- DRYING OF SAWN WOOD: WHICH
TECHNOLOGY IS IT BETTER TO USE?
- WHY SHOULD A CUSTOMER CHOOSE
EURODRYERS?
- WHAT
DO "CLIMATIC REPRODUCER UNIT"?
- CHOOSE EURODRYERS: WHICH ARE THE
REAL ADVANTAGES?
- IS IT TRUE THAT ALL EURODRYERS
SYSTEMS EMPLOY MUCH LOWER USED POWER LEVEL THAN OTHER TECHNOLOGICAL TYPES
CURRENTLY ON THE MARKET?
- WHICH ARE SOME OTHER ADVANTAGES OFFERED BY EURODRYERS?
- WHAT IS WOOD DEGRADE?
- HOW CAN EURODRYERS LIMIT WOOD DEGRADE?
- FROZEN
SAWN WOOD: HOW IS IT POSSIBLE TO AVOID DAMAGES WHILE UNFREEZING IN THE
KILN WITH EURODRYERS SYSTEMS?
- IS IT POSSIBLE TO USE EURODRYERS
SYSTEMS WITH COPPA'S TECHNOLOGY AS PRE-DRYERS?
- IS IT POSSIBLE
TO USE EURODRYERS SYSTEMS WITH COPPA'S TECHNOLOGY FOR WOOD
PHYTO SANITARY TREATMENT
- IS IT POSSIBLE TO ADAPT OLD
KILNS FOR NEW DRYERS?
- IS IT POSSIBLE TO DESCRIBE
BRIEFLY A PRE-FABRICATED DRYING KILN AND TUNNEL?
- RELIABILITY OF EURODRYERS
MACHINERY.
- WHAT HAS BEEN WRITTEN IN
THE WORLD ABOUT COPPA'S TECHNOLOGY AND THE RESULTS WE HAVE OBTAINED?
- TECHNICAL ASSISTANCE AND
SPARE PARTS
- IS IT POSSIBLE TO RECEIVE
A PERSONALIZED PROJECT?
- WOOD SHRINKAGE SCHEDULE
- WHERE IS IT POSSIBLE TO SEE
EURODRYERS' PRODUCTION?
DRYING OF SAWN WOOD: WHICH
TECHNOLOGY IS IT BETTER TO USE?
Conventional?
Dehumidification?
Vacuum?
High temperature?
A customer, who needs a dryer for sawn wood, above all requires:
- that wood degrade, or loss of quality and value due to the effect of
drying, is reduced to the minimum;
- the preservation of the colour of the wood and evenness of final humidity;
- low energy consumption;
- the possibility of using electric power with maximum utilization for
example, in low peak periods;
- the possibility of using the processing scraps, when available;
- the possibility of using methane gas;
- the possibility of using systems requiring low energy levels.
Other important requirements are:
- the ability to dry both soft and hard wood efficiently, including
difficult wood such us 80 mm (12/4) oak fresh from saw;
- volume withdrawals in the same percentage as those obtained with perfect
natural drying, that is, roughly 3% less than conventional systems;
- ease of loading and unloading in the cells.
EURODRYERS HAS BEEN PRODUCING SYSTEMS THAT SATISFY THESE
REQUIREMENTS SINCE 1975.
Click here to look at some photographs
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WHY SHOULD A CUSTOMER
CHOOSE EURODRYERS?
Because Eurodryers' systems, avaible in 30 different models
with cycles from 5 to 220 m3 (from 2000 to 85000 Bd.Ft.),
using three different types of technologies which can be
also combined, are substantially speaking, "climatic
reproducer unit", that is they are machines that
can simulate the ideal climate in the kiln and guarantee
drying processes without wood degrade with a difference
of moisture content, between the internal and external side
of the board, lower than 4%, also for difficult species,
such as 80 mm (12/4) oak.
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WHAT DO "CLIMATIC
REPRODUCER UNIT"?
The expression "climatic reproducer unit"
means systems that can simulate the ideal climate in the
kiln, at each stage of the drying process, with the possibility
of stowing in the kiln always the maximum either of soft
or hard wood.
This means that when the electronic regulation is set
correctly, there is no longer risk of setting the wrong
climate causing decay to the wood.
Results: no warping,
ing, collapse, discolouring, etc.
Our systems, in the various drying stages, will create
and maintain perfectly in the kiln, the ideal climate requested
by the electronic instruments, which can also be connected
to a computer.
