作業環境甲醛逸散之改善與管末防治技術研究

End-of-Pipe Control Technology and Reductions of Formaldehyde Emissions in the Workplace

甲醛是一種無色及有強烈刺激性氣味的氣體，易溶於水及醇醚，而其對人體的傷害主要是表現在嗅覺異常、刺激、過敏及肺功能異常等方面，排氣甲醛若沒有妥善處理，將會導致作業人員之健康受到甲醛之危害，去除排氣中所含甲醛氣體，為本研究之目標。
本研究係針對一家傢俱材料工廠，就其管道排放甲醛的收集效率與以水洗塔去除甲醛的最佳化操作參數進行探討。結果顯示，施工後該作業環境之甲醛濃度有時會出現未達廠方要求的控制值0.3 ppm，導致此結果之原因有作業區溫度、甲醛逸散面積及甲醛濃度梯度之變異以及半圍封方式集氣效率偏低，尚需輔以適當換氣。為符合廠方要求，宜有效控制作業場所之溫度（溫度越高，甲醛之逸散率越大）及制定人員作業SOP以有效控制甲醛之捕集效率。排氣甲醛之去除在符合經濟性條件下，最佳操作條件為雙塔串聯模式處理，並設計自動加藥系統維持其洗滌液pH值即可達到排氣甲醛最佳之去除率。

Formaldehyde is a colorless gas with a strong pungent smell, and it is easily soluble in water and alcohol ethers. Its harm to the human body is mainly manifested in an abnormal sense of smell, irritation, allergies, and abnormal lung function. Formaldehyde exposure harms the health of workers, and the removal of formaldehyde gas in exhaust fumes was the goal of this research.
This research focused on a furniture material factory. The efficiency of collecting formaldehyde discharged from pipes and the optimal operating parameters for formaldehyde removal using water washing are discussed herein. After construction, the concentration of formaldehyde in the working environment sometimes exceeded the control value of 0.3 ppm required by the factory. The reasons for this are variations in the operating area temperature, formaldehyde emission area, and formaldehyde concentration gradient and the low gas collection efficiency of the semi-enclosed method. Adequate ventilation was necessary. To meet manufacturer requirements, the temperature of the workplace should be effectively controlled（the higher the temperature, the greater the formaldehyde emission rate）, and standard operating procedures should be formulated for personnel operations to effectively control the efficiency of formaldehyde capture. The removal of formaldehyde from exhaust gases is economically feasible. The optimal treatment method is double-tower series treatment. The first stage involves using NaOCl as a washing liquid, adjusting the chlorine concentration to 600 mg/L, and adjusting the pH to 6.5 using sulfuric acid. In the second stage of the series, NaOH is used as the washing liquid, the pH is adjusted to 12.0 for double-tower series washing, and an automatic chemical dosing system is used to maintain the pH value of the washing liquid to achieve the optimal removal rate of exhaust formaldehyde.