9 Recent Developments in the Swedish Pulp and Paper Industry INGVAR JULLANDER Swedish Forest Products Research Laboratory, Box 5604, S-114 86 Stockholm 5, Sweden
The pulp and paper industries in different countries, especially those in the industrialized world, are tied together in many ways. To some extent they compete with each other through their products. An important factor in their technical development is that machine and instrument suppliers of reasonable size are always looking for markets all over the world, so that technical novelties spread rapidly and efficiently. Research specialists in different fields also form a truly international brotherhood exchanging views and discussing their problems at symposia, during congresses and through personal visits. The important problem areas are the same all over the world. Nevertheless the actual direction from which a problem is attacked may differ between countries. The raw material situation, for example, varies from the availability of large, still untapped forestry resources to a pulp and paper industry, substantially based on imported wood. Finland, Norway, and Sweden, the three Scandinavian pulp and paper producing countries, all have similar climates and geological histories. As a consequence our forests contain the same botanical species; one type of spruce, one type of pine (in the foreseeable future there will be two types of pine available in our forests) and also birch. The technical problems associated with the processing of wood to pulp and paper and the problems involved in marketing these products are therefore very similar in these three countries. A few statistics will indicate how the Swedish 184
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f o r e s t p r o d u c t s i n d u s t r i e s r a t e i n the w o r l d and i n the i n t e r n a l economy o f our c o u n t r y . In Sweden the p r o d u c t i o n o f market p u l p i n c r e a s e d 2.3 times between 1950 and 1974, whereas i n the same p e r i o d paper p r o d u c t i o n i n c r e a s e d no l e s s than 4.7 times. In o t h e r words, t h e r e was a steady t r e n d t o wards g r e a t e r i n t e g r a t i o n o f p u l p m i l l s w i t h paper mills. T h i s tendency i s s t i l l s t r o n g . Sweden's p o s i t i o n i n t h e w o r l d as a paper producing r e g i o n i s modest. Sweden i s much more important i n t h e w o r l d p u l p t r a d e , c o v e r i n g about 50% o f the demand from S c a n d i n a v i a and North America t o g e t h e r . The steady and dominant market f o r Sweden i s Western Europe which consumes 85% o f our p u l p and paper export. It has become common p r a c t i c e t o compare the p e r c a p i t a consumption o f paper and paper p r o d u c t s i n d i f f e r e n t c o u n t r i e s and t o use t h i s f i g u r e as a measure of the e c o n o m i c a l h e a l t h o f a c o u n t r y . T h i s measure i s open t o c r i t i c i s m l i k e a l l o t h e r measures o f the standard of l i v i n g . I t may be o f i n t e r e s t t o compare a l s o the p e r c a p i t a e x p o r t o f market p u l p p l u s p a p e r . T h i s f i g u r e can be used as a q u a n t i t a t i v e measure o f the n a t i o n a l importance o f the f o r e s t p r o d u c t s i n d u s try . I s h a l l now b r i e f l y c o n s i d e r the importance o f the whole o f the f o r e s t p r o d u c t s i n d u s t r y t o t h e nat i o n a l economy. In 1973 the i n d u s t r y accounted f o r 24% o f the v a l u e o f a l l e x p o r t s . T h i s p e r c e n t a g e has s t e a d i l y d e c r e a s e d s i n c e the 1950's i n s p i t e o f a cons i d e r a b l e r i s e i n p r o d u c t i o n . The f o r e i g n exchange earned d u r i n g 1974 by the f o r e s t p r o d u c t s i n d u s t r y p a i d our t o t a l o i l b i l l and i n a d d i t i o n c o v e r e d the f o o d d e f i c i t and s t i l l l e f t some money f o r v a c a t i o n i n g abroad. F i v e problem a r