Feiler Liubov, Wang Bo
OPTIMIZING EVAPORATION PLANT PERFORMANCE: INNOVATIVE DESIGN FEATURES AND SUSTAINABLE TECHNOLOGICAL SOLUTIONS *
Аннотация:
in the modern chemical industry, it is impossible to imagine producing chemical products without using evaporators. They are presented in various versions, and the choice depends on the characteristics of a particular production. Despite their simplicity and convenience, evaporators have drawbacks. However, it is the task of engineers to find new solutions and minimize these disadvantages. This article presents some methods of calculation and design of modern devices designed for specific chemical solutions. The key design considerations for an evaporative plant include choosing an appropriate type of evaporator, heat source, materials, container geometry, and control systems. Calculation solutions for the selected options are also presented, which will help determine the design features and select materials that contribute to the modernization of the entire device
Ключевые слова:
strength characteristics, control systems, chemical industry
DOI 10.24412/2712-8849-2024-473-695-710
УДК 54.084
Feiler Liubov
master's degree student
Shandong University of Science and Technology
(Qingdao, China)
Wang Bo
professor, Doctor of Chemical Sciences
Shandong University of Science and Technology
(Qingdao, China)
OPTIMIZING EVAPORATION PLANT
PERFORMANCE: INNOVATIVE DESIGN FEATURES
AND SUSTAINABLE TECHNOLOGICAL SOLUTIONS
Abstract: in the modern chemical industry, it is impossible to imagine producing chemical products without using evaporators. They are presented in various versions, and the choice depends on the characteristics of a particular production. Despite their simplicity and convenience, evaporators have drawbacks. However, it is the task of engineers to find new solutions and minimize these disadvantages.
This article presents some methods of calculation and design of modern devices designed for specific chemical solutions. The key design considerations for an evaporative plant include choosing an appropriate type of evaporator, heat source, materials, container geometry, and control systems. Calculation solutions for the selected options are also presented, which will help determine the design features and select materials that contribute to the modernization of the entire device.
The development and design of evaporation plants require careful attention to details regarding various design features to ensure their efficiency, reliability and operability. This summary provides a brief overview of the key design aspects necessary for the successful implementation and operation of such installations. The optimal choice of material, its strength characteristics and the minimum allowable thickness of the material for creating the device are also considered. These features are the key points that engineers should consider when building the device because every detail makes up a percentage of long-term operation, safety, productivity and efficiency.
Keywords: strength characteristics, control systems, chemical industry.
Introduction.
Evaporation is a thermal process of concentrating solid solutions by boiling and partially removing the liquid solvent in the form of vapor. The chemical and related industries distinguish liquid mixtures, which are concentrated through evaporation, based on a wide variety of physical parameters such as viscosity, density, boiling point, critical heat flow and etc, as well as other characteristics such as crystallizing, foaming and non-heat-resistant solutions. The properties of the mixtures determine the basic requirements for the process conditions (vacuum evaporation, direct and counter flow, single and multi-stage multi-effect evaporation plants), as well as for the designs of evaporators. In technology, the process of evaporation has become widespread since many substances (sugar, table salt, alkali metals, ammonium nitrate and many others) are obtained in the form of weak liquid solutions and a form ready for consumption, storage or transport they must be entirely or partially dehydrated.
Thus the evaporation plant is an essential equipment element in many chemical, food and other industries. The regular operation of a workshop or factory as a whole often depends on its correct calculation and design. In general the choice of an evaporator installation scheme is an optimal search task and is carried out by a technical and economic comparison of various options using a computer. For the first time, evaporation was used as a technological process to produce sugar. In the modern chemical industry, where the optimization of thermal processes plays a crucial role, evaporators play a key role in producing concentrates of various products. The technologies in this area require refinement and continuous development to increase process efficiency and ensure high quality final products.
In this manuscript we will focus on considering a natural circulation evaporator. Such devices are characterized by simplicity of design and reliability in operation. They carry out the evaporation process without additional energy consumption, making them particularly attractive regarding energy savings.
However, despite their advantages natural circulation evaporators also have certain limitations and drawbacks, including constraints in process control and the need for modernization to enhance efficiency.
In this manuscript we will examine the features of such an apparatus's operation, its advantages and disadvantages and present new ideas for its modernization and improvement. This will partially address some of the identified problems and increase its efficiency.
The scheme and principle of operation of the device.
The evaporator consists of a heating chamber, a separator with a splash separator and a circulation pipe1. The heating chamber is a bundle of pipes enclosed in a cylindrical shell. The upper and lower ends of the pipes are rolled into tube sheets welded to the ends of the shell. A transition chamber with a fitting for connection to the separator is attached to the upper tube sheet. The separator is a cylindrical vessel with an elliptical top cover and a flat bottom.
