title: Creating Economic Incentives for Waste Disposal in Developing Countries Using the MixAlco Process.
abstract: In rapidly growing developing countries, waste disposal is a major challenge. Current waste disposal methods (e.g., landfills and sewage treatment) incur costs and often are not employed; thus, wastes accumulate in the environment. To address this challenge, it is advantageous to create economic incentives to collect and process wastes. One approach is the MixAlco process, which uses methane-inhibited anaerobic fermentation to convert waste biomass into carboxylate salts, which are chemically converted to industrial chemicals and fuels. In this paper, humanure (raw human feces and urine) is explored as a possible nutrient source for fermentation. This work focuses on fermenting municipal solid waste (energy source) and humanure (nutrient source) in batch fermentations. Using the Continuum Particle Distribution Model (CPDM), the performance of continuous countercurrent fermentation was predicted at different volatile solid loading rates (VSLR) and liquid residence times (LRT). For a four-stage countercurrent fermentation system at VSLR = 4 g/(L∙day), LRT = 30 days, and solids concentration = 100 g/L liquid, the model predicts carboxylic acid concentration of 68 g/L and conversion of 78.5 %.
authors.affiliation: Artie McFerrin Department of Chemical Engineering, Texas A&M University, 1M2A Brown Engineering Building, 3122 TAMU, College Station, TX, 77843, USA. sklonkar@tamu.edu.
authors.forename: Sagar
authors.initials: S
authors.lastname: Lonkar
authors.affiliation: Artie McFerrin Department of Chemical Engineering, Texas A&M University, 1M2A Brown Engineering Building, 3122 TAMU, College Station, TX, 77843, USA.
authors.forename: Zhihong
authors.initials: Z
authors.lastname: Fu
authors.affiliation: Artie McFerrin Department of Chemical Engineering, Texas A&M University, 1M2A Brown Engineering Building, 3122 TAMU, College Station, TX, 77843, USA.
authors.forename: Melinda
authors.initials: M
authors.lastname: Wales
authors.affiliation: Artie McFerrin Department of Chemical Engineering, Texas A&M University, 1M2A Brown Engineering Building, 3122 TAMU, College Station, TX, 77843, USA.
authors.forename: Mark
authors.initials: M
authors.lastname: Holtzapple
mesh_terms: D018533:Biomass; D002264:Carboxylic Acids / Q000737:chemistry; D002482:Cellulose / Q000737:chemistry; D003906:Developing Countries; D005243:Feces / Q000737:chemistry; D005285:Fermentation; D006801:Humans; D012037:Refuse Disposal; D062611:Solid Waste; D014556:Urine / Q000737:chemistry
chemical_list: D002264:Carboxylic Acids; D062611:Solid Waste; D002482:Cellulose
keywords: Continuum particle distribution model; Humanure; Municipal solid waste; The MixAlco process