• Keine Ergebnisse gefunden

The industrial nature of the process provides for continuous control of the biomass quality

REFERENCES

Beck, D . , Th. K r e u t e r , W . P a u l i , W . S o n n e n k a l b , a n d M. ~ i n g p f e i l . V e r f a h r e n z u r Gewinnung p r o t e i n h a l t i g e r F u t t e r m i t t e l a u s B e l e b t s c h l a m m . WP A 23 K/208 5 5 3

Documents o n S i n g l e C e l l P r o t e i n i s s u e d b y PAG. 1 9 7 6 . PAG

G u i d e l i n e N o . 1 5 o n N u t r i t i o n a l a n d S a f e t y A s p e c t s o f N o v e l P r o t e i n S o u r c e s f o r A n i m a l F e e d i n g . March.

H a d e b a l l , W . , I . RUhlemann, S. P b r s c h m a n n , P. S c h e i b e , H . - J . H e i n r i t z , a n d M. R i n g p f e i l . V e r f a h r e n z u r Gewinnung v o n B i o m a s s e a u s G U l l e . WP C 12 D/214 1 6 3

IUPAC. 1 9 7 8 . T e c h n i c a l R e p o r t , F i n a l D r a f t . J u n e . IUPAC. 1979. T e c h n i c a l R e p o r t N r . 1 2 . A u g u s t .

R i n g p f e i l , M . , D . B e c k , W. H a d e b a l l , Th. K r e u t e r , a n d H . - J .

H e i n r i t z . 1 9 8 0 . P r o d u c t i o n o f SCP f r o m W a s t e s i n L i v e s t o c k F a r m i n g . V I . G I A M C o n f e r e n c e , L a g o s , 1 9 8 0 .

R i n g p f e i l , M . , W. H a d e b a l l , P. S c h e i b e , Th. K r e u t e r , D . B e c k , a n d K . Karbaum. 1 9 8 0 . A e r o b i c T r e a t m e n t o f Wastes i n Animal F a c t o r i e s a n d P r o d u c t i o n o f P r o t e i n a c e o u s Biomasses. V I .

I n t e r n a t i o n a l T e r n e n t a t i o n Symposium, London, C a n a d a , 1980.

S c h b n b o r n , W. U s e o f Sewage S l u d g e s a s F o d d e r . 1 9 7 5 . IAEA-SM- 1 9 4 / 7 0 1 , p. 579-588.

A SURVEY OF THE LATEST TECHNOLOGIES

OF FOOD PRODUCTION FROM BY-PRODUCTS

AND WASTES Bohuslav Vencl

E x i s t i n g p r o j e c t i o n s on w o r l d p o p u l a t i o n and food s u p p l y s u g g e s t t h a t a n - - i n c r e a s e i n t h e d e f i c i e n c y o f t h e raw m a t e r i a l s c u r r e n t l y u s e d i n c o n c e n t r a t e f e e d s i n s y s t e m s o f a n i m a l p r o d u c t i o n i s l i k e l y t o d e v e l o p i n t h e f o r s e e a b l e f u t u r e . T h i s d e f i c i t i s p r o b a b l e b e c a u s e t h e w o r l d p o p u l a t i o n w i l l i n c r e a s e more r a p i d l y t h a n t h e p r o d u c t i o n . . o f food c r o p s . W e h a v e t o t r y t o make up t h i s d e f i c i t by i m p r o v i n g t h e u t i l i z a t i o n o f raw m a t e r i a l s and by u p g r a d i n g o t h e r r e s o u r c e s c u r r e n t l y c o n s i d e r e d u n s u i t a b l e . The r e s i d u e s from c e r e a l s and o t h e r c r o p s , f o r e s t p r o d u c t s and a n i m a l w a s t e s a r e examples o f a l t e r n a t i v e s o u r c e s a v a i l a b l e i n r e l a t i v e l y ample s u p p l y ( B u r t , 1973)

.

