Life-cycle analysis of briquetting post-harvest wood residues Public Workshop, Sacramento, CA May 17, 2017

Transcription

1 Life-cycle analysis of briquetting post-harvest wood residues Public Workshop, Sacramento, CA May 17, 2017 Sevda Alanya-Rosenbaum and Richard Bergman Forest Service, Forest Products Laboratory

2 Goals of Conducting Life Cycle Assessment (LCA) Is it environmentally sustainable? Objective: to quantify environmental impacts associated with briquette production from post-harvest forest residues using life cycle assessment (LCA) tool to better understand its environmental performance across all life-cycle stages explore options on cradle-to-grave activities to improve environmental viability

3 Life Cycle Assessment (LCA) LCA is defined in ISO (1997) as: Compilation and evaluation of the inputs, outputs and the potential environmental impacts of a product system throughout its life cycle" Environmental management tool: to evaluate the environmental impact of goods or services identifying and quantifying energy and materials used, emissions and wastes released to the environment assess overall impact on the environment promote continuous environmental improvement

4 Life Cycle Assessment (LCA) Method International Organization for Standardization (ISO) and standards (ISO, 2006a; 2006b) LCA analyses were modeled using SimaPro 8.2 software The scope of the study is a cradle-to-grave life cycle assessment: from extraction of the raw material through product production to end of life Functional unit is 1 MJ of useful thermal heat output for domestic heating Environmental impact assessment: TRACI impact assessment method

5 Life Cycle Assessment (LCA) Method Data Sources: Operational runs were performed at Big Lagoon, California by Schatz Energy Research Center (SERC) Operational data were collected from the briquetter Briquetter model: RUF Briquetting Systems, RUF 200 Throughput: 200 kg/hr

6 Life Cycle Assessment (LCA) Method Background data such as supply of electricity and propane, etc. from U.S. LCI database and peer-reviewed literature Alternative Scenarios: Remote power generation using wood gasification, diesel and grid electricity Pile & burn credit

7 Cradle-to-grave System Boundary Feedstock Procurement Feedstock Preparation Densification Logistics Use Phase Air dry (in forest) Loading Hauling Chipping Screening Drying (forced) Briquetter Transportation Packaging Distribution Combustion BIOCONVERSION SITE 1 MJ Heat Forest Residues Chipping Briquetting Gate-to-gate system boundary Screening Drying

8 g CO 2 eq. per MJ of Heat Global Warming Impact GHG-emissions reduction potential of 92% 0.12 MJ of fossil fuel consumed to generate 1 MJ of heat from briquette Global Warming Feedstock procurement 2.6% Chipping 7.1% Screening 3.2% 60 Briquetting 0.8% 40 Transportation 15.8% Propane Briquette with gasifier power Drying 69.5% Use phase 1.0% Use phase Briquetting Feedstock procurement Logistics Feedstock preparation Refinery

9 g CO 2 Eq. per MJ of Heat Process Contribution to Global Warming Impact Global Warming Gasifier power has GHG-emissions reduction potential of 13%-28% Pile & burn credits account for 25% reduction in global warming impact Briquette with gasifier power Briquette with diesel power Briquette with grid electricity 50% Pile and burn credit Higher dryer efficiency Feedstock procurement Feedstock preparation Briquetting Logistics Use phase Pile & burn credit

10 % Process contribution Process Contribution to Environmental Impact 100% 80% 60% 40% 20% 0% -20% -40% 50% Pile and burn credit resulted in reduction of environmental impacts range between 20% and 86% -60% -80% -100% Ozone depletion Smog Acidification Eutrophication Human toxicity Ecotoxicity Feedstock procurement Feedstock preparation Briquetting Logistics Use phase Pile & burn credit

11 Concluding Remarks Use of briquettes to substitute for propane for domestic heating reduces GHG emissions by 92%. Using wood gasifier instead of diesel for remote power generation decrease Global Warming impact by 28%. Avoiding pile & burn by utilization of forest residues notably lowers resulting environmental impact.

12 Acknowledgements This material is based upon work supported by a grant from the U.S. Department of Energy under the Biomass Research and Development Initiative program: Award Number DE-EE Forest Operations data: Han-Sup Han, Joel Bisson Anil Raj Kizha Pile and burn data: Indroneil Ganguly, Francesca Pierobon Bioconversion and Gasifier data: Arne Jacobson, Charles Chamberlin, David Carter Kyle Palmer, Anthony Eggink, Mark Severy

13 Thank You Questions? CONTACT Sevda Alanya-Rosenbaum, Ph.D. USDA Forest Service, Forest Products Laboratory Madison, WI