Waste heat recycling device for mechanical straw pulping
By setting up steam recovery pipelines and induced fans during the straw mechanical pulping process, high-temperature steam is recycled and utilized, the problem of unused waste heat is solved, energy and water resources are saved, carbon dioxide emissions are reduced, and carbon dioxide emissions are passed through external pipelines and interlayers The cavity structure reduces heat loss and improves recycling efficiency.
Patent Information
- Application Number
- CN202420773471.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-04-15
- Publication Date
- 2025-01-10
- Estimated Expiration
- 2034-04-15
AI Technical Summary
The waste heat generated during the existing straw mechanical pulping process has not been effectively utilized, resulting in waste of energy and water resources and an increase in carbon dioxide emissions.
Design a waste heat recovery device for mechanical pulping of straw. By setting up a steam recovery pipeline between the high-concentration grinding reaction chamber and the steam steam silo, and installing a induced fan, high-temperature steam is introduced into the steam silo for recycling. Combining the outer pipe and sandwich cavity structure reduces heat loss.
Effectively save energy and water resources, reduce carbon dioxide emissions, and achieve the recovery of 8 tons of high-temperature steam from 40 tons of high-temperature agricultural straw fiber every day, save electric steam and water resources, reduce costs, and reduce heat loss by optimizing the steam recovery pipeline structure.
Smart Images
Figure CN222332369U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of steam recovery and utilization in straw mechanical pulping, in particular to a waste heat recovery and utilization device used in straw mechanical pulping. Background Art
[0002] like Figure 1 As shown, the existing straw mechanical pulping steps are as follows:
[0003] 1) Agricultural straw is cut and screened to remove the waste materials such as leaves, ears and skin, and obtain straw chips;
[0004] 2) Wash the above-mentioned straw slices to remove impurities and dehydrate them to obtain washed materials. The water is precipitated to remove dust, sand and other impurities, and is repeatedly used for washing straw slices;
[0005] 3) The washed material is transferred to a steaming bin, and high-temperature steam of 100-140°C is introduced, and the temperature is kept at 90-120°C for 10-60 minutes to perform steaming and softening; after steaming, a twin-screw extruder is used for solid-liquid separation to obtain steaming liquid and steaming material;
[0006] 4) Adding sodium hydroxide equivalent to 1%-10% of the absolute dry weight to the steamed material, and adding an appropriate amount of water to make the solid concentration of the system 10-30%, and mixing them evenly, and inputting them into the pre-impregnation bin; passing 100-140°C high-temperature steam into the pre-impregnation bin, maintaining the temperature at 90-120°C for pre-impregnation for 10-60 minutes; obtaining the pre-impregnation material;
[0007] 5) The pre-impregnated material is input into a disc refiner for pulping. During the pulping process, the distance between the grinding disc and the grinding disc is 0.1 mm. The disc refiner is processed 4 times to obtain agricultural straw fibers with different freeness. Then, high-concentration pulping, pulping, washing and screening are carried out to obtain pulp fibers.
[0008] In the above step 5, the pre-impregnated material is input into the disc refiner for pulping. Since a large amount of heat energy is generated during the pulping process, the material temperature of the agricultural straw fibers with different freeness obtained after pulping is as high as 110°C, and a large amount of steam is generated. In the prior art, these waste heats are not utilized but wasted.
[0009] Therefore, in order to solve the above problems, it is necessary to develop a waste heat recovery and utilization device for straw mechanical pulping. Utility Model Content
[0010] The purpose of the utility model is to provide a waste heat recovery and utilization device for straw mechanical pulping in view of the shortcomings of the prior art; the technical scheme is as follows:
[0011] A waste heat recovery and utilization device for mechanical pulping of straw comprises a high-concentration grinding reaction chamber and a steaming chamber; a steam recovery pipeline is arranged between the high-concentration grinding reaction chamber and the steaming chamber, and an induced draft fan is correspondingly installed on the steam recovery pipeline. The high-temperature steam generated by the high-concentration grinding reaction chamber can be introduced into the steaming chamber for recovery and utilization through the induced draft fan and the steam recovery pipeline.
[0012] Furthermore, the steam recovery pipeline includes a front-end pipeline and a rear-end pipeline installed as one; the front-end pipeline is connected to the high-concentration grinding reaction chamber, the rear-end pipeline is connected to the steaming chamber, and the inner diameter of the rear-end pipeline is smaller than that of the front-end pipeline.
[0013] Furthermore, a temperature measuring meter is installed at the rear end of the steam recovery pipeline, and the temperature measuring meter can measure the temperature value of the recovered hot steam when it enters the steaming bin.
