CHP-Integrated Fischer-Tropsch Biocrude Production under Norwegian Conditions: Techno-Economic Analysis

Abstract

This article presents a detailed techno-economic analysis, under Norwegian conditions, for the production of biocrude from woody biomass via high temperature entrained flow gasification and Fischer−Tropsch (FT) synthesis with integrated coproduction of heat and electricity. Biomass pretreatment based on both conventional drying and torrefaction processes are considered as options. Maximum calculated efficiency of biocrude at lower and upper bound CO conversions of 40% and 80% at the gasifier operating conditions of lambda value 0.2 and temperature 1300°C are 27% and 44%, respectively. Under these conditions, maximum thermal and net electrical efficiency are 55% and 15.5%, respectively. The economic viability of the biocrude production for plant capacities in the range of 150−600 MW thermal input has been evaluated as a function of the type of biomass pretreatment, gasification operating conditions, and the heat to electricity production ratios. Results from the economic analysis show that coproduction of biocrude combined with 100% heat production for district heating gives the lowest biocrude cost under Norwegian conditions, with large variations as the electricity to heat production ratio increases.

Decentralized Production of Fischer–Tropsch Biocrude via Coprocessing of Woody Biomass and Wet Organic Waste in Entrained Flow Gasification: Techno-Economic Analysis

“…Fines, containing particles with size below 1 mm, are collected and introduced directly into the gasifier. Torrefaction of the woody biomass improves the grindability and energy density of the input feedstock to gasification leading to a better economic performance of the overall biocrude production compared to pretreatment based on conventional drying only, as it has been proven already in a previous work by the authors [12]. Pretreatment of the sludge includes drying and grinding.…”

“…However, although co-production of heat theoretically improves the economics of biocrude production, there is a practical limitation in the amount of heat that can be exported to district heating networks, since biocrude production plants would be located close to the forest. On the other hand, when considering the conversion of biomass to biocrude with plant capacities in the range of 150 to 600 MW, the costs of feedstock supply become significant and can represent about 26-38 % of the total operating cost of the plant [12].…”

“…The cost index used in this study is based on the Chemical Engineering Plant Cost Index (CEPCI). Values for are based on individual installation factors per type of process equipment developed by Woods [45] with an updated labor correction factor under Norwegian conditions of 1.47.The purchase cost functions for the main process equipment that has been considered in this work are based on data published by the authors in a previous work[12], with modifications as presented below. The cost of feedstock storage at the plant is calculated from ∑ , , where is the storage time capacity, assumed to be one week, and , is the storage cost per unit volume, which is assumed to be constant and equal to 5.3 €/m 3 not dependent on the type of feedstock.…”

Techno-Economics of Biocarbon Production Processes under Norwegian Conditions

“…The purchase equipment and installation cost were evaluated based on the function defined by Kempegowda et al, , which is a modified version of the Guthrie–Ulrich method and includes pressure, materials, and required auxiliary systems, i.e., electric system, piping and valves, instrumentation and control, through simple multiplication factors.…”

“…These are coupled to purchase equipment installation factors through eq . This is based on the work of Kempegowda et al where (Σ i C S,I,i ) is the total purchase and installation cost in $, for the overall plant, and f i represent additional costs factors including civil work associated with site preparation and process-equipment building, offsite accessibility and services, contingency margin, contractors, land, royalties, and patents. Cost factors that are shown in TPEC are only one part of the total costs associated with plant construction, as shown in Table .…”