The conversion of low-grade lignocellulosic biomass such as residual wood or straw to synthetic fuels and chemicals is currently being developed within the bioliq® concept (at the Karlsruhe Institute of Technology – KIT, Germany). The aim of this study is to model and assess three different synthesis process concepts with DME (dimethyl ether) as a platform chemical. The process concepts are designed and assessed using existing technologies, as well as the previous studies for pyrolysis and gasification sections. The respective considered products in the selected concepts are synthetic gasoline, ethylene and propylene. Using biomass for these applications can reduce fossil CO2 emissions by replacing non-renewable carbon sources. The techno-economic assessment concludes that total energy efficiency ranges between 37.5% and 41.1% for the production of gasoline and olefins, respectively. The resulting specific production cost in the gasoline concept is 72% higher than the current market price. In the olefins concept the difference to the current market prices of ethylene and propylene is reduced to 40%. The specific production costs in the gasoline and ethylene concept are 59% higher than current market prices. The possibility to sequestrate CO2 within the considered concepts at costs of 39 €/t allow additional revenues from sequestrated CO2. In order to meet current market prices, the implications of sequestrated CO2, mineral oil tax reduction and the combination of both kinds of subsidies are evaluated in this study.Baden-Württemberg Ministry of Agriculture (MLR)Agency of Renewable Resources (FNR) of the German Ministry of Food, Agriculture and Consumer Protection (BMELV)Ministerio de Educacion FPU Program (AP2010-0119

The use of biomass in the production of plastics can contribute to the depletion of greenhouse gas (GHG) emissions and secondarily to partially fulfill the growing demand for plastics expected in the near future. The aim of this study is to assess the production of ethylene, one of the most important commodities in the petrochemical industry, via the dehydration of bioethanol and the conversion of bio-dimethyl ether (bio-DME) into olefins. Four case studies have been developed taking into account the different origins of bioethanol, and one for the conversion of bio-DME. The assessment includes current and promising processes for the production of bioethanol, i.e., 1st generation and 2nd generation bioethanol. The latter comprises biochemical processing (enzymatic hydrolysis), thermochemical processing (both direct and indirect syntheses from syngas) and hybrid processing (fermentation of syngas) of biomass. The results show that two of the considered case studies (Brazilian ethanol and ethanol via indirect synthesis from syngas) enable the cost-competitive production of ethylene at current market prices. If BECCS (Bioenergy with Carbon Capture and Storage) is taken into account for the case studies, the results would be substantially enhanced and all cases, except for the case of bioethanol from biochemical processing, would be profitable.Ministerio de Economía y Competitividad ENE2012-31598Ministerio de Educación FPU Program (AP2010-0119

Thermochemical biorefinery based on dimethyl ether (DME) as an intermediate is studied. DME is converted into methyl acetate, which can either be hydrogenated to ethanol or sold as a co-product. Considering this option together with a variety of technologies for syngas upgrading, 12 different process concepts are analyzed. The considered products are ethanol, methyl acetate, H2, DME and electricity. The assessment of each alternative includes biomass pretreatment, gasification, syngas clean-up and conditioning, DME synthesis and conversion, product separation, and heat and power integration. A plant size of 500 MWth processing poplar chips is taken as a basis. The resulting energy efficiency to products ranges from 34.9% to 50.2%. The largest internal rate of return (28.74%) corresponds to a concept which produces methyl acetate, DME and electricity (exported to grid). A sensitivity analysis with respect to total plant investment (TPI), total operation costs (TOC) and market price of products was carried out. The overall conclusion is that, despite its greater complexity, this kind of thermochemical biorefinery is more profitable than thermochemical bioprocesses oriented to a single product.Ministerio de Economía y Competitividad CEN-2009104