Biomass Pyrolysis Technology and Products - American Chemical


Most of the oil substitution from biomass in Canada has been in light and heavy ... Canadian. Forestry Service. .... into a turbulent cloud of hot sol...
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Chapter 2

Biomass Pyrolysis Technology and Products

Downloaded by UNIV OF CALIFORNIA SAN DIEGO on November 3, 2015 | http://pubs.acs.org Publication Date: September 30, 1988 | doi: 10.1021/bk-1988-0376.ch002

A Canadian Viewpoint R. D. Hayes Renewable Energy Branch, Energy, Mines, and Resources, Ottawa, Canada K1A 0E4 By way of introduction, this paper presents four "views" on pyrolysis, including an international view, a technical review, a strategic point of view, and a general Canadian bioenergy overview. From a basic definition of pyrolysis as the thermal conversion of material in the absence of oxygen, the following discussion includes vacuum, atmospheric and pressurized pyrolysis technologies for the production of gas, liquid, or char products.

Canadian B i o e n e r g y

Overview

Canada i s w e l l endowed w i t h energy a l t e r n a t i v e s t o c o n v e n t i o n a l petroleum. A number o f these r e s o u r c e s a r e v a s t , i n c l u d i n g t a r s a n d s , a r c t i c and o f f s h o r e o i l , n a t u r a l gas, c o a l , n u c l e a r , b i o e n e r g y and o t h e r renewables. They a r e a l s o , i n g e n e r a l , e x p e n s i v e r e l a t i v e t o c u r r e n t domestic and imported l i g h t crude o i l p r i c e s . B i o e n e r g y , however, has c a r r i e d out an i m p r e s s i v e impact on Canada's p r i m a r y energy s u p p l y , by r i s i n g from 3% i n 1978 t o 6.8% i n 1987. I t s c u r r e n t c o n t r i b u t i o n s i n t h e i n d u s t r i a l and r e s i d e n t i a l s e c t o r s a r e 17% and 14%, r e s p e c t i v e l y . Most o f t h e o i l s u b s t i t u t i o n from biomass i n Canada has been i n l i g h t and heavy f u e l o i l markets. So f a r , very few o f Canada's a l t e r n a t i v e s have made much impact i n t h e t r a n s p o r t a t i o n s e c t o r , n o r a r e t h e r e any obvious e x p e c t a t i o n s o f near-term o i l s u b s t i t u t i o n i n t r a n s p o r t a t i o n o t h e r than a s m a l l n i c h e o f v e h i c l e s running on propane o r n a t u r a l g a s . A g a i n s t t h i s backdrop, Canadian b i o e n e r g y R&D i s very b r o a d l y t a r g e t t e d t o near-term o p p o r t u n i t i e s f o r n o n - t r a n s p o r t a t i o n uses and t o medium and l o n g e r term o p p o r t u n i t i e s f o r t r a n s p o r t a t i o n uses. The term " b r o a d l y " i s emphasized because t h e r e a r e e x c e p t i o n s t o this generalization. Canada's b i o e n e r g y R&D a c t i v i t i e s d i d not b e g i n i n e a r n e s t u n t i l 1978, l a g g i n g somewhat behind other p a r t s o f t h e w o r l d . I n 1980, t h e f e d e r a l N a t i o n a l Energy Program g r e a t l y i n c r e a s e d R&D f u n d i n g i n 0097-6156/88/0376-0008$06.00/0 © 1988 American Chemical Society

In Pyrolysis Oils from Biomass; Soltes, E., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1988.

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a l l c o n s e r v a t i o n and a l t e r n a t i v e energy a r e a s . B i o e n e r g y R&D e f f o r t grew t o $22 m i l l i o n (Cdn) i n 1983-84. Then as o i l p r i c e s s e t t l e d , Canada's energy R&D program e x p e r i e n c e d the "Crash of '84" the government decreased spending by 50%. Bioenergy R&D i s c u r r e n t l y c e n t r e d i n two f e d e r a l departments. Energy, Mines and Resources Canada manages the Bioenergy Development Program a t a p p r o x i m a t e l y $6 m i l l i o n (Cdn) f o r biomass c o n v e r s i o n , and a l e v e l of a p p r o x i m a t e l y $1.5 m i l l i o n (Cdn) f o r biomass p r o d u c t i o n i s managed by t h e Canadian Forestry Service. An approximate breakdown o f 1987 Bioenergy C o n v e r s i o n R&D e x p e n d i t u r e s i n g e n e r a l t e c h n o l o g y areas i s as f o l l o w s : Biochemical conversion Thermochemical c o n v e r s i o n Combustion Biomass h a n d l i n g and p r e p a r a t i o n Peat mining and p r o c e s s i n g Information t r a n s f e r

