高功率直流電漿火炬電極熔蝕之研究

A Study on Electrode Erosion of High-Power DC Plasma Torch

林登連(Deng-Lain Lin)

指導教授 ： 張義鋒 ； 趙修武

中原大學/工學院/機械工程研究所/碩士(2003年)

https://doi.org/10.6840/cycu200300009

摘要

高功率直流電漿火炬為電漿處理廢料技術的心臟，如何減低電極熔蝕率，增長使用壽命，為電漿火炬工業應用的重要課題。本研究依直流電漿的工作原理、設計要點，設計製作了一套100仟瓦非傳輸型直流電漿火炬實驗系統，用以研究外加磁場、電流、工作氣體流量等參數對火炬電極熔蝕率的影響。同時藉由STAR-CD數值計算軟體進行未加能量的流場分析，做為設計改良之參考依據。實驗結果顯示：當電流為160安培、氣體流量為650sL/min及磁場強度為200高斯時，火炬電極之平均相對熔蝕率最低，經選取一組相對熔蝕率低的火炬操作條件，進行100小時運轉測試總電極熔蝕量，校正計算出火炬的絕對熔蝕率為 克/庫倫(0.63克/小時)，並藉以計算出各操作條件之電極絕對熔蝕率。本研究經由管型電漿火炬運轉機制的探討，得以抑低電極熔蝕率，100仟瓦非傳輸型直流電漿火炬後電極的使用壽命預估大於300小時。

關鍵字

電漿火炬 ； 電漿處理廢料技術 ； 電極熔蝕率

並列摘要

High power plasma torch is the heart of plasma waste processing technology. How to reduce the erosion rate of electrode and to increase the lifetime of torch electrodes becomes to an important issue for the industrial applications of the plasma torch technology. To study the effects of the applied magnetic field, torch current and flow rate of working gas on the erosion rate of torch electrode, a 100kw plasma torch system was designed, fabricated and adapted with an optical detection system. The torch flow pattern was simulated by STARD-CD computer code for the reference of torch design. The experimental results show that the rear electrode reach to the lowest erosion rate when the plasma is operated with conducting current of 160 A, working gas flow rate of 650 sl/min and external magnetic field of 200 gauss. To calibrate the absolute erosion rate of torch electrode, the plasma torch system was continuous operated for 100 hours. The absolute electrode erosion rate was calculated as the quotient of electrode weight loss and total charge through electrode after 100 hours operation. The absolute erosion rate of the torch electrode under above conditions is about 1.1×10-6 g/C (0.63g/hr). Accordingly, all the absolute electrode erosion rates under other conditions can be calculated. The operation mechanism of tubular plasma torch was studied, and the erosion rate of torch electrode could be minimized. The rear-electrode lifetime of the 100kw plasma torch is estimated as above 300 hours, which can meet the requirement of industrial applications.

並列關鍵字

Plasma torch ； Plasma waste processing technology ； Electrode erosion

參考文獻

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