Fig.1. Design diagram of device.
1 – Elliptical separator cover,
2 – Separator shell, 3 – Con-ical separator bottom,
4 – Conical heating chamber cover, 5 – Heating chamber shell,
6 – Elliptical heating chamber bottom, 7 – circulation pipe.
A splash separator is located in the upper part of the separator. The separator's design allows for the installation of a cyclone or louvered spray separator, depending on the specific evaporation conditions. The flat bottom is connected to a circulation pipe which is connected to the lower chamber using an elbow. The solution in the apparatus circulates along a closed circuit: separator—circulation pipe—heating chamber—separator. The evaporated solution rising through the pipes heats up and boils as it rises. The resulting vapor solution mixture is directed tangentially to the separator, where it is separated into liquid and vapor phases. The secondary steam passing through the separator and splash separator is freed from drops and leaves the apparatus through fitting B and the solution returns through the circulation pipe to the heating chamber. Heating steam enters the annulus through fitting A, where it condenses. Condensate is removed through fitting B. The solution is fed into the apparatus through fitting G, depending on the operating mode of the apparatus. Secondary steam escapes through port B. The choice of structural materials for the designed apparatus is determined by the technological process's characteristics occurring in it, the properties of the working substances, their parameters and the nature of the mechanical load. In turn the technological properties of the structural material predetermine the method of manufacturing apparatus parts from it.
Heat exchangers are usually manufactured in specialized factories. A significant part of the products of these factories is standardized and presented in catalogs and price tags. In addition to specialized factories, heat exchangers are manufactured according to individual orders and drawings by non-specialized machine building plants and workshops. Regardless of the place of design and manufacture, heat exchangers intended to operate under pressure above 0.7 atm excess must comply with the rules of Promatomnadzor regarding design, installation and operation4. According to the "Rules for the Design and Safety of Operation of Pressure Vessels," the organization that developed the design and performed its calculations is responsible for the correct design of the vessel, its precision of calculations and the choice of material. All changes that may arise during the vessel's manufacturing or installation must be agreed upon between the organization drawing up the project and the organization that requires the design change, documented in a protocol and signed by both parties4. The primary material for manufacturing heat exchange equipment is rolled steel of various grades.
Steel heat exchangers are widely used in energy, chemical, oil refining, food, light and other industries. Many devices for mass use (cogeneration heaters, condensers, evaporators, distillation columns of some types and etc.) are standardized and manufactured by specialized factories and workshops in large quantities. The device is manufactured based on a technological process, the degree of perfection of which determines the quality, labor intensity and production time of the product, as well as the need for mechanical assembly, special equipment and qualified labor5. The technological process is usually selected after comparing several options. The technological process provides for the order of manufacture of individual parts and assemblies and the sequence of assembly of the product.
The first part of the technological process development contains detailed information about the quality and procedure for manufacturing the device according to the technical specifications:
And final control and test conditions for the finished product.
The second part of the development of the technological process is devoted to the selection of rational operations for processing parts, the sequence of work operations as well as the selection of the most rational equipment, tools and devices. The third part of the development determines the qualifications of workers for various operations of the technological process, the labor intensity of work for each operation and throughout the entire manufacturing process of the product, the duration of each operation, the amount of auxiliary materials consumed, the size of the required production area and installation location. We select a stable construction material in a boiling K2CO3 solution at a concentration range of 6.9 to 55%. Under these conditions, steel grade X17 is chemically resistant, Its corrosion rate is not less than 0.1 mm/year and its thermal conductivity coefficient lst = 25.1 W/(m K).
Calculation of wall’s thickness.
The reasons that make this step so important are to ensure its resilience and stability under specified operating conditions and the ability to determine the optimal thickness of the apparatus' wall 1. The main formula for calculating the thickness of the apparatus wall is:
Fig.2. Shell.
Where:
This calculation enables engineers to make informed decisions during the equipment's design and operating phases. Moreover, it assists in optimizing the apparatus's structure and reducing the risk of unexpected emergencies.
This calculation can reduce heat transfer and minimize budget by optimizing materials during the construction. By correctly determining the wall thickness and ensuring the necessary strength, reducing cooling and energy costs, An effective thermal insulation can be achieved. Accordingly, this enables resource protection and leads to the energy efficiency of technological processes [1, 2].
Thus, this calculation has provided new insights, allowing for the wall thickness adjustment tailored to the specific conditions and apparatus, minimizing construction costs while slightly increasing the outcome.
Calculation of the thickness of the flat bottom of the separator.
