Upload
dokhuong
View
217
Download
1
Embed Size (px)
Citation preview
The Future of Drop-In Fuels
Arpad Horvath, Corinne Scown, Michael Taptich, Kate Piscopo
University of California, Berkeley
December 19th, 2016
Project Team Arpad Horvath, PI
Professor Department of Civil and Environmental Engineering
University of California, Berkeley
Corinne Scown Research Scientist
Energy Technologies Area Lawrence Berkeley National Laboratory
2
Michael Taptich Graduate Student Researcher
Department of Civil and Environmental Engineering University of California, Berkeley
Kate Piscopo
Graduate Student Researcher Department of Civil and Environmental Engineering
University of California, Berkeley
Project Objectives 1) Review the literature to gather existing information related to
renewable drop-in fuels. » Establish if data are available for life-cycle assessments of various technology
pathways and their related costs and environmental impacts.
2) Analyze technology, feasibility, costs, and environmental impacts at both demonstration and commercial scale.
» Estimate where facilities could potentially be located in order to maximize production while minimizing environmental impacts.
3) Identify additional areas of research to facilitate the growing need for data related to technological advancement, costs, and environmental impacts.
4) Identify barriers to the success of these technologies, and where applicable, strategies to overcome these barriers.
5) Develop a strategy to monitor and track progress of these technologies, as well as supplies and costs.
3
TASK 1: REVIEW OF LITERATURE AND ONGOING LABORATORY RESEARCH
The Future of Drop-In Fuels
Petroleum & Alternative Fuel Use in California
5 2014, Higher Heating Value, Source: EIA 2014
Review: Fuels of Interest
Diesel (size ~ C12-20) » 75% saturated hydrocarbons – paraffins, etc. » 25% aromatic hydrocarbons
Gasoline (size ~ C4-12) » 55% paraffins » 25% aromatic hydrocarbons » 10% each of cycloparaffins & olefins
Jet fuel (Jet A or Jet A-1) (size ~ C8-16) » 80% saturated hydrocarbons – paraffins, etc. » 20% aromatic hydrocarbons
6
General Findings on Drop-in Fuels
Two types of drop-in fuels: » Bio-based crude that can be processed alongside
conventional crude in a petroleum refinery (preferred) » Finished product that is compatible with existing infrastructure
and engines The term “drop-in” is used liberally, even when fuel can
only be blended at limited fraction Just because a process results in hydrocarbons doesn’t
mean it is a 1:1 replacement for a fuel Some fuels may be drop-in if supplemented with the
necessary additives Challenge: new fuels are typically produced at volumes
too small (mL) for required properties and engine testing 7
What is Drop-In Diesel?
Fuel production researchers tend to focus on C number
Important characteristics: » Cetane number » Energy content » Density » Lubricity » Cold-flow properties » Sulfur content » Stability
Need fuel testing to confirm whether fuel is potentially “drop-in”
8 Source: Chevron http://www.chevronwithtechron.ca/products/documents/Diesel_Fuel_Tech_Review.pdf
What is Drop-In Gasoline?
Fuel production researchers focus on C number
Important characteristics: » Octane number » Stability » Energy content » Density » Sulfur content » Vapor pressure
9 Source: Chevron http://www.chevronwithtechron.ca/products/documents/69083_MotorGas_Tech_Review.pdf
Variation in Feedstock Composition
C6 polysaccharides
10
C5 polysaccharides Polyaromatic Polysaccharide-to-lignin ratio generally higher for herbaceous biomass
Importance of Composition
Ratio of polysaccharides to lignin should play into pathway choice for feedstocks
Old industry saying: “You can make anything from lignin except money”
Majority of synthetic vanillin used to be made from lignin (black liquor), but market share has fallen
11
Short-term: Harsh processes convert at least some lignin to useable fuel
Long-term: Targeted breaking of bonds via biological or catalytic routes offers more flexibility, better yields
Dauenhauer video of lignin pyrolysis: https://www.youtube.com/watch?v=E1pq2lg-lkI
Overview of Pathway Types
Biological: Pathways that begin with sugars, sourced from either sugar, starch, or biomass feedstocks, and utilize host microbes to produce final fuels.
Hybrid biological/chemical: Pathways that begin with sugars, sourced from either sugar, starch, or biomass feedstocks, and utilize host microbes to produce fuel precursors that are converted through catalytic processes to final fuel products.
Chemical: Pathways that begin with sugars, sourced from either sugar, starch, or biomass feedstocks, or lipids, and utilize purely chemical routes to producing fuels. Furan pathways that convert five-carbon sugars to furfural, and ultimately to fuels are an example, as are renewable diesel pathways.
Thermochemical: Pathways that use high-temperature processes such as pyrolysis or gasification to produce fuel mixtures.
