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Файл:The bases of special methods of biomass processing into prospective materials. Tutorial
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For example, the technology for production of nanocellulose from
sugar production waste – namely, from desugared sugar beet pulp. Raw
materials are annually renewable, abundant in the central regions of Russia
and are little demanded because of low nutritional value. Seasonal nature of
sugar production is not a deterrent because the beet pulp pellets, produced
at the sugar mills, is suitable for year-round storage. Unlike timber, sugar
beet pulp contains almost no lignin – a binding substance, which is difficult
to separate from cellulose fibers. Binder in the sugar beet is pectin, which is
easier to remove from the cellulose fibers, and is itself a valuable food
product. The developed technologies do not use concentrated mineral acids,
expensive enzymes, sulfur and chlorine used in the manufacture of wood
nanocellulose that provides high chemical purity of obtained nanocellulose.
Associated derivation of high-quality pectin ensures the profitability of
production in general. Development of the technology was conducted in an
integrated manner with a comprehensive, collaborative problem solving to
get nanocellulose and pectin, recycling waste and providing closed-cycle
water consumption. The production is designed to meet the increasing
health requirements to ensure microbiological purity of the products.
Applications of nanocellulose:
– production of healthy food;
– raw materials for pharmaceuticals and cosmetics;
– manufacture of paper, cardboard, laminates;
– production of modified hardwood;
– production of coated seeds;
– biodegradable composite materials;
– sensors, “smart” packaging;
– basis for catalysts;
– latex, polymer, paints, varnishes, primers, adhesives;
– aerogels, membranes, sorbents, foam.
3.5. Technology testing
3.5.1. Technology for producing the vitamin meal
Objectives: to conduct experimental studies on the preparation and
determination of properties of vitamin meal.
Materials and reagents: tree verdure of various species.
Equipment:
– testing sieve;
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– scales with an accuracy of 0.1;
– wood meal producing unit.
Procedure.
Prepare vitamin meal in laboratory. Unit diagram for the production
of vitamin meal is shown in fig. 3.4.
Fig. 3.4. Unit diagram for the production of vitamin meal:
1 –separator of tree verdure, 2 – crusher-shredder, 3 – bunker, 4 – back chamber
of the dryer, 5 – drum of the dryer, 6 – front chamber of the dryer, 7 – fan,
8 – issuing hatch, 9 – cyclone-bunker, 10 – batcher, 11 – crusher-grinder for the
milling of dry pine needles into the flour; A – softwood bough, B – fuel;
C – finished product; D – flue gas withdrawal
The production technology is the chopping of tree verdure separated
from the branches on the crusher, high-speed drying in a tumble dryer and
grinding of the dried mass. Feeding of the chopped verdure from the
crusher into a bunker of raw verdure and finished flour into a cylone-bunker
is made in pneumatic conveyor by air flow as well as feeding of the
softwood bough from the bunker to the dryer drum and unloading of the
dried verdure from the dryer is made by the screw. From the cyclonebunker flour is discharged through the batcher. The temperature of the heat
carrier in the dryer is 250–300 0C (400 0C), drying time is about 10 s, the
final moisture content is about 10 %. The drum must be fully filled with the
dryable mass, the mass particles during their stay in the drum should not be
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heated above 60–70 0C and the temperature of the worked-out heat carrier
should be between 75–80 0C. Such drying conditions allow preservation
carotene in the needles as much as possible
Determine the properties of vitamin flour according to standards:
GOST 13797-84 «Vitamin meal of tree verdure. Specifications», GOST
13496.8-72 «Mixed feeds. Methods for determination of crushed particle
size and uncrushed seed content of cultured and wild plants».
Colour test. Carried out visually.
Determination of crushed particle size
A specimen of mixed feed of 100 g is sifted through the sieve set
composed in order to reduce the size of the holes from top to bottom.
Sifting is made on sifter-analyzer for 5 min on two or three sieves of set
depending on the requirements of the standard for this type of mixed feed.
It is acceptable to sift by hand in 110–120 movements per minute with
amplitude of sieve vibration of about 10 cm for 3 min. Nubbles formed
during sieving are kneaded at a slight movement in the sieve and finish
sifted for 2 min. At the end of sifting residue on each sieve is weighed
separately. An allowable rate of loss during sieving should not exceed 1 %.
The final experimental result is the average of the results of two
parallel determinations. Permissible differences between the results of
parallel determinations should not exceed 0.1 % and between the results
obtained in different laboratories should not be above 0.2 %.
3.5.2. Technology of using wood meal in filtering units
Theoretical information. Types of filters using wood meal:
– bulk;
– drum vacuum;
– precoat.
Bulk-type filter is a vertical unit with welded elliptical bottom and lid.