e a s a r e c l e a r l y e v i d e n t : capital c o s t o f e x t e n d i n g c a p a c i t y and m o d e r n i z i n g e x i s t i n g plants; labor p r o d u c t i v i t y ; wood s u p p l y ; energy consumption; e n v i r o n m e n t a l problems, e s p e c i a l l y water and a i r . You w i l l note t h a t n e i t h e r q u a l i t y nor mark e t i n g problems a r e l i s t e d above. With a steady 85% of the e x p o r t market i n Western Europe, which i s a d e f i c i t a r e a as f a r as the f i b r e s u p p l y i s concerned, we s h o u l d not need t o worry about the market. Of c o u r s e we a r e then s i l e n t l y but c o n f i d e n t l y assuming
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t h a t our i n d u s t r y w i l l c o n t i n u e t o be a b l e t o produce the goods a t i n t e r n a t i o n a l l y a c c e p t a b l e p r i c e s . I s h a l l now d i s c u s s t h e s e problem a r e a s t o some e x t e n t and I s h a l l g i v e a few examples o f t e c h n i c a l a c t i v i t i e s o f d i f f e r e n t k i n d s w i t h i n them. C a p i t a l C o s t s . The r a p i d l y r i s i n g c a p i t a l c o s t s a r e a headache w e l l known not o n l y t o p u l p and paper manufacturers everywhere but a l s o t o t h e heavy chemic a l i n d u s t r y and o t h e r i n d u s t r i e s as w e l l . The chances a r e , however, t h a t i n t h e p u l p and paper f i e l d something s u b s t a n t i a l can be done about i t . Much o f the p r o c e s s i n g e s s e n t i a l l y means h a n d l i n g l a r g e quant i t i e s o f water c o n t a i n i n g an amount o f f i b e r which i n some o p e r a t i o n s i s below 1 %. Dry f o r m i n g of c u r r e n t paper g r a d e s , a s i d e from s p e c i a l p r o d u c t s , i s a d e f i n i t e l y i n t e r e s t i n g but s t i l l f a r away s o l u t i o n . Aw a t i n g t h i s f i n a l s o l u t i o n - i f i t ever comes - a development from the Swedish F o r e s t P r o d u c t s Research Laboratory i s of i n t e r e s t . I t w i l l enable the amount o f water h a n d l e d i n the f o r m a t i o n o f p a p e r on the mac h i n e t o be d i m i n i s h e d by a f a c t o r o f between 5 and l e t The b a s i c p r i n c i p l e o f t h i s h i g h c o n s i s t e n c y sheet f o r m i n g method i s demonstrated. The f i b r e s u s p e n s i o n e n t e r s a c r o s s machine d i s t r i b u t o r from which a number o f c y l i n d r i c a l h o l e s l e a d i n t o the a c t u a l f o r m i n g zone, T h i s c o n s i s t s o f one sharp bend and a number o f smooth bends. The energy consuming m i c r o t u r b u l e n c e c r e a t e d by the f i r s t bend i s h i g h enough t o break down the fibre floes. A v e r y low c h a n n e l h e i g h t , o f the o r d e r o f 1 t o 2 mm, p r e v e n t s any s e r i o u s r e f l o c c u l a t i o n d u r i n g t h e f l o w through the l a t e r p a r t o f the f o r m i n g s e c t i o n and the decay c h a n n e l . Here the f i b r e s form a network o f c o n s i d e r a b l e m e c h a n i c a l s t r e n g t h , p r o v i d i n g the f i b r e c o n s i s t e n c y i s s u f f i c i e n t l y h i g h . Expressed i n another way, t h e f i b r e s form a s i n g l e f l o e - the f u t u r e paper s h e e t . T h i s l i m i t s t h e lowest c o n s i s t e n cy o f up t o 5% has been used s u c c e s s f u l l y , and even t h i s w i l l not be an upper l i m i t . The l i m i t i s genera l l y s e t by the p u l p f e e d i n g system, i n c l u d i n g pumps, s t o r a g e tanks e t c . The sheet i s thus formed i n t h e head-box i n s t e a d o f on t h e w i r e as i n t h e c o n v e n t i o n a l method. F o l l o w i n g s m a l l - s c a l e t r i a l s a 900 mm wide flow-box was b u i l t and p l a c e d on top o f t h e w i r e o f our e x p e r i m e n t a l paper machine, j u s t b e f o r e the dandy
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roll.