[0014] Furthermore, an outer pipe is provided outside the steam recovery pipe, and the outer pipe sleeves the steam recovery pipe inside, the outer pipe and the steam recovery pipe are arranged cocentrically, and an interlayer cavity is provided between the outer pipe and the steam recovery pipe;
[0015] The high-concentration grinding reaction chamber is also provided with a bypass pipe, which is connected to the interlayer cavity of the outer pipe, and a bypass fan is also arranged on the bypass pipe; the steaming chamber is also provided with a bypass pipe, which is also connected to the interlayer cavity of the outer pipe.
[0016] Furthermore, the outer pipe is a detachable structure outside the steam recovery pipe.
[0017] Furthermore, a vertical mounting circular plate is installed on the front and rear sides of the steam recovery pipe, and mounting ring plates corresponding to the positions of the mounting circular plates are provided on both side ends of the outer pipe. After the positions of the mounting circular plates and the mounting ring plates on both sides correspond to each other, they are fixed accordingly by fixing parts, so that the outer pipe is installed correspondingly on the outside of the steam recovery pipe.
[0018] Furthermore, the mounting ring plate and the mounting circular plate are also provided with sealing gaskets.
[0019] Beneficial effects: The utility model has the following beneficial effects:
[0020] 1) In the high-concentration grinding step, the device sets a steam recovery pipeline and installs an induced draft fan between the reaction chamber and the steaming chamber, which can introduce the hot steam generated by the high-concentration grinding into the steaming chamber for recycling, effectively saving energy and water resources, saving costs for the enterprise, and reducing carbon dioxide emissions;
[0021] 2) In this device, a straw mechanical pulping production line with an annual production capacity of 15,000 tons of straw pulp fiber can produce 40 tons of agricultural straw fiber per day with a moisture content of about 60%. This device recovers 8 tons of high-temperature steam at a temperature of 110°C from the 40 tons of high-temperature agricultural straw fiber produced every day, that is, the front-end steam storage bin can save 8 tons of steam. The steam in the original steam storage bin is provided by an electric steam generator, which generates an economic value of more than 2,400 yuan per day, saves 0.8 tons of standard coal, and saves 8 tons of water, effectively saving costs;
[0022] 3) In this device, the steam recovery pipeline is set to have a larger inner diameter at the front end and a smaller inner diameter at the rear end, which can effectively increase the flow rate of hot steam in the steam recovery pipeline and reduce the heat loss of hot steam in the steam recovery pipeline;
[0023] 4) The device is also provided with an external pipeline, and a sandwich cavity is formed between the external pipeline and the steam recovery pipeline, and part of the steam is introduced into the cavity through the bypass pipeline and the bypass fan, which can effectively slow down the heat loss of the hot steam in the recovery pipeline of the scale;
[0024] 5) The inner and outer pipes of the device are detachable through the installation circular plate and the installation ring, which is convenient for installation and disassembly and has a more reasonable structure. BRIEF DESCRIPTION OF THE DRAWINGS
[0025] Figure 1 It is a flow chart of mechanical pulping of straw in the prior art;
[0026] Figure 2 This is the flow chart of the straw mechanical pulping of the utility model;
[0027] Figure 3 This is a structural diagram of Embodiment 1 of the utility model;
[0028] Figure 4 This is a structural diagram of the steam recovery pipeline in Example 1 of the utility model;
[0029] Figure 5 This is a structural diagram of Embodiment 2 of the present utility model;
[0030] Figure 6 This is a diagram of the internal and external pipeline structure of Example 2 of the utility model;
[0031] Figure 7 for Figure 6 Middle AA section view. DETAILED DESCRIPTION
[0032] The present invention is further explained below in conjunction with the accompanying drawings and specific embodiments. The embodiments are implemented based on the technical solution of the present invention. It should be understood that these embodiments are only used to illustrate the present invention and are not used to limit the scope of the present invention. Example 1
[0033] like Figure 2 , Figure 3 and Figure 4 As shown, a waste heat recovery and utilization device for straw mechanical pulping in this embodiment includes a high-concentration grinding reaction chamber 1 and a steam steaming chamber 2; a steam recovery pipeline 3 is arranged between the high-concentration grinding reaction chamber 1 and the steam steaming chamber 2 in this embodiment, and an induced draft fan 4 is correspondingly installed on the steam recovery pipeline 3. The high-temperature steam generated by the high-concentration grinding reaction chamber 1 can be introduced into the steam steaming chamber 2 for recovery and utilization through the induced draft fan 4 and the steam recovery pipeline 3.
