Suchergebnisse

AbstractBiowaste treatment with Black Soldier Fly (BSF) larvae is an alternative option for organic waste valorization. Its environmental impacts should be assessed and compared with conventional treatment options. The research aims to evaluate the treatment of organic fraction of municipal solid waste (OFMSW) with BSF larvae through a life cycle assessment (LCA). This study employed data inventories from literature and aimed to provide a wide range of production parameter values to identify the potentialities of BSF treatment in the best-case and worst-case scenarios. The SimaPro9, the database Ecoinvent3.5, and the impact assessment method IMPACT 2002+ have been employed for the analysis. A sensitivity analysis of relevant parameters was conducted, considering the avoided impacts that can be obtained thanks to the exploitation of larvae proteins for bioplastics or fishmeal production. Research findings highlight six main environmental impact indicators: respiratory inorganics (kg PM2.5-eq), ozone layer depletion (kg CFC-11-eq), terrestrial ecotoxicity (kg TEG soil), land occupation (m2 organic arable), global warming (kg CO2-eq), and non-renewable energy (MJ primary). The most relevant process generating impacts is BSF breeding, followed by boiling, storage, and OFMSW treatment. The environmental performance is better when the conventional fishmeal substituted, thanks to BSF larvae production, is made from areas 10,000 km far, implementing a 100% renewable energy scenario, reducing the energy consumption by 50%, increasing the lifespan of the equipment to 15 years, and products are employed locally. The current study represents the first attempt to evaluate the global higher or lower environmental impact scenario related to OFMSW treatment through BSF larvae.
Graphical Abstract

AbstractIn Bolivia, construction and demolition waste (CDW) is unmanaged. The current research implemented a CDW flow analysis and a cost assessment in the city of La Paz, aiming to compare future recycling scenarios. Lack of data is challenging; therefore, a review of 31 international studies has been conducted. Results report that the waste generation rate (WGR) of concrete residential buildings can be of about 91.9–113.3 kg m−2 for construction and about 867.2–1064.8 kg m−2 for demolition. In addition, positive correlation was found in national WGR with number of inhabitants and the GDP. By these results, it was estimated that about 271,051–349,418 tonnes of CDW are potentially generated yearly in La Paz, about two times more than the CDW projected by local authorities. By the scenarios analysis, it was estimated that 56.1–71.1% of the inert aggregates can be recycled. The cost of the system is estimated between 7.8 and 31.1 USD tCDW−1, for a total annual cost (20 years horizon) of about 2.3–9 million USD y−1 depending on the management scenario. In the best scenario, an average fee of less than 1% of the current costs of a flat in La Paz can be required, potentially affordable for the local economy. The most attractive scenario involves the source separation of recyclable materials and the hybrid organization of stationary and mobile recycling facilities. Results show that a CDW management can be implemented in La Paz to foster a circular economy in developing cities.