Kevin L. Kenney

Understanding biomass feedstock variability

If the singular goal of biomass logistics and the design of biomass feedstock supply systems is to reduce the per-ton supply cost of biomass, these systems may very well develop with ultimate unintended consequences of highly variable and reduced quality biomass feedstocks. This paper demonstrates that, due to inherent species variabilities, production conditions and differing harvest, collection and storage practices, this is a very real scenario that biomass producers and suppliers as well as conversion developers should be aware of. Biomass feedstock attributes of ash, carbohydrates, moisture and particle morphology will be discussed. We will also discuss specifications for these attributes, inherent variability of these attributes in biomass feedstocks, and approaches and solutions for reducing variability for improving feedstock quality.

Uniform-Format Solid Feedstock Supply System: A Commodity-Scale Design to Produce an Infrastructure-Compatible Bulk Solid from Lignocellulosic Biomass -- Executive Summary

This report, Uniform-Format Solid Feedstock Supply System: A Commodity-Scale Design to Produce an Infrastructure-Compatible Bulk Solid from Lignocellulosic Biomass, prepared by Idaho National Laboratory (INL), acknowledges the need and provides supportive designs for an evolutionary progression from present day conventional bale-based supply systems to a uniform-format, bulk solid supply system that transitions incrementally as the industry launches and matures. These designs couple to and build from current state of technology and address science and engineering constraints that have been identified by rigorous sensitivity analyses as having the greatest impact on feedstock supply system efficiencies and costs.

Techno-economic analysis of decentralized biomass processing depots

Decentralized biomass processing facilities, known as biomass depots, may be necessary to achieve feedstock cost, quantity, and quality required to grow the future U.S. bioeconomy. In this paper, we assess three distinct depot configurations for technical difference and economic performance. The depot designs were chosen to compare and contrast a suite of capabilities that a depot could perform ranging from conventional pelleting to sophisticated pretreatment technologies. Our economic analyses indicate that depot processing costs are likely to range from ∼US

A Technical Review on Biomass Processing: Densification, Preprocessing, Modeling and Optimization

30 to US

Practical considerations of moisture in baled biomass feedstocks

63 per dry metric tonne (Mg), depending upon the specific technology implemented and the energy consumption for processing equipment such as grinders and dryers. We conclude that the benefits of integrating depots into the overall biomass feedstock supply chain will outweigh depot processing costs and that incorporation of this technology should be aggressively pursued.

Advanced feedstocks for advanced biofuels: transforming biomass to feedstocks

Biomass from plants can serve as an alternative renewable and carbon-neutral raw material for the production of bioenergy. Low densities of 40–60 kg/m3 for lignocellulosic and 200–400 kg/m3 for woody biomass limits their application for energy purposes. Prior to use in energy applications these materials need to be densified. The densified biomass can have bulk densities over 10 times the raw material helping to significantly reduce technical limitations associated with storage, handling and transportation. Pelleting, briquetting, and other extrusion processes are commonly used methods for densification. The aim of the present research is to develop a comprehensive review of biomass processes including densification, preprocessing, modeling and optimization. Specific objectives include performing a technical review on (a) mechanisms of particle bonding during densification; (b) methods of densification including extrusion, briquetting, pelleting, and agglomeration; (c) effects of process and feedstock variables on biomass chemical composition and densification (d) effects of preprocessing (e.g., grinding, preheating, steam explosion, and torrefaction) on biomass quality and binding characteristics; (e) models for understanding compression characteristics; and (f) procedures for response surface modeling and optimization.

