Multiobjective Mathematical Optimization Model for Municipal Solid Waste Management with Economic Analysis of Reuse/Recycling Recovered Waste Materials
Keywords:multiobjective mathematical optimization model, goal programming model, economic benefit, reuse/recycling recovered waste materials, budgetry provision, Abuja, Nigeria
Municipal solid waste management in developing countries like Nigeria did not consider benefits from reuse/recycling recovered waste materials during solid waste evacuation and disposal. The benefits from recovered waste materials mostly go to informal waste vendors and scavengers. This study developed a multiobjective mathematical programming model for waste evacuation and disposal, considering the benefits of reuse/recycling recovered waste materials. Data were collected from the Abuja environmental protection board (AEPB), personal interviews, and other stakeholders. The formulated model was solved using spreadsheet solver version 14.0. The study uses various daily budgetary provisions for solid waste evacuation and disposal at a 15% recovery level of solid waste materials to observe the responses of the model. The solution shows that at 71.5% recovery of reuse/recycling recovered waste material; no budgetary provision is required to evacuate and dispose of the waste at the collection centres. Benefits realized from recovered waste materials are sufficient to evacuate and dispose of the wastes. After a 71.5% level of recovery, the net benefit of $1,108.17 from recovered waste materials starts to accrue until the percentage recovery level reaches 100%. The volume of waste shifted to the disposal sites was reduced to 74.5 tons (i.e. unrecoverable waste material) which is 16.82% of the total waste generated per day, and 368.33 tons (83.18%) of waste materials were recovered. The study will give the policymakers viable information to aid proper planning while budgeting and controlling solid waste associated problems in the Abuja municipal area in particular and the country as large.