39% 16% 22% 12% 6% 5%

Of s p e c i a l i n t e r e s t t o the audience o f t h i s paper i s t h a t t h e bulk of t h e thermochemical R&D i s devoted t o some form or o t h e r of pyrolysis. H i s t o r y and S t r a t e g y , 1978-1987 Amidst the p a n i c of petroleum s h o r t a g e s and r i s i n g p r i c e s o f 1979, some i n d i v i d u a l s expected t o produce o i l s from biomass, a l s o known as b i o - c r u d e , p r o t o - o i l , bunker b i o - o i l . . . T h i s e x p e c t a t i o n was f a i r l y s h o r t - l i v e d however. A l t h o u g h t o u t e d as something, someday d e s t i n e d t o r e p l a c e o r reduce o i l i m p o r t s , p y r o l y s i s o i l from biomass had very l i t t l e i n common w i t h p e t r o l e u m . Its q u a l i f i c a t i o n s as "a crude" were very rudimentary. I t looked b l a c k , s m e l l e d bad, and u s u a l l y f l o w e d i f t h e r e was enough water i n i t ; but t h a t i s where the resemblance ended. Biomass, i n those days, was modelled by some r e s e a r c h e r s as a young c o a l , and i t s p y r o l y s i s o i l as a young o i l or a c o a l l i q u i d . N e i t h e r assumption was very a c c u r a t e . Those who f o l l o w e d c o a l l i q u e f a c t i o n development had a head s t a r t i n a p p l y i n g t h a t enormous knowledge base t o biomass. However, perhaps due t o t h a t knowledge base, e a r l y biomass p r o c e s s development d i d not f u l l y t a k e advantage of t h e unique o p p o r t u n i t y f o r s p e c i a l i z e d p r o c e s s i n g t h a t biomass c o u l d p r o v i d e . Biomass i s not a homogeneous c h e m i c a l conglomerate, but r a t h e r a composite of t h r e e major polymers namely c e l l u l o s e , h e m i c e l l u l o s e and l i g n i n . A g a i n s t t h i s background, Canadian r e s e a r c h e r s j o i n e d the i n t e r n a t i o n a l f l u r r y of r e s e a r c h a c t i v i t y i n t h i s a r e a . By 1980, t h e r e were t w e l v e l a b o r a t o r i e s , mostly u n i v e r s i t i e s , i n v o l v e d i n some v a r i a t i o n of biomass p y r o l y s i s r e s e a r c h . The major f o c u s of t h e i r work was t o produce a f u e l o r h e a t i n g o i l . There was v e r y l i t t l e work done on upgrading b i o - o i l t o a t r a n s p o r t a t i o n f u e l or ven a r e f i n e r y f e e d s t o c k . A l s o , t h e r e was l i t t l e i n t e r e s t i n the o p t i m i z e d p r o d u c t i o n of gas or char i n Canada s i n c e Canada i s b l e s s e d w i t h s u b s t a n t i a l r e s e r v e s o f n a t u r a l gas and c o a l .

In Pyrolysis Oils from Biomass; Soltes, E., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1988.