For an altitude of 70–75 % the filter is filled by supporting and filtering
materials. The lower slot manifold, as a rule, is closed by supporting layer
(a layer of washed gravel with a size of 2–5 mm). Next, there is a layer of
filtering material whose properties depend on the purpose of the filter.
Drum vacuum filter with outer filtering surface (fig. 3.5). The
peculiarity of the filter is that a layer of auxiliary filtering material is coated
on the working surface before filtration process. This is so called precoat
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layer (usually diatomaceous earth or wood meal). Depending on the filtered
product and the quality of auxiliary filtering material thickness of the
precoat sediment layer is 25 to 75 mm. The precoat layer is applied as
follows. Suspension of material which forms precoat layer is filtered
through a vacuum filter batchwise, alternating with drying of the formed
layer. This method of applying allows the layer of wood meal to be dense
and not to be compressed in further work. The time of applying filtering
layer is from 0.5 to 2 hours.
Fig. 3.5. Drum vacuum filter
The filtering process in precoat filters (fig.3.6) is carried out through
a macroporous precoat layer formed by filtering material specially
introduced at the beginning of filtration cycle (diatomaceous earth,
cellulose, bentonite, active carbon, wood meal, etc.) with a particle size of
50–70 μm at the surface of solid porous support with a pore size of 100–
150 μm. The particle size of precoat filtering material is less than pore size
of filtering support, but these particles are held on its surface as they
deposited on domes formed between the primary wedged particles and
larger aggregates of precoat material. The structural precoat layer consists
of a large number of small-sized channels which provides obtaining a highquality filtrate.
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Fig. 3.6. The filtering process
Objectives: to conduct experimental studies and determine
parameters of water filtration using wood meal.
Materials and reagents:
– wood meal of various grades and species.
Equipment:
– testing sieve;
– filter unit;
– photoelectric colorimeter type CFC;
– scales with an accuracy of 0.1.
Procedure.
Сarry out the experiments on the filtration using wood meal of
various grades. The scheme of the filter unit is shown in fig. 3.7.
Before the start it is necessary to fill the tank with feed water 1 by
opening valve 29, the primary suspension tank 4 by opening valve 27, the
additional suspension tank 5 opening valve 24.
To prepare the initial suspension add adjuvant filtering material in the
filled tank with primary suspension 4, then turning the compressor 6 on,
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open valve 26 to supply compressed air for mixing of the solution. To
prepare the additional suspension add a portion of the powder additives to
the tank of additional suspension, and then turning the compressor 6 on,
open valve 23 also for supplying compressed air for mixing of the solution.
Opening the valve 1, fill the pre-filter with feed water and flood the pumps.
Fig. 3.7. The diagram of unit with the pre-coat filter:
1 – feed water tank; 2 – pre-filter; 3 – pre-coat cartridge filter;
4 – container for preparation primary suspension; 5 – container for additional
suspension preparation; 6 – compressor; 7 – receiver; 8 – circulating pump;
9 – metering pump.
Pipelines: B1 – utility and drinking water supply; B4 – supply of water for
cleaning; B5 – return of water in the bowl of feed water;
B11 – adding a suspension; K1 – domestic sewage; A – compressed air
To run the pumps for the filtering layer aggradation close valve 16,
open valves 13, 14, 15 and the valve of suspension return in the tank of
primary suspension 17. Turn the pumps on and keep up the pressure of 0.6
Mpa. The layer aggradation lasts 15–20 min and monitored visually, that is
clarification of water in the primary suspension tank. Close valves 17, 20
and open valves 5, 16. The water level in prefilter should be regulated by a
gate valve 1. During filtration, the additional suspension entry is necessary
to increase the filter-cycle value, for that open valves 30, 31 and turn a
metering pump on. For aggradation of primary filtering layer prepare a
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suspension with the use of water and powdered filtering material (wood
Wood
meal
species
Amount
of wood
meal
Filtering
rate
Pressure
drop
Feed
water
quality
Filtrate
quality
meal). Aggradation continues till full clarification of water returned from
the filter into the tank of the primary suspension preparation. The initial
flow of powder for creation of filtering layer with thickness of 1–2 mm was
400–600 g per 1 m2 of filtering surface. The duration of aggradation is 15–
25 min, depending on the powder type and suspension concentration. Then
water begins the flow for filtration process. At the same time the additional
suspension of the powder prepared in a different tank is added to water in
small portions. That reduces the growth rate of hydraulic resistance of the
filtering layer and increases the duration of filtration cycle. To increase the
filter-cycle duration the filtering powder in an amount of 3–10 g/m3 is
continuously dosed in the purified water.
To determine the following values during the experiments: filtering
rate on the pre-coat filters, pressure drop across the filtering layer and
quality of the feed water and filtrate. The filtrate quality is determined by
the photometric method with the use of photoelectric colorimeter type CFC.
During the experiments at regular time intervals water (feed and filtered) is
sampled and the turbidity of each sample is determined. The experiment
becomes complete with deterioration in the quality of filtrate.