I t was f e d d i r e c t l y from t h e machine c h e s t . A f t e r e x t e n s i v e t r i a l s on our e x p e r i m e n t a l mac h i n e , a 2.6 m wide flow-box f o r i n d u s t r i a l use has been c o n s t r u c t e d and b u i l t by our l i c e n c e h o l d e r , A A h l s t r o m Oy o f F i n l a n d . I t has been i n s t a l l e d on a f i n e paper machine i n one o f t h e i r m i l l e s i n F i n l a n d . On February 19, 1975, i t was s t a r t e d up f o r t h e f i r s t time, and w i t h i n 5 minutes paper was b e i n g r e e l e d up. The f o r m a t i o n o f t h e paper i s comparable w i t h t h a t obt a i n e d on c o n v e n t i o n a l paper machines. Subsequent runs on t h e f i n e paper machine have shown t h a t t h e h i g h c o n s i s t e n c y head-box i s v e r y easy to operate. The r e l a t i v e l y h i g h p r e s s u r e drop i n t h e head-box c o n t r i b u t e s t o an extremely u n i f o r m c r o s s direction profile. I t has a l s o been e s t a b l i s h e d t h a t t h e p r e s s i n g and d r y i n g i s improved. The s o l i d s cont e n t a f t e r t h e p r e s s s e c t i o n r o s e from 40% w i t h c o n v e n t i o n a l f o r m i n g t o 44% when a 135 g/m grade was r u n . The f e l t e d sheet s t r u c t u r e a l s o a f f e c t s t h e mec h a n i c a l p r o p e r t i e s of the sheet. The s t r e n g t h i n t h e z - d i r e c t i o n , i . e . p e r p e n d i c u l a r to the plane o f the s h e e t , i s g e n e r a l l y i n c r e a s e d by a f a c t o r o f two. As a r e s u l t of t h i s increased r e s i s t a n c e to delamination, t h e compression s t r e n g t h i n t h e p l a n e o f a h i g h c o n s i s t e n c y sheet i s h i g h e r than t h a t o f a c o n v e n t i o n a l sheet. T h i s i s e x p l a i n e d by t h e f a c t t h a t f a i l u r e i n compression i s caused by d e l a m i n a t i o n . On t h e o t h e r hand a r e d u c t i o n i n b r e a k i n g l e n g t h amounting t o 30% has been measured. T h i s r e d u c t i o n w i l l be d e c r e a s e d as a r e s u l t o f a f u r t h e r development o f t h e formers t o o b t a i n an even b e t t e r f o r m a t i o n . I t has been shown, u s i n g a new h i g h c o n s i s t e n c y handsheet former, t h a t t h e l o s s i s b r e a k i n g l e n g t h due t o t h e f e l t e d sheet s t r u c t u r e need not exceed 10%. Sheet t h i c k n e s s i s i n c r e a s e d compared w i t h t h a t o f conventional sheets. T h i s makes t h e c e n t r e p l y o f board p r o d u c t s an i d e a l a p p l i c a t i o n . The 2.6 m wide i n d u s t r i a l head-box has a l s o been s u c c e s s f u l l y u s e d i n that a p p l i c a t i o n . High c o n s i s t e n c y f o r m i n g can a l s o be a p p l i e d t o s e v e r a l o t h e r types o f p a p e r , i n c l u d i n g c o r r u g a t i n g medium and l i n e r and c o n s i d e r a b l e s a v i n g s a r e e x p e c t e d both i n investment and i n o p e r a t i n g c o s t s . The c h a n n e l i n t h e head-box i s v e r y narrow. I t t h e r e f o r e became n e c e s s a r y t o d e v e l o p a h i g h 2
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c o n s i s t e n c y s c r e e n c a p a b l e o f removing p a r t i c l e s which would o t h e r w i s e b l o c k t h e c h a n n e l . The s c r e e n i s r e q u i r e d t o work at c o n s i s t e n c i e s up t o 5 % , p r e f e r a b l y even h i g h e r . Such a s c r e e n i s a l s o d e s i r a b l e a f t e r an i n - l i n e r e f i n i n g stage f o l l o w i n g a continuous k r a f t d i g e s t e r , as w e l l as i n the s c r e e n room. A h i g h c o n s i s t e n c y b a r r i e r s c r e e n has now been d e v e l o p e d , a l s o at our i n s t i t u t e . The l a b o r a t o r y p r o t o t y p e has been r u n n i n g w e l l a t 5 % c o n s i s t e n c y . The s c r e e n i s b e i n g f u r t h e r d e v e l o p e d f o r f i n e s c r e e n i n g p u r p o s e s i n coope r a t i o n w i t h Sunds AB, Sweden. Labor P r o d u c t i v i t y . The d e s i r e t o i n c r e a s e the l a b o r p r o d u c t i v i t y i s not new. Considerable gains have