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In 1980, the f e d e r a l government embraced an " o f f - o i l " p o l i c y under the N a t i o n a l Energy Program. A number of programs p r o v i d e d a s s i s t a n c e d i r e c t l y or i n d i r e c t l y t o homeowners and i n d u s t r y f o r s u b s t i t u t i n g heavy and l i g h t f u e l o i l , by o t h e r energy forms such as n a t u r a l gas, e l e c t r i c i t y and biomass ( v i a c o m b u s t i o n ) . 3 i o - o i l was not t e c h n i c a l l y ready t o t a k e advantage of a market o p p o r t u n i t y , and more i m p o r t a n t l y , i t had no commercial or i n d u s t r i a l i n f r a s t r u c t u r e t o b u i l d upon. T h e r e f o r e , i n s p i t e o f w o r l d r e c o r d p e t r o l e u m p r i c e s , apparent s h o r t f a l l s i n imported and domestic o i l s u p p l i e s , and a p o l i c y environment t h a t was a c t i v e l y encouraging energy a l t e r n a t i v e s i n Canada, b i o - o i l became a long term c u r i o s i t y . R&D was i m p o r t a n t , but i t was supported under the o b j e c t i v e of long term s e c u r i t y of s u p p l y of l i q u i d f u e l s . Canada's R&D e f f o r t s c o n t i n u e d t o down-play upgrading over the next f o u r y e a r s and c o n c e n t r a t e d almost e x c l u s i v e l y on p r i m a r y o i l p r o d u c t i o n . By 1984, o i l p r i c e s appeared t o be more s e t t l e d and the time frame f o r c o m m e r c i a l i z i n g t r a n s p o r t a t i o n f u e l s from b i o - o i l was l i k e l y t o be w e l l beyond 2000. There appeared t o be p l e n t y of time t o p e r f e c t o i l upgrading a t a l a t e r d a t e , e i t h e r through h y d r o t r e a t i n g or u s i n g s h a p e - s e l e c t i v e z e o l i t e c a t a l y s i s . Then came t h e "Crash of '84" r e f e r r e d t o e a r l i e r . B i o e n e r g y R&D f u n d i n g r e s o u r c e s were d e c l i n i n g r a p i d l y . Government seemed t o want more near term r e s u l t s from an a l r e a d y s h r i n k i n g energy f u n d i n g base. Between 1980 and 1984, biomass p y r o l y s i s R&D f u n d i n g had been s l o w l y i n c r e a s i n g w h i l e the number o f Canadian l a b o r a t o r i e s working i n t h i s a r e a had decreased from t w e l v e t o s i x . By 1984/85 thermochemical R&D and o t h e r long-term o p t i o n s w i t h i n the Bioenergy Development Program o f Energy, Mines and Resources had become v u l n e r a b l e t o f u n d i n g r e d u c t i o n s . I t was important not t o l o s e t h e advances a l r e a d y a c h i e v e d and the w o r l d c l a s s e x p e r t i s e developed i n Canada. The d e c i s i o n was t a k e n t h e r e f o r e t o wind up the r e s e a r c h i n Canada over the next two t o t h r e e y e a r p e r i o d i n o r d e r t o l e a v e a r e t r i e v a b l e a c c o u n t i n g of developments f o r f u t u r e r e s e a r c h e r s . The second o b j e c t i v e was t o m a i n t a i n ( o r s a l v a g e ) a base c o r e of e x c e l l e n c e i n Canada a t a reduced f u n d i n g l e v e l s . T h i s d e c i s i o n d i d not u n f o l d as planned however. Three y e a r s l a t e r , the Canadian program i n p y r o l y s i s i s s t r o n g e r than e v e r . The 1987 R&D program o f work i n c l u d e s work i n f i v e o f the s i x l a b o r a t o r i e s , a t f u n d i n g l e v e l s s l i g h t l y h i g h e r than i n 1984. The f o l l o w i n g t h r e e e x p l a n a t i o n s can h e l p e x p l a i n why t h e s t r a t e g i c p l a n changed so f u n d a m e n t a l l y . 1. I n d u s t r y I n t e r e s t . One o f Canada's l e a d i n g s o l a r and biomass c o n v e r s i o n equipment companies, Petro-Sun I n t e r n a t i o n a l I n c . became i n t e r e s t e d i n s c a l i n g up the Université Laval/Université de Sherbrooke vacuum p y r o l y s i s p r o c e s s on a c o s t - s h a r e d b a s i s . S p e c i a l Note. As o f January 1988, Petro-Sun I n t e r n a t i o n a l I n c . was f o r c e d i n t o r e c e i v e r s h i p f o r reasons u n r e l a t e d t o t h e i r a c t i v i t i e s i n biomass p y r o l y s i s . The Université L a v a l i s s e e k i n g a l t e r n a t i v e i n d u s t r i a l p a r t n e r s . Another company, Ensyn E n g i n e e r ing L t d . , was e s t a b l i s h e d , and proposed a c o s t - s h a r e d , s c a l e d - u p development of the U n i v e r s i t y of Western O n t a r i o u l t r a p y r o l y s i s . S i m i l a r l y , t h e r e has been a number of i n d u s t r i a l e x p r e s s i o n s o f i n t e r e s t i n t h e U n i v e r s i t y of Waterloo f l a s h p y r o l y s i s .

In Pyrolysis Oils from Biomass; Soltes, E., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1988.

