改良式傾斜循環流體化床應用於吸附除濕系統

Performance Improvement of Circulating Inclined Fluidized Bed Applied to Desiccant Dehumidification Systems

洪泰智(Tai-Chih Hung)

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(2016年)

https://doi.org/10.6342/NTU201603224

摘要

本研究之目的為設計一傾斜式循環流體化床系統，此系統透過重力、垂直於床體的顆粒通道與流體化特性即可連續操作，無須採用漏斗及轉彎接頭。首先，本研究以操作風速3 m/s，吸附床入口空氣溫度27℃、相對濕度70%與再生床入口空氣溫度50℃的條件進行垂直式循環流體化床與傾斜式循環流體化床之比較，使用平均粒徑為4 mm的矽膠顆粒1100 g之改良式傾斜循環流體化床相較傾斜循環流體化床提升吸附能力6.8%，壓損下降10.6%，風機耗電量減少11.8%，所以改良式傾斜循環流體化床適合用於空調除濕系統。
其次，更進一步變動改良式傾斜循環流體化床之幾何參數後，再生底座高度不變及吸附床顆粒通道於床體20 cm處時，整體吸附能力提升16%。且進行模擬2014台北全年外氣條件，全年吸附量達到729.5 kg，相較傾斜循環流體化床除濕量提升至14.1%。而當吸附床入口溫度30℃、相對濕度80%與再生床溫度50℃，使用混合顆粒於改良式傾斜循環流體化床，相對使用矽膠顆粒的情況下，吸附能力略低於11.6%，混合顆粒較不適用於循環除濕系統上。最後，當床體的角度改為10°時，可以增加除濕量5.7%，但系統無法於長時間下穩定運作。

關鍵字

傾斜式循環流體化床 ； 循環 ； 吸附除濕 ； 矽膠 ； 高分子

並列摘要

The purpose of this study is to design a inclined circulating fluidized bed that maintains a healthy indoor environment and be energy-efficient. With gravity, the design of particle channels vertical to the bed and the characteristics of the fluidized bed. The system can adsorb water continuously without funnel and corner joints.
First, compared to the circulating inclined fluidized beds device. The total adsorption amounts of circulating improved inclined fluidized bed increased by 6.8% when the air speed was 3 m/s, the entrance air temperature was 27℃and relative humidity was 70% in the adsorption bed, the entrance air temperature was 50℃in the desorption bed , and filled with 4mm diameter silica gel, total weight 550 g, in each bed. Under this condition, the pressure loss and the energy consumption of fan reduced by 10.6% and 11.8% respectively. The result indicated that the circulating improved inclined fluidized bed has better dehumidification performance than the circulating inclined fluidized bed.
Second, changed the geometric parameters of the circulating improved inclined fluidized bed. Maintain the high of desorption bed base and adjust particle channels to 20 cm high of the adsorption bed, accordingly, the total adsorption amounts increased by 16%. Further, simulation ambient air conditions at Taipei 2014 annual. The total adsorption amounts was 729.5 kg , compared to the circulating inclined fluidized beds device, the dehumidification performance of circulating improved inclined fluidized bed increased by 14.1%
When the entrance air temperature was 30℃and relative humidity was 80% in the adsorption bed, the entrance air temperature was50℃ in the desorption bed, compared to the circulating improved inclined fluidized beds device with silica gel, the adsorption capacity of particles mixed with silica gel and polymer was lower than silica gel 11.6%. The result indicated that silica gel has better particles mixed with silica gel and polymer.
Last, the dehumidification will increase 5.7% when inclined circulating fluidized bed adjust to 10°, but this system can not maintaining stability in a long time.

並列關鍵字

circulating Inclined Fluidized Bed ； circulating ； desiccant dehumidification ； polymer ； silica gel

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