By-products and w a s t e m a t e r i a l s may b e d e f i n e d a s s u b s i d i a r y components l e f t o v e r from t h e p r o d u c t i o n o f main p r o d u c t s i n

a g r i c u l t u r e . The u s e o f t h e s e f o r f e e d p r o d u c t i o n , which i s t h e t o p i c o f t h i s a r t i c l e , i s a s a t i s f a c t o r y way o f i n c r e a s i n g f e e d r e s o u r c e s and a d i r e c t method o f s u p p l y i n g f o o d t o t h e human

p o p u l a t i o n . By l i n k i n g w a s t e p r o d u c t s t o methods o f u t i l i z i n g s u b s t a n c e s e n v i r o n m e n t a l p o l l u t i o n c a n a l s o b e r e d u c e d . I t i s u s u a l l y n e c e s s a r y t o improve t h e i r poor q u a l i t y and t r a n s f o r m n u t r i e n t s which c a n b e u t i l i z e d by a n i m a l s f o r f e e d . T h e r e a r e p h y s i c a l , c h e m i c a l and b i o l o g i c a l ways o f a c h i e v i n g t h i s p u r p o s e .

THE PRETREATMENT AND USE OF LIGNOCELLULOSIC MATERIALS

L i g n o c e l l u l o s i c m a t e r i a l s c o n t a i n 70-8C% c a r b o h y d r a t e s ,

m o s t l y i n t h e form o f c e l l w a l l p o l y s a c c h a r i d e s and a r e a p o t e n t i a l s o u r c e of d i e t a r y e n e r g y f o r r u m i n a n t s . The amount o f c e l l u l o s e w a s t e from c r o p p r o d u c t i o n and i n d u s t r i a l p r o c e s s e s i s e s t i m a t e d

t o b e 100 000 m i l . tons/annum by Dyer e t a l . ( 1 975)

.

However,

b e f o r e s u c h c a r b o h y d r a t e s c a n b e e x t e n s i v e l y d i g e s t e d i n t h e rumen

i t i s n e c e s s a r y t o p r e t r e a t t h e s e e s p e c i a l l y woody m a t e r i a l s . T r e a t m e n t s h a v e i n c l u d e d d e l i g n i f y i n g a g e n t s , b a l l m i l l i n g ,

l i q u i d ammonia and sodium h y d r o x i d e , which i n c r e a s e t h e d i g e s t i - b i l i t y o f o r g a n i c m a t t e r i n t h e rumen. The t r e a t m e n t s may b e

g r o u p e d a c c o r d i n g t o Dekker a n d R i c h a r d s ( 1 9 7 3 ) u n d e r two h e a d i n g s : t r e a t m e n t s aimed a t t h e d e g r a d a t i o n o f l i g n i n ( w h i c h i s t h o u g h t t o p r o t e c t p o l y s a c c h a r i d e s from d i g e s t i o n ) and o t h e r t r e a t m e n t s which c h a n g e t h e c r y s t a l s t r u c t u r e o f c e l l u l o s e , t h u s i n c r e a s i n g

i t s s w e l l i n g c a p a c i t y i n ag_ueous s o l u t i o n s and p r o v i d i n g g r e a t e r a c c e s s i b i l i t y t o t h e rumen m i c r o o r g a n i s m s a n d t h e i r a s s o c i a t e d enzymes.

The C o n d i t i o n i n g a n d U s e o f L i g n o c e l l u l o s e from t h e P r o c e s s i n g o f Wood M a t t e r

Wood matter c o n s t i t u t e s t h e r i c h e s t s o u r c e o f l i g n o c e l l u l o s e . 70-75% o f t h e volume o f wood i s composed o f p o l y s a c c h a r i d e s . A s s e e n from F A 0 d a t a , 1 , 3 5 0 m i l l i o n t o n s o f wood r e p r e s e n t e d t h e t o t a l w o r l d wood o u t p u t i n 1962. Twenty p e r c e n t o f t h i s amount i s w a s t e . The p o l y s a c c h a r i d e s o f wood a r e bound w i t h l i g n i n . I f t h e d i g e s t i b i l i t y o f l i g n o c e l l u l o s e m a t e r i a l s i s t o b e i n c r e a s e d and t h e m a t e r i a l s a r e t o b e u s e d i n a n i m a l n u t r i t i o n , t h e l i g n i n - s a c c h a r i d e bond, p a r t i c u l a r l y t h e s t r u c t u r a l p o l y s a c c h a r i d e s o f c e l l w a l l s , must b e d e s t r o y e d by a l k a l i n e o r a c i d h y d r o l y s i s o r by m i c r o b i a l c e l l u l a s e s .

