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Energy-Efficient Routes for the Production of Gasolinefrom Biogas and Pyrolysis Oil — Process Design and Life-CycleAssessment

View Article: PubMed Central - PubMed

ABSTRACT

Twonovel routes for the production of gasoline from pyrolysisoil (from timber pine) and biogas (from ley grass) are simulated,followed by a cradle-to-gate life-cycle assessment of the two productionroutes. The main aim of this work is to conduct a holistic evaluationof the proposed routes and benchmark them against the conventionalroute of producing gasoline from natural gas. A previously commercializedmethod of synthesizing gasoline involves conversion of natural gasto syngas, which is further converted to methanol, and then as a laststep, the methanol is converted to gasoline. In the new proposed routes,the syngas production step is different; syngas is produced from amixture of pyrolysis oil and biogas in the following two ways: (i)autothermal reforming of pyrolysis oil and biogas, in which thereare two reactions in one reactor (ATR) and (ii) steam reforming ofpyrolysis oil and catalytic partial oxidation of biogas, in whichthere are separated but thermally coupled reactions and reactors (CR).The other two steps to produce methanol from syngas, and gasolinefrom methanol, remain the same. The purpose of this simulation isto have an ex-ante comparison of the performance of the new routesagainst a reference, in terms of energy and sustainability. Thus,at this stage of simulations, nonrigorous, equilibrium-based modelshave been used for reactors, which will give the best case conversionsfor each step. For the conventional production route, conversion andyield data available in the literature have been used, wherever available.Theresults of the process design showed that the second method (separate,but thermally coupled reforming) has a carbon efficiency of 0.53,compared to the conventional route (0.48), as well as the first route(0.40). The life-cycle assessment results revealed that the newlyproposed processes have a clear advantage over the conventional processin some categories, particularly the global warming potential andprimary energy demand; but there are also some in which the conventionalroute fares better, such as the human toxicity potential and the categoriesrelated to land-use change such as biotic production potential andthe groundwater resistance indicator. The results confirmed that eventhough using biomass such as timber pine as raw material does resultin reduced greenhouse gas emissions, the activities associated withbiomass, such as cultivation and harvesting, contribute to the environmentalfootprint, particularly the land use change categories. This givesan impetus to investigate the potential of agricultural, forest, oreven food waste, which would be likely to have a substantially lowerimpact on the environment. Moreover, it could be seen that the sourceof electricity used in the process has a major impact on the environmentalperformance.

No MeSH data available.


Related in: MedlinePlus

A comparisonof biotic production indicator (occupation and transformation)for the three cases.
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fig10: A comparisonof biotic production indicator (occupation and transformation)for the three cases.

Mentions: The biotic production indicator for occupation (the graphon theleft in Figure 10)gives the reduction in biotic production potential of the occupiedland for each activity, over the occupation period (per kilogram ofgasoline produced). In other words, this is the biomass not producedduring that particular activity.69 It canbe seen that the ATR and CR cases have a more negative effect thanthe Base case. The major contributor in the ATR case is the “cultivationand harvesting of timber pine”, while for the CR case it isthe ‘energy for harvesting of ley grass’, which essentiallyinvolves the use of diesel. Harvesting the fully grown timber resultsin the land being cleared of biomass, which takes time to regrow toits earlier potential. Thus, overall, during the use of the land,the biotic potential is reduced. Diesel is produced from crude oil,which involves large refinery complexes. These refinery complexesalso consume power in large quantities, which is supplied by powerplants, which again occupy extensive amounts of land. Thus, all thesesteps contribute to the negative impact on biotic potential for diesel.


Energy-Efficient Routes for the Production of Gasolinefrom Biogas and Pyrolysis Oil — Process Design and Life-CycleAssessment
A comparisonof biotic production indicator (occupation and transformation)for the three cases.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC5384482&req=5

fig10: A comparisonof biotic production indicator (occupation and transformation)for the three cases.
Mentions: The biotic production indicator for occupation (the graphon theleft in Figure 10)gives the reduction in biotic production potential of the occupiedland for each activity, over the occupation period (per kilogram ofgasoline produced). In other words, this is the biomass not producedduring that particular activity.69 It canbe seen that the ATR and CR cases have a more negative effect thanthe Base case. The major contributor in the ATR case is the “cultivationand harvesting of timber pine”, while for the CR case it isthe ‘energy for harvesting of ley grass’, which essentiallyinvolves the use of diesel. Harvesting the fully grown timber resultsin the land being cleared of biomass, which takes time to regrow toits earlier potential. Thus, overall, during the use of the land,the biotic potential is reduced. Diesel is produced from crude oil,which involves large refinery complexes. These refinery complexesalso consume power in large quantities, which is supplied by powerplants, which again occupy extensive amounts of land. Thus, all thesesteps contribute to the negative impact on biotic potential for diesel.

View Article: PubMed Central - PubMed

ABSTRACT

Twonovel routes for the production of gasoline from pyrolysisoil (from timber pine) and biogas (from ley grass) are simulated,followed by a cradle-to-gate life-cycle assessment of the two productionroutes. The main aim of this work is to conduct a holistic evaluationof the proposed routes and benchmark them against the conventionalroute of producing gasoline from natural gas. A previously commercializedmethod of synthesizing gasoline involves conversion of natural gasto syngas, which is further converted to methanol, and then as a laststep, the methanol is converted to gasoline. In the new proposed routes,the syngas production step is different; syngas is produced from amixture of pyrolysis oil and biogas in the following two ways: (i)autothermal reforming of pyrolysis oil and biogas, in which thereare two reactions in one reactor (ATR) and (ii) steam reforming ofpyrolysis oil and catalytic partial oxidation of biogas, in whichthere are separated but thermally coupled reactions and reactors (CR).The other two steps to produce methanol from syngas, and gasolinefrom methanol, remain the same. The purpose of this simulation isto have an ex-ante comparison of the performance of the new routesagainst a reference, in terms of energy and sustainability. Thus,at this stage of simulations, nonrigorous, equilibrium-based modelshave been used for reactors, which will give the best case conversionsfor each step. For the conventional production route, conversion andyield data available in the literature have been used, wherever available.Theresults of the process design showed that the second method (separate,but thermally coupled reforming) has a carbon efficiency of 0.53,compared to the conventional route (0.48), as well as the first route(0.40). The life-cycle assessment results revealed that the newlyproposed processes have a clear advantage over the conventional processin some categories, particularly the global warming potential andprimary energy demand; but there are also some in which the conventionalroute fares better, such as the human toxicity potential and the categoriesrelated to land-use change such as biotic production potential andthe groundwater resistance indicator. The results confirmed that eventhough using biomass such as timber pine as raw material does resultin reduced greenhouse gas emissions, the activities associated withbiomass, such as cultivation and harvesting, contribute to the environmentalfootprint, particularly the land use change categories. This givesan impetus to investigate the potential of agricultural, forest, oreven food waste, which would be likely to have a substantially lowerimpact on the environment. Moreover, it could be seen that the sourceof electricity used in the process has a major impact on the environmentalperformance.

No MeSH data available.


Related in: MedlinePlus