the temperature of the material inside the final stage evaporator. When the temperature reaches the set threshold, the operator controls the discharge valve of the final stage evaporator to open.

[0064] At this point, the pressure sensor detects the evaporation pressure inside the final stage evaporator. When the detected pressure reaches a set threshold, the system activates the vacuum device. After the vacuum device is running, it condenses the water vapor generated by the final stage evaporator and discharges it through the condensate pipe, keeping the internal pressure of the final stage evaporator within a suitable range and reducing the occurrence of steam overflow.

[0065] The above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention.

Claims

1. A continuous evaporation apparatus for sodium formate, characterized in that, The apparatus is used to process a mixture of formaldehyde removal liquid and mother liquor, and to continuously produce sodium formate. The apparatus includes: Evaporation assembly, including multi-stage evaporators connected in series; The crystallization separation device has its inlet connected to the bottom outlet of the evaporation assembly and is used for crystallization and solid-liquid separation of concentrated materials. in, The first-stage evaporator of the evaporation assembly introduces a mixture of formaldehyde removal liquid and mother liquor through a pipeline, and its material outlet is connected to the next-stage evaporator. The material outlet of the last-stage evaporator of the evaporation assembly is connected to a crystallization separation device.

2. The sodium formate continuous evaporation apparatus according to claim 1, characterized in that, The primary evaporator is equipped with a secondary steam inlet and an auxiliary steam inlet for heating and evaporating the formaldehyde removal liquid and mother liquor.

3. The sodium formate continuous evaporation apparatus according to claim 2, characterized in that, The secondary steam inlet of the formaldehyde removal tower is connected to the heating inlet of the next-stage evaporator to provide a heat source.

4. The sodium formate continuous evaporation apparatus according to claim 1, characterized in that, The final stage evaporator is also equipped with a formaldehyde removal tower flash steam inlet for heating using formaldehyde removal tower flash steam.

5. The sodium formate continuous evaporation apparatus according to claim 1, characterized in that, The final stage evaporator also includes a steam outlet connected to a vacuum system for condensing the generated water vapor.

6. A method for continuous evaporation of sodium formate, characterized in that, The sodium formate continuous evaporation method is implemented based on the sodium formate continuous evaporation device according to any one of claims 1 to 5, wherein the sodium formate continuous evaporation device further includes a feed pump, a delivery pump, a steam valve, a discharge valve, a temperature sensor, and a liquid level sensor; The feed pump is controlled to send the mixture of formaldehyde removal liquid and mother liquor into the evaporation assembly, where the mixture of formaldehyde removal liquid and mother liquor is continuously evaporated in the first-stage evaporator of the evaporation assembly; The temperature of the steam received in the first-stage evaporator is obtained by a temperature sensor. When the temperature rises to the evaporation temperature threshold, the opening of the steam valve is controlled to evaporate and concentrate the mixture of formaldehyde removal liquid and mother liquor. The temperature of the steam received in the first-stage evaporator is obtained by a temperature sensor. When the temperature rises to the evaporation temperature threshold, the opening of the steam valve is controlled to evaporate and concentrate the material entering the next-stage evaporator. The temperature of the material in the final stage evaporator is obtained by a temperature sensor. When the temperature reaches the temperature threshold, the discharge valve in the final stage evaporator is opened to discharge the material to the crystallization separation system. The solid obtained by separation is sodium formate.

7. The continuous evaporation method for sodium formate according to claim 6, characterized in that, The sodium formate continuous evaporation device also includes a feed valve and a liquid level sensor; The temperature of the material inside the final stage evaporator is obtained by a temperature sensor, and when the temperature reaches a temperature threshold, the discharge valve in the final stage evaporator is opened, including: The liquid level in the final stage evaporator is obtained by a liquid level sensor. When the liquid level reaches the feed threshold, the opening of the feed valve is controlled to keep the material continuously and stably transported to the sodium formate crystallization separation system.

8. The continuous evaporation method for sodium formate according to claim 6, characterized in that, The sodium formate continuous evaporation device also includes a feed valve, a temperature sensor, and a delivery pump; The temperature of the material inside the final stage evaporator is obtained by a temperature sensor, and when the temperature reaches a temperature threshold, the discharge valve in the final stage evaporator is opened, including: The heating temperature of the multi-stage evaporator is obtained by a temperature sensor. When the temperature reaches the evaporation threshold, the delivery pump is controlled to run, and the material is continuously evaporated and concentrated through the multi-stage evaporator.

9. The continuous evaporation method for sodium formate according to claim 6, characterized in that, The sodium formate continuous evaporation device also includes a liquid level sensor and a delivery pump; The temperature of the material inside the final stage evaporator is obtained by a temperature sensor, and when the temperature reaches a temperature threshold, the discharge valve in the final stage evaporator is opened, including: The liquid level of the material in the crystallization separation system is obtained by a liquid level sensor. When the liquid level reaches the separation threshold, the transfer pump is controlled to start, and the sodium formate product is continuously output.

10. The continuous evaporation method for sodium formate according to claim 6, characterized in that, The sodium formate continuous evaporation apparatus also includes a vacuum device and a pressure sensor; The temperature of the material inside the final stage evaporator is obtained by a temperature sensor. When the temperature reaches a temperature threshold, controlling the opening of the discharge valve in the final stage evaporator includes: The evaporation pressure of the final stage evaporator is obtained by a pressure sensor. When the pressure reaches a threshold, the vacuum device is activated to condense the water vapor generated by the final stage evaporator.

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