Proof of concept of high-rate decentralized pre-composting of kitchen waste: Optimizing design and operation of a novel drum reactor. (15th May 2019)

• Record Type: Journal Article
• Authors: Sakarika, Myrsini; Spiller, Marc; Baetens, Robin; Donies, Gil; Vanderstuyf, Jolan; Vinck, Kathleen; Vrancken, Karl C.; Van Barel, Gregory; Du Bois, Els; Vlaeminck, Siegfried E.
• Is Part Of: Waste management. Volume 91(2019)
• Page Start: 20
• Page End: 32
• Publication Date: 2019-05-15
• Subjects: Food waste -- Organic household waste -- Water removal -- Community scale -- Source separation -- Circular economy; KW kitchen waste -- FKW formulated kitchen waste -- RKW real kitchen waste -- OHW organic household waste -- FW fresh weight -- PE person equivalents -- EC electrical conductivity -- TS total solids -- VS volatile solids -- FS fixed solids -- TSS total suspended solids -- VSS volatile suspended solids -- OC organic carbon -- COD chemical oxygen demand -- BOD5 5-day biochemical oxygen demand -- TKN total Kjeldahl nitrogen -- TP total phosphorus -- VFA volatile fatty acids; Hazardous wastes -- Periodicals; Refuse and refuse disposal -- Periodicals; 363.728
• DOI: 10.1016/j.wasman.2019.04.049
• Languages: English
• ISSNs: 0956-053X

Abstract

Graphical abstract: Highlights: A high-rate prototype reactor (200L) to pre-compost kitchen waste was built. Kitchen waste mass and volume reductions of 33%FW and 62% were achieved. Results indicate a mean total cost of €11, 600 per urban pre-composter over 10 years. Final compost with a C/N ratio of 12 was produced from pre-compost in 54 days. No addition of bulking agents or separate leachate collection was required. Abstract: Each ton of organic household waste that is collected, transported and composted incurs costs (€75/ton gate fee). Reducing the mass and volume of kitchen waste (KW) at the point of collection can diminish transport requirements and associated costs, while also leading to an overall reduction in gate fees for final processing. To this end, the objective of this research was to deliver a proof of concept for the so-called "urban pre-composter"; a bioreactor for the decentralized, high-rate pre-treatment of KW, that aims at mass and volume reduction at the point of collection. Results show considerable reductions in mass (33%), volume (62%) and organic solids (32%) of real KW, while provision of structure material and separate collection of leachate was found to be unnecessary. The temperature profile, C/N ratio (12) and VS/TS ratio (0.69) indicated that a mature compost can be produced in 68 days (after pre-composting and main composting). An economic Monte Carlo simulation yielded that the urban pre-composter concept is not more expensive than the current approach, provided its cost per unit is €8, 000–€14, 500 over a 10-year period (OPEX and CAPEX, in 80% of the cases). The urban pre-composter is therefore a promising system for the efficient pre-treatment of organic household waste in an urban context.