Our experience shows that a perfect drying operation, especially
for difficult wood such as 80 mm (12/4) oak, does not support
temperature excursions greater or less than 1-2° C (33.8,
35.6° F) from the ideal diagram, does not support humidity
variations and requires, moreover, controlled ventilation.
All our systems guarantee perfect drying processes!
Click here to look at some photographs
But not only that.
By recreating a climate in the cell identical to that required for
natural drying, the volume of withdrawals are more or less the same as
those obtained by a perfect natural drying, that is on average 3% less
than classical conventional systems.
See also the attached table showing the most
important commercial wood species.
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CHOOSE EURODRYERS: WHICH
ARE THE REAL ADVANTAGES?
Our experience of 45 years in the field of drying processing has allowed
us to value any possible situation.
If a customer has only electric power at disposal, he
can opt for our Series T.S.S., with closed circuit heat
pump operation, when outside temperature is less than 16
°C (60.8 ° F), and open circuit heat pump operation
with temperature over 16 °C (60.8 ° F). All adjustments
are made automatically.
If during winter months, the customer uses processing scraps to produce
heat, the T.S.S. Series system can operate only with the hot water or steam
exchanger (like in our Series S.T.S. and T.W.S.), or with heat pump and
the hot water or steam exchanger at the same time.
If the customer has, at low cost, hot water or steam supply all year
round, from processing scraps for example, or from methane gas, the T.W.S
hot water Series or S.T.S. low-pressure steam Series, would be the ideal
systems.
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IS IT TRUE THAT ALL EURODRYERS
SYSTEMS EMPLOY MUCH LOWER USED POWER LEVELS THAN OTHER TECHNOLOGICAL TYPES
CURRENTLY ON THE MARKET?
Yes. It is.
We make an example:
Our 200-220 m3 (85000-94000 Bt.Ft) per cycle systems installed
in Siberia, with outside temperatures below 40 °C (-104.0°
F) in winter, work with just 400.000 Kcal/h (1.588.000 BTU)
used. For the same performance levels, conventional systems
would require 1.200.000 Kcal/h (4.764.000 BTU) approx.
This means that with a 1.200.000 Kcal/h (4.764.000 BTU)
boiler, the customer would power not one but three 200 m3
(85000 Bt.Ft) per cycle Eurodryers systems.
The Kcal/h (BTU) necessary to evaporate 1 Kg (2.205 pounds)
of water from the wood are less than in other systems.
Click here to look at some photographs
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WHICH ARE SOME OTHER ADVANTAGES
OFFERED BY EURODRYERS ?
IMPORTANT:
In conventional systems, if the hot water or steam supply to the
exchangers is cut off - when the boiler is shut down - the drying cycle
stops.
To compensate for this, the doors are opened, as the possible high levels
of humidity would damage the wood, causing mould, discolouring, and so
on. But also in this situation, if the inside temperature is 20/26°
C (68/78.8° F) higher than the outside temperature, the wood will suffer
in the same way.
With Eurodryers' technology there is a valid solution also to solve
situations like this one.
All our system monoblocks are fitted with a stainless steel electric coil,
which will intervene manually or electrically in the event of an emergency.
The drying process continues, more slowly, but without problems
and the doors need not be opened.
Each system, as we have said, has one electronic regulation that can be
connected to a personal computer.
The setting is secure and based on the result of direct experience.
For the customers who prefer not to set the data, we offer a pre-recorded
magnetic card, for each wood essence and thickness that they will specify.
All data on the drying operation can be obtained through the personal
computer, even if located remotely, which will print out the relevant protocols.
From the PC, it is also possible to alter the values set on the electronic
regulation systems.
When necessary, the drying operation can also be controlled manually by
means of the system instruments on the electric panel.
This means that if the electronic regulation is bypassed, the drying
process will in any case continue.
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WHAT IS WOOD DEGRADE?
Degrade is the loss in lumber quality and value due to checks, splits,
warp, discoloration, caused by drying processes, etc. When considering
the costs of drying lumber, capital amortization, electrical and thermic
energy, labour, etc.,
The largest cost-larger than
all the other costs combined-is drying degrade.
In ordinary natural air-drying systems or in numerous artificial drying
systems available on the worldwide market, the average losses in value
due to drying degrade is about 10-13%.
In a perfect drying process, thanks to technologies that can simulate,
at any time, the ideal climate in the kiln, the losses in value can
be limited to less than 2%.
The "climatic reproducer unit" Eurodryers with
Coppa's technology can guarantee this ideal climate.
