A review of the potential of pretreated solids to improve gas biofuels production in the context of an OFMSW biorefinery

Abstract

The organic fraction of municipal solid waste (OFMSW), mainly composed of lignocellulosic polymers, is extremely complex. Therefore, it is necessary to apply pretreatments to remove the lignin content and decrease the cellulose crystallinity in order to use the OFMSW for gas biofuels production in the context of biorefineries from waste. This work focused on critically reviewing the conventional pretreatments applied to OFMSW, with the goal of improving the H 2 production, as well as other biofuels in modern biorefineries. There are a wide variety of pretreatments that have successfully been used, mainly alkaline, milling and dilute acid. In addition, some research has focused on the recovery and reutilization of the alkali, acid or solvents after the pretreatment, to be incorporated into new cycles of production, minimizing the environmental impacts. Moreover, it would be necessary to incorporate analytical tools, in order to determine the sustainability of the biorefinery project. It is concluded that waste pretreatments could significantly contribute to increased yields of biogas fuels in organic waste-based biorefineries. Therefore, establishing preliminary stages for conditioning biomass or wastes is essential to improve the degradation of wastes and bio-product generation. 938 www.soci.org L Romero-Cedillo et al. db dry basis wb wet basis wrm wet reactor mass J Chem Technol Biotechnol 2017; 92: 937-958 /jctb , [56.76 j , 2.53 k ] 104 J Chem Technol Biotechnol 2017; 92: 937-958 Steam explosion Steam explosion, also known as hydrothermal, promotes the formation of soluble lignin compounds, such as HMF, due to high temperatures that stimulate the breakdown of sugars. 121 In this process, HMF and other inhibitor compounds are generated, such as furans from pentoses and HMF from hexoses. 122 Interestingly, HMF can be finally degraded into levulinic and formic acids. In contrast, even when a pretreatment did not necessarily remove lignin, it was hypothesized that high temperatures had a significant J Chem Technol Biotechnol 2017; 92: 937-958 /jctb J Chem Technol Biotechnol 2017; 92: 937-958

Evaluation of feeding strategies in upflow anaerobic sludge bed reactor for hydrogenogenesis at psychrophilic temperature

“…Perera et al [55] arrived to similar observations than ours, arguing that the improvement in hydrogen production at temperatures above 25 °C is not defensible as net energy gains were negative and declining as temperature increased. Moreover, other strategies to increase the energetic gains of psychrophilic biohydrogen production would be by its coupling to other bioenergy processes such as microbial fuel cells, photofermentation and anaerobic digestion, among others [56][57][58][59].…”

3-Routes Platform for Recovery of High Value Products, Energy and Bio-Fertilizer From Urban Biowaste: The Revenue Project

“…Mild thermal pretreatment can, in fact, significantly alter both physical and chemical properties of FW, resulting generally in increased solubilization (Pagliaccia et al, 2016(Pagliaccia et al, , 2019Montecchio et al, 2017), in reduced lignocellulosic matrix, and improved digestate hygienization (Ariunbataar et al, 2015). Cellulose, hemicellulose and lignin containing wastes as OFMSW (source separated organic fraction) and FW (Romero-Cedillo et al, 2017), need further pretreatment in order to make the substrate more accessible to microbial degradation (Loow et al, 2016). Pecorini et al (2016) reported increase of soluble COD, carbohydrates and proteins concentration in the pretreated OFMSW sample, while lignocellulosic and starch fraction were found to be lower in the pretreated FW by Pagliaccia et al (2019).…”

Biorefinery concept comprising acid hydrolysis, dark fermentation, and anaerobic digestion for co-processing of fruit and vegetable wastes and corn stover

“…The sources of biomass for biorefineries are numerous and in order to not compromise the food supply, biowastes should be mainly used as its substrates (Romero-Cedillo et al 2016). Considering that Mexico was the 11 th agriculture producer worldwide with an annual production of 210 million tons in 2018 (SADER 2019), its wastes generation along the food supply chains (production, postharvest, processing, distribution, consumption) are also considerable.…”