Present the results of the research in the form of the table:
97
LITERATURE
1. Khudyakov, V.A. Modern composite building materials /
V.A. Khudyakov. – M .: Publishing office Phoenix, 2007. – 220 p.
2. Volynsky, V.N. Technology of wood boards and composite
materials / V.N. Volynsky – SPb. : Lan publishing office, 2009. – 336 p.
3. Belov, V.V. Laboratory definitions of properties of building
materials / V.V. Belov, V.B. Petropavlovskaya, Yu.A. Shlapakov – M. :
Publishing office ASB, 2008. – 200 p.
4. Bolobova, A.V. Theoretical Foundations of Biotechnology of Wood
Composites: Enzymes, models, processes / A. V. Bolobova,
A. A. Askadsky, V. I. Kondrashenko, M. L. Rabinovich - M. : Nauka, 2002. –
343 p.
5. Batayev, A.A. Composite materials: structure, production,
application / А.А. Bataev – M. : Logos Publishing office, 2006. – 398 p.
6. Yudina, N.A. Integrated processing and use of wood waste /
N.A. Yudina // Siberian State Tehnological University. – Krasnoyarsk,
2011. – 60 p.
7. Syunev, V.S. Energy use of woody biomass: harvesting,
transportation, processing and burning: textbook / V.S. Syunev,
A.V. Pitukhin, S.B. Vasiliev // Publishing office of Petrozavodsk State
University, 2014. – 124 p.
CONTENT
INTRODUCTION ....................................................................................... 3
1. GENERAL DATA ON SPECIAL METHODS OF BIOMASS
PROCESSING ............................................................................................ 4
1.1. The concept of biomass ........................................................................ 4
1.2. Classification of wood composite materials (WCM) ......................... 5
1.3. Wood composite material (WCM) molding process classification ...... 7
1.4. Technology of advanced biomass processing. Classification ............. 11
1.5. Technology testing «Technology for producing composite
materials based on wood particles and cement» ........................................ 11
2. TECHNOLOGY OF COMPOSITE MATERIALS
MANUFACTURE .................................................................................... 15
2.1. Technologies for obtaining the composite materials based
on mineral binding agent ........................................................................... 15
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2.2. Technologies for obtaining the composite materials based
on natural binding agents ........................................................................... 30
2.3. Wood modification ............................................................................. 32
2.4. Technology for obtaining the wood-polymeric composites ............... 34
2.4.1. WPC classification .......................................................................... 34
2.4.2. WPC content on the basis of thermoplastics ................................... 37
2.4.3. Manufacturing techniques ............................................................... 39
2.4.4. Fields of application ........................................................................ 42
2.5. Technology testing. ............................................................................ 43
2.5.1. Technology for producing the composite materials based
on wood particles and gypsum .................................................................. 43
2.5.2. Technology for producing the composite materials based
on wood particles and Sorel cement .......................................................... 46
2.5.3. Technology for producing bio-composite materials with
natural binding agents ................................................................................ 50
2.5.4. Technology for producing the wood-polymer composite
(WPCs) preparation by extrusion .............................................................. 54
2.5.5. Technology for producing the wood-polymer composite
preparation by casting process ................................................................... 59
2.5.6. Technology for producing the wood-polymer composite
(WPCs) preparation by flat pressing .......................................................... 65
2.5.7. Technology of thermo-chemical modification of wood .................. 69
3. TECHNOLOGY OF DEEP PROCESSING OF BIOMASS. ................ 73
3.1. Technology for production and use of wood flour ............................. 73
3.1.1. The main properties of wood flour .................................................. 73
3.1.2. Technology of production................................................................ 74
3.1.3. Fields of application ........................................................................ 75
3.2. Extraction technologies ...................................................................... 81
3.2.1. General information about woody vegetation ................................. 81
3.2.2. Methods of processing wood greens ................................................ 82
3.3. Technologies for production and use of vitamin flour ....................... 86
3.3.1. Production of conifer-vitamin flour ................................................. 86
3.3.2. Fields of application ........................................................................ 88
3.4. Technologies for producing and use of nanocellulose ........................ 89
3.5. Technology testing ............................................................................. 91
3.5.1. Technology for producing the vitamin meal .................................... 91
3.5.2. Technology of using wood meal in filtering units ........................... 93
LITERATURE ........................................................................................... 98
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EDUCATIONAL EDITION
Signed in print 30.11.2018
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Kazan National Research Technological University Press
Offset laboratory of Kazan National Research Technological University
420015, Kazan, Karl Marx street, 68
Aigul R. Shaikhutdinova
Ruslan R. Safin
THE BASES OF SPECIAL METHODS
OF BIOMASS PROCESSING INTO
PROSPECTIVE MATERIALS
Responsible for the issue R.R. Khasanshin
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