We make an example:
Essence to dry: European oak green-of-saw (or other essences with the same
features). Thickness: 80 mm (12/4)
Final moisture: 12-16%.
Thanks to our experience, we know that to dry wood without
degrade, kiln temperature must become settled at about 32
°C (89.6° F), with a relative moisture content that
can vary from 95% to 80%. Ventilation among stacks must
be about 1,5 m/sec (1.64 yard). It is important to keep
these conditions as long as the wood reaches the value of
30% (that is under the fibre saturation point). 80 mm oak
(12/4), and all the other wood species particularly difficult
to dry, can't support, in our experience, temperature excursion
greater or less than 1-2°C (33.8-35.6 ° F) from
the ideal diagram. Relative humidity depends on the wood
(indicatively it must change from 90 to 80%).
We have pointed out that conventional dryers can't guarantee the drying
process of difficult wood species with high thickness without degrade and
with a moisture content between the inside and outside part of the board
inferior to 4% .
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HOW CAN EURODRYERS LIMIT
WOOD DEGRADE?
VERY IMPORTANT:
Eurodryers "climatic reproducer unit"
can not only avoid checks, splits, warp, discolorations
etc., but they can also allow to obtain drying processes
with about the same volumetric shrinkages as a perfect natural
air drying (see the attached table).
Example: if we stow in a kiln 200 m3 (85000 Bd.Ft) of sawed wood, at
the end of the drying process, the wood cubic content is about 6m3 (2544
Bd.Ft.) more than in a conventional drying process.
Another example in particular hard conditions.
Siberia, 200 m3 (85000 Bd.Ft.) per cycle kilns, outside
temperature lower than 40°C (-56.0° F), wood species:
40 mm (6/4) pine green-of-saw and frozen, requested final
moisture content: 10-12%.
Drying times with Eurodryers "climatic reproducer
unit ": 8 days, max thermal power used: 400.000 Kcal/h
(1.588.000 BTU), electric power used: 22 Kw.
A corresponding conventional dryer generally requires
max 1.200.000 Kcal/h (4.764.000 BTU) of thermal power and
max 24 Kw of electric power used. So we can deduce that
with Eurodryers systems it is possible to power not only
one but three kilns.
In a cycle of 8 days, it is possible to save 6 m3 (2544
Bt.Ft) of wood in each kiln. The Kcal/h (BTU) necessary
to evaporate 1 kg (2.205 pounds) of water from the wood
are less than in any other systems.
Examples of drying times:
Siberian pine from green-of-saw to final moisture content 10-12%.
Thickness:
25 mm (4/4) = 5/6 days;
38-40 mm 8 (6/4) = 8 days;
50 mm (8/4) = 11-12 days.
European oak, initial moisture: 50-60% about., final moisture:
10-12%.
Thickness:
25 mm (4/4) = 25-32 days;
38 mm (6/4) = 40-50 days;
50 mm (8/4) = 70 days.
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FROZEN SAWN WOOD: HOW
IS IT POSSIBLE TO AVOID DAMAGES WHILE UNFREEZING IN THE KILN WITH EURODRYERS
SYSTEMS?
In the countries where temperature drops below zero degrees centigrade (38.8°
F), down to 50° C (70.0 ° F) like in Siberia,
unfreezing of frozen wood is one important step to prepare
wood for further processing. To avoid possible damages to
sawn wood, our dryers installed in Siberia work with a kiln
temperature of about 26° C (78.8 °F) for hard wood,
and about 30° C (86.0° F) for wood with a relative
humidity of 80-85%.
Also in this phase of wood unfreezing, thanks to Eurodryers and Coppa's
technology, it is possible to avoid wood degrade, consisting in a dark
mark in the middle of the boards and a thin light colour rim all around
this dark mark.
With a right unfreezing process, it is also possible to avoid structural
defects and the risk to cause checks and splits due, as we have said, to
the cyclic wood freezing and unfreezing.
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IS IT POSSIBLE TO USE
EURODRYERS SYSTEMS WITH COPPA'S TECHNOLOGY AS PRE-DRYERS?
Yes, it is. All our systems can be used as pre-dryers.
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IS IT POSSIBLE
TO USE EURODRYERS SYSTEMS WITH COPPA'S TECHNOLOGY FOR WOOD
PHYTO SANITARY TREATMENT
Yes, it is. All our systems can be used for wood phytosanitary
treatment.