The c h e m i c a l .compos-ition . o f . wood. and . s t r a w (

Z)

s p r u c e b e e c h s t r a w s a w d u s t s a w d u s t

l i g n i n c e l l u l o s e h e m i c e l l u l o s e p e n t o s a n s

a s h 1 2 6

n i t r o g e n 0.1 0 . 1 5 0 . 3

e x t r a c t i v e s u b s t a n c e s 2 3 1 . 5

The d i g e s t i b i l i t y o f d i f f e r e n t l i g n o c e l l u l o s i c m a t e r i a l s ( % )

I t i s t h o u g h t t h a t a r e d u c t i o n by a t h i r d o f t h e l i g n i n c o n t e n t

The i n c r e a s e d p r o d u c t i o n o f s y n t h e t i c e t h a n o l s t i m u l a t e s

the NaOH spray treatment process. temperature of 6 2 ' ~ and a 4-day incubation period (Waagepetersen Thomsen, 1977). In Europe, 8 weeks and a rate of 3.5 kg NH3/100 kg.

w i t h Fomes l i v i d u s on o a k sapwood, and o r g a n i c m a t t e r d i g e s t i b i l i t y

THE PROCESSING OF OTHER AGRICULTURAL AIJD FOOD WASTES

acid, 20 mg nicotinic acid and 100 mg choline (Vavak, Fischerova,

h e a l t h problems have r e s u l t e d from f e e d i n g b r o i l e r l i t t e r , t h e r e i s t h e d a n g e r of p a t h o g e n i c o r g a n i s m s i n t h e l i t t e r . F o n t e n o t e t a l . ( 1 9 7 1 ) r e p o r t e d t h a t d r y h e a t was e f f e c t i v e i n d e s t r o y i n g b a c t e r i a p r e s e n t i n b r o i l e r l i t t e r . But a n a t u r a l means o f

d e s t r o y i n g m i c r o o r g a n i s m s , s u c h a s e n s i l i n g l i t t e r w i t h h i g h g r a i n c o r n f o r a g e , would b e more e c o n o m i c a l t h a n t h e u s e o f a r t i f i c i a l h e a t . Lower c o l i f o r m numbers i n l i t t e r s i l a g e s t h a n i n c o n t r o l s s u g g e s t t h a t e n s i l i n g may be a n e c o n o m i c a l means o f e l i m i n a t i n g t h e p o t e n t i a l h a z a r d o f t h e p o s s i b l e p r e s e n c e o f p a t h o g e n s i n t h e l i t t e r (Harmon e t a l . , 1975)

.

P o u l t r y w a s t e p r o d u c t s a r e s i m i l a r t o u r i c a c i d a n d sodium u r a t e b u t s u p e r i o r t o u r e a o r b i u r e t when u s e d a s n i t r o g e n

s u p p l e m e n t s ( a t a l e v e l o f 4 0 % d i e t a r y n i t r o g e n ) f o r b e e f c a t t l e f e d f o r a g e d i e t s ( O l t j e n and D i n i u s , 1 9 7 6 ) .

REFERENCES

B a u e r , S . , V. F a r k a s , I . L a b u d a , a n d N . K o l a r o v a . 1 9 7 9 .

V y u z i v a n i e n e t r a d i c n y c h z d r o j o v b i e l k o v i n a e n e r g i i v o v y z i v e h o s p o d a r s k y c h z v i e r a t . N i t r a .

