Thermochemical Biorefineries and based on DME as platform chemica = Biorrefinerías termoquímicas basadas en DME como intermediarioconceptual design and technoeconomic assessment = diseño conceptual y análisis tecno-económico

Zusammenfassung

This thesis deals with the conceptual design and assessment of thermochemical biorefineries (through gasification and mostly using DME as a platform chemical), combining the technical, economic, environmental and social (regulation) perspectives. Current projects of thermochemical biorefineries (BTL/G: biomass-to-liquid/gas process) are usually energy-driven and focused on the production of a single biofuel. In this thesis, a different concept is proposed: thermochemical biorefineries using a platform chemical, which is a new field of research focused on the co-production of fuels, chemicals, materials and services (heat and electricity) using lignocellulosic biomass. This kind of biorefinery benefits from potentially better energy and material integration, they are not limited to a single market (energy or chemical) and can produce high-value low-volume product (high-value chemicals) in large-scale facilities. Paper 1 reviews the most important routes (for the design of thermochemical biorefineries) via a platform chemical including those known from petro and carbochemistry, and those recently developed. Paper 2 assesses the use of DME as platform chemical for the synthesis of ethanol from lignocellulosic biomass. This indirect synthesis of ethanol from syngas using the DME hydrocarbonylation route overcomes the limitations of the production of ethanol via direct synthesis (low yield process), enhancing the global energy efficiency of biomass conversion and at milder operating conditions (pressure). Paper 3 assesses the valorization of bioethanol for the production of ethylene as a precursor of plastics and commodities for the organic industry, which could not be produced so efficiently directly from syngas. Despite the conversion of ethanol (platform chemical) into ethylene being a mature technology, the use of bioethanol presents different uncertainties (origin of the bioethanol: 1st, 2nd generation, scale capacity and profitability) which are analyzed in this paper. Paper 4 gives a general view of thermochemical biorefineries and a discussion of the main aspects of the design of thermochemical biorefineries with multiproduction using a platform chemical. The technical, economic, environmental and social (regulation) perspectives are discussed along with recommendations for the future development of thermochemical biorefineries. Paper 5 assesses the design of a thermochemical biorefinery focused on multiproduction using DME as a platform chemical. The selected chemical routes are the carbonylation and hydrocarbonylation of DME. The co-production of a high-value low-volume product (e.g. methyl acetate) and a low-value high volume product (e.g. DME) achieves greatest profitability. Paper 6 assesses the realization of a thermochemical biorefinery producing synthetic gasoline and ethylene through the combination (integration) of two direct routes from syngas producing synthetic gasoline and olefins from DME as a platform chemical. Paper 7 gives a methodology for the assessment of sustainability based on European regulations, using the designs of Paper 5. The resulting savings of GHG emissions are greater than that required by European regulations and, therefore, two alternatives for the valorization of extra-avoided GHG emissions (extra saving) have been proposed: via the sale of CO2 credits (extra-avoided emissions) and the co-feeding of fossil fuels.