[0034] The steam recovery pipeline 3 of this embodiment includes a front-end pipeline 31 and a rear-end pipeline 32 installed as one body; the front-end pipeline 31 of this embodiment is connected to the high-concentration grinding reaction chamber 1, and the rear-end pipeline 32 of this embodiment is connected to the steam steaming chamber 2, and the inner diameter of the rear-end pipeline 32 of this embodiment is smaller than that of the front-end pipeline 31.
[0035] In this embodiment, a temperature measuring meter 5 is further installed at the rear end of the steam recovery pipe 3 , and the temperature measuring meter 5 can measure the temperature value of the recovered hot steam when it enters the steaming bin 2 .
[0036] like Figure 2 As shown, the technical solution of this embodiment is to install a steam recovery pipeline between the high-concentration grinding reaction chamber and the steam steaming chamber in the high-concentration grinding step, and a draft fan is installed on the steam recovery pipeline. The high-temperature steam generated by the high-concentration grinding is introduced into the steam steaming chamber through the steam recovery pipeline by the draft fan, so as to reduce the original external steam input, save energy, and save water resources. Finally, the agricultural straw fiber after waste heat utilization is washed, screened and concentrated to obtain pulp fiber.
[0037] In the prior art, a straw mechanical pulping production line that produces 15,000 tons of straw pulp fiber annually can produce 40 tons of agricultural straw fiber every day, with a moisture content of about 60%. This embodiment recovers 8 tons of high-temperature steam with a temperature of 110°C from the 40 tons of high-temperature agricultural straw fiber produced every day, that is, the front-end steam bin can save 8 tons of steam. The steam in the original steam bin is provided by an electric steam generator, which generates an economic value of more than 2,400 yuan per day, saves 0.8 tons of standard coal, and saves 8 tons of water at the same time.
[0038] In addition, this embodiment sets the steam recovery pipeline to have a larger inner diameter at the front end and a smaller inner diameter at the rear end, which can effectively increase the flow rate of hot steam in the steam recovery pipeline and reduce heat loss of hot steam in the steam recovery pipeline. Example 2
[0039] like Figure 5 , Figure 6 and Figure 7As shown, a waste heat recovery and utilization device for straw mechanical pulping in this embodiment includes a high-concentration grinding reaction chamber 1 and a steam steaming chamber 2; a steam recovery pipeline 3 is arranged between the high-concentration grinding reaction chamber 1 and the steam steaming chamber 2 in this embodiment, and an induced draft fan 4 is correspondingly installed on the steam recovery pipeline 3. The high-temperature steam generated by the high-concentration grinding reaction chamber 1 can be introduced into the steam steaming chamber 2 for recovery and utilization through the induced draft fan 4 and the steam recovery pipeline 3.
[0040] The steam recovery pipeline 3 of this embodiment includes a front-end pipeline 31 and a rear-end pipeline 32 installed as one body; the front-end pipeline 31 of this embodiment is connected to the high-concentration grinding reaction chamber 1, and the rear-end pipeline 32 of this embodiment is connected to the steam steaming chamber 2, and the inner diameter of the rear-end pipeline 32 of this embodiment is smaller than that of the front-end pipeline 31.
[0041] In this embodiment, a temperature measuring meter 5 is further installed at the rear end of the steam recovery pipe 3 , and the temperature measuring meter 5 can measure the temperature value of the recovered hot steam when it enters the steaming bin 2 .
[0042] The steam recovery pipe 3 of this embodiment is further provided with an outer pipe 6, and the steam recovery pipe 3 is correspondingly sleeved inside the outer pipe 6. The outer pipe 6 and the steam recovery pipe 3 are arranged cocentrically, and an interlayer cavity 7 is arranged between the outer pipe 6 and the steam recovery pipe 3.
[0043] The high-concentration grinding reaction chamber 1 of the present embodiment is also provided with a bypass pipe 8, which is connected to the interlayer cavity 7 of the outer pipe 6, and a bypass fan 9 is also arranged on the bypass pipe 8; the steaming chamber 2 of the present embodiment is also provided with a bypass pipe 8, which is also connected to the interlayer cavity 7 of the outer pipe 6.
[0044] The outer pipe 6 of this embodiment is a detachable structure outside the steam recovery pipe 3 .
[0045] A vertical mounting circular plate 10 is installed on the front and rear sides of the steam recovery pipe 3 of the present embodiment, and mounting ring plates 11 corresponding to the positions of the mounting circular plates 10 are provided on both side ends of the outer pipe 6 of the present embodiment. After the mounting circular plates 10 and the mounting ring plates 11 on both sides correspond in position, they are fixed accordingly by the fixing members 12, so that the outer pipe 6 is correspondingly installed on the outside of the steam recovery pipe 3; the mounting ring plates 11 and the mounting circular plates 10 of the present embodiment are also provided with sealing gaskets.
