Embed Size (px)
Citation preview
Wood Pellet Workshop Vancouver Marriot Pinnacle Hotel
November 17, 2014
1 9:00-‐9:40 Recent advances in wood pellet science and engineering Dr. Shahab Sokhansanj (UBC)
2 9:40-‐10:20 Life cycle analysis for wood pellets Dr. Warren Mabee (Queen’s University)
3 10:20-‐10:30 Break
4 10:30-‐11:15 Pellets to fuel heat and CO2 producWon for greenhouses
Dr. Mark Lefsrud (McGill)
5 11:15-‐ 12:00 InnovaWve wood drying for pellet Dr. Stefan Cenkowski (U. Manitoba)
6 12:00-‐1:30 Lunch trade show WPAC
7 1:30-‐2:15 TorrefacWon (Steam or dry) -‐ Pre or post pelleWzaWon, Bahman Ghiasi (UBC)
8 2:15-‐3:00 Fundamentals of operaWons resaerch applied to feedstock and pellets handling
Dr. Mahmoud Ebadian, Consultant
9 3:00-‐3:15 Break
10 3:15-‐4:00 Gas emissions and dry mass loss from stored woody biomass residues Dr. Anthony Lau (UBC)
11 4:00-‐4:45 Sustainability and emission reducWons
Dr. Terry McIntyre (BFN)/Ms. Olga Petrov
A brief survey of research on wood pellets
Shahab Sokhansanj
Presented at the
Third Wood PelleWzaWon Workshop in conjuncWon with 2014 Wood Pellet AssociaWon of
Canada -‐ AGM November 17, 2014 Vancouver, Canada
17 22
35
51 54
15.7 22.4 25.5
0
10
20
30
40
50
60
2010 2012 2015 2020 2025
Million tonn
es
Demand ProducWon
World Pellet produc9on and demand
Wood Pellet Produc9on –North America
1
2
3
5
6
7
8
9
Million tonnes
Global biomass trade routes
Research topics: • Diversity of feedstock, • logisWcs (handling, storage) • Sustainability
• Understand structural and compositional make up of biomass – concerned with quality, cost, volumes, and environment.
• Develop engineering equations and data for design of unit operations.
• Develop mass and energy balances for TEA and LCA • Develop logistical and integration models • Develop standards and practices for quality evaluations -
safety • Train and mentor highly qualified engineering (HQP) graduates
in clean energy • Attend to short and long term needs of industry
Approach
Pellet mill
Hammer mill Torrefier
UBC Biomass Gasifier
Wood pellet plant
Biomass & Bieoenrgy Research Group
Biomass drying is a highly integrated system The installa9on on the leL of the green drum is the biomass burner. The air and dried biomass are separated in a cyclone. The exit air from cyclone is further cleaned from par9culate maOer in a baghouse.
DRYERGRINDER SIZING
BIOMASS BURNER
EMISSION CONTROL
WET BIOMASS
DRY BIOMASS
HOG FUEL
HEAT RECOVERY
Effect of ini9al moisture content on the cost of drying
0.00
2.00
4.00
6.00
8.00
10.00
12.00
14.00
16.00
18.00
MC=25% MC=50% MC=70%
Fuel cost ($/Mg)
Fig. 10. Cost of hog fuel to provide heat to a dryer with the capacity to produce 10 Mg/h of biomass at 10% moisture content. The horizontal axis shows the initial moisture content of the biomass. Fuel cost is based on $44/Mg for hog fuel.
Varia9on of par9cle size affects drying rates
0.0
0.2
0.4
0.6
0.8
1.0
0 100 200 300 400 500 600
Moisture ra9o
Time (min)
Moisture ra9o vs. 9me (from 50 % MC at 100 °C)
Large
Medium
Small
(Source: University of British Columbia)
Size: Based on thickness Large (10-35 mm), Medium (3-10 mm), Small (3.5 mm). The length of pieces in each group ranged from 10 mm to 50 mm.
Three Industrial Size Reduc9on Equa9ons
n=1.5
n=1.0
n=2.0
Bond
Rifnger
Kick
dE = power input K = constant LF = size of the feed LP = size of the ground product
Ques9ons: Applicability to fibrous biomass? DefiniWon of parWcle size?