2. HAYES

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Diversification. An approach has e v o l v e d i n Canada whereby, u n l i k e e a r l i e r e f f o r t s , a whole range o f p r o d u c t s and r e a c t a n t s a r e now c o n s i d e r e d . Products include o i l s of varying q u a l i t y , sugar s o l u t i o n s i n h i g h y i e l d , c h e m i c a l s ( o l e f i n s , p h e n o l i c s , as w e l l as h i g h v a l u e s p e c i a l t y c h e m i c a l s ) , g a s o l i n e o r d i e s e l f u e l , and h i g h e r v a l u e c a r b o n . D i v e r s i f i c a t i o n of reactants i n c l u d e whole biomass (wood and s t r a w ) , f r a c t i o n a t e d biomass components, p e a t , m u n i c i p a l s o l i d waste, i n c l u d i n g used t i r e s , etc. Another important a r e a o f r e s e a r c h i s t h e t r e a t m e n t , and e s p e c i a l l y , t h e c o n v e r s i o n , o f waste aqueous e f f l u e n c e from p y r o l y s i s i n t o value-added c o - p r o d u c t c r e d i t s . Left unprocessed, t h e s e e f f l u e n c e would o t h e r w i s e i n c u r a c o s t f o r waste t r e a t m e n t . TEA C o l l a b o r a t i o n . By working t o g e t h e r w i t h t h r e e o t h e r member c o u n t r i e s o f t h e I n t e r n a t i o n a l E n e r g y Agency's B i o e n e r g y Agreement, Canada has been a b l e t o combine r e s o u r c e s w i t h USA, Sweden, and F i n l a n d t o d e t e r m i n e t h a t Canadian biomass p y r o l y s i s t e c h n o l o g i e s appear t o be as good as any i n t h e w o r l d . Canada has a l s o had i t s p y r o l y s i s o i l s upgraded and a s s e s s e d by c o l l a b o r a t o r s i n t h e USA· P r e l i m i n a r y r e s u l t s i n d i c a t e t h a t Canada s h o u l d review i t s t r a d i t i o n a l s t r a t e g y o f n o t immediately p u r s u i n g u p g r a d i n g R&D.

T e c h n i c a l Review Over t h e p a s t s e v e r a l y e a r s r e s e a r c h e r s W.J.M. Douglas and D.G. Cooper a t M c G i l l u n i v e r s i t y have been s t u d y i n g an i n t e r e s t i n g thermochemical approach t o wood l i q u e f a c t i o n u s i n g aqueous hydrogen i o d i d e i n f a i r l y m i l d c o n d i t i o n s o f p r e s s u r e and temperature (125°C). S t i l l f a r from c e r t a i n i s t h e e x a c t n a t u r e o f t h e l i q u i d p r o d u c t s and t h e techno-economic p r a c t i c a l i t y o f hydrogen i o d i d e r e c o v e r y and r e c y c l e . On t h e p o s i t i v e s i d e , i n a d d i t i o n t o t h e low s e v e r i t y c o n d i t i o n s o f r e a c t i o n , t h e p r o c e s s removes about 80% o f the oxygen i n t h e wood, and t h e c h a r y i e l d i s v e r y low. D.G.B. Boocock and co-workers a t t h e U n i v e r s i t y o f T o r o n t o have u n d e r t a k e n t h e i n v e s t i g a t i o n o f a steam p y r o l y s i s o r h y d r o t h e r m o l y s i s o f wood. Based on t h e i r e a r l i e r work, they r e c e n t l y d e s i g n e d and c o n s t r u c t e d a l a b o r a t o r y s c a l e c a s c a d e a u t o c l a v e which c a n accommodate up t o 100 g o f wood c h i p s o r 170g o f a s i n g l e l a r g e r p i e c e (3.8 cm r e a c t o r I.D., 600ml volume). It i s r a t e d a t 24.1 MPa (3500 p s i . ) a t 350°C a l l o w i n g f o r 7.6 MPa (1100 p s i ) gas o v e r p r e s s u r e above t h e vapour p r e s s u r e o f water a t t h a t temperature. R e s u l t s t o d a t e a r e p r e l i m i n a r y s i n c e t h e u n i t was commissioned o n l y i n e a r l y 1987. Reproduced r e s u l t s i n d i c a t e t h a t o i l y i e l d i n c r e a s e s with increased c h i p s i z e . Product o i l y i e l d s a r e v e r y h i g h (up t o 50%) w i t h no s o l i d s c o n t a m i n a t i o n , and t h e o i l i s e a s i l y s e p a r a b l e from t h e aqueous phase. Coupled w i t h an upgrading p r o c e s s , t h i s t e c h n o l o g y may someday w e l l l e n d i t s e l f w e l l to commercialization. I n a d d i t i o n t o t h e i r p r o c e s s development work, Boocock's group has c o n t r i b u t e d g r e a t l y t o t h e b a s i c u n d e r s t a n d i n g o f biomass l i q u e f a c t i o n , e s p e c i a l l y through t h e i r s c a n n i n g e l e c t r o n m i c r o s c o p i c s t u d i e s . Of p o t e n t i a l i n t e r e s t t o o i s t h e i r d i s c o v e r y i n 1984 t h a t a p a r t i c u l a r c l o n e o f h y b r i d p o p l a r y i e l d e d 6% p h e n o l .