Beckmann, E. 1 9 2 1 . F e s t s c h r . Kaiser W i l h e l m G e s . F o r d e r u n g W i s s . z e h n j a h r i g e n J u b i l a u m , 18-26.

B u r t . 1 9 7 3 . J S c i . Fd. A g r i c , 2 4 : 4 9 3 - 4 9 7 .

C u t h b e r t , N . H . , W.S. T h i c k e t t , P.N. W i l s o n , a n d T. B r i g s t o c k e . 1 9 7 8 . Anim. P r o d . , 27:161-168.

D e k k e r , R.F.H., a n d G.M. R i c h a r d s . 1 9 7 3 . J . S c i . Fd. A g r i c . , 24:375-379.

D i l w o r t h , B . C . , a n d E . J . Day. 1 9 7 0 . P o u l t r y S c i . 49:1090-1093.

D y e r , I . A . , E. R i q u e i m e , L. B a r i b o , a n d B . Y . Couch. 1 9 7 5 . Wld.

A n i m . R e v . , 1 5 : 3 9 .

F l a m , F. 1 9 6 9 . V e r i f i c a t i o n o f New T e c h n o l o g i c a l P r i n c i p l e s o f t h e M i c r o b i a l P r o d u c t i o n o f P r o t e i n s f r o m S u g a r - B e e t . 11.

Some o f t h e R e s u l t s O b t a i n e d i n O p e r a t i o n T e s t o f t h e

P r o d u c t i o n o f Yeast P r o t e i n s f r o m T h i c k e n e d D i f f u s i o n J u i c e . R e s e a r c h Work, W Z V U h r i n e v e s .

F o n t e n o t , J . P . , K.E. Webb, B.W. Harmon, R.E. T u c k e r , a n d W.E.C.

Moore. 1 9 7 1 . P r o c . I n t e r n a t . Symp. o n L i v e s t o c k Wastes.

A. S . A. E. P u b . , PROC-271:301.

Harmon, B.W., J . P . F o n t e n o t , a n d K.E. Webb. 1 9 7 5 . J . A n i r n . ~ c i . 4 0 : 1 4 4 .

H a r t l e y , R . D . , a n d N . J . K i n g . 1 9 7 3 . J . S c i . F d . A g r i c . , 2 4 : 4 9 6 . Huber, J . T . , R.L. Boman, H.E. H e n d e r s o n . 1 9 7 6 . J . D a i r y S c i .

5 9 : 1 9 3 6 - 1 9 4 3 .

H u d s k y , Z . , a n d J . B a r t o s o v a . 1 9 8 0 . A g r o c h e m i a 2 0 : 1 2 1 - 1 2 3 .

J a c k s o n , M.G. 1 9 7 8 . T r e a t i n g S t r a w f o r A n i m a l P r o d u c t i o n , FAO, R o m e

J a c k s o n , M.G. 1 9 7 7 . A n i m a l F e e d S c i . T e c h o l . 2 : 1 0 5 - 1 3 0 . J a l c , D . , I . Z e l e n a k , a n d J. B u c k o . 1 9 7 9 . I V . S y m p o s i u m ,

V y u z i v a n i e n e t r a d i c n y c h z d r o j o v b i e l k o v i n a e n e r g i i v o v y z i v e h o s p o d a r s k y c h z v i e r a t . N i t r a .

K o s a r , J . , M. P r o k s o v a , a n d R. A p a l o v i c . 1 9 7 5 . R e s . R e p o r t . VUZV U h r i n e v e s .

M i n s o n , D . J . , 1 9 6 3 . J . B r i t , G r a s s . S o c . , 1 8 : 3 9 .

N e d o p i l , F . , a n d M . K o u c k y . 1 9 7 5 . Ziv. v y r o b a , 2 0 : 4 1 3 - 4 2 1 . O l t j e n , R.R., a n d D.A. D i n i u s . 1 9 7 6 . J . Anim. S c i . 4 3 : 2 0 1 . P e t k o v , S . , 0. K a c e r o v s k y , Z . S o v a , I . P a r d u s , a n d I . P a r i z k o v a .

