Potential for Biomass Utilization in Canada - American Chemical Society

12 Potential for Biomass Utilization in Canada

Downloaded by MONASH UNIV on November 22, 2015 | http://pubs.acs.org Publication Date: January 26, 1979 | doi: 10.1021/bk-1979-0090.ch012

RALPH OVEREND Renewable Energy Resources Branch, Energy, Mines and Resources, Canada

With the realisation that fossil fuels - crude oil, natural gas, tar sands and coals-are of finite extent, the use of renewable resources is advocated in many countries as a means of maintaining energy supplies in the light of declining o i l reserves. Figure 1 shows the decline in crude o i l production in Canada as well as the anticipated production of syncrudes from oil-sands over the next decades. Because of the decline of conventional production of o i l , the transition to "non-conventional" sources of fuel has commenced and will accelerate as the next century approaches. Canada has announced its intention to exploit renewable resources; solar space and water heating and forest fuels are the subject of a recent government program intended to increase the proportion of energy derived from renewable sources from the present 3 1/2% to around10%in the year 2000. In order to achieve this rapid growth i t will be necessary to develop suitable technologies so that renewable energy will be able to contribute to what is essentially a world fueled by liquid and gaseous hydrocarbons. In the case of solar thermal applications, the key will be substitution of solar heat in applications and processes presently served by fossil fuels. For biomass, the key to large scale utilisation will be the conversion of photosynthetically produced material to forms and products compatible with the delivery and end use systems of the petroleum era. It is therefore necessary to analyse those resources and technologies available so as to identify those areas where there is a shortfall in the systems and technologies, before advocating any specific R&D strategy. What is required is a form of resource and technology assessment. This could be summarized in a matrix in which the potential of each resource and technology can be quantified and charted. This matrix is shown in figure 2; the items in each column are illustrative and the lists are by no means exhaustive. The identification of R&D requirements then requires a techno-economic assessment of the possibility of different pathways through the matrix, and is the product of (Resource)* (Transport)* (Conversion Technology)* (Transport)* (End Use). This chapter not subject to U.S. Copyright. Published 1979 American Chemical Society. In Chemistry for Energy; Tomlinson, M., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1979.

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3000


2500

5oo ipssi

1970 Èââ

75

80 YEARS

85

1990

Conservation Potential

Pembina

Accelerated Oil Sands and Heavy Oils Established Reserves and Committed Oil Sands Department of Energy, Mines and Resources, Canada

Figure

1.

Canadian

oil demand

and availability,

high price

scenario

1970-1990

(3)

In Chemistry for Energy; Tomlinson, M., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1979.


FRESH WATER

MARICULTURE

1- Estuaries 2- Open Ocean

SALT WATER

4-

ENERGY PLANTATION

3- A G R O - F O R E S T R Y

2.

