نوع مقاله : مقاله پژوهشی
نویسندگان
1 گروه مهندسی مکانیک بیوسیستم، دانشکده کشاورزی، دانشگاه رازی، کرمانشاه، ایران
2 گروه مهندسی بیوسیستم، دانشکده کشاورزی، دانشگاه تبریز، تبریز، ایران
چکیده
کلیدواژهها
موضوعات
عنوان مقاله [English]
نویسندگان [English]
Introduction
Energy, as one of the most critical and essential factors of production, plays a vital role in human life. With fossil fuel resources depleting, researchers are exploring alternatives such as biodiesel, a renewable biofuel with properties similar to diesel. Given the growing importance of liquid biofuels, particularly biodiesel, in global markets, it is crucial to ensure high-quality fuel production to gain consumer trust. Additionally, from a commercial perspective, considering fuel storage duration, it is necessary to determine the type of fuel and the biodiesel-to-diesel ratio using accurate, fast, and cost-effective tools.
Materials and Methods
This study aims to identify and differentiate various blends of biodiesel and diesel fuel (2%, 5%, 10%, and 20% by volume) derived from different vegetable oil sources (rapeseed, sunflower, and waste cooking oil) over different storage periods (immediately after production, 1 month, 2 months, and 3 months after production). Biodiesel was first produced from rapeseed oil, sunflower oil, and waste cooking oil using methanol and a potassium hydroxide (KOH) catalyst. Each biodiesel blend was mixed with diesel fuel at the specified ratios and analyzed using an electronic nose system equipped with 10 sensors. Data were collected over different periods (monthly) and analyzed using methods such as linear discriminant analysis (LDA), quadratic discriminant analysis (QDA), and support vector machine (SVM).
Results and Discussion
The results demonstrated the effectiveness of classification methods in separating pure fuels over four months. The accuracy rates were 97%, 100%, 82%, and 82% for SVM; 100%, 100%, 100%, and 98% for QDA; and 100%, 96%, 100%, and 100% for LDA, respectively. These methods were also capable of distinguishing pure fuels (D100, K100, WCO100, SUN100) from biodiesel-diesel blends at various storage times with high precision.
Among the sensors in the system, four sensors (MQ2, TGS2620, MQ4, and TGS2602) showed the highest sensitivity to biodiesel fuels. The analysis revealed that the separation power of the models decreased during the second month of storage, with the lowest performance observed after two months. This suggests that the most significant structural and physicochemical changes in biodiesel properties occurred during this period. Furthermore, the similarity in performance parameters for fuels derived from sunflower oil and waste cooking oil indicates their shared origin.
The QDA model outperformed the LDA and SVM models in separating and classifying fuel blends. Using the SVM technique, all 160 data points (40 for pure fuel and 120 for biodiesel-diesel blends) were evaluated. The SVM model achieved a specificity of over 96% for identifying and classifying pure and blended fuels immediately after production. This parameter increased to 94%, 98%, and 99% after the first, second, and third months of storage, respectively.
Conclusion
The study highlights the effectiveness of electronic nose systems combined with advanced classification methods for analyzing biodiesel-diesel blends. The QDA model demonstrated superior performance in fuel classification, while the SVM model also showed high accuracy in distinguishing pure and blended fuels. The findings underscore the importance of monitoring fuel quality over storage periods, as significant changes occur within the first two months.
Acknowledgment
This research is based on the results of a master's thesis conducted at Razi University. The authors extend their gratitude to the university officials for providing the necessary facilities and support to carry out this study.
کلیدواژهها [English]
)