12
13
or no additives
More options for diesel
Biological pathways are useful jumping-off point
Focus on Thermochemical Pathways
Although yields and blending limits may vary, thermochemical pathways are generally closer to commercialization
Biological and hybrid biological-catalytic routes offer more precision/control and may be a better long-term solution
14
Pathway: Pyrolysis
Fast pyrolysis of biomass to bio-oil » Rapid heating of biomass in the absence of oxygen
to temperatures of 400 - 600°C to thermally decompose the biomass
» Products include light gaseous hydrocarbons, solid char, and a mixture of oxygenated hydrocarbons referred to as pyrolysis oil, or bio-oil.
Hydrotreating the bio-oil to drop-in gasoline and diesel
15
16
Pyrolysis
Data source: PNNL (2013)
Pathway: Gasification/F-T
Relatively mature process, but less so for biomass applications
Gasification of biomass to CO and H2 » Occurs in presence of oxygen and higher
temperatures than pyrolysis: 800°C Water-gas shift reaction used to adjust H2:CO
ratio to optimal point for F-T reaction (2.1:1 ) F-T reaction grows diesel chains:
» CO + 2.1H2 → --(CH2)-- + H2O 17
18
Gasification/Fischer-Tropsch
Pathway: Gasification/MTG
Also relatively mature process, demonstrated at commercial scale in New Zealand, several plants under construction in U.S.
Scrubbed syngas enters steam reforming step, (800 - 900°C), adjusts H2:CO ratio to 2:1
Methanol synthesis reactor Methanol partially dehydrated to dimethyl ether
(DME), then DME converted to olefins, and then aromatics and paraffins
19
Gasification/MTG
20
TASK 3: SCALE-UP SCENARIO METHODS
The Future of Drop-In Fuels
Scale-Up Scenario Objectives & Constraints
22
Components of the California Drop-In (CAdi) Fuel Logistics Model
23
24
Distribution of CA
Biomass
• Forest residues: 44% of CA total biomass
• Forest residues & primary mill wastes concentrated in NCM
• Crop residues in the CV region
• Urban wood & secondary mill wastes in the CCS
• Herbaceous: 26%, Woody biomass: 74% of total
Potential Biorefinery Locations
25
Red: new development for drop-in fuels Black: petroleum refinery Orange: biodiesel refinery Green: ethanol refinery
Bulk Fuel Terminals & Fuel Demand Service Areas
26
• Terminal: storage facility used primarily for petroleum products with total bulk storage capacity >= 50,000 barrels
• In absence of storage capacity data, terminal storage based on county-level retail fuel sales, allocated to tracts based on population, reallocated to terminals based on minimum travel distances by truck.
TASK 2: LIFE-CYCLE COST AND ENVIRONMENTAL ASSESSMENT DATA GAP ANALYSIS
The Future of Drop-In Fuels
Pathway Yields
28 Values rounded to two significant figures, MT = metric ton, GGE = gallon of gasoline equivalent
Energy Demand by Pathway
29
Values rounded to 2 significant digits, GGE = gallon of gasoline equivalent, NG = natural gas, off-gases = noncondensable light hydrocarbons emitted from unit processes
Nth Plant Assumptions
30 *MACRS = Modified Accelerated Cost Recovery System
Cost Assessment Summary
31
Based on 2000 metric tons/day plant size Notable inconsistencies in literature:
» Construction period: Pyrolysis and the FT pathways assumed a 3-year construction period. MTG assumes a 2.5-year construction period.
» Plant life: MTG and FT assume a 20-year plant life while the pyrolysis pathway costs were calculated assuming a 30-year plant life
All based on Aspen modeling, so cannot verify these assumption until more commercial-scale facilities are built and operated
Values rounded to two significant digits. GGE = gallon of gasoline equivalent. All values are in 2014 dollars.
GHG Emission Factors
32
GHG Emissions Comparison
33
Yield & Emissions by Pathway
34
Not including electricity credits FT and MTG Pathways have 0 GHG emissions due to steam cycles and combustion of biogenic carbon. Error bars represent the range in yields found in the literature. GGE = Gallon of gasoline equivalent, MT = metric ton
GHG Emissions Using System Expansion
35
Negative values for FT and MTG pathways are due to offset credits for net electricity exports, using system expansion. Base case assumes system expansion to CAMX grid, lower bound of error bars assumes system expansion to WECC grid, and upper bound assumes system expansion to offset straight natural gas.
