sustainable waste management alternatives have been emerged and compared to the commonly used SWM

scenario (landfills). The scenario included, collection and transportation of waste, material recovery facility

(MRF), AD, and landfilling processes. WRATE software databases were used to obtain data for the life cycle

inventory (LCI). The functional unit has been selected as the management of 1 ton of MSW for a study period

of 20 years. The scenarios were evaluated via the CML 2001 impact assessment method covering 6 categories

including climate change, eutrophication potential, acidification potential, freshwater aquatic ecotoxicity,

human toxicity, and resource depletion. The findings revealed that the proposed strategy improved the life

cycle environmental performance in all impact categories and resulted in significant economic savings.

Keywords: - Anaerobic Digestion; Organic Waste Management; Life Cycle Assessment; Life Cycle Costing,

organic waste. According to the 5th Assessment

Report of the Intergovernmental Panel on Climate

Change (IPCC), methane has 28 times the global

warming potential (GWP) of carbon dioxide over a

100-year time horizon, [1]. A preliminary analysis

carried out by the National Oceanic and

Atmospheric Administration (NOAA) indicated 17

parts per billion (ppb) annual increase in

atmospheric methane during the year 2021, the

largest increase in methane concentration since 1983

reducing the amount released into the atmosphere.

Recycling, climate change, and socioeconomic

benefits can be achieved with small-scale biowaste

treatment plants because of low transportation costs,

adaptability to mass changes, high-quality products,

solution compared to landfilling in terms of using

biomass as fuel which can reduce greenhouse gas

emissions. Coventry et al. (2016) also utilized LCA

to compare four different solid waste treatment

scenarios including dry-tomb landfill, landfill gas to

energy, advanced thermal recycling, and

gasification in the U.S. Cities. The findings revealed

that the majority of the environmental impacts were

organic fraction of MSW, and thermal treatment of

the residual waste. The results of this study show

that implementing recycling practices enhanced the

overall environmental performance. Few more

studies evaluated the impacts of utilizing small-scale

SWM technologies. For example, [6] assessed the

impacts of SWM scenarios (including open dumps

and small-scale incinerators) implemented in

Greenland. The results revealed that the detrimental

effects were mainly due to air emissions from the

environmental and economic impacts of SWM

systems in terms of the life cycle approach. A study

by [9] evaluated different MSW management

scenarios, including AD, incineration, composting,

recycling, and landfilling in different Swedish

municipalities. The results revealed the applicability

of combined LCA and LCC methods, where both

analyses revealed higher environmental and

economic costs of landfilling. Similarly, [10]

for the collection and treatment of different waste

streams (e.g., mixed solid waste, biowaste, and

glass). The results revealed the energy recovery

potential and environmental benefits of the AD

system. The biogas plant resulted in total revenue of

USD 178,000/year. In addition, the recycling of the

digestate for agricultural applications was confirmed

via the characterization of the digestate which

wastes comprised 50, 15, 10, 10, and 15% of the

total MSW respectively, [13]. Fig. 1 shows the

examined waste management scenarios of this

study. The proposed waste management plan

includes collecting organics and non-organics in

dual bins where organic waste is processed in AD,

and non-organics are dispatched to MRF since

material recycling is a substantial pillar of

common waste management practice in developing

countries of landfilling MSW from several

sustainability perspectives.

depend on energy generation potential of AD

facility; retrieved from [18].

value aggregating all the midpoint categories. On

the other hand, NPV was utilized as the economic

indicator for the examined scenarios. An eco-

efficiency portfolio combining the environmental

and economic scores was plotted for the selection of

the most eco-efficient system taking into

consideration the trade-off among the studied

alternatives.

3 Results and Discussion

3.1 Life Cycle Assessment

higher energy generation efficiency and lower gas

leakage potential of AD systems. Moreover, the

from the sales of baled materials in MRFs and

digestate in AD. Although anaerobic digesters have

high capital costs, combining such a facility with

MRF would increase the cost-savings due to the

high revenue from selling the generated electricity

associated with AD. MRF was incorporated in the

proposed scenario as material recovery plays an

essential role in sustainable waste management.

management scenarios.

Fig. 2 depicts the cumulative NPV and the expected

payback periods for the selected management

scenarios over the 20 years assessment period. The

payback periods for the proposed system were

found to be around 8 years, while the conventional

environmental performance ratios were plotted

in an eco-efficiency portfolio as illustrated in

Fig. 3. The scenarios can be evaluated in terms

of low and high eco-efficiency according to the

relative eco-efficiency score. The conventional

waste management system was characterized by

high environmental impacts and significant

economic losses. On the other hand, the

decentralized AD-based system has proven to

be eco-efficient compared to the conventional

[1] H. Zhao, N. J. Themelis, A. Bourtsalas, and

[2] NOAA, “Increase in atmospheric methane

[22] ISO 14045, “Environmental management—

[25] M. Koskela and J. Vehmas, “Defining Eco-