4

Biomass technology

RAIL

ROAD

TANKER

PIPELINE

chart

ELECTRICITY

STEAM

TRANSPORT

and resource assessment

C2H5OH

eg: C H

FERMENTATION

SNG

eg: Oil

HYDROGENATION

Oil

eg: Char

ENERGY CROPS

Synthesis Gas

eg: Low BTU Gas

GASIFICATION

Electricity

eg: Steam

COMBUSTION

CONVERSION TECHNOLOGY

PYROLYSIS

Figure

PIPELINE

BARGE

RAIL

ROAD

HARVEST & TRANSPORT

ANIMAL RESIDUE

FIELD RESIDUE

2- A G R I C U L T U R E

PRIMARY HARVEST

FOREST RESIDUE

MILL RESIDUE

1- F O R E S T

RESOURCE


HEAT

eg: Methanol

FUELS

CHEMICAL SYNTHESIS TRANSPORTATION

ELECTRICITY

PROCESS

END U S E


168

CHEMISTRY

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The pathways identified will not a l l satisfy the con straints that Canada's resources and needs identify, particu larly i n view of Canada's endowment o f h y d r a u l i c resources, nuclear potential, gas and coal reserves as well as nonconventional o i l resources such as o i l sands and heavy oils. These r e s o u r c e s are not only c o n s t r a i n t s i n the m a t e r i a l and economic sense but also i n i n s t i t u t i o n a l ways. Examples of such are: n a t u r a l gas i s a C a n a d i a n r e s o u r c e expected to be available well i n t o the 21st C e n t u r y ; h y d r a u l i c and nuclear energy define a baseline in electricity costs of around 30 m i l l / k W h o r $9/GJ (1977 I); methanol f u e l f o r d i r e c t use in automobiles w i l l require replacement of a large quantity of the downstream c a p i t a l stock of the e x i s t i n g petroleum d i s t r i b u t i o n system. Again t h i s i s not an e x h a u s t i v e l i s t , but i t s e r v e s to emphasise that other c r i t e r i a than the t e c h n i c a l f a c t of being a b l e to t r a n s f o r m biomass i n t o any g i v e n p r o d u c t w i l l probably determine the eventual u t i l i s a t i o n of t h i s renewable resource. T o i l l u s t r a t e some o f t h e R&D o p p o r t u n i t i e s i n B i o m a s s , I will d i s c u s s o u r p r e s e n t s t a t e o f k n o w l e d g e o f some o f t h e i t e m s i n the columns of the m a t r i x i n F i g u r e 2. Resources Forestry. The t o t a l b i o m a s s p r o d u c t i v i t y o f C a n a d a i s not known w i t h c e r t a i n t y . Using data from Russian work f o r the northern hemisphere (1), the t o t a l energy content of a l l the c a r b o n f i x e d i n Canada" b y p h o t o s y n t h e s i s i n o n e y e a r i s a r o u n d 100 Ε J (1 E J = 1 0 Joule = 0.948 Quad). This figure is an e x t r e m e l y s m a l l f r a c t i o n o f the s o l a r energy t h a t f a l l s on the Canadian l a n d mass i n a year. The mean s o l a r intensity of 110W/m on C a n a d a ' s 9.96 million s q u a r e km c o r r e s p o n d s t o an annual input of 34 0 0 0 EJ. While biomass offers the most immediate o p p o r t u n i t y i n s o l a r renewable energy, u l t i m a t e l y i t i s t h e c o l l e c t i o n and t r a n s f o r m a t i o n o f s o l a r e n e r g y i n a more d i r e c t f a s h i o n that w i l l p r o v i d e the m a j o r i t y of the renewable energy supply i n the d i s t a n t f u t u r e . At present, however, the less than 0.5$ biological efficiency of transformation of s o l a r - e n e r g y i s compensated f o r by t h e i n h e r e n t s t o r a g e charac teristics and h i g h thermodynamic a v a i l a b i l i t y of the biomass resource. Renewable energy i n the f o r m o f h y d r a u l i c impoundment and biomass c o n t r i b u t e 0 . 8 E J (2) and 0.35 E J (3) respectively t o t h e C a n a d i a n p r i m a r y e n e r g y s u p p l y ( t o t a l l i n g "8.4 Ε J i n 197*0 and w h i l e t h i s c a n be i n c r e a s e d u s i n g k n o w n t e c h n o l o g y , t h e u s e o f s o l a r and a e o l i a n energy s t i l l r e q u i r e s c o n s i d e r a b l e advances i n s t o r a g e t e c h n o l o g y t o be e c o n o m i c a l l y c o m p e t i t i v e . 1 8

2

T e r r e s t r i a l biomass i s o f course dependent on a non renew a b l e resource - the s o i l - f o r mechanical support and the s u p p l y and t r a n s p o r t o f n u t r i e n t s t o t h e g r o w i n g p l a n t . The C a n a d i a n t o t a l l a n d a r e a o f 9 9 6 , 6 9 9 , 0 0 0 ha has the f o l l o w i n g l a n d c l a s sification (4).


12.

Biomass

OVEREND

Utilization

in

Table Land Type

I Area/10 ha

% of

6

Water W i l d l i f e (tundra, Agricultural Urban and Other Forest


169

Canada

muskeg,

81.006 519.105 67.344 6.199 323.045 996.699

etc)

Total

8.1 52.1 6.8 0.6 32.4 10CK0

The m o s t e x t e n s i v e land resource i s the forest, covering 1/3 o f t h e l a n d m a s s . This i s the foundation of the large forest industry i n Canada: an industry employing 1 million people, 300 000 d i r e c t l y a n d 700 000 i n d i r e c t l y , a n d p r o v i d i n g almost 20Î of the value of the export trade. Data from FA0 (5) s o u r c e s show t h e s t a t i s t i c s o f t h e m a j o r f o r e s t c o u n t r i e s marked in order of t h e i r forest inventories. (6) Table Country