After calculating the maximum thickness of the apparatus wall, another question arises about the strength of the apparatus itself. At this stage, it is necessary to calculate the thickness of the flat bottom of the separator. Why is this necessary, and why?
Calculating the thickness of the separator's flat bottom is necessary to ensure its strength and stability during operation under certain load conditions. The separator's flat bottom is one of the key elements of the design, which has to withstand pressure from the internal environment and mechanical impacts. Conducting the calculation allows for determining the optimal thickness of the bottom, which ensures its reliable operation and protects it from possible damage or deformation.
Fig. 3. Scheme of fastening the flat bottom to the shell.
Additionally, calculating the thickness of the separator's flat bottom allows meeting the requirements for the equipment's safety and reliability and reducing the risk of emergencies during operation. The calculation takes into account various factors, such as pressure, temperature, construction material, and the technological process's peculiarities.
In conclusion, calculating the thickness of the separator's flat bottom is an essential step in the design and modernization of equipment, as it ensures its reliable and safe operation in the chemical industry.
For this calculation, let's use the formula:
Where:
When calculating the thickness of the flat bottom of the separator, it is necessary to consider not only the design pressure in the apparatus but also the fulfillment of strength conditions both during operation and during testing. The operating pressure (P) and the test pressure (PI) play a key role in ensuring the reliability and safety of the separator's operation.
Our obtained data, [P] > P_P (1.91 MPa > 0.64 MPa) and [P]I > PI (2.02 MPa > 0.94 MPa), indicate that the calculation method yielded successful results. The strength conditions are met, which corresponds to all safety and reliability requirements for the operation of the apparatus.
The results are successful and open up new and beneficial knowledge in the design and operation of separators. This method of calculating the thickness of the separator's flat bottom demonstrates its effectiveness and importance in ensuring the safety and reliability of technological processes. The results show that adequately selected parameters and consideration of all factors provide optimal conditions for the operation of the apparatus and reduce the risk of emergencies.
Calculation of the thickness of the elliptical separator cover.
When discussing the importance of the evaporator apparatus's durability and safety, one cannot overlook the calculation of the thickness of the elliptical separator's cover, as it plays a crucial role in ensuring its strength and stability during operation. The cover is one of the main elements of the separator's structure and is subjected to significant mechanical loads, including internal pressure and the effects of the surrounding environment [1,4].
Calculating the thickness of the cover allows for determining the optimal material and geometry parameters necessary to ensure its reliable operation under specified operating conditions. This calculation also contributes to compliance with safety requirements and quality standards and helps prevent possible damage or deformation of the cover during operation5. When calculating the thickness of the elliptical separator's cover, various factors must be considered, including internal pressure, mechanical loads, chemical environment, operating temperature, and other parameters. This ensures not only the strength and stability of the cover but also prevents corrosion and other forms of damage that may lead to equipment malfunctions.
Furthermore, it is essential to consider the interaction of the cover with other elements of the separator, such as the housing and bottom. The optimal combination of cover thickness with other construction parameters enables the equipment to achieve the best performance and durability.
Fig. 4. Cover.
It is worth noting that the development of new materials and technologies can also influence the calculation of the thickness of the separator's cover. Applying new materials with improved mechanical properties or using innovative material processing methods can enhance the structure's efficiency and reliability1.
In conclusion, calculating the thickness of the elliptical separator's cover is a significant engineering task that requires considering multiple factors to ensure optimal equipment performance, safety, and durability.
In our scientific article, we propose a new approach to calculating the parameters of the evaporative apparatus, which is based on modern engineering methods and takes into account numerous factors affecting its performance and safety. This alternative calculation method has been developed with the aim of improving the efficiency and reliability of the apparatus in the chemical industry.
For this calculation, let's use the formula:
Also, one should not forget to calculate the working pressure and test pressure. Our pressure also meets all the requirements since [P] > P(2.1 MPa > 0.64 MPa) and [P]I > PI (2.12 MPa > 0.94 MPa) - the strength condition is met. This once again speaks to the usefulness and correctness of this calculation method.
Calculation of interface node locations.
Calculation of the positioning of interface nodes is crucial for ensuring the optimal performance and safety of the evaporator apparatus. These interface nodes serve as connection points between various components and systems within the apparatus, facilitating the transfer of materials, energy, and information.
Determining the precise location of these interface nodes is essential for several reasons. Firstly, it ensures proper alignment and coordination between different subsystems, such as heating, condensation, and liquid transfer systems. Incorrect positioning of interface nodes can lead to inefficiencies, malfunctions, or even safety hazards in the operation of the apparatus [2, 6].