1 9 7 9 . B i o l . c h e m . z i v . v y r o b y . V e t e r i n a r i a , XV:419-428.

R e x e n , I . , a n d V. T h o m e s . 1 9 7 6 . Anim. F e e d ~ c i . T e c h o l . 1 : 7 3 - 8 3 . R y b a r o v a , J . , a n d F . S t r o s . 1 9 7 6 . ~ r m i v a r s t v i , 1 2 : 1 8 6 .

S a n d u l a , J . , L. Masler, a n d K . V i n c e o v a . 1 9 7 9 . I V . S ~ m p o s i u m , V y u z i v a n i e n e t r a d i c n y c h z d r o j o v b i e l k o v i n a e n e r g i i vo

v y z i v e h o s p o d a r s k y c h z v i e r a t . N i t r a .

S i m e c e k , K . 1 9 7 1 . Z i v o c i s n a v y r o b a , 1 6 : 6 3 3 - 6 4 0 . S t r o s , F . , a n d M. R o s a . 1 9 7 6 . K r m i v a r s t v i , 1 1 : 1 8 7 .

S u n d s t l , F . , E. C o m ~ o r t h , a n d P.N. Plowat. 1 9 7 7 . Wld. Anim. R e v . FAO. 2 5 .

V a v a k , J . , a n d J . F i s c h e r o v a . 1 9 7 5 . K r m i v a r s t v i , 1 1 : 2 6 1 - 2 6 3 . V e n c l , B. 1 9 7 7 . R e s . R e p o r t , VUZV U h r i n e v e s .

W a a g e p e t e r s e n , J . , a n d K.V. T h o m e s e n . 1 9 7 7 . Anim. F e e d . S c i . T e c h n o l . , 2 : 1 3 1 - 1 4 2 .

W i l s o n , R.K., and W . J . P i g d e n . 1 9 6 4 . C a n . J . Anim. S c i . , 4 4 : 1 2 2 - 1 2 3 .

ECONOMIC ASPECTS OF THE DEVELOPMENT

OF NEW TECHNOLOGIES

( I n t h e M o n - T r a d i t i o n a l P r o d u c t i o n o f F e e d and F o o d )

Y u r i Khromov

The t i t l e o f t h i s r e p o r t i s t o o c o m p r e h e n s i v e t o g i v e a b r i e f , e x h a u s t i v e c h a r a c t e r i z a t i o n o f t h e p r o b l e m as a w h o l e . T h e r e f o r e , I c h o s e t o c o n c e n t r a t e o n a m e t h o d i c a l a p p r o a c h t o t h e s o l u t i o n o f t h e g i v e n p r o b l e m a n d t h u s i n d i c a t e t h e e c o n o m i c e x p e d i e n c y a n d v a s t p r o s p e c t s o f t h e n o n - t r a d i t i o n a l p r o d u c t i o n o f a g r i c u l t u r a l p r o d u c e and f o o d s t u f f s .

When c o n s i d e r i n g t h e a d v a n t a g e s o f n o n - t r a d i t i o n a l t e c h n o l o g i e s , w e h a v e t o m e n t i o n b r i e f l y t h e c o n s t r a i n t s o f t r a d i t i o n a l p r o d u c t i o n a n d how t h e s e a r e p a r t i a l l y removed i n n o n - t r a d i t i o n a l p r o d u c t i o n .

The r a t e o f w o r l d a g r i c u l t u r a l d e v e l o p m e n t i s n o t a s r a p i d t o d a y a s it w a s 2 0 o r 3 0 y e a r s a g o . The e f f i c i e n c y o f a d d i t i o n a l i n v e s t m e n t s i n a g r i c u l t u r e i s d e c l i n i n g . One n e e d s c o n s i d e r a b l e a m o u n t s o f m i n e r a l r e s o u r c e s , m a c h i n e r y , money a n d l a b o r t o