been a c h i e v e d i n f o r e s t r y as w e l l as i n t h e f o r est products i n d u s t r i e s . The number o f man hours r e quired per m o f pulpwood ready f o r t r a n s p o r t a t i o n dec r e a s e d i n the y e a r s . The Swedish f o r e s t s a r e t o 5 0 % i n p r i v a t e ownership, t h e r e s t b e i n g d i v i d e d i n e q u a l p a r t s between the government and l o c a l m u n i c i p a l i t i e s on the one hand and the f o r e s t p r o d u c t s i n d u s t r y on the o t h e r . P r o d u c t i v i t y i n the p u l p and paper i n d u s t r y has i n c r e a s e d a c c o r d i n g to a s i m i l a r p a t t e r n , mainly through a p p l i c a t i o n o f t h e p r i n c i p l e o f economy o f scale. The r a p i d l y i n c r e a s i n g use o f computers f i r s t as a p r o c e s s i n g a i d and l a t e l y a l s o i n p r o d u c t i o n p l a n n i n g has, o f c o u r s e , a l s o been an important f a c t o r . Among r e c e n t t e c h n i c a l developments I s h o u l d l i k e h e r e to mention a new a n a l y t i c a l t e c h n i q u e which i n f a c t has a r e l e v a n c e to the p r o d u c t i v i t y problem a r e a . When l i q u o r s o f d i f f e r e n t k i n d s used i n o r o b t a i n e d from d i f f e r e n t p u l p i n g p r o c e s s e s a r e a n a l y s e d , t h e u s u a l p r o c e d u r e i s t o add something which r e a c t s w i t h one o f the components, the amount o f p r o d u c t formed b e i n g measured p h y s i c a l l y by a s u i t a b l e method. More o f t e n than not heat i s e v o l v e d i n the r e a c t i o n . Everybody knows t h a t t h e thermometer i s one o f our o l d e s t and most r e l i a b l e p r e c i s i o n i n s t r u m e n t s . Why not measure the temperature i n c r e a s e i n s t e a d ? With t h i s s i m p l e r e a s o n i n g as background a Swedi s h company, MoDoCell AB i n n o r t h e r n Sweden has t o g e t h e r w i t h an i n s t r u m e n t company d e v e l o p e d a c o n t i n uous c a l o r i m e t r i c a n a l y s e r (not c o l o r i m e t r i c ) . The r e a c t i o n c o n d i t i o n s a r e n e i t h e r i s o t h e r m a l nor 3
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a d i a b a t i c and t h e method can b e s t be d e s c r i b e d as a s t e a d y - s t a t e f l o w c a l o r i m e t e r . The temperature o f the s u r r o u n d i n g water b a t h must be kept c o n s t a n t w i t h i n +0.001° C. I t does not matter i f the water bath changes i t s temperature v e r y s l o w l y . The method has been used f o r a number o f a n a l y t i c a l problems such as the d e t e r m i n a t i o n o f e f f e c t i v e a l k a l i i n black liquor, of chlorate i n c h l o r i n e d i o x i d e p r o d u c t i o n , o f r e s i d u a l c h l o r i n e i n the c h l o r i n e bleaching of pulp. A f u l l d e s c r i p t i o n w i l l be g i v e n at the TAPPI b l e a c h i n g c o n f e r e n c e i n 1976. Wood S u p p l y . D e f i n i t e l y t h e most p r e s s i n g p r o b lem today f o r the Swedish f o r e s t p r o d u c t s i n d u s t r y as a whole i s t h e problem o f e n s u r i n g the a v a i l a b i l i t y o f wood raw m a t e r i a l . When we t a l k l o o s e l y about s h o r t a g e o f wood t h i s must be u n d e r s t o o d i n a c o r r e c t way. F o r t h e g r e a t e r p a r t o f t h i s c e n t u r y our c a p i t a l o f wood has i n c r e a s e d . From t h e 1920's u n t i l today our r e s o u r c e s have i n c r e a s e d by almost 40%. T h i s means t h a t we now have f o r e s t r e s e r v e s - a growing and renewable r e s o u r c e - which a r e almost c e r t a i n l y l a r g e r than a t any time i n our h i s t o r y . Our p r e s e n t d i f f i c u l t i e s s h o u l d be d i s c u s s e d from t h i s s t a r t i n g p o i n t . F i r s t l y , an a c c e l e r a t e d expansion o f our f o r e s t p r o d u c t s i n d u s t r y i n t h e l a s t 10-20 y e a r s has now caught up w i t h t h e a n n u a l p r o d u c t i o n o f wood i n t h e f o r e s t s and i t i s a m a t t e r o f debate whether or not i t has even s l i g h t l y exceeded i t . S