Design development and experimental investigation of adsorption cooling cum desalination

• Main Author: Chong, Zhi Qiang
• Other Authors: Anutosh Chakraborty
• Format: Final Year Project
• Language: English
• Published: 2015
• Subjects: DRNTU::Engineering::Mechanical engineering::Energy conservation
• Online Access: http://hdl.handle.net/10356/64598
• Institution: Nanyang Technological University

With the increasing need for access to fresh water, desalination can be considered as one of the solution to this problem. However, conventional desalination methods, such as reverse osmosis, are energy intensive and they bring about negative environmental impacts. Adsorption desalination (AD) is an emerging low cost thermal desalination method which utilises waste heat to produce two useful effects, the cooling of space and fresh water production. This report presents on the work done by the author in the design development and experimental investigation of AD systems in NTU. The report begins with an introduction to the theory of Adsorption and basic AD cycle, which is then followed by a literature survey on the past studies done on various type of adsorbents, AD systems and formulations to predict the water uptake of AD cycle. The author also reviewed the report of a previous Final Year Project on the design of a two evaporator system by Lee [1] in order to propose modifications to his design. Firstly, the author added an additional inlet to the adsorption bed cylinder to cater for the two evaporators in the system. The heat exchanger used in the adsorption bed is redesigned to provide a more stable structure. As part of the development work, the author also reported on the installation phases of this AD system. Then, experimental investigations on the performance of zeolite-based commercial adsorption chiller, in terms of specific water production, were performed. By varying the driving temperature, the author was able to estimate the specific water production of the system using a proposed formulation by Sun and Chakraborty [2]. Through the analysis of the results, it is found that the specific water production curves display a cyclic trend and the specific water production peaks at approximately 0.07 kg water/ kg zeolite at a driving temperature of 75°C. Finally, recommendations were made to modify the commercial chiller to ease data collection and also solve the water leakage issue of the chiller. Recommended operating parameters for water production were also given to improve the reliability and accuracy of the results.