In Pyrolysis Oils from Biomass; Soltes, E., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1988.

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Ε . Chornet, R.P. Overend and co-workers a t t h e Université de Sherbrooke have been working on a l i q u e f a c t i o n p r o c e s s i n p r e s s u r i z e d s o l v e n t f o r some y e a r s . T h e i r approach i n v o l v e s an o v e r a l l i n t e g r a t i o n o f biomass p r e t r e a t m e n t , f r a c t i o n a t i o n , a c i d p r o c e s s i n g , thermochemical and b i o c h e m i c a l t r e a t m e n t . D.S. S c o t t , J . P i s k o r z , D, R a d l e i n and co-workers a t t h e U n i v e r s i t y o f Waterloo a r e w e l l known f o r t h e i r f l u i d i z e d bed f l a s h p y r o l y s i s development, a l s o known as t h e WFPP (Waterloo P a s t P y r o l y s i s P r o c e s s ) . The WPPP a c t u a l l y i n c l u d e s f o u r p r o c e s s o p t i o n s as f o l l o w s : 1. D i r e c t t h e r m a l p r o c e s s i n g a t 450-550°C, atmospheric p r e s s u r e and about 500 ms vapour r e s i d e n c e t i m e . They r e p o r t t h e h i g h e s t l i q u i d y i e l d s (80% i n c l u d i n g water, based on i n p u t wood) t h a t i s a suitable f u e l f o r conventional b o i l e r s . 2. By v a r y i n g t h e p r o c e s s c o n d i t i o n s and a d o p t i n g a m i l d s u l p h u r i c a c i d p r e t r e a t m e n t f o l l o w e d by f l u i d i z e d bed t h e r m o p y r o l y s i s , t h e WPPP produces a h i g h y i e l d and c o n c e n t r a t i o n o f a n h y d r o - o l i g o s a c c h a r i d e s , mostly l e v o g l u c o s a n r a t h e r than o i l p r o d u c t s . T h e i r r e p r o d u c i b l e y i e l d s o f sugars from pure c e l l u l o s e a r e about 80% i n a c o n c e n t r a t e d form. One c a n e a s i l y s p e c u l a t e whether t h i s development c o u l d c h a l l e n g e some o f t h e e q u a l l y e x c i t i n g b i o c o n v e r s i o n methods o f c o n v e r t i n g l i g n o c e l l u l o s i c s t o fermentable sugars. 3. Waterloo's h y d r o g a s i f i c a t i o n work has been t e c h n i c a l l y h i g h l y s u c c e s s f u l , r e s u l t i n g i n 75% c o n v e r s i o n o f carbon from wood t o methane v i a p y r o l y s i s over a n i c k e l - a l u m i n a c a t a l y s t w i t h hydrogen a t about 550°C and 440 ms r e s i d e n c e t i m e . 4. Under c u r r e n t i n v e s t i g a t i o n i s a f o u r t h p r o c e s s o p t i o n s o f p r o d u c i n g u n s a t u r a t e d hydrocarbons i n a c a t a l y s e d r e a c t i o n . A p a r t from t h e use of c a t a l y s t s , t h e p r o c e s s equipment and o p e r a t i n g c o n d i t i o n s a r e very s i m i l a r f o r a l l o f t h e above process o p t i o n s . M. Bergougnou, R. Graham and co-workers have developed an U l t r a - R a p i d P y r o l y s i s or U l t r a p y r o l y s i s process at the U n i v e r s i t y of Western O n t a r i o . A l t h o u g h t h e r e a r e s i m i l a r i t i e s i n t h i s work and the r e s e a r c h a t t h e U n i v e r s i t y o f W a t e r l o o , t h e r e a r e important d i f f e r e n c e s . Whereas Waterloo u t i l i z e s f l u i d i z e d bed heat t r a n s f e r , Bergougnou employees a very r a p i d (30ms) m i x i n g and heat t r a n s f e r i n a v o r t i c a l c o n t a c t o r o r v o r t a c t o r f o l l o w e d by a p l u g - f l o w e n t r a i n e d bed down f l o w r e a c t o r (50-900ms) and quenching (30ms) w i t h c r y o g e n i c n i t r o g e n i n a c r y o v o r t a c t o r . A l s o d i s s i m i l a r t o t h e Waterloo p r o c e s s a r e t h e p r o c e s s c o n d i t i o n s (650-1000°C, 50-900 ms r e s i d e n c e time) and t h e main product a t t h e s e temperatures i s gas r a t h e r than liquid. S i n c e p y r o l y t i c f u e l gas p r o d u c t i o n has not been o f h i g h p r i o r i t y i n Canada's b i o e n e r g y R&D s t r a t e g y , t h e c u r r e n t o b j e c t i v e , i n c o l l a b o r a t i o n w i t h Ensyn E n g i n e e r i n g , i s c h e m i c a l p r o d u c t i o n , olefins i n particular. Tt i s i n t e r e s t i n g t o note here t h a t t h e U n i v e r s i t i e s o f Waterloo and Western O n t a r i o conducted an experiment of d a t a comparison from each o f t h e i r r e a c t o r systems. U s i n g s e l e c t e d d a t a from both groups at around 500 ms r e s i d e n c e t i m e , l i q u i d and gas p r o d u c t i o n d a t a were p l o t t e d vs temperature. The temperature ranges were as f o l l o w s : Waterloo a t 400°-750°C, and Western O n t a r i o a t 650°-900°C. With combined d a t a f o r each o f t h e gas y i e l d vs temperature and l i q u i d