[0046] The technical solution of this embodiment is to make further improvements to the steam recovery pipeline on the basis of the technical structure of Embodiment 1; since in actual use, there may be a certain distance between the high-concentration grinding equipment and the steam steaming bin equipment, the length of the steam recovery pipeline may also be relatively long, and the hot steam may lose more heat energy in the steam recovery pipeline.
[0047] The technical solution of this embodiment is to set a concentric outer pipe outside the steam recovery pipe, and bypass pipes are installed on both sides of the left and right sides of the outer pipe, which are respectively connected to the high-concentration grinding reaction chamber and the steam steaming chamber on the left through the bypass pipes, and bypass fans are correspondingly arranged. Then, a small part of the hot steam in the high-concentration grinding reaction chamber can be passed into the interlayer cavity of the outer pipe through the bypass fan. The interlayer cavity serves as the external thermal insulation interlayer of the steam recovery pipe, and the heat loss of the hot steam flowing inside will be reduced accordingly.
[0048] In addition, this embodiment specifically arranges the structural installation of the outer pipe, and the outer pipe is arranged to be detachable and installed, specifically by docking and installing the mounting circular plates on both sides of the steam recovery pipe and the mounting ring plates on both sides of the outer pipe, so the structural arrangement is more reasonable and effective.
[0049] The above-mentioned specific implementation mode is only a preferred embodiment of the present invention and is not intended to limit the implementation of the present invention and the scope of the claims. All equivalent changes and modifications made according to the content of the patent protection scope of the present invention should be included in the scope of the patent application of the present invention.
Claims
1. A waste heat recovery device for straw mechanical pulping, characterized in that: The invention comprises a high-concentration grinding reaction chamber (1) and a steaming chamber (2); a steam recovery pipe (3) is arranged between the high-concentration grinding reaction chamber (1) and the steaming chamber (2); an induced draft fan (4) is correspondingly installed on the steam recovery pipe (3); and high-temperature steam generated by the high-concentration grinding reaction chamber (1) can be introduced into the steaming chamber (2) for recycling through the induced draft fan (4) and the steam recovery pipe (3).
2. The waste heat recovery and utilization device for straw mechanical pulping according to claim 1 is characterized in that: The steam recovery pipeline (3) comprises a front-end pipeline (31) and a rear-end pipeline (32) which are installed in an integrated manner; the front-end pipeline (31) is connected to the high-concentration grinding reaction chamber (1), and the rear-end pipeline (32) is connected to the steaming chamber (2), and the inner diameter of the rear-end pipeline (32) is smaller than that of the front-end pipeline (31).
3. The waste heat recovery and utilization device for straw mechanical pulping according to claim 1 is characterized in that: A temperature measuring meter (5) is also installed at the rear end of the steam recovery pipe (3), and the temperature measuring meter (5) can measure the temperature value of the recovered hot steam when it enters the steaming bin (2).
4. The waste heat recovery and utilization device for straw mechanical pulping according to claim 1 is characterized in that: An outer pipe (6) is further provided on the outside of the steam recovery pipe (3), and the outer pipe (6) sleeves the steam recovery pipe (3) therein; the outer pipe (6) and the steam recovery pipe (3) are arranged cocentrically, and an interlayer cavity (7) is provided between the outer pipe (6) and the steam recovery pipe (3); The high-concentration grinding reaction chamber (1) is also provided with a bypass pipe (8), which is connected to the interlayer chamber (7) of the outer pipe (6), and a bypass fan (9) is also arranged on the bypass pipe (8); the steaming chamber (2) is also provided with a bypass pipe (8), which is also connected to the interlayer chamber (7) of the outer pipe (6).
5. The waste heat recovery and utilization device for straw mechanical pulping according to claim 4 is characterized in that: The outer pipe (6) is a detachable structure outside the steam recovery pipe (3).
6. The waste heat recovery and utilization device for straw mechanical pulping according to claim 5 is characterized in that: A vertical mounting circular plate (10) is installed on the front and rear sides of the steam recovery pipe (3), and mounting ring plates (11) corresponding to the positions of the mounting circular plates (10) are provided on both side ends of the outer pipe (6). After the mounting circular plates (10) and the mounting ring plates (11) on both sides are positioned correspondingly, they are fixed accordingly by means of fixing members (12), so that the outer pipe (6) is mounted correspondingly on the outside of the steam recovery pipe (3).
7. The waste heat recovery and utilization device for straw mechanical pulping according to claim 6 is characterized in that: The mounting ring plate (11) and the mounting circular plate (10) are also provided with sealing gaskets.