本研究針對桃園地區以煤炭為燃料之固定污染源為研究對象，分為大型及中小型鍋爐兩大類，分析並比較其歷年污染排放量變化，以了解不同規格鍋爐及防制設備對粒狀污染物、硫氧化物及氮氧化物排放量的差異。第二部份則為實地進行燃煤鍋爐廢氣進入防制設備前及排放管道排放之濃度比較，以確認其去除效率及防制設備操作參數的差異，作為環保主管機關日後行政管制及鍋爐使用者日常操作之參考。 排放量分析結果，大型燃煤鍋爐由於受環評及較嚴排放標準限制，裝設防制設備包括靜電集塵器、濕式排煙脫硫及選擇性觸媒還原等，除部份用煤量記錄有異及混合其他燃料燃燒者外，多數排放狀況均能符合現行排放標準及其他相似規模污染源排放狀況；中小型燃煤鍋爐則因排放標準仍較寬鬆故防制設備亦參差不齊且檢測結果及排放量高低差異較大。大型汽電鍋爐平均硫氧化物排放係數為0.42(kg/ton)、氮氧化物排放係數平均為0.41~1.58(kg/ton)。 燃煤鍋爐防制設備效率檢測結果顯示A廠及B廠對粒狀污染物之去除效率平均達94.87%，高於C廠及D廠平均64.16%，在中小型燃煤鍋爐使用旋風分離器已可達到相當良好之粒狀污染物去除效率但在較大廢氣量時去除效率明顯下降；硫氧化物去除效率中以D廠洗滌器對硫氧化物去除效率達93.82%最高，該廠之洗滌液流率與液氣比為四廠最高，顯示硫氧化物之去除主要受洗滌液流率及液氣比影響，氮氧化物由於對水的溶解度低，去除效率與燃料用量及洗滌塔操作條件並無相關性。 This research takes the fixed coal fired pollution source located in Tao-yuan area as the object of study. It sorts out 2 types of boilers as large-scale and medium/small ones for comparing its historical records of emission to find out the variation of emissions created by different sizes of boilers and control equipment. Second part of the study is based on on-job site research of stack emission from coal-fired boilers and its intensity for affirming the difference of efficiency of control equipment and operating parameter. The results obtained will provide reference data for environmental protection administration to take regulatory control and boiler-user’s daily operation. According to the emission analysis of stack gases, because of the requirement of Environment Impact Assessment and stricter restriction of flue gas emission standard, large-scale coal-fired boilers are generally equipped with efficient control facilities including electrostatic precipitator (EP), flue-gas desulfurization (FGD), and selective non-catalytic reduction (SNCR), and most of big-size boilers can meet current emission standards. As far as medium/small size of coal- fired boilers are concerned, in view of less stringent emission standard, their control equipment are generally less effective and the results exhibit larger variation of emissions. The average emission factor of SOx for co-generation boilers is 0.42 (kg/ton coal burned) and the emission factor of NOx is 0.41-1.58 (kg/ton coal burned). The results obtained reflect that the removal efficiencies of control equipment for particulate matter of coal-fired boilers of Plants A and B reach 94.87% in average which is higher than that of Plants C and D, being 64.16% in average. The cyclone shows good control efficiency of particulate matter in medium/small size of coal fired boiler but the efficiency decreases significantly as the gas flow rate increases. The removal efficiency of SOx reaches 93.82% at Plant D in which the control equipment of scrubber operated at the highest L/G ratio among the four plants investigated. However, no obvious relationship is found between the operating parameters and NOx removal efficiency possibly due to the low solubility of NOx in scrubbing liquid.
