Liquid desiccant dehumidification system design and experimental performance testing

• Main Author: Gu, Haoran
• Other Authors: Cai Wenjian
• Format: Theses and Dissertations
• Language: English
• Published: 2019
• Subjects: DRNTU::Engineering::Electrical and electronic engineering::Control and instrumentation::Control engineering
• Online Access: http://hdl.handle.net/10356/78478
• Institution: Nanyang Technological University

In this fast-growing society, people are increasingly demanding quality of life. Among them, indoor air quality, especially indoor air humidity, has been paid attention. However, in the conventional system, the dehumidification function and the temperature control function cannot fully achieve the expected goals. Moreover, when the system works, the energy consumption is very high, resulting in a large amount of energy waste. Therefore, the development of a multi-functional and low energy consumption air conditioning system has been the development goal of the current control industry. In this thesis, an energy-efficient liquid desiccant dehumidification system (LDDS) was designed and developed. Starting from the limitations of the existing liquid desiccant dehumidification air conditioning system, the heat pipe recovery, and energy storage concept was applied to the LDDS for the first time, and the dehumidification regeneration mixed operation mode was proposed. Compared with existing LDDS, the designed system has significantly improved as energy saving (by using solar energy and industrial waste heat), dehumidification efficiency (by using lithium chloride as the dehumidifier), application range (can be used in industrial or domestic). Based on the laws of conservation of energy and mass, the heat and mass transfer process in the dehumidifier and regenerator is analyzed. A hybrid modeling method is proposed to establish a model of LDDS. The relative error between the predicted and experimental values of the model is less than 15%. The proposed model has the advantages of simple form, low computational complexity, no need for iterative calculation. It can be applied to application fields such as performance prediction of LDDS. In the LDDS performance analysis section, the dehumidifier and regenerator were tested separately. During the test of the dehumidifier, cooling and dehumidification performance in the dehumidifier are analyzed by changing parameters such as air flow rate, solution flow rate, and chilled water flow rate. Similarly, the regeneration performance changes in the regenerator are analyzed by changing the air flow rate and the solution flow rate in the regenerator.