On the experimental study of composite dessicants for energy efficient air dehumidification

• Main Authors: Chua, K.J., Islam, Rafiqul
• Format: Article
• Language: English
• Published: IIUM Press 2015
• Subjects: TJ Mechanical engineering and machinery
• Online Access: http://irep.iium.edu.my/50267/1/50267.pdf; http://irep.iium.edu.my/50267/; http://journals.iium.edu.my/ejournal/index.php/iiumej/article/view/600

This paper presents the development and performance characterization of new composite desiccants. The main compositions for the composite desiccants include silica gel, lithium chloride, calcium chloride and bentonite. Different percentage compositions of these four components were tested to determine the optimal material composition for improving moisture removal capacity under varying inlet air temperature and humidity, and amount of moisture released under different regenerative temperature. For the first time, four-layered composite desiccants were developed and tested experimentally to determine their moisture removal capacity and moisture regeneration capacity at temperature of about 60oC under inlet air conditions similar to Singapore’s tropical climate. The performances of these composite desiccants were benchmarked with the performance of pure silica gel - the most commonly used desiccant in the market today. It was observed experimentally, that employing a four-layered composite desiccant, comprising silica-gel (SiO2), Bentonite, Lithium Chloride (LiCl), and Calcium Chloride (CaCl2), has enabled greater moisture removal capacity for varying inlet air temperature and humidity ranging from 25 to 35oC and 55 to 95% relative humidity (RH). The percentage improvements, in contrast to pure silica gel, are 14 to 22.5%, and 10 to 26.3% for varying inlet air temperature and varying inlet RH, respectively. : Kertas kerja ini membentangkan perkembangan dan prestasi pencirian desiccants komposit baru. Komposisi utama bagi desiccants komposit termasuk gel silika, litium klorida, kalsium klorida dan bentonit. Peratusan komposisi yang berbeza daripada empat komponen telah diuji untuk menentukan komposisi bahan yang optimum untuk meningkatkan penyingkiran kapasiti kelembapan di bawah pelbagai suhu masuk udara dan kelembapan, dan jumlah kelembapan dikeluarkan di bawah suhu regeneratif yang berbeza. Buat kali pertama, desiccants komposit empat lapis telah dibangunkan dan diuji secara eksperimen untuk menentukan penyingkiran kelembapan kapasiti dan kelembapan kapasiti penjanaan semula mereka pada suhu kira-kira 60oC di bawah keadaan udara masuk sama dengan iklim tropika di Singapura. Persembahan ini desiccants komposit ditanda aras dengan prestasi gel silika tulen - bahan pengering yang paling biasa digunakan dalam pasaran hari ini. Diperhatikan, uji kaji, yang menggunakan bahan pengering komposit empat lapisan yang terdiri daripada silika gel (SiO2), Bentonit, Lithium Chloride (LiCl), dan Kalsium Klorida (CaCl2), telah membolehkan lebih besar penyingkiran kapasiti kelembapan bagi mengubah suhu udara masuk dan kelembapan antara 25 hingga 35oC dan 55 hingga 95% kelembapan relatif (RH). Peningkatan peratusan, berbeza dengan gel silika tulen, 14 ke 22.5%, dan 10 hingga 26.3% bagi mengubah masuk suhu udara dan berbeza-beza masuk RH, masing-masing.