Population

Forest

People

106m3

1θ3 Brazil USSR USA Canada India China

109 730 2 5 5 038 213 22

925 801

613 838

217 803

74 73 18 17 10 6

315 250 261 811 180 000

II

Inventory Capita 677.2 287.2 85.4 781.1 16.6 7.2

Round Wood 103m3

Production Capita

163 995 387 600 295 802 121 2 0 6 127 195

465 131

1.49 1.52 1.38 5.32 0.21 0.23

The f o r e s t o p p o r t u n i t y i n C a n a d a f o r e n e r g y p u r p o s e s i n c o n j u n c t i o n w i t h t h e present i n d u s t r y i s almost unmatched elsewhere i n the world. T h u s , a l t h o u g h a p p r o x i m a t e l y h a l f o f t h e wood h a r v e s t e d i n the w o r l d i s f o r f u e l , i t c a n be seen t h a t o n l y a few c o u n t r i e s have sufficient forest resources on a per capita basis to s a t i s f y a large p r o p o r t i o n o f t h e i r energy requirements. The energy demand i n developed countries is presently around 10kW/capita w h i l e i n the " T h i r d w o r l d " i t i s around 500W/capita (7). U s i n g a c o n v e r s i o n o f 1m3 w o o d / a n n u m = 232W ( b a s e d o n t h e h i g h e r h e a t i n g v a l u e o f wood) i t i s e a s y t o s e e why t h e r e is a developing firewood c r i s i s (8). Indeed, a l l the countries i n t h e t a b l e a b o v e w o u l d n o t be a b l e t o meet a l l o f t h e i r n e e d s from forest biomass. The forest energy potential o f Canada has been surveyed (9). The a v a i l a b l e m a t e r i a l is essentially of 3 types. The lowest cost material i s wood r e s i d u e a t t h e e x i s t i n g forest industry processing sites. While about half of the mill



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r e s i d u e ( b a r k , s h a v i n g s and s a w d u s t ) i s a l r e a d y u t i l i s e d f o r energy, i t i s e s t i m a t e d t h a t about 0.l4EJ/annum c o u l d be f u r t h e r u t i l i s e d i n t h e r m a l c o n v e r s i o n t o steam and e l e c t r i c i t y i n t h e f o r e s t i n d u s t r i e s t h a t t o d a y u s e a b o u t 7.5$ o f a l l f u e l o i l and g a s i n s u c h a p p l i c a t i o n s . The e n e r g y f l o w i n t h e f o r e s t i n d u s t r y i s summarised i n f i g u r e 3· Figure 4 i s a g e n e r a l i s e d diagram o f the d i s t r i b u t i o n o f b i o m a s s among t r e e components. Today o n l y t h e b o l e o f t h e t r e e i s h a r v e s t e d f r o m t h e f o r e s t ; t h e t o p s , l i m b s and r o o t s a r e l e f t behind. W i t h s i g n i f i c a n t changes i n h a r v e s t i n g t e c h n o l o g y some o f w h i c h a r e a l r e a d y i n p r o c e s s - i t w i l l be p o s s i b l e t o c o l l e c t and u t i l i s e f o r e s t r e s i d u e . F o r Canadian s p e c i e s , ex r o o t , i t i s e s t i m a t e d t h a t an i n c r e a s e o f a b o u t 0.6 ΕJ o v e r t h e p r e s e n t 1.0 E J e n e r g y e q u i v a l e n t o f r o u n d wood h a r v e s t e d c o u l d be o b t a i n e d . W h i l e the h a r v e s t i n g o f t r e e s f o r energy alone i s l i k e l y t o be t o o e x p e n s i v e , t h e u n u t i l i s e d f o r e s t o f Canada c o u l d t h e o r e t i c a l l y d o u b l e t h e p r e s e n t wood h a r v e s t , t h o u g h t h i s w o u l d have t o come f r o m t h e a r e a o f t h e f o r e s t c l a s s i f i e d a s t e r t i a r y b e l o w Table I I I

Forest Classification

Distance from F o r e s t I n d u s t r y Centres km

Reserved Primary Secondary Tertiary

Area

infinity

Potential for Biomass Utilization in Canada - American Chemical Society

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