矽膠循環流體化床應用於吸附除濕系統之研究

Investigation of Silica Gel Circulating Fluidized Bed with Applications on Desiccant Dehumidification System

吳柏勳(Po-Hsun Wu)

指導教授 ： 陳希立

國立臺灣大學/工學院/機械工程學研究所/碩士(2014年)

https://doi.org/10.6342/NTU.2014.11235

摘要

本研究之目的為設計矽膠循環流體化床系統，包含吸附床與再生床兩床體，以期能夠作為連續吸附潮濕空氣中水分之用。藉由氣固流體化床氣體與固體間高質傳率以及床體性質等優點，在流體化床中填充矽膠顆粒作為吸附材。並設計顆粒通道，透過重力以及空氣帶動矽膠顆粒在兩床體間循環使得系統能夠連續對水分進行吸附與脫附。
本文藉由設計系統並且對於影響系統的性能參數分別進行實驗，以了解系統的基本性能，如：吸附與脫附能力，以及影響系統性能參數，如：風速、再生溫度等，對系統性能的影響。實驗在兩床體中分別填充540 g，平均顆粒直徑為4 mm的矽膠顆粒。風速範圍從4.0 m/s至6.0 m/s，再生溫度由40°C至60°C。實驗結果顯示，風速以及再生溫度的增加使得系統的吸附與脫附性能有很顯著的增加。
本研究亦對循環流體化床的設計參數改變進行實驗，如床體中收集顆粒的漏斗高度以及在床體中加入擋板改善顆粒在床體中的運動狀態。實驗結果顯示，漏斗高度的增加使得吸附水分的矽膠顆粒不易循環，減少系統的吸附與脫附性能。而加入擋板後，改善系統性能，使得系統吸附能力提升14 %。

關鍵字

流體化床 ； 循環流體化床 ； 吸附除濕 ； 矽膠 ； 吸附 ； 脫附

並列摘要

The purpose of this study is to design a silica gel circulating fluidized bed that can continuous adsorb water content from air. The system contains two fluidized beds, one is adsorption bed, the other is desorption bed. Gas-Solid fluidized bed has several advantages such as high heat and mass transfer rate and uniform bed properties. With filling silica gel particles as desiccant material in the bed, and design of particle channels to transport particles circulating between two fluidized beds, the system can adsorb water continuously.
This study designs a silica gel circulating fluidized bed system and experimentally investigates the adsorption and desorption performance of the system. The experiment was carried out under various conditions, such as air velocity and desorption air temperature. Each bed is filled with 540 g of silica gel particles which mean diameter is 4 mm. In experiment, air velocity is raised from 4.0 m/s to 6.0 m/s, and desorption temperature is raised from 40°C to 60°C. It was found that the performance of the system is increased with increasing of both air velocity and desorption air temperature.
This study further investigates the performance of the system under various designs. It was found that with increasing the height of particle channel, the performance of the system decreased. Furthermore, with placing an inclined plate into bed can increase the circulation rate of the sorbent. Hence the performance of the system was increased. This improvement can increase the water adsorbed by 14% compared to the original design.

並列關鍵字

fluidized bed ； circulating fluidized bed ； desiccant dehumidification ； silica gel ； adsorption ； desorption

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