i n c r e a s e a g r i c u l t u r a l o u t p u t . I n v e s t m e n t s w i l l h a v e t o i n c r e a s e s i x f o l d a n d e n e r g y r e s o u r c e s t h r e e f o l d f o r w o r l d a g r i c u l t u r e t o d o u b l e i t s c r o p y i e l d s . F o r t h e s e y i e l d s t o t r e b l e , it i s

n e c e s s a r y t o i n c r e a s e i n v e s t m e n t s t w e n t y f o l d a n d e n e r g y r e s o u r c e s s i x f o l d . What i s m o r e , t h i s w i l l c a l l f o r a c o n s i d e r a b l e i n c r e a s e i n t h e u s e o f n o n r e n e w a b l e r e s o u r c e s , m a i n l y o i l p r o d u c t s . F o r i n s t a n c e , a t w o f o l d i n c r e a s e i n c r o p y i e l d s i n t h e d e v e l o p i n g c o u n t r i e s w i l l r e q u i r e a n e l e v e n f o l d i n c r e a s e i n t h e p r o d u c t i o n o f f e r t i l i z e r s and s i x f o l d i n c r e a s e i n t h e o u t p u t o f p e s t i c i d e s

( D e n n i s L. Meadows e t a l . 1 9 7 4 . ) The amount o f mined e n e r g y ( f u e l ) s p e n t o n a g r i c u l t u r e i s g r e a t e r t h a n t h e e n e r g y o b t a i n e d i n t h e f o r m o f f o o d . M o r e o v e r , o n e s h o u l d t a k e a c c o u n t o f t h e c o n t i n u o u s g r o w t h o f p r i c e s o f e n e r g y r e s o u r c e s i n t h e w o r l d , a s w e l l a s t h e g r o w i n g demand f o r e n v i r o n m e n t a l p r o t e c t i o n ,

b o t h o f w h i c h w i l l t i g h t e n t h e c o n s t r a i n t s o n f a r m p r o d u c t i o n i n t h e f u t u r e . On t h e w h o l e , n o r m a l a g r i c u l t u r a l d e v e l o p m e n t

r e q u i r e s 6 t o 10 t i m e s more i n v e s t m e n t i n t h e r e l a t e d i n d u s t r i e s

1961-1963 1975 1985 ( f o r e c a s t )

f u n g i , when d r i e d , c o n t a i n 50 t o 75 p e r c e n t o f p r o t e i n . By way of

A n o t h e r n o t e w o r t h y f e a t u r e o f f e e d i n g p r o t e i n i s i t s low

S e c o n d l y , t h e new t e c h n o l o g i e s make i t p o s s i b l e t o lower t h e

of the consumer. Therefore, requirements are made on the new foodstuffs which even many traditional products fail to meet;

the major demand made on the new products is, as a rule, not their better chemical composition, but the traditional physical parameters: 1 ) appearance (color, shape and size) ; 2) familiar taste; 3 ) attractive flavor; 4 texture; 5) temperature;

6 ) quick cooking.

There are a group

of

factors in nsn-traditional protein production whikh ought to be considered by decision-makers.

1. Biochemical types of waste, by-products and end products.

2. Technical feasibility of waste utilization.

3. The availability of wastes and by-products.

4. The economics of the utilization of wastes.

5. The socio-economic aspects of waste utilization.

In order to view the waste problem systematically, one should

not consider it as only a technical, resourcal or economic dilemma.

It is a complex problem. Whether agricultural wastes are utilized or not depends on economic and social constraints in the long run.

1t is often difficult to explain the present form of waste treatment in terms of its profitability.

Among the economic requirements which the new product should meet are as follows:

1) the price of a new product should be the same or lower than that of a traditional product;

2) a new product should be offered where it is advantageous for the buyer, where the consumer has fewer opportunities to buy traditional products;

3) quick and inexpensive to cook;

4 ) the new product should be attractively packaged and this

should be in relation to the price of the product;

5) new products should improve on traditional ones especially where factors such as preservation and storage are better.