In Pyrolysis Oils from Biomass; Soltes, E., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1988.

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2.

HAYES

Biomass Pyrolysis Technology and Products

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y i e l d vs temperature d a t a , t h e r e was, as expected, c o n s i d e r a b l e c o n c u r r e n c e o f o v e r l a p p i n g d a t a . In f a c t a s i m p l e f i r s t o r d e r k i n e t i c model i s a b l e t o d e s c r i b e the o i l y i e l d over t h e temperature range o f both e x p e r i m e n t s , Rnsyn E n g i n e e r i n g i s a r e c e n t l y formed company whose p r i n c i p a l i n v e s t i g a t o r , R. Graham has s c a l e d up the u n i v e r s i t y of Western O n t a r i o U l t r a p y r o l y s i s r e a c t o r by a f a c t o r o f 20 t o a 5-10 kg/hr c a p a c i t y RTP ( R a p i d Thermal P r o c e s s o r ) , The r e a c t o r i s designed t o accept any carbonaceous feed ( s o l i d , l i q u i d , or gas) by i n j e c t i n g i n t o a t u r b u l e n t c l o u d of hot s o l i d s . The mixed f e e d p l u s s o l i d s i s c a r r i e d through a t u b u l a r t r a n s p o r t r e a c t o r t o an i n e r t i a l s e p a r a t o r where vapour p r o d u c t s a r e removed. R e s u l t s t o date a r e very p r e l i m i n a r y . The concept f o r m u l a t e d by Ensyn i s t h a t t h e RTP would be a c e n t r a l p r o c e s s o r of p r i m a r y p y r o l y s i s o i l s from s m a l l e r , perhaps m o b i l e , p l a n t s . The m u l t i - s t a g e vacuum p y r o l y s i s was developed by C. Roy and co-workers, i n i t i a l l y at the Université de Sherbrooke and, c u r r e n t l y , a t the Université L a v a l . In c o l l a b o r a t i o n w i t h Petro-Sun I n t e r n a t i o n a l I n c . t h e r e i s a p i l o t d e m o n s t r a t i o n of a s i n g l e - s t a g e p l a n t at St-Amable, Quebec. The u n i t has a c a p a c i t y of 200 kg/hr and i s designed f o r used t i r e s . The t e c h n o l o g y i s based on a m u l t i p l e h e a r t h vacuum p y r o l y s i s p r o c e s s development u n i t l o c a t e d near t h e Université L a v a l and o p e r a t i n g at a 30 kg/hr biomass capacity. A l t h o u g h the m u l t i p l e h e a r t h concept s u f f e r s from low heat t r a n s f e r r e l a t i v e t o o t h e r p y r o l y s i s p r o c e s s e s , and, a t f i r s t g l a n c e , i s c a p i t a l c o s t i n t e n s i v e , i t has a number of f e a t u r e s t h a t show commercial promise as f o l l o w s : 1. A r e a s o n a b l y h i g h y i e l d of p y r o l y s i s o i l (50% based on wood). 2. The p r o d u c t i o n of co-product c a r b o x y l i c a c i d s and h i g h v a l u e chemicals. 3. R e a c t i v e c h a r c o a l a t 25% of i n p u t wood. 4. The aqueous phase i s recovered s e p a r a t e l y as p a r t of the p r o c e s s l e a v i n g a w a t e r - f r e e p y r o l y s i s o i l ready f o r u p g r a d i n g . 