Integrated SNG Production in a Typical Nordic Sawmill

Abstract

Advanced biomass-based motor fuels and chemicals are becoming increasingly important to replace fossil energy sources within the coming decades. It is likely that the new biorefineries will evolve mainly from existing forest industry sites, as they already have the required biomass handling infrastructure in place. The main objective of this work is to assess the potential for increasing the profit margin from sawmill byproducts by integrating innovative downstream processes. The focus is on the techno-economic evaluation of an integrated site for biomass-based synthetic natural gas (bio-SNG) production. The option of using the syngas in a biomass-integrated gasification combined cycle (b-IGCC) for the production of electricity (instead of SNG) is also considered for comparison. The process flowsheets that are used to analyze the energy and material balances are modelled in MATLAB and Simulink. A mathematical process integration model of a typical Nordic sawmill is used to analyze the effects on the energy flows in the overall site, as well as to evaluate the site economics. Different plant sizes have been considered in order to assess the economy-of-scale effect. The technical data required as input are collected from the literature and, in some cases, from experiments. The investment cost is evaluated on the basis of conducted studies, third party supplier budget quotations and in-house database information. This paper presents complete material and energy balances of the considered processes and the resulting process economics. Results show that in order for the integrated SNG production to be favored, depending on the sawmill size, a biofuel subsidy in the order of 28-52 €/MWh SNG is required.

Large-scale introduction of forest-based biorefineries: actor perspectives and the impacts of a dynamic biomass market

“…Investment cost correlation for each configuration depending on the size of the host sawmill, derived from [2]. X is the annual production of sawn wood in m 3 .…”

“…Producing bio-synthetic natural gas (Bio-SNG) by gasification of forest residues is an economically viable option for manufacturing biofuels with high efficiency [1]. The economic case is enhanced further if Bio-SNG production is feedstock and heat-integrated with a sawmill [2][3][4]. Bio-SNG can be liquefied to produce liquefied biomethane (LBG), which can directly replace liquefied natural gas (LNG) in transport and heavy industry in areas without a gas grid [2].…”

Technoeconomic Assessment of Hybrid Organosolv–Steam Explosion Pretreatment of Woody Biomass

“…Therefore, some form of capacity expansion is inevitable even with integrated design options. In case of integration at a sawmill site, where the feedstock can be sourced onsite, the cost of feedstock reduces due to the avoided cost of transportation and logistics leading to improved economic performance of the biorefinery concepts, e.g., Reference [24].…”

Value chains for integrated production of liquefied bio-SNG at sawmill sites – Techno-economic and carbon footprint evaluation

“…Sweden is used as a case study, but the results are relevant for other countries with significant forest resources and sawmill facilities. Sawmill-integrated bio-SNG production has been investigated previously by Mesfun et al [20], who used a process integration approach to assess the potential for increasing the profit margin of sawmill by-products by using them for production of bio-SNG or production of electricity in an integrated gasification combined cycle. Pettersson et al [6] used a geographically explicit approach to evaluate different forest industry integrated biofuel production options.…”