Microwave Pyrolysis of Organic Wastes for Syngas-Derived Biopolymers Production

Chemical Engineering Journal

Monti

Kostas

et al. 2017

Self Cite

176

The pursuit of sustainable hydrocarbon alternatives to fossil fuels has prompted an acceleration in the development of new technologies for biomass processing.Microwave pyrolysis of biomass has long been recognised to provide better quality bio-products in shorter timescales compared to conventional pyrolysis. Although this topic has been widely assessed and many investigations are currently ongoing, this article gives an overview beyond the physico-chemical pyrolysis process and covers engineering aspects and the limitations of microwave heating technology. Herein, we provide innovative scalable concepts to perform the microwave pyrolysis of biomass on a large scale, including essential energy and material handling requirements. Furthermore, some of the possible socio-economic and environmental implications derived from the use of this technology in our society are discussed. Such potential concepts are expected to assist the needs of the industrial bioenergy community to move this largely studied process upwards in scale.

Section: Environmental Impact and Sustainabilitymentioning

confidence: 99%

Microwave pyrolysis of biomass for bio-oil production: Scalable processing concepts

Chemical Engineering Journal

Monti

Kostas

et al. 2017

Self Cite

176

“…heating. This process benefits from the main advantages of using microwaves, such as rapid, volumetric and selective heating, and avoids the need to shred the feedstock and to pre-dry the samples, resulting in a substantial reduction in the costs associated with these steps [2][3][4][5]. In spite of these advantages, this technology has not yet reached industrial scale owing to the lack of economic analyses on a large scale and the absence of sufficient data to quantify the dielectric properties of the input feedstocks.…”

Section: One Of These New Technologies Is Microwave Pyrolysis Based Omentioning

confidence: 99%

Dielectric characterization of biodegradable wastes during pyrolysis

Albero-Ortiz

Monzó‐Cabrera

et al. 2016

Fuel

Self Cite

11The lack of dielectric properties data has often been named as one of the 12 reasons that has hampered the simulation of microwave processing of 13 biomass feedstock and process design. In this work, the dielectric behavior 14 of an organic fraction from municipal solid wastes during pyrolysis has been 15 monitored as a function of temperature. Furthermore, the effect of the 16 addition of a microwave absorbent material (carbonaceous char) to the raw 17 biowaste upon the dielectric properties has been investigated for the first 18 time. 19The efficiency of the conversion of microwave energy to heat, measured by 20 means of the tan δ parameter, is shown in this study to be nearly 20 times 21 higher when the absorbent char is added to the reaction bulk at room 22 temperature and this gap is even greater in the 600 -800 ºC range. 23Nevertheless, the results suggest that the addition of increasing amounts of 24 microwave absorbent (up to ca. 40%) impairs microwave penetration, which 25gives rise to a less homogeneous heating of the bulk. There is therefore an 26 optimum proportion that balances heat conversion and penetration depth. 27The results of this study lend support to the use of char as a means to 28 induce thermochemical treatments by microwaves and reduce energy 29 consumption in the process. 30 31

“…The production of syngas from biomass and organic wastes is mainly accomplished by means of gasification processes (Mahinpey and Gomez, ), although new emerging thermal conversion technologies, such as the microwave‐induced pyrolysis (MIP) has been reported as an effective and greener way to increase the waste conversion to H 2 and CO (Budarin et al ., ; Beneroso et al ., , , ,b,c). The attractiveness behind MIP is the fact that microwaves are able to induce an instantaneous and volumetric heating within the samples and thus, overcoming heat transfer constraints as a result of the low thermal conductivity of biomass and biowastes (Beneroso et al ., ; Beneroso and Fidalgo, ).…”

Section: Introductionmentioning

confidence: 99%

Syngas obtained by microwave pyrolysis of household wastes as feedstock for polyhydroxyalkanoate production inRhodospirillum rubrum

Revelles

Microbial Biotechnology

Menéndez

et al. 2016

SummaryThe massive production of urban and agricultural wastes has promoted a clear need for alternative processes of disposal and waste management. The potential use of municipal solid wastes (MSW) as feedstock for the production of polyhydroxyalkanoates (PHA) by a process known as syngas fermentation is considered herein as an attractive bio‐economic strategy to reduce these wastes. In this work, we have evaluated the potential of Rhodospirillum rubrum as microbial cell factory for the synthesis of PHA from syngas produced by microwave pyrolysis of the MSW organic fraction from a European city (Seville). Growth rate, uptake rate, biomass yield and PHA production from syngas in R. rubrum have been analysed. The results revealed the strong robustness of this syngas fermentation where the purity of the syngas is not a critical constraint for PHA production. Microwave‐induced pyrolysis is a tangible alternative to standard pyrolysis, because it can reduce cost in terms of energy and time as well as increase syngas production, providing a satisfactory PHA yield.