METHOD FOR PRODUCTION OF MATERIALS AGGLOMERATED FROM BIOMASS
AND MATERIALS SO PRODUCED
The present invention relates to the method for production of materials agglomerated from biomass and to materials agglomerated from biomas, in the form of flat or moulded boards.
Materials agglomerated from biomass are especially intended for use in a construction industry, mainly for insulation of walls and other structures as well as in a furniture industry.
Agglomerated materials in the form of flat or moulded boards and a method for production of lignocellulose raw materials of plant origin currently known comprise two groups:
-materials and their methods of production in which particles, namely chips and/or technological fibres are manufactured before agglomeration, from lignocellulose wastes, and
-materials and their methods of production in which particles, namely chips and/or technological fibres are manufactured before agglomeration from perennial stems of coniferous and/or leaf trees.
Both methods for production requiring lignocellulose raw material suffer from the same shortcomings: limited and scattered raw material base as well as the need for technologically complicated and laborious processes preparing raw materials for the main production process.
Raw materials of this kind are usually susceptible to weather factors which make it pliant to fungus and bacteria. Majority of affected raw material becomes useless for production.
There is also known from the Polish patent application P-158377, the method for manufacturing boards from wastes involving flax trade, precisely harls. However, the harl products are characterised by some very unpleasant and persistent smell which limits their market applications.
There are known a number of methods for production of composite boards made from agricultural waste material. Unfortunately most of them, are technologically rather problematic. Lets take stems of sugar cane called bogassa which requires an energy-consuming drying process. There are about 95% of moisture contents the moment they leave a sugar plant. The moist bogassa is obviously quickly attacked by fungi and bacteria causing fermentation and decay processes.
All processes requiring wood of old trees share the same disadvantage. Their raw material supply is never stable in respect of quality and form. Moreover, wide scale use of wood causes decrease of land under forests and so has a negative impact on
environment. Another drawback here is a very long growth time, at minimum a few dozens of years and annual productivity from an area unit being less than 2 Mg/ha of wooden matter.
The object of the invention is to eliminate the above-mentioned drawbacks and introduces raw material characterised by fast growing rate and high annual productivity from an area unit.
Method for production of materials agglomerated from biomass, in the form of flat or moulded boards, is characterized in that biomass is produced from stems of a perennial plant called Sida hermaphrodita Rusby and next heteromorphic biomass undergoes homogenizing treatment to particles of average ratio of the largest to the smallest particle being 40 to 80 and particles smaller than 0,25 mm constituting less than 10%.
During homogenizing treatment, it remove some 20-100%, preferably 50% of perenchyma tissue from Sida hermaphrodita Rusby stems.
Homogenous biomass comprising 5-15% of water, is modified by physiochemical treatment with addition of a binder, next it is shaped into sheets or moulded forms and compressed at 0,5-5,0 Mpa, preferably at 1,5- 3,0 Mpa and at 140-220°C, preferably 180°C to obtain intended thickness of the final product during minimum 5 seconds for 1 mm of thickness .
The separated parts of perenchyma tissue are used to produce heat for biomass drying process.
The other object of the invention are the materials agglomerated from biomass which have density from 300 to 900 kg/m3.
The invention and its practical application allows for production of a wide range of composite materials made from the same raw material, that is Sida hermaphrodita Rusby plant. Moreover, the cultivation area, if positioned in the neighbourhood of a plant, may simplify the logistics, transportation and storage issues. This kind of raw material seems to be much better than other currently known and used materials. It is characterised by high productivity, stable quality, low density and easy comminution. It is important that every quantity of this raw material can be added to currently processed materials without any need for modification of technological process.
It is also possible to control the final quality of Sida hermaphrodita Rusby stems by appropriate cultivation such as fertilising and planting density.
The annual productivity of Sida hermaphrodita Rusby amounts to 20 Mg from 1 ha of dry matter. It represents the highest value among the currently used raw materials.
The invention is illustrated by the following practical examples.
Example I .
Biomass obtained by regular chopping up the stems of Sida hermaphrodita Rusby did not undergo further comminution but drying in a high-speed
sizing machine. The binder was added in amount of 12 kg for each 100 kg of dry biomass. Binder consisted of 100 parts by weight of higher water-resistance amino resins containing 65% of dry matter, 4 parts by weight of paraffin emulsion mixed with resin having 55% of dry matter and 1,7 parts by weight of 30% solution of ammonium nitrate. Next there was a sheet formed and initially compressed. Main consolidation took place in a press at 1,5 Mpa pressure and temperature of 180°C. Final thickness and density of the composite material depended on the amount of biomass used in the process. Obtained board was 30 mm thick and 350 kg/m3 dense which made it very well suited for insulation purpouses.
Example 2.
Chopped up stems of Sida hermaphrodita Rusby were further broken up on a 1,5 x 1,5 mm sized mesh screen. Then it was dried and treated with a binder in amount of 12 kg for each 100 kg of dry matter. Binder consisted of 100 parts by weight of higher water-resistance amino resins containing 65% of dry matter, 4 parts by weight of paraffin emulsion mixed with resin having 55% of drymatter and 1,7 parts by weight of 30% solution of ammonium nitrate. Then a three layer sheet was formed so that the outside layers consisted of smaller particles and the inner layer of larger particles. Next the mass was preliminary compressed at 3 Mpa pressure and temperature of 180 °C. The composite material thickness and density depended on the amount of biomass used. The obtained board was 16 mm thick and
680 kg/m3 dense. These parameters make it very suitable for furniture industry and interior fittings .
Materials produced in accordance with the invented method have applications in furniture and construction industries.