The pretreatment of lignocellulosic biomass for its transformation first into carbohydrates and then from these, through fermentation processes, into biofuels and chemicals, often involves the use of high-temperature techniques. This produces compounds derived from degradation processes which are called "inhibitors" because they hinder the microbial fermentation processes. Generally, inhibitors are low molecular weight molecules, therefore volatile. Inhibitors are commonly removed by washing with water; however water also removes the soluble carbohydrates. In this work, a specific and innovative removal technique of these inhibitors is reported. The substrate is biomass pretreated by steam explosion. We started by creating a proof of concept (TRL 2-3) with which it was demonstrated how it was possible to detoxify a lignocellulosic substrate by exploiting the volatility of some classes of inhibitors. The method was validated and perfected in the laboratory (TRL 4) and subsequently demonstrated and qualified in a relevant environment, also from an industrial point of view, using commercial equipment operating continuously downstream of the 150 kg / h steam explosion pretreatment plant STELE installed in the ENEA Research Center in Trisaia (MT). A TRL 8 was therefore achieved, in line with what was hoped for by the PRIT (PRetrattamento Italiano) project, funded and implemented under the 2015 Industry program and in the context of which the research was conducted. Overall, 3 types of equipment have been designed, realized and tested: 1) Fixed bed reactor consisting of a jacketed glass tube (thermostatable) inside which the exploded material containing the inhibitors is confined. 2) Fluidized bed reactor consisting in a glass tube similar to the previous one but oscillating. In fact, at the same time as a flow of hot air, the tube is subjected to a vertical oscillation achieved by coupling with a connecting rod to an electric motor with a variable number of revolutions. 3) Pilot fluidized bed dryer.
Il pretrattamento di biomassa lignocellulosica per la sua trasformazione in biofuels e chemicals si basa su processi di trasformazione e separazione condotti a temperature relativamente elevate. Generalmente possono essere prodotte molecole aventi un effetto inibitorio rispetto ai successivi processi di fermentazione. Questi inibitori sono abbastanza facilmente allontanati mediante lavaggi con liquidi che però rimuovono anche i carboidrati solubili. Considerando che gli inibitori sono per lo più molecole a basso peso molecolare, è nata l’idea di provare ad allontanarli sfruttandone la volatilità. In questo lavoro è riportata una tecnica innovativa specificatamente messa a punto dagli autori per rimuovere gli inibitori formatisi nel pretrattamento di steam explosion di biomasse lignocellulosiche. Si è iniziato realizzando un proof of concept (TRL 2-3) con cui è stato dimostrato come fosse possibile detossificare un substrato lignocellulosico sfruttando la volatilità di alcune classi di inibitori. Il metodo è stato validato e perfezionato in laboratorio (TRL 4) e successivamente dimostrato e qualificato in un ambiente rilevante, anche sotto il profilo industriale, utilizzando una apparecchiatura commerciale operante a valle dell’impianto di pretrattamento steam explosion da 150 kg/h STELE installato nel Centro Ricerche ENEA della Trisaia (MT). É stato quindi raggiunto il TRL 8 in linea con quanto auspicato dal progetto PRIT (PRetrattamento Italiano), finanziato e realizzato nell’ambito del programma Industria 2015, nel cui contesto la ricerca è stata condotta. Sono stati ideati e dimostrate con successo 3 modalità operative: 1) Reattore a letto fisso consistente in un tubo di vetro incamiciato (termostatabile) all’interno del quale è confinato il materiale esploso contenente gli inibitori. 2) Reattore a letto fluidizzato consistente in un tubo di vetro simile al precedente ma oscillante. Infatti, contemporaneamente a un flusso di aria calda, il tubo è sottoposto a un’oscillazione verticale realizzata mediante aggancio con biella a un motore elettrico a numero di giri variabile. 3) Essiccatore pilota a letto fluidizzato.
Ideazione e sperimentazione di sistemi innovativi per la detossificazione di biomassa lignocellulosica finalizzata alla conversione in biocarburanti
Zimbardi, F.;Viola, E.;Arcieri, G.;Valerio, V.;
2021-01-01
Abstract
The pretreatment of lignocellulosic biomass for its transformation first into carbohydrates and then from these, through fermentation processes, into biofuels and chemicals, often involves the use of high-temperature techniques. This produces compounds derived from degradation processes which are called "inhibitors" because they hinder the microbial fermentation processes. Generally, inhibitors are low molecular weight molecules, therefore volatile. Inhibitors are commonly removed by washing with water; however water also removes the soluble carbohydrates. In this work, a specific and innovative removal technique of these inhibitors is reported. The substrate is biomass pretreated by steam explosion. We started by creating a proof of concept (TRL 2-3) with which it was demonstrated how it was possible to detoxify a lignocellulosic substrate by exploiting the volatility of some classes of inhibitors. The method was validated and perfected in the laboratory (TRL 4) and subsequently demonstrated and qualified in a relevant environment, also from an industrial point of view, using commercial equipment operating continuously downstream of the 150 kg / h steam explosion pretreatment plant STELE installed in the ENEA Research Center in Trisaia (MT). A TRL 8 was therefore achieved, in line with what was hoped for by the PRIT (PRetrattamento Italiano) project, funded and implemented under the 2015 Industry program and in the context of which the research was conducted. Overall, 3 types of equipment have been designed, realized and tested: 1) Fixed bed reactor consisting of a jacketed glass tube (thermostatable) inside which the exploded material containing the inhibitors is confined. 2) Fluidized bed reactor consisting in a glass tube similar to the previous one but oscillating. In fact, at the same time as a flow of hot air, the tube is subjected to a vertical oscillation achieved by coupling with a connecting rod to an electric motor with a variable number of revolutions. 3) Pilot fluidized bed dryer.File | Dimensione | Formato | |
---|---|---|---|
RT-2021-06-ENEA.pdf
accesso aperto
Descrizione: Documento completo
Tipologia:
Versione Editoriale (PDF)
Licenza:
Creative commons
Dimensione
4.09 MB
Formato
Adobe PDF
|
4.09 MB | Adobe PDF | Visualizza/Apri |
I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.