Backtracking search algorithm in CVRP models for efficient solid waste collection and route optimization.
Waste collection is an important part of waste management that involves different issues, including environmental, economic, and social, among others. Waste collection optimization can reduce the waste collection budget and environmental emissions by reducing the collection route distance. This paper presents a modified Backtracking Search Algorithm (BSA) in capacitated vehicle routing problem (CVRP) models with the smart bin concept to find the best optimized waste collection route solutions. The objective function minimizes the sum of the waste collection route distances. The study introduces the concept of the threshold waste level (TWL) of waste bins to reduce the number of bins to be emptied by finding an optimal range, thus minimizing the distance. A scheduling model is also introduced to compare the feasibility of the proposed model with that of the conventional collection system in terms of travel distance, collected waste, fuel consumption, fuel cost, efficiency and CO2emission. The optimal TWL was found to be between 70% and 75% of the fill level of waste collection nodes and had the maximum tightness value for different problem cases. The obtained results for four days show a 36.80% distance reduction for 91.40% of the total waste collection, which eventually increases the average waste collection efficiency by 36.78% and reduces the fuel consumption, fuel cost and CO2emission by 50%, 47.77% and 44.68%, respectively. Thus, the proposed optimization model can be considered a viable tool for optimizing waste collection routes to reduce economic costs and environmental impacts.
Dept of Civil & Structural Engineering, Universiti Kebangsaan Malaysia, 43600 Bangi, Malaysia. Electronic address: mahmuda@siswa.ukm.edu.my.
Mahmuda
M
Akhtar
Dept. of Electrical Power Engineering, College of Engineering, Universiti Tenaga Nasional, 43000 Kajang, Malaysia. Electronic address: hannan@uniten.edu.my.
M A
MA
Hannan
Institute of Climate Change, Universiti Kebangsaan Malaysia, 43600 Bangi, Malaysia. Electronic address: rawshan@ukm.edu.my.
R A
RA
Begum
Dept of Civil & Structural Engineering, Universiti Kebangsaan Malaysia, 43600 Bangi, Malaysia. Electronic address: drhb@ukm.edu.my.
Hassan
H
Basri
Dept of Electrical, Electronic and Systems Engineering, UKM, 43600 Bangi, Malaysia. Electronic address: scavino@ukm.edu.my.
Edgar
E
Scavino
D000465:Algorithms; D002245:Carbon Dioxide / Q000032:analysis; D008962:Models, Theoretical; D018986:Motor Vehicles; D012037:Refuse Disposal / Q000379:methods*; D062611:Solid Waste
D062611:Solid Waste; D002245:Carbon Dioxide
BSA; CVRP model; Route optimization; Threshold waste level; Waste collection