In conclusion I would like to stress that in dealing with agricultural wastes, economic considerations are inevitably taken into account. In some cases there is a lot of concern about the treatment or disposal of waste as far as the environment is

affected. In other cases waste utilization means an increase in available resources. Anyhow environmental and resource aspects have an economic background.

REFERENCES

A l l a b y , M. 1 9 7 7 . World Food R e s o u r c e s . A c t u a l a n d P o t e n t i a l . A l t s c h u l , A . , e t a l . e d s . 1 9 7 8 . New P r o t e i n F o o d s . V o l . 3 .

A n i m a l P r o t e i n S u p p l i e s . P a r t A. N e w Y o r k .

C a m p b e l l , K . 1 9 7 9 . Food f o r t h e F u t u r e . U n i v e r s i t y o f N e b r a s k a . C h e r e m i s i n o f f , N . , e t a l . 1 9 8 0 . B i o m a s s . A p p l i c a t i o n s , T e c h n o l o g y

a n d P r o d u c t i o n . New Y o r k .

Duckham, A . , e t a l . e d s . 1 9 7 6 . Food P r o d u c t i o n a n d C o n s u m p t i o n . N e w York.

G i l l a n d , B . 1 9 7 9 . The N e x t S e v e n t y Y e a r s . P o p u l a t i o n , Food a n d R e s o u r c e s . T u n b r i d g e Wells.

J o n e s , A. 1 9 7 9 . World P r o t e i n R e s o u r c e s . L e t c h w o r t h .

L o e h r , R . , e t a l . e d s . 1 9 7 7 . F o o d , F e r t i l i z e r a n d A g r i c u l t u r a l R e s i d u e s . Ann A r b o r .

L o e h r , R . , e t a l . e d s . 1 9 7 9 . B e s t Management P r a c t i c e f o r A g r i c u l t u r e a n d S i l v i c u l t u r e . Ann A r b o r .

Meadows, D . , e t a l . 1 9 7 4 . Dynamics o f Growth i n a F i n i t e W o r l d . C a m b r i d g e , Mass.

M i l n e r , M . , e t a l . e d s . 1 9 7 8 . P r o t e i n R e s o u r c e s a n d T e c h n o l o g y . S t a t u s a n d R e s e a r c h N e e d s . W e s t p o r t .

R e p o r t o n S t r a w U t i l i z a t i o n C o n f e r e n c e . 1 9 7 8 . O x f o r d .

R e s i d u e U t i l i z a t i o n

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Management o f A g r i c u l t u r a l a n d A g r o - I n d u s t r i a l W a s t e s . 1 9 7 7 . UNEP/FAO S e m i n a r P r o c e e d i n g s . Rome.

P i r i e , I?., e d . 1 9 7 5 . Food P r o t e i n R e s o u r c e s . c a m b r i d g e .

T o l s t o g u s o b , V. 1 9 7 9 . N e w Forms o f Food. Moscow. ( i n R u s s i a n )

MODELING THE USE OF AGRICULTURAL WASTE

-

TAKING A BULGARIAN REGION AS AN EXAMPLE M. Albegov, and T. Balabanov

The objectives of this study are as follows:

a) to formulate the core of the problem as it is seen by the authors (with respect to a particular region in Bulgaria) ;

b) to indicate the technical-economic data used in the

calculations and their significance for the conclusions;

C) to show the results of the implementation of the integer program solution and to discuss their stability.

STATEMENT OF THE PROBLEM

Regions with a developed agricultural production and/or food processing industries have substantial cellulose residues such as :

--

crop waste, sugar cane, threshing, crop stubble;

--

animal dung;

--

oil cakes, pressed mud from sugar factories, etc.

At present, these are partially utilized, after intermediate storage, as fertilizer, or burnt or destroyed by some other means, with harmful effects on environmental quality. This in turn

results in additional expenditure. One way of utilizing fully agricultural by-products, and a means of cutting storage ano

processing costs, is transformihg them into.bioqas and sludge (the latter which has great value as a fertilizer) by means of an

established process of anaerobic digestion.

This process is characterized by several factors:

--

the need to collect and transport the residues to the