e c o n d l y , t h e r e i s unf o r t u n a t e l y a s t a t i s t i c a l d i s t r i b u t i o n o f the age o f t h e t r e e s which i n a few decades w i l l l e a d t o a temp o r a r y d e c r e a s e i n t h e amount o f wood s u i t a b l e f o r c u t t i n g . Remember t h a t the age o f the t r e e s when a f o r e s t i s c l e a r e d i s u s u a l l y somewhere between 70 and lOO y e a r s . S t r o n g i n i t i a t i v e s have been taken i n s e e k i n g remedies; f o r example, i n c r e a s e d f e r t i l i z a t i o n i n t h e f o r e s t s and more e f f i c i e n t use o f the t r e e s - i n c l u d i n g t h e t o p s , b r a n c h e s , stumps, and r o o t s . T h i s method o f e x t e n d i n g our raw m a t e r i a l s u p p l y d i d not appear t o be e c o n o m i c a l l y f e a s i b l e some y e a r s ago but the s i t u a t i o n was s u b s t a n t i a l l y improved by t h e p r i c e i n c r e a s e s f o r p u l p and paper i n 1973-74. Energy Consumption. Sweden i s v e r y dependent on imported o i l . We have no o i l , p r a c t i c a l l y no c o a l and
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the h y d r o e l e c t r i c power cannot be i n c r e a s e d v e r y much. Energy p r i c e s have always been h i g h and as a r e s u l t the p u l p and paper p r o c e s s i n g i n d u s t r y was even b e f o r e the o i l c r i s i s w e l l r a t i o n a l i z e d w i t h r e g a r d t o energy consumption. S t i l l , o f c o u r s e , t h e sudden p r i c e i n c r e a s e o f o i l makes i t d e s i r a b l e t o save energy through c o n t i n ued s t r e a m l i n i n g o f t h e p r o c e s s e s wherever p o s s i b l e . S i n c e 1975 t h e p o l i t i c a l s i t u a t i o n e n t e r s i n t o t h e p i c t u r e i n a u n i q u e way. In t h e s p r i n g o f 1975, t h e Swedish P a r l i a m e n t adopted as governmental p o l i c y t h a t the t o t a l energy consumption i n our c o u n t r y would not be a l l o w e d t o i n c r e a s e by an average more than 2% p e r annum u n t i l 1985. Towards the end o f t h i s c e n t u r y zero-growth i s f o r e s e e n . T h i s p o l i c y i s s u b j e c t t o ree v a l u a t i o n i n t h e P a r l i a m e n t i n 1978. However, i t i s e x p e c t e d t h a t t h e energy consumption o f t h e i n d u s t r y would be a l l o w e d t o i n c r e a s e by up t o 6% per annum b a l a n c e d by an i n c r e a s e o f l e s s than 2% on t h e p a r t o f other users. The energy c o s t c o n t r i b u t e s o n l y 6% t o t h e s a l e s v a l u e o f the p r o d u c t s ; s t i l l t h e t o t a l energy consumption i s about 40% o f t h a t f o r the i n d u s t r y as a whole. On t h e o t h e r hand p u l p and paper makers a l s o produce l a r g e amounts o f energy e s p e c i a l l y through t h e b u r n i n g o f waste l i q u o r s from d i g e s t e r s . About h a l f of t h e steam r e q u i r e d and one t h i r d o f the e l e c t r i c power needed i s g e n e r a t e d w i t h i n t h e p l a n t s . The end r e s u l t i s t h a t about 20% o f t h e energy consumed must be bought from o u t s i d e s o u r c e s . T h i s s t i l l b r i n g s t h e p u l p and paper i n d u s t r y t o g e t h e r w i t h t h e s t e e l i n d u s t r y i n t o t h e top p o s i t i o n as energy consumers. Both i n d u s t r i e s a r e t h e r e f o r e under p r e s s u r e from t h e Government t o do whatever i s p o s s i b l e to d e c r e a s e t h e i r energy consumption. Our b r a n c h o r g a n i z a t i o n , t h e Swedish P u l p and Paper M a n u f a c t u r e r s A s s o c i a t i o n ( c o r r e s p o n d i n g approxi m a t e l y t o t h e American Paper I n s t i t u t e ) has an a c t i v e energy committee working on problems o f mutual i n t e r e s t and has a l s o got some funds from t h e i n d u s t r y at t h e i r d i s p o s a l f o r R and D. The Government on i t s s i d e i s now r e l e a s i n g c o n s i d e r a b l e funds f o r R and D on energy problems and has i n d i c a t e d t h a t t h e p u l p and paper i n d u s t r y w i l l be i n a f a v o u r e d p o s i t i o n t o r e c e i v e
9.