Secondly, accurate calculation of interface node positioning helps to streamline maintenance and repair procedures. Access to critical components for inspection, maintenance, and replacement is essential for ensuring the longevity and reliability of the evaporator apparatus. Improperly positioned interface nodes may impede access to these components, leading to difficulties in servicing and increased downtime.
Furthermore, failure to conduct calculations for interface node positioning can result in structural integrity issues. Improperly distributed loads or stresses on the apparatus due to misaligned interface nodes may lead to structural failures, leaks, or other mechanical problems, compromising the safety and operability of the system [2, 4].
In summary, conducting calculations for the positioning of interface nodes is necessary to ensure the efficient operation, maintenance, and safety of the evaporator apparatus. It helps to prevent operational inefficiencies, maintenance difficulties, and structural integrity issues that could arise from improper positioning. Therefore, careful consideration and accurate calculation of interface node locations are vital steps in the design and optimization of evaporator systems.
Fig. 5. Calculation diagram of the connection of a cylindrical
shell with a flat bottom of the separator.
This article provides a calculation diagram for connecting the cylindrical shell with the flat bottom of the separator. The formulas used for calculating the connection may include the following:
Formula for determining the stress in the shell, taking into account the internal pressure and geometric parameters of the shell.
Formula for determining the stress in the separator's bottom, considering the internal pressure and geometric parameters of the bottom1.
Formula for determining the bonding force between the cylindrical shell and the flat bottom, considering contact parameters and the geometry of the connection1.
Formula for calculating the required thickness of the weld or bolted joint to ensure sufficient strength of the connection1.
Due to the complexity of the calculations, they are not presented in this article. However, it is crucial not to overlook them, as they play a significant role in ensuring the integrity and reliability of the separator's structure.
The logical next step would be to commence with the calculation of the reinforcement of the opening fitting of the heating chamber. However, it is essential to consider that our analysis is not limited to this single calculation. We will also explore other critical aspects associated with the heating chamber, including the assessment of thermal losses and determining the optimal material and geometry to enhance the heating process efficiency. These and other calculations and methodologies will be extensively discussed in the following article, where we will present a more comprehensive and in-depth exploration of this topic.
Conclusion.
Summing up, we can draw several significant conclusions. Firstly, this article presents an overview of the main aspects of the design and calculation of parameters of evaporation plants. Which overrides our considerations necessary for the efficient and safe operation of these installations. In the beginning, we considered the importance of choosing the right type of spoiler based on the originally set tasks. This choice can minimize the disadvantages as much as possible and improve the performance of the evaporator itself in the future.
Secondly, the right materials will play a key role in the viability of the structure. Any errors in the choice of material can lead to malfunction of the device. Therefore, this choice should be approached with maximum awareness, the material must meet all requirements and be resistant to aggressive environments.
Thirdly, the geometry of each part of the device! The geometric configuration of the tank affects the efficiency of heat transfer and the overall performance of the installation. The use of modern control systems makes it possible to optimize energy consumption and ensure stable product quality.
We paid special attention to the calculation of the main components of the system. Calculation of the wall thickness, calculation of the thickness of the flat bottom of the separator, calculation of the thickness of the elliptical lid, calculation of the connection of the cylindrical shell with the flat bottom of the separator and so on. Based on these calculations, a design is created. Thanks to them, we can give a full account of the operability and safety of the device. The calculations and methods presented in the article are aimed at improving the efficiency and reliability of evaporation plants in the chemical industry. They provide engineers with the tools to create optimal and safe structures that meet production and energy efficiency requirements.
If we delve further into the research of this area, it is possible to come to even more effective and innovative solutions. Since accurate calculations and design features of each evaporation plant are crucial and require the most competent approach of an engineer. When designing an evaporator, many factors must be taken into account to ensure its reliable and safe operation.
In this article, we have considered only a part of the modern calculation methods that allowed us to develop a design for a vaporizer with minimal losses and a modern design. Of course, there are many different solutions in the modern world, but there is no limit to perfection. Continuous research and development of new technologies and calculation methods will allow us to achieve even higher efficiency and reliability in the design and operation of evaporators. In future publications, we plan to take a closer look at other components of the evaporator, such as the heater, in order to comprehensively cover all aspects of its operation and design.
REFERENCES:
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Ссылка для цитирования:
Feiler Liubov, Wang Bo OPTIMIZING EVAPORATION PLANT PERFORMANCE: INNOVATIVE DESIGN FEATURES AND SUSTAINABLE TECHNOLOGICAL SOLUTIONS // Вестник науки №4 (73) том 2. С. 695 - 710. 2024 г. ISSN 2712-8849 // Электронный ресурс: https://www.вестник-науки.рф/article/13889 (дата обращения: 17.05.2024 г.)
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