5. The m u l t i p l e h e a r t h performs a product f r a c t i o n a t i o n f u n c t i o n t h a t c o u l d reduce e x t r a c t i o n c o s t s of h i g h v a l u e c h e m i c a l s . Centralized Analysis One f i n a l work of i n t e r e s t i n Canada i s the C e n t r a l i z e d A n a l y s i s p r o j e c t at B.C. Research. I n 1984, a t r i a l p r o j e c t was set-up whereby d i f f e r e n t Canadian b i o - o i l s c o u l d be compared i n a c o n s i s t e n t manner. The p r o j e c t embraced a three-pronged approach. Under t h e guidance o f J . Howard and J . M c K i n l e y , B.C. Research performed and/or c o o r d i n a t e d the c e n t r a l i z e d a n a l y s e s o f o p t i m i z e d o i l s produced by each r e s e a r c h e r . I f a p a r t i c u l a r a n a l y t i c a l c a p a b i l i t y was not a v a i l a b l e a t B.C. R e s e a r c h , another l a b o r a t o r y w i t h t h a t s t r e n g t h was c o n t r a c t e d t o do i t . I n d i v i d u a l r e s e a r c h e r s a l s o d i d some of t h e i r own a n a l y s e s t o o b t a i n immediate e x p e r i m e n t a l feedback. The second prong o f the approach was t h a t a l l r e s e a r c h e r s were p r o v i d e d w i t h a s t a n d a r d wood sample Populus deltoïdes by P o r i n t e k Canada Corp. The i d e a was t h a t when each p r o c e s s development became somewhat o p t i m i z e d , the r e s e a r c h e r would submit o i l from the s t a n d a r d wood sample t o the c e n t r a l i z e d a n a l y s i s team.

In Pyrolysis Oils from Biomass; Soltes, E., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1988.

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PYROLYSIS OILS FROM BIOMASS The t h i r d prong was a computer communications network l i n k c a l l e d CoSy, through the u n i v e r s i t y o f Guelph, t o p r o v i d e f a s t communication of a n a l y t i c a l d a t a . I t was a l s o used t o encourage m u l t i l a t e r a l and b i l a t e r a l c o l l a b o r a t i o n and problem s o l v i n g . The c e n t r a l i z e d a n a l y s i s p r o j e c t i s e n t e r i n g Phase I I . Learning from the s u c c e s s e s and p i t f a l l s of the f i r s t two and one h a l f y e a r s , the scope of t h i s p r o j e c t has changed somewhat. The consensus of program managers and r e s e a r c h e r s i s t h a t Phase I I w i l l have two major t a s k s . Task 1 i s a s e t o f a n a l y t i c a l t e c h n i q u e s a l o n g the same l i n e s as the i n i t i a l p r o j e c t except the methods t h a t were c o n s i d e r e d t o be l e s s i n t e r e s t i n g t o the e n t i r e group a r e not i n c l u d e d . The b a s i c a n a l y s e s i n c l u d e the f o l l o w i n g : -

Elemental

-

Water Content Density Carboxylic Acids Gas L i q u i d Chromatography Carbon-13 NMR G e l P e r m e a t i o n Chromatography