JULLANDER
Swedish Pulp and Paper Industry
191
g r a n t s f o r c o l l e c t i v e r e s e a r c h i n the energy a r e a . As p r e v i o u s l y mentioned, our i n d u s t r y i s a l r e a d y w e l l r a t i o n a l i z e d i n energy m a t t e r s and no r e v o l u t i o n a r y s a v i n g s are l i k e l y to o c c u r . R a t h e r , a l a r g e number o f s m a l l improvements w i l l be p o s s i b l e . One i n t e r e s t i n g study has been made by the Swedish Steam U s e r ' s A s s o c i a t i o n c o n t r a c t e d by t h e branch o r g a n i z a t i o n . For a number o f p l a n t s , the minimum energy consumption has been c a l c u l a t e d f o r each l i n k i n the p r o c e s s i n g c h a i n , assuming t h a t the b e s t t e c h n i q u e a v a i l a b l e t o day i s used throughout the p l a n t . On the energy p r o d u c t i o n s i d e the use o f b a r k t o r e p l a c e p a r t o f the o i l i n steam p r o d u c t i o n i s i n c r e a s i n g r a p i d l y . From the n a t i o n a l economy p o i n t o f view the d e s i r a b i l i t y o f an i n c r e a s e d p r o d u c t i o n o f e l e c t r i c a l b a c k - p r e s s u r e power i s c l e a r l y seen. The p r a c t i c a l r e a l i z a t i o n has t u r n e d out t o be a very comp l i c a t e d problem where the whole p r i c e s t r u c t u r e o f e l e c t r i c power i n Sweden must be taken i n t o c o n s i d e r a tion . E n v i r o n m e n t a l Problems. A few y e a r s ago i t became apparent t h a t the Swedish p u l p and paper i n d u s t r y had t o make v e r y b i g investments i n equipment and p r o c e s s e s changes f o r water and a i r p o l l u t i o n a b a t e ment. The Swedish P u l p and Paper M a n u f a c t u r e r s A s s o c i a t i o n t h e r e f o r e took t h e i n i t i a t i v e i n s t a r t i n g an e x t e n s i v e , j o i n t r e s e a r c h p r o j e c t , the SSVL e n v i r o n mental care p r o j e c t . This consisted f i r s t l y of a survey o f the b e s t a v a i l a b l e t e c h n i q u e s , and s e c o n d l y o f a number o f r e s e a r c h and development p r o j e c t s d e s i g n e d t o s e r v e as a g u i d e f o r investment i n e n v i r o n m e n t a l care. The SSVL p r o j e c t was c a r r i e d out between 1970 and 1973 w i t h a t o t a l budget o f about 7 m i l l i o n US dollars. (SSVL - a b b r e v i a t i o n i n Swedish o f F o r e s t I n d u s t r i e s ' Water and A i r P o l l u t i o n Research Foundation.) The SSVL p r o j e c t was d i v i d e d i n t o e i g h t s u b p r o j ects. I s h a l l say a few words about two o f them: the a c c i d e n t a l d i s c h a r g e s and the c l o s u r e o f the water systems i n paper m i l l s . A c c i d e n t a l D i s c h a r g e s . A c c o r d i n g t o the d a t a c o l l e c t e d , a c c i d e n t a l temporary d i s c h a r g e s account f o r between 20 and 50% o f the t o t a l d i s c h a r g e o f c h e m i c a l s by the p u l p m i l l s ( e x c l u d i n g the b l e a c h i n g p l a n t s ) and
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f o r between 30 and 50% o f the d i s c h a r g e o f f i b r e s . They can be d i v i d e d i n t o t h r e e main groups a c c o r d i n g t o t h e i r cause: f a i l u r e o f apparatus ( f o r example, t h e t e a r i n g o f a f i l t e r c l o t h ) ; t h e human f a c t o r ( f o r example, a f o r g o t t e n v a l v e ) ; r e g u l a t o r e r r o r s ( f o r example, o v e r f l o w due t o p r o c e s s departments b e i n g out o f p h a s e ) . Temporary d i s c h a r g e s a r e o f t e n o f s h o r t d u r a t i o n (about 10 m i n u t e s ) . E x t r e m e l y b r i e f d i s c h a r g e s can t h e r e f o r e be d i s c o v e r e d o n l y by c o n t i n u o u s measurement and s u p e r v i s i o n o f the e f f l u e n t s or by v e r y f r e q u e n t sampling. The sodium c o n t e n t i n t h e e f f l u e n t from a k r a f t m i l l was d e t e r m i n e d i n samples taken a t 15 minu t e i n t e r v a l s over a three-month p e r i o d . Very l