DESCRIPTION Techni ca L filed The' raw material of today for the preparation of cellulose for paper production is primarily wood pulp. A number of processes are used. They are characterized most of all of high investment costs and a high energy consumption due to high process tempe¬ ratures with a high working pressure, which results in trouble- some discharges to air, land and water recipients.

As a complement to the more and more decreasing supply of wood raw material other cellulose sources, such as energy forests, grass, straw, leguminous plants etc. been tested. In general one has then used the same production technique as used for wood pulp and thereby obtained the same end results upon the envi ron ent .

The present invention relates to a reduction of the environ- mental problems described as well as energy costs by working with another raw material, running the process at a low tem¬ perature, a low pressure and a small consumption of chemicals.

As cellulose raw materials annual cereals are primarily used, such as wheat, rye, barley, etc. but also rice, corn, reed, grass and leguminous plants.

In the process the whole biomass is used. The whole biomass of for example wheat, rye, barley can be divided into a straw part (the straw with its stem, leaves and husks) and a grain part (the grain with the core ⁾ . The straw part is then present as main raw material for the cellulose recovery. The grain part as a main component for the recovery of a nutrient solution, al¬ ternatively for the fermentation of alcohols. The embodiment of the invention is described in the flow diagram of appendix 1 and 2.

In the description below the nomenclature "cellulose" is used as a collective name for a number of components of the compo¬ sition of the biomass. At the combination of straw and grain for the recovery of cellulose as well as a nutrient solution, and alcohol, alternatively, thus the husk fraction is part of this name. The composition of the raw materials is evident from the appendix 3.

The process is controlled by addition of aLkali, temperature, and reaction time. As alkali known hydroxides of primari ly Na and Ca are used, alone or in combination. In particular Ca(0H) _? has turned out to be favourable at the returning to the farming land. Purification and recovery of Na, respectively can be made in any method known from the cellulose technique. The tempera- ture can be varied within wide limits from 20 C to close to the boiling point, 95 C. The reaction time is dependent on the ad¬ dition of alkali and temperature. The process is controlled and run using known technique from the cellulose industry.

The following notifications are used in the examples given be¬ low : pH is determined e lect rometri ca I ly di rect in a test sample of the slurry at 20 C, Ac is determined as used, and added alkali, respectively. 10 g of filtrated slurry is di luted to about 100 ml and is titrated using 1/10 N HCl to pH 8.5 (phenoIphta le- ine) . The amount of 1/10N HCl used is = acidity. rTS is detei— mined refracto et r ca I ly using a ABBE refract romete r for the sugar industry., Brix is connected to refraction index and gives directly %TS (dry matter contents) in a sugar solution.

The raw material consists of field harvested crop whole biomass of wheat consisting of 50 % by weight of straw mass and 50 % by weight of grain mass. The variation is normally + _^ 10%. In order to obtain internally reproducible laboratory samples field har¬ vested biomass has been threshed and fractionated in a pure straw part and a pure grain part. The fractions are then used together in the weight relationship 50:50. Grinding of the

fractions has been made on a hammer mill using 2 mm sieve ope¬ nings .

Embodiment examples. Examp le 1.

Relates to the processing of the whole biomass to cellulose part (solid part), and nutrient solution (liquid part) compris¬ ing the straw as well as the insoluble nutrients of the grain part which have been converted enzymat ca I ly to soluble com- pounds such as glucose, proteins and salts. Flow diagram in ap¬ pendixes 1 and 2.

Process: 300 g of biomass (150 g of straw and 150 g of grain part) are ground into 3000 g of water. The pH of the slurry is adjusted to pH about 7 using calcium hydroxide solution. Then ft 0.25 g of a Ifa-amy lase , Termamyl , 0.25 g of a protease, Neut- rase , and 0.5 g of a combination enzyme SP 342 comprising cel- lulase, gluconase, hemicellulae and protease are added. All the enzymes are manufactured by N0V0, Copenhagen, DK. The slurry is heated to 50 C for 2 hrs. The temperature is raised to 95°C for 1 hr and is then cooled to 65 C. pH is adjusted to about 4.5 using 4 g of phosphoric acid. Then 0.4 g of amy log luc os i dase (N0V0) are added. The solution is being completely saccharified for 16 hrs, whereupon -the enzymes present are inactivated by raising the temperature to 95 C. The slurry is cooled and is separated into one solid and one liquid phase in a screen cent¬ rifuge. The solid phase, the fibres, are washed with water. Yield 2,200 g of liquid phase having a 5% DS and 2,200 g of washing solution having a 0.3% DS (return solution for the next production cycle) . Yield of syrup: 2,200 g x 5,3 DS. Yield of fibres: 580 g of moist material from the straw and grain parts, which is fed to the ce I lu Lose /paperp roduct i on . The amount of fibre obtained, 580 g, is fed into 2,200 g of water and 40 g of Ca(0H) . Analysis of the process liquid: rTS = 1,0, pH = 12.1, Ac = 24. The slurry is kept at 90-95°C for about 6 hrs, the a stabi lization of the pH and Ac have been obtained. The slurry is adjusted to the original 3,170 g. Analysis: rTS = 1.6, pH = 11.7, Ac = 9.5. Solid and liquid phases are separated in a