Analysis

Task 2 c o n s i s t s l a r g e l y of s p e c i a l a n a l y t i c a l p r o j e c t s t o meet the needs of i n d i v i d u a l s or groups of thermochemical c o n v e r s i o n r e s e a r c h e r s t h a t may a r i s e over the next two years. I n t e r n a t i o n a l View -

IEA

Under the I n t e r n a t i o n a l E n e r g y Agency, e l e v e n c o u n t r i e s s i g n e d a t h r e e y e a r B i o e n e r g y Implementing Agreement, e f f e c t i v e January 1, 1986 - December 31, 1988. Canada, USA, Sweden and F i n l a n d agreed t o c o l l a b o r a t e on a p r o j e c t e n t i t l e d D i r e c t Biomass L i q u e f a c t i o n (DBL). A Working Group o f e n g i n e e r s and o t h e r s p e c i a l i s t s a r e p r e p a r i n g a d e t a i l e d t e c h n i c a l - e c o n o m i c assessment (TEA) f o r s c a l e - u p and o p e r a t i o n a t commercial s i z e , o f the most p r o m i s i n g h i g h and low p r e s s u r e p y r o l y s i s p r o c e s s e s . Both p r i m a r y o i l p r o d u c t i o n and upgrading a r e c o n s i d e r e d i n the TEA. The u p g r a d i n g work on Canadian a t m o s p h e r i c and vacuum p y r o l y s i s o i l s has been conducted by D. E l l i o t a t B a t e l l e P a c i f i c Northwest L a b o r a t o r i e s . Y i e l d s of p r o d u c t s i n the g a s o l i n e b o i l i n g range have so f a r reached 35% of p r i m a r y o i l by h y d r o t r e a t i n g . The Working Group i s a t t e m p t i n g two t y p e s of a n a l y s e s , one based on c u r r e n t s t a t e of the a r t and the second based on p r o j e c t e d improvements and developments i n the technologies. Canada has b e n e f i t t e d g r e a t l y from t h i s p r o j e c t . In a f u n d i n g environment t h a t r e s t r i c t e d major t h r u s t s i n u p g r a d i n g R&D i n Canada's n a t i o n a l program, t h e r e i s t h i s element a v a i l a b l e i n the i n t e r n a t i o n a l program. Another b e n e f i t t o Canada i s t h a t the IEA Working Group, independent of s e l f - i n t e r e s t s or b i a s e s toward the v a r i o u s processes, concluded that Canadian primary p y r o l y s i s o i l s have t e c h n i c a l and economic advantages t o o t h e r p r o c e s s e s under development.

In Pyrolysis Oils from Biomass; Soltes, E., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1988.

2. HAYES

Biomass Pyrolysis Technology and Products

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Acknowledgments The a u t h o r wishes t o acknowledge the v a r i o u s r e s e a r c h e r s a c r o s s Canada w i t h o u t whose i d e a s , open d i s c u s s i o n , and d e d i c a t i o n t o r e s e a r c h i n thermochemical c o n v e r s i o n o f biomass, t h i s paper would not have been p o s s i b l e . Each has c o n t r i b u t e d t o t h i s paper, e i t h e r d i r e c t l y or i n d i r e c t l y . The f o l l o w i n g l i s t i s not c o m p l e t e , but i n c l u d e s t h e p r i n c i p a l i n v e s t i g a t o r s i n Canadian l a b o r a t o r i e s and other notable i n t e r n a t i o n a l c o l l a b o r a t o r s . In a l p h a b e t i c a l order, many thanks t o Narendra B a k h s h i , Dave Beckman, Dave Boocock, Jean Bouchard, M a u r i c e Bergougnou, E s t e b a n C h o r n e t , Helena Chum, J i m D i e b o l d , Murray D o u g l a s , D i c k E a g e r , Doug E l l i o t , Bob Graham, John Howard, Serge K a l i a g u i n e , B j o r n K j e l l s t r o m , Tom M i l n e , Hugh Menard, J i m M c K i n l e y , R a l p h Overend, Hooshang P a k d e l , J i m Pepper, Jan P i s k o r z , Desmond R a d l e i n , Tom Reed, C h r i s t i a n Roy, Don S c o t t , Jacques S i c o t t e , and t h e i r many c o l l e a g u e s , s t a f f , and s t u d e n t s . References This paper contains technical contributions from a l l the Canadian and other work mentioned here. The reader is referred to these articles as primary references. RECEIVED June 10,

1988

In Pyrolysis Oils from Biomass; Soltes, E., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1988.

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