CAP Results:
Pyrolysis
36
CAP Results: Fischer-Tropsch
37
CAP Results:
MTG
38
Pathway CAP Results
39
Error bars represent different energy offset for system expansion allocation, in addition to variations in yield and emission factors: lower bound = WECC, upper bound = natural gas, baseline value = CAMX
Pathway Water Results
40
TASK 3 RESULTS The Future of Drop-In Fuels
Scenario 1A: Scale-Up Scenario Modeling Results
42
Scenario 1B: Maximize Diesel
43
Scenario 2: Maximize Fuel Output
44
Scenario 3: Incentivize Only New Growth
45
Scenario 4: Incentivize Only Co-Location
46
Scenario 5: Incentivize Distributed Growth
47
Scenario 6: Require Equal Blending
48
Annual Metric ton-km by Supply-Chain Segment and Transport Mode
49
Changes in Emissions from 2015 Baseline
50
Well-to-Pump Emissions
51
Well-to-Pump Emission Factors
52
TASKS 4 & 5: IDENTIFICATION OF RESEARCH NEEDS AND IDENTIFICATION OF POTENTIAL BARRIERS
The Future of Drop-In Fuels
Key Issues
Fuel yield & hydrogen requirements Sugar utilization Clean sugar stream requirements Co-products Biocrude Compatibility with Petroleum Refineries Engine and System Compatibility Well-to-Wheel Criteria Air Pollutant Emissions Potential Production Scale
54
TASK 6: DEVELOPING A STRATEGY TO MONITOR AND TRACK PROGRESS WITH DROP-IN FUELS
The Future of Drop-In Fuels
Sharing Data and Insights
We have documented our scenarios analyses, including three thermochemical pathways, in a wiki, freely available through github, where anyone can access the model and alter parameters to generate new results. This platform provides an opportunity for feedback and suggested changes.
As these pathways develop, yields, emission factors, and other inputs can be changed to generate up-to-date results. The URL is: https://github.com/mtaptich/California-Drop-In-CAdi-Fuel-Model/tree/master/docs
56
Contact Information: Arpad Horvath
Professor Department of Civil and Environmental Engineering
University of California, Berkeley [email protected]
Tel.: 510-642-7300
Corinne Scown Research Scientist
Energy Technologies Area Lawrence Berkeley National Laboratory/Joint BioEnergy Institute
[email protected] Tel.: 510-486-4507
57
Questions?
58
Backup Slides
59
California Feedstock Availability
60
Region North Coast & Mountain Central Valley Central Coast & Southern Label cropres = crop residue forestres = forest residue primmill = primary mill waste secmill = secondary mill waste
Data sources: CBC 2015, NREL 2014
Municipal Solid Waste Makeup
61
Backup: Model Assumptions
62
• Drop-in fuels are perfect substitutes for conventional gasoline, diesel, and marine fuels. (e.g., there is no “blend wall.”)
• Drop-in fuels displace only fuels sold for use in California. • Demand for fuel is fixed, estimated at an annual level, and proportional to population density. • Intermodal terminal exchanges and fuel storage activities have negligible impacts on optimizing transport and
shipment of fuels. • The locations of bulk fuel terminals (total bulk storage capacity of 50,000 barrels or more) are fixed and no additional
pipelines are constructed to move drop-in fuel around the state. Therefore, isolated biorefineries would need trucks and/or trains to move fuel to regional bulk terminals or send their fuels to refineries to ship to terminals via pipelines. The directionality of pipelines is not considered.
• Information regarding the local connections between petroleum product pipelines and bulk terminals is limited in availability. We assume that pipeline-terminal transfers are carried out using 8” pipelines and are situated such that the transport distances are minimized.
• Biorefinery capacity can be designed across a continuum, such that the optimization could be solved as the relaxation of a mixed integer facility location problem.
• Emissions from feedstock collection, transport, and fuel production scale linearly with biomass quantities. • As a means of reducing the dimensionality of our optimization model, which is discussed in a later section, we
combine the mill and urban wood wastes into a single category deemed scrapwood. • Facilities are assumed to support more than one biomass-to-biofuel pathway (e.g., by building two different
biorefineries next to each other in close proximity). • Emissions associated with storage are ignored (e.g., initial biomass handling, evaporative emissions from refined
products, etc.).
Backup: Model
Variables
63
Emission Factors for Biomass Handling
64
• Corn stover used as proxy for all crop residues. • Wood wastes: biomass is ground into course material using a
hammermill grinder, which requires a direct electricity input of 77 kWh per dry ton
Well-to-Wheel Emission Factors for Freight Modes
65
• Heavy-duty truck EFs based on CA In-State Class-8 truck (model year: 2012) using California Air Resources Board’s EMission FACtors (EMFAC) model
• 20.5 MJ/km operational fuel used to calculate the well-to-pump emissions associated with this mode using CA-GREET
• Average of 24.1 metric tons of payload, 50% of the kilometers driven are empty.
• Locomotives achieve the fleet-average fuel economy of 1,132 gross metric ton-km per gallon, hauls an average of 3,500 metric tons/train
Pipeline Emission Factors
66
• Assumed the average pipeline diameter across the distribution network was 8”
• Energy demand: 71 kJ/tkm (electricity) • GIS data for the petroleum product pipeline network data from the
U.S. Energy Information Administration used to determine distances traveled
67
CAP Assumptions
Mode-Shares by Segment
68