水泥製造業是一重要基本工業，也是帶動國家民生、交通、國防等相關工業發展之基礎；但另一方面，水泥製造業卻是一極為耗能、污染量大之工業，因此在國人生活水平提高、環保意識抬頭之後，水泥廠更成為民眾陳情抗爭之主要對象之一。以往民眾對於水泥廠關切的是其逸散粉塵問題，造成空氣中粒狀污染物濃度增高，嚴重影響環境空氣品質；但在各廠陸續裝設靜電集塵器等集塵設施，並將其視為水泥廠的標準配備後，逸散粉塵問題已獲得長足改善。 然而，水泥製造業之旋窯須以1,400℃以上高溫燒結，並燃燒煤炭作為燃料，產生大量之氮氧化物（NOX）與二氧化碳（CO2）二類污染物，前者為臭氧（O3）及酸雨之前趨物，後者為溫室效應氣體，均為現今國際間最為關心的空氣污染物。因此，本研究乃針對水泥製造業產生NOX與CO2之排放問題進行探討，透過文獻回顧、污染物監測分析資料以及質量平衡計算等方式，進行台灣地區水泥業NOX及CO2排放係數之推估，同時並估算污染物之排放量，提供政府作為業別管制之參考。 本研究第二部份則是探討水泥製造業可行之DeNOX設施，由製程改善與管末處理二方式進行介紹。並選定花蓮一家水泥廠，實廠進行SNCR操作測試，透過CEMS自動連續監測系統，了解尿素噴注量與NOX削減量之關係，探討SNCR之處理效率；同時並分析尿素噴注量與其價格，以及空污費徵收標準，評估水泥廠以SNCR處理之經濟效益。此研究結果將可提供國內水泥業者，作為評估設置DeNOX設施時之參考。 The cement manufacturing process is an important basic industry, which gives the fresh impetus to the people’s livelihood, public transportation and national defense. On the other hand, cement manufacturing process consumes large quantity of energy and causes serious pollution; and has become one of the main subjects for public protest since the residents’ living standard and eco-awareness are enhanced. The public used to concern the increased particulate matter concentration caused by dust emission from cement plants. This problem was eventually solved after effective dust collecting equipments such as electrostatic precipitator(EP) were installed and regarded as the standard facilities by cement plants. In the cement manufacturing processes, raw materials are calcined with coal as a fuel at the temperature over 1,400oC inside the rotary kiln, which generates large quantity of NOX(the precursor of O3 & acid rain) and CO2(the major greenhouse gas). The purpose of this study is to investigate NOX and CO2 emitted from cement plants. Through literatures review, analysis of CEMS(continuous emission monitoring system) data and mass balance calculation, this study has estimated the emission factors and quantities of NOX & CO2 from cement industry in Taiwan. Part II of this study is motivated to discuss the feasibility of DeNOX technologies for cement industry, including process modification and installation of air pollution control devices (APCD) in cement plants. A real SNCR(selective non-catalytic Reduction) process was taken as an example in one Hualian cement plant. CEMS data, this study analyzed the correlation between urea injection rate and NOX emission, to calculate the NOX reduction efficiency achieved with the SNCR. Based on the urea injection rate / cost, and the standard to impose air pollution fee, the economic effectiveness of applying SNCR process is evaluated. This study will provide the reference for domestic cement plants to evaluate the suitability of applying DeNOX technology.