screen centrifuge. The fibres are washed using water, and the wash water is returned to a new cycle together with the process liquid having been separated off. The a I ka I i -fibres having been washed are ground using 2 I of water, are neutralized to pH 6.5 ^• * using phosphoric acid. The slurry is diluted to 5 I. The pulp is drawn off on a wi re cloth and is washed. The cake is dried for 12 hrs at 75°C. Yield: 126 g DS paper pulp. To obtain a higher end concentration of the nutrient solution (5.0% DS) the amount of biomass 300 g can be complemented with a further 150

10 g of wheat grain only. Hereby an increase of of about 10% nut¬ rient solution is obtained. To another 150 g of wheat grains, i .e. to a total of 450 g of wheat grains, an about 15% nutrient solution is obtained simultaneously as the yield of cellulose increases due to the husk fraction of the wheat grains. 15

Example 2.

Relates to processing of the whole biomass to paper and alco¬ hol.

Flow diagram appendixes 1 and 2. ² " Process: 300 g of biomass (150 g of straw part, and 150 g of grain part) are fed into 3000 g of water, pH is adjusted to about 7 using some calcium hydroxide solution. Subsequently

0.25 g of a Ifa-amylase, Termamyl , and 0.25 g of protease, p -.

Neutrase , were added. The slurry was heated to 50 C for 0.5 ²⁵ hrs. Then the temperature was raised to 95°C for 1 hr. The slurry was then cooled to 65 C and the slurry was adjusted to 3.300 g, and pH was lowered to 4.5 using 4 g of phosphoric acid, whereupon 0.5 g of amy log lucosi dase , N0V0, were added. Complete sacchaπ ^* f i cat on of the sugar part for 16 hrs, where- ™ upon the enzymes were deactivated at 95 C for 0.5 hrs. The slurry was cooled to 35 C and fermented at 35°C for 18 hrs _, when the release of CO- ceased. From the mash thus obtained 500 g of a disti llate containing 10.3% ethanol was disti lled off, which gives 51.5 g of 100 % ethanol. The slurry remaining in the fer- ³⁵ mentation and disti llation column was di luted to 3.300 g. Solid and liquid phases were separated using a screen centrifuge. The fibres were washed using 300 g of water. Yield: 602 g of moist

fibres. These fibres were fed down into 2000 g of water + 15 g of NaOH. The analysis of the process liquid: rTS = 1.4, pH = 11.9; Ac = 21. The slurry was kept at 20 to 22°C for 12 hrs when a stabilization had been obtained. Analysis of the slurry: rTS = 2.5; pH = 11.4; Ac = 6.6. Solid and liquid phases were separated in a screen centrifuge. The fibres were washed using 300 g of water. Yield: Wet fibres 600 g = 128 g DS in the form of paper pulp, which consists of two cellulose components, the composition of which is evident from appendix 3, Raw materials. The process liquid and the wash water are returned to a new cy¬ cle .

In order to determine the contribution of the single components in the yield of alcohol, and cellulose-paper, respectively, of the end product a separate processing of wheat grains only, and straw only, respectively been made according to the following. Example A

150 g of wheat grains only were processed in accordance with Example 2 above and were fermented whereby 43.9 g of 100 % eth- anol were obtained. The remaining slurry was screened and the husk fraction was washed, dried for 12 hrs at 75°C, which gave 14 g DS. The dried husks were soaked into 200 g of water and were processed to paper in accordance with Example 2. Yield: 10 g of cellulose.