a r g e v a r i a t i o n s were found even between two s u c c e s s i v e samples. The c l o s e r the measurements a r e made t o the s o u r c e o f the d i s c h a r g e the g r e a t e r w i l l be the d i f f e r ence between temporary and c o n t i n u o u s d i s c h a r g e s , and the e a s i e r i t w i l l be to d e t e r m i n e what p r o p o r t i o n t h e former c o n s t i t u t e o f t h e t o t a l . From v a l u e s o b t a i n e d , i t can be e s t i m a t e d t h a t the temporary d i s c h a r g e s a r e r e s p o n s i b l e f o r an a n n u a l l o s s amounting t o 80,000 t per year o f f i b r e s i n t h e Swedish p u l p i n d u s t r y and t o 100,000 t o f N a S 0 p e r year i n k r a f t m i l l s . Temporary and a c c i d e n t a l d i s c h a r g e s t h e r e f o r e cons t i t u t e an important i t e m f o r c o n s i d e r a t i o n when a company i n t e n d s t o i n v e s t money i n measures to r e d u c e pollution. T h i s i s an a r e a where economic and environmental i n t e r e s t s c o i n c i d e . C l o s i n g Paper M i l l s . The mean water consumption and f i b r e l o s s i n Swedish paper m i l l s i n 1971, and a t h e o r e t i c a l s i t u a t i o n assuming t h e b e s t t e c h n o l o g y a v a i l a b l e i n 1973 -- t h a t i s t o say, what c o u l d be a c h i e v e d through the g e n e r a l a p p l i c a t i o n o f e x i s t i n g knowledge and equipment — were c o n s i d e r e d . This i s , o f c o u r s e , not e c o n o m i c a l l y f e a s i b l e i n t h e c a s e o f o l d e r machines s i n c e i t would n e c e s s i t a t e r a d i c a l modifications. I t i s always a g o a l towards which t h e i n d u s t r y can aim and -- no doubt -- a l s o a g o a l t o wards which the o f f i c a l a u t h o r i t i e s want us t o work. What i s shown h e r e i s a t h e o r e t i c a l g o a l as seen i n 1973. Where we a r e a c t u a l l y today i s j u s t now b e i n g evaluated. 2
4
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We have d e f i n i t e e v i d e n c e how the water p o l l u t i o n s i t u a t i o n i n Sweden i s i m p r o v i n g . The t o t a l BOD l o a d i s d e c r e a s i n g at an a c c e l e r a t e d r a t e but t h e p u l p and paper i n d u s t r y i s s t i l l t h e d o m i n a t i n g p o l l u t a n t as f a r as BOD i s c o n c e r n e d . I f the v a l u e s from 1972 are e x t r a p o l a t e d , t h e improvement i s c l o s e l y f o l l o w i n g the p r e d i c t i o n , i n f a c t we a r e at the moment l y i n g a t r i f l e below the p r o g n o s i s . The d i f f e r e n c e i s h a r d l y s t a t i s t i c a l l y s i g n i f i c a n t , though. The q u a l i t y o f the water i n our l a r g e s t l a k e , Vanern ( t h e s u r f a c e i s about one f i f t h o f l a k e E r i e ) has s t e a d i l y d e c r e a s e d s i n c e the b e g i n n i n g o f t h i s c e n t u r y due t o l i g n i n e f f l u e n t from s u r r o u n d i n g p u l p p l a n t s . The s i t u a t i o n i s now d e f i n i t e l y improving. B e f o r e c o n c l u d i n g , I w i l l say a few words about c o l l e c t i v e r e s e a r c h i n Sweden. F i r s t , i t s h o u l d be e x p l a i n e d t h a t we have i n our c o u n t r y no a n t i - t r u s t law o f US t y p e . A l l companies w i t h i n a branch a r e welcome t o j o i n f o r c e s i n R and D and i n programs f o r t e c h n i c a l development g e n e r a l l y s p e a k i n g . Chances a r e good t h a t the Swedish government w i l l a l s o c o n t r i b u t e f i n a n c i a l l y t o such p r o j e c t s . The e x i s t e n c e of t h e Swedish F o r e s t P r o d u c t s Labo r a t o r y i s based on t h i s p o l i c y o f c o o p e r a t i o n between the government and a l l i n d u s t r i e s w i t h i n a b r a n c h . We a r e employing about 330 p e o p l e and have an annual budget c l o s e t o 9 m i l l i o n d o l l a r s . A n o t h e r example o f a j o i n t i n d u s t r i a l u n d e r t a k i n g i s the SSVL p r o j e c t a l r e a d y r e f