[1] and [2]
[1] and [2]
[1] and [2]
[1] Earle and Earle, 1983; [2] Perry et al., 1997;
P
FK L
LKE ln=
nLdLKdE −=
)11( 2/12/1FP
B LLKE −=
)11(FP
R LLKE −=
Size reduc9on
14
Douglas-‐fir Pine Aspen Hybrid poplar
Wheat straw Corn stover
Miscanthus Willow
15
0 50
100 150 200 250
0 1 2 3 4 5 6
Spec
ific
ener
gy, k
J/kg
1/Lp-1/Lf
Rittinger's Law (with intercept) Hybrid willow Douglas-fir Canola Oat Barley straw Wheat straw Switchgrass Corn stover
Specific energy required to reduce the size of biomass particles from Lf to final size Lp. The fit to Rittinger’s equation
⎟⎟
⎠
⎞
⎜⎜
⎝
⎛−=
fpR L
1L1KE
Size reduction
y = 67.312x R² = 0.91384
0 20 40 60 80
100
0 0.5 1 1.5 Spe
cific
ene
rgy,
kJ/
kg
(1/Lp)-(1/Lf)
0 5
10 15 20 25 30 35 40
Ene
rgy
inpu
t (kW
h/t)
3.2 mm
6.4 mm
Refnger equaWon had a good fit to the hammer mill data
Grinding stover past 6 mm screen fracWonates into a hairy material and ground parWcles
Pine
Energy input to make pellets
0
20
40
60
80
Ene
rgy
Inpu
t (M
J/dr
y t)
0
10
20
30
40
Ene
rgy
Inpu
t (M
J/dr
y t) FricWon
y = 133.51e2.0087x R² = 0.8482
0
2,000
4,000
6,000
8,000
0.0 0.5 1.0 1.5 2.0
Forc
e (N
)
Distance ratio (Lr)
Forming pellets in the die
0
40
80
120
160
200
0.0 5.0 10.0 15.0
Forc
e (N
)
Distance (mm)
Expulsion of pellets from die
Compression
PelleWzaWon
17
0
1000
2000
3000
4000
5000
0 10 20 30 40 50
Force, N
Displacement, mm
Douglas-‐fir Hybrid willow Miscanthus
• Miscanthus (an agricultural biomass) used more energy to pelleWze comparing to woody biomass;
• Specific energy of size reducWon is more than specific energy of pelleWzaWon;
Miscanthus Pellets
mm screen 2 4 6
Microscopic surface picture of the 5 mm particle (a&b top) before drying and (c&d bottom) after drying, up to temperature of 150 C.
For drying temperatures lower than 100 ˚C, mass loss decreased from 0.25 to 5 mm particles. After 100 ˚C, 5 mm particle showed different behavior which was described by some observed cracks into the structure of particle.
18
Effect of parWcle size and shape (raw wood and pellet parWcles) on high temperature pyrolysis (0.5 mm to 5 mm parWcles)
Pellet parWcles are denser and more regular in shape than saw dust parWcles
Concluding thougts
• Pelle9zed fuels (biomass) is a new and exci9ng area in the bioenergy industry that is expanding rapidly.
• Rapid growth oLen coincides with modifying or crea9ng new ways to increase output of exis9ng and newly developed process equipment and products to keep up with demand.
• These changes in processing will raise new ques9ons about safety and cost compe99veness that will need to be researched and developed for the industry to succeed.
BBRG conducts science and engineering research on adding value to unused biomass from forestry, agriculture, and MSW – New dedicated Lab (Gas Gun) • Densifica9on (pelle9za9on, briquecng) • Drying, size reduc9on, storage • Logis9cs modeling and process designs • Life cycle analysis • Safety
Short and long term R&D projects
:
A DREAM PLACE
Pellet mill
Size reducWon mill Torrefier & steam treatment
UBC biomass gasificaWon CHP -‐ BRDF
Wood pellet plant
Biomass and Bioenergy Research Group (BBRG) facili9es and resources
Gas Gun Bldg
Single Pellet mill
Pilot scale storage
Organizing Committee and Contacts Program co-chairs: Fahimeh Yazdanpanah ([email protected]) Hamid Rezaei, [email protected] Communications: Jun Sian Lee, [email protected] Executive Committee Members: Maryam Tajilrou, [email protected] Rachel Wang, [email protected] David Zamar, [email protected] Members of the organizing committee except PDF Dr. Yazdanpanah are UBC graduate students
Pellet Science & Engineering an Update
Shahab Sokhansanj
Chemical and Biological Engineering Department The University of British Columbia
Biomass & Bioenergy Research Group
Acknowledgement • NSERC – Regional Opportunity Fund, Discovery Grant, CRD
Strategic Program, • Biofuel Network (Centers of Excellence), BioFuelNet.Ca • Wood Pellet AssociaWon of Canada
– Pinnacle, Premium Pellet, Viridis, Princeton Cogen, Pacific Bio (PG) • BC Ministry of Forest • NRCan -‐ Canmet Energy • CEATI – Electric power producing consorWum -‐ OPG • Cogent Industries • Agriculture & Agri-‐Food Canada • Nexterra • Global Biocoal Inc. • Ontario Ministry of Agriculture, Food and Rural Affairs • Fibreco, Inc. North Vancouver • BC Bioenergy Network
