Story by: Janna Loeppky, M.S. Candidate, Oregon State University 12/10/13
As a part of the Northwest Advanced Renewables Alliance (NARA) project, several students were selected to conduct research related to site selection, that is, to explore potential locations for biomass conversion refineries and depots. These students are part of the Integrated Design Experience (IDX) course offered by Washington State University and the University of Idaho. In a recent presentation, three groups provided their findings for high potential locations and how they came to their conclusions. These student groups included teams focused on a solid depot, liquid depot and an integrated bio-refinery (defined below). Teams worked within a distinct region identified as the Mid Cascade to Pacific (MC2P) supply chain which includes the west coast of Oregon and Washington.
The Solid Depot team is primarily concerned with the first two steps in the NARA supply chain – forest residues preparation and transportation. This team used a series of decision making processes to determine an ideal location for a plant (preferably at an existing sawmill site) that is able to process solid biomass residues. They discussed the challenges of transporting and reducing residuals to a condition in which they are chipped or pelletized at a capable mill with an economically reasonable location. Due to the financial difficulty of constructing several refineries, the group clustered and ordered site locations of potential refineries according to several factors including rail access, biomass availability, protected land (forest density), median labor force age, distance from ports, environmental factors and electricity costs. Eventually an algorithmic score determined ideal counties and general locations for future building sites. Ideal counties included Columbia County and Grays Harbor County in Washington.
The Liquid Depot group described using ranking rubrics as well as a decision matrix to develop an optimal site for liquid processing. The primary goal of this team was to discover an ideal location for a refinery with the ability to produce sugar-rich liquids from wood residuals. In doing so, this team’s focus included the first four steps of the NARA process: forest residues preparation, transportation, pre-treatment and hydrolysis. Asset factors differed slightly in that critical inputs were unemployment, construction, and electrical expense rates. Due to the similarities in processes between pulp mills and treatment needed to generate sugar-rich liquids from wood biomass, currently established pulp mill locations are more desirable. In evaluating these mills, data were organized into categories such as: forest residual, unemployment, construction and demolition, utilities (electricity, natural gas) mill sites (size, type and status), river drainage and transportation (rail, roads and ports). County locations with high potential for serving as a liquid depot include Grays Harbor County, WA, Cowlitz County, WA and the northwest corner of Oregon.
Finally, the Integrated Bio-refinery team reviewed their peocess on determining a proper location encapsulating all aspects of the biomass supply chain conversion processes. This team was concerned with the last four steps in the NARA supply chain: pre-treatment, hydrolysis, fermentation and final biojet products. Despite the difficulty in analyzing site availability and feasibility, mill sites were successfully determined utilizing factors including biomass density, electricity rates, median income, population density, cost of living, aviation facilities, labor force and median age. Using a decision matrix as well as optimal and capital expenditure models, the team was able to determine optimal refinery locations. These site locations are in Grays Harbor County and Cowlitz County, WA.
To watch a video of the IDX teams’ presentations, see http://www.youtube.com/watch?v=8q-usW6AVq0