Example B

150 g of straw only, were processed in accordance with Example 2 above, whereby 7.4 g of 100 % ethanol were obtained. The re¬ maining slurry of straw was separated off, washed, and subse- quently processed to paper, whereby 116 g of cellulose were ob¬ tained .

In total: Alcohol: 43.9 + 7.4 = 51.3 g Cellulose: 10 + 116 = 126 g

E x a mp l e 3 . "

Relates to comparative processing of whole biomass to paper and alcohol, where the combination enzyme SP 342 is present. 300 g of biomass are fed into 3000 g of water, pH is adjusted to about 7 using some calcium hydroxide solution. Then 0.25 g of

R R a Ifa-amylase, Termamyl , 0.25 g of a protease, Neutrase , and

0.5 g of SP 342 comprising cellulase, hem i ce 11 u lase , gluconase, and protease are added. The slurry is heated to 50 C for 2 hrs, whereupon the temperature is raised to 95 C for 1 hr and is then cooled to 65°C. The weight is adjusted to 3,300 g and pH is adjusted to 4.5 using 4 g of phosphoric acid. Then 0.4 g of amylog lucos i dase are added and complete sac chari fi cati on took place for 16 hrs. The slurry contained 3,177 g having a rTS = 5.2. The slurry was cooled to 35 C, bakery yeast was added and fermentation took place for 18 hrs when the release of CO- ceased. From the mash 500 g of an alcoholic solution containing 11.22% by weight of ethanol = 56 g of 100 % ethanol was dis¬ ti lled off. The slurry remaining in the vessel was di luted to 3.000 g and was separated in a screen centrifuge. The fibres were washed, whereby 2500 g of a return solution were obtained for a new cycle, and 574 g of moist fibres. These fibres were fed down into 2000 g of water + 15 g of NaOH. The analysis of the process liquid: rTS = 1.3, pH = 11.8; Ac = 20. The slurry was kept at 20 to 22 C for 12 hrs when a stabilization had been obtained. Analysis of the slurry: rTS = 2.4; pH = 11.4; Ac = 6.5. Solid and liquid phases were separated. The fibres were washed, whereby 565 g of moist fibres and 2300 g of return liq¬ uid were obtained having a rTS = 2.1 for a new cycle. The fi¬ bres were ground with 2000 g of water and were neutralized us- ng 5 g of phosphoric acid to pH 6.5. The slurry was di luted to 5 I and was drained on a wire screen. The cake was washed. The sshheeeett wwaass ddrriieed for 12 hrs at 75 °C Y i e l d : 1 17 g of c e l- lu l o se- paper pulp DS.

Storage test with preserved biomass using Ca(OH)., Test material: Totally harvested cut biomass of ^" wheat (har¬ vested during mild rain) . The amount of calcium oxide powder was calculated on the DS of the biomass.

Test :

The whole biomass consisted of 50% by weight of straw, and 50 % by weight of grain. Water content 31%. 100 g of biomass were placed in tight plastic bags and calcium oxide powder was added and mixed into it as a pulverulent skin. The bags were flatten¬ ed and well closed. 3 samples of each mixture were stored in a dark heating cabinet at the temperatures given.

Mi Idew after Sample Temperature

% CaO 1 months 6 months 12 months

0 20 weak strong very strong

1 none none weak none none none

5 none none none

0 37 weak strong very strong

1 weak strong very strong 2 none none none

5 none none none

Paper sheets produced from pulp according to the Examples above were tested.

Preparation: The fibre pulp was di luted to about 1.75 g pulp

DS/litre of water. So much slurry was used that the final sheet weighed (surface weight) 100- g/m . Draining on the wire screen in a sheet former, pressing, drying and conditioning.

The results of the test are evident from the table below:

Table

Test

Pa rameters 1 2 3 4 5

Surface weight g/m' 100 99 99 98 103 Tens i le index Nm/g 40 39 41 40 41

Ducti le yield % 1.7 1.8 1.2 1.8 2.0

2 Burst index Pam /g 2.1 2.0 2.2 2.1 2.3

2 Opacity (60 g/m ) 99.4 99.2 99.1 99.3 98.3

% Na <0.1 0.60 0.55 1.0 <0.1

% Ca 3.03 0.13 0.15 0.20 <0.1

Test 1 : Nutrient solution + paper with Ca(0H)_ Test 2: Alcohol + paper with NaOH Test 3: Alcohol with SP 342 + paper with NaOH Test 4: Straw only + paper with NaOH

Test 5: Preparation of return paper fibres from wood cellulose from paper mi ll