e r r e d t o . Much o f the r e a l work was done at d i f f e r e n t i n d u s t r i e s and d u r i n g a g r e a t amount o f sub-group meetings where e x p e r t s from d i f f e r e n t p l a n t s met, compared n o t e s from t h e i r own p r a c t i c a l e x p e r i e n c e s , and d i s c u s s e d what c o u l d be done t o improve the e n v i r o n m e n t a l s i t u a t i o n on s p e c i f i c points. The SSVL e n v i r o n m e n t a l c a r e p r o j e c t has been c o n s i d e r e d a s u c c e s s . Today s e v e r a l p r o j e c t s a r e act i v e which a r e more or l e s s modelled a f t e r the SSVL project. I w i l l mention t h r e e o f them. A d i r e c t f o l l o w up o f the SSVL e n v i r o n m e n t a l c a r e p r o j e c t i s N o r d m i l j o 80 (a d i r e c t t r a n s l a t i o n would be N o r t h e r n environment 1980). T h i s i s a j o i n t S c a n d i n a v i a n u n d e r t a k i n g w i t h F i n l a n d , Norway and Sweden as p a r t n e r s and a t o t a l budget o f around 2.5 M d o l l a r s (11 MSw crowns), t o be spent i n t h r e e y e a r s . It i s
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run i n c o o p e r a t i o n w i t h t h e e n v i r o n m e n t a l p r o t e c t i o n a u t h o r i t i e s i n the three c o u n t r i e s . The aim i s t o f i d a p p r o p r i a t e methods f o r e n v i r o n m e n t a l s u p e r v i s i o n w i t h i n t h e p u l p and paper i n d u s t r i e s . The p r e v e n t i o n o f the a c c i d e n t a l d i s c h a r g e s i s one important p o i n t w i t h i n the p r o j e c t . Our f o r e s t r y and f o r e s t p r o d u c t s i n d u s t r i e s have j o i n e d f o r c e s i n t h e PHU-project, i . e . whole t r e e u t i l i z a t i o n p r o j e c t , r u n n i n g f o r t h r e e y e a r s at a t o t a l c o s t o f around 3 M d o l l a r s . The d r i v i n g f o r c e b e h i n d t h i s p r o j e c t i s o f c o u r s e our raw m a t e r i a l supply situation. I t i s n e c e s s a r y t h a t we e v a l u a t e a l l p o s s i b l e ways to i n c r e a s e the use o f the biomass which n a t u r e i s p r o d u c i n g f o r us i n the f o r e s t s . The t h i r d example i s the T-pulp p r o j e c t , s u r v e y i n g the m a n u f a c t u r i n g methods and e s p e c i a l l y uses f o r a l l t y p e s o f paper o f thermomechanical p u l p . It i s a l s o r u n n i n g t h r e e y e a r s and has a t o t a l budget o f s l i g h t l y more than 3 M d o l l a r s . A l l t h e s e p r o j e c t s a r e run w i t h f a i r l y d e t a i l e d and f i x e d time s c h e d u l e s . A l s o , t h r e e y e a r s i s a v e r y s h o r t time t o make something t e c h n i c a l l y v a l u a b l e s t a r t i n g from r e s e a r c h . They a r e t h e r e f o r e no t r u e r e s e a r c h p r o j e c t s i n the r e s t r i c t e d sense o f the word, r a t h e r the emphasis i s on the development s i d e . As an i l l u s t r a t i o n i t can be mentioned t h a t a l t h o u g h t h e Swedish F o r e s t P r o d u c t s Research L a b o r a t o r y i s admini s t r a t i n g t h e T-pulp p r o j e c t , our own r e s e a r c h projects on m e c h a n i c a l p u l p a r e d e l i b e r a t e l y put o u t s i d e the project. Of c o u r s e the r e s u l t s from t h e s e p r o j e c t s a r e c o n t i n u o u s l y put at t h e d i s p o s a l o f t h e T-pulp project. Summing Up. T h i s has perhaps been a too k a l e i d o s c o p i c p r e s e n t a t i o n o f the Swedish f o r e s t p r o d u c t s industry. What l i e s b e f o r e us a r e a l l the d i f f i c u l t and important problems c o n n e c t e d w i t h a c o m p l e t e l y new raw m a t e r i a l s u p p l y s i t u a t i o n . In a d d i t i o n t o t h i s we have t h e never ending demands from t h e e n v i r o n m e n t a l ists. A l l t h i s i s w e l l b a l a n c e d by our f i r m b e l i e f t h a t Western Europe i s a steady and n a t u r a l market f o r our e x p o r t p r o d u c t s a l s o i n the f o r e s e e a b l e f u t u r e .