Feedstock Supply System Design and Economics for Conversion of Lignocellulosic Biomass to Hydrocarbon Fuels Conversion Pathway: Fast Pyrolysis and Hydrotreating Bio-Oil Pathway "The 2017 Design Case"

Background: The biomass industry requires low-cost, moisture-tolerant storage solutions to preserve herbaceous feedstocks. Methodology: We examined moisture movement in storage and identified patterns of migration, as well as their impacts on moisture measurement and dry matter recovery. Baled corn stover and energy sorghum were stored outdoors in uncovered, tarp-covered or wrapped stacks, and sampled to measure moisture and dry matter losses. Results: Interpolation between sampling locations showed clear patterns of moisture accumulation and redeposition. Exposure, orientation and contact with barriers caused the greatest amount of moisture heterogeneity within stacks. Although the bulk moisture content remained in the range suitable for aerobic stability, regions of high moisture supported microbial activity, resulting in dry matter loss. Conclusion: Stack configuration, orientation and coverage methods improve moisture management and dry matter preservation.

Data driven decision support for reliable biomass feedstock preprocessing

Biomass, with its energy-rich stores of fixed carbon and volatiles, is estimated to have a worldwide bioenergy potential ranging from nearly 10% to more than 60% of primary energy consumption [1]. Various governments have set aggressive bioenergy development goals to offset fossil fuel consumption with biopower and/or biofuel production [2–6]. Whether producing biofuels, biopower or other bioproducts, the viability of cellulosic biomass conversion facilities will depend on feedstock supply systems that ensure low-cost, high-volume and onspec availability of biomass, which is projected by 2050 to require feedstock logistics volumes that are greater than our current energy and agricultural commodities combined [1]. Of the three factors – cost, quality and volume – feedstock cost is currently the major determinant in the viability of commercial-scale bioenergy production. Ideally, conversion facilities would prefer to receive feedstocks that are consistent in quality attributes, such as moisture, ash and convertible sugars, that allow their technologies to operate most efficiently. However, the current reality is that the suitability of biomass as a feedstock is determined by total delivered cost and minimum tolerable quality specifications for a specific conversion technology. This reality allows use of just a small portion of the potential biomass resources identified for bioenergy production [7]. This comparison of reality to an ideal situation, which we often simulate in the research laboratory, can be extended to a comparison of raw biomass with feedstock. Feedstocks are characterized by specifications that imply consistency and reliability. Raw biomass is incredibly diverse in chemical and physical properties, depending on plant physiology, agronomic and environmental conditions, as well as differences in the way biomass is harvested, stored and processed prior to conversion. Much of the biomass logistics research, development and demonstration activities conducted to date have attempted to offset these quality-related issues of raw biomass by driving down logistics costs. This special focus issue is intended to explore an expanded feedstock development approach that actively addresses feedstock quality throughout the entire supply chain to collectively transform raw biomass to high-quality, on-spec feedstocks. This special focus issue highlights a broad selection of practices and technologies that move beyond logistics to reduce variability and improve quality of biomass feedstocks. Overarching issues of quality are presented in a perspective by Kenney et al. on the importance of consistent feedstock quality as major logistic and operational considerations in the design of biomass conversion systems [8]. This paper presents results of extensive characterization of biomass ash, sugar and moisture content, Advanced feedstocks for advanced biofuels: transforming biomass to feedstocks Foreword

Virtual Engineering Approach to Developing Selective Harvest Technologies

The U.S. Department of Energy promotes the production of liquid fuels from lignocellulosic biomass feedstocks by funding fundamental and applied research that advances the state of technology in biomass sustainable supply, logistics, conversion, and overall system sustainability. As part of its involvement in this program, Idaho National Laboratory (INL) investigates the feedstock logistics economics and sustainability of these fuels. Between 2000 and 2012, INL quantified and the economics and sustainability of moving biomass from the field or stand to the throat of the conversion process using conventional equipment and processes. All previous work to 2012 was designed to improve the efficiency and decrease costs under conventional supply systems. The 2012 programmatic target was to demonstrate a biomass logistics cost of

Economically Optimum Production of Both the Agricultural Biomass Feedstock and the Crop

55/dry Ton for woody biomass delivered to fast pyrolysis conversion facility. The goal was achieved by applying field and process demonstration unit-scale data from harvest, collection, storage, preprocessing, handling, and transportation operations into INL’s biomass logistics model.