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IS IT POSSIBLE TO ADAPT
OLD KILNS FOR NEW DRYERS?
Yes, in many cases, it is possible.
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IS IT POSSIBLE TO DESCRIBE
BRIEFLY A PRE-FABRICATED DRYING KILN AND TUNNEL?
Let's try!
Main-frame
It is composed of standard uprights and modular trusses. The main-frame
is completely built in aluminium alloy to protect it from corrosion phenomena
that take place during drying processes.
Nuts and bolts
Nuts and bolts are in stainless steel.
Supplementary ventilation
Supplementary ventilation is guaranteed by reversible fans placed on a
special truss in aluminium sideways the main air flow.
Air change
The patented Coppa's system for air change is placed in the monobloc
outside the control room.
Roof
The external roofing of the dryer is flat, with a slope of _% just on one
side to ensure roof drainage. Roofing is in pre-painted steel externally,
in stainless steel or pre-painted aluminium internally, with insulation
of k=0,3.
Covering panels
Covering panels are made in pre-painted aluminium alloy. Insulation guarantees
a coefficient of about k=0,25.
Kilns of this type have been installed also in Siberia with
maximum temperature of +36° C (96.8° F) in summer,
lowest temperature of -50 °C (-70.0 ° F) in winter
and temperature in the kiln up to 60°/ 70 °C (140.0
/158.0° F), without problems.
Main-doors
Main-doors can be built with shutters, but they are
usually sliding-doors with hydraulic horizontally sliding
door?, with 80 mm (12/4) panels, the same panels used for
kiln walls, with thermic transmission coefficient K, Kcal/m2
h ° C = 0,25.
Kilns
They can be single, pre-arranged to be combined or combined.
Control room
It is placed next to the kiln and is built with the same material. In this
room are placed machines and electronic controls.
For cold and snowy countries, we have projected a special entrance hall
made to protect the door of the control room from snow obtrusion.
This supplementary kiln structure and the lateral protection of the kiln
settled on special profiles where boards are fixed, are part of our exclusive
technology.
Maximum width of main doors : 13 mt (13.436 yard)
Our kilns and drying units are installed by our specialised technicians
all over the world.
Tunnel dryers
Tunnel dryers, to be placed preferably indoors, are built on a concrete
basement.
Loading takes place with truck on external runners.
They are made of the same material as pre-fabricated kilns.
Loading capacity: from 3 to about 20 m3 (from 1272 to about 8480 Bt.Ft).
They have also a control room where machines and electronic controls are
placed.
Click here to look at some photographs
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RELIABILITY OF EURODRYERS
MACHINERY
The most of our dryers produced and installed since 1975, have been
still working now.
References all over the world demonstrate that what we assert is true.
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WHAT HAS BEEN WRITTEN
IN THE WORLD ABOUT COPPA'S TECHNOLOGY AND THE RESULTS WE HAVE OBTAINED?
Since 1975 onwards, many articles have been written in prestigious magazines
such as Wood Technology, World Wood, Australian Forest
Journal & Logger, Macchine del Legno, Mondo Legno,
where some important customers talk about our drying systems, our technology,
and the results they have obtained with our technology.
We will be pleased to send a copy of these articles to all the people who
require them.
In brief, Eurodryers can offer very high technology
drying machinery, able to obtain low cost drying processes
without wood degrade.
If you are thinking of making a large or small investment,
consult us. We can suggest solutions that are the results
of 45 years of careful experience.
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TECHNICAL ASSISTANCE AND
SPARE PARTS
Eurodryers guarantees the technical training of your workers and
after-sales assistance.
All the spare parts are available in short time for all the drying machinery
sold since 1975.
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IS IT POSSIBLE TO RECEIVE
A PERSONALIZED PROJECT?
Yes, of course!
Click here and you will find a form.
Fill in the form and send it back to us. In a few days, you will receive
a personalised project and a cost estimate.
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WOOD SHRINKAGE SCHEDULE
Shrinkage percentage of wood from green to final moisture content
of 12%
Radial
Tangential Volumetric
| SPECIE |
Natural drying or with patented Coppa's technology |
Artificial drying |
Natural drying or with patented Coppa's technology |
Artificial drying |
Natural drying or with patented Coppa's technology |
Artificial drying |
| Cider |
1.0 |
1.7 |
2.2 |
3.6 |
3.8 |
6.4 |
| Cypress-tree |
2.2 |
3.7 |
3.6 |
6.0 |
5.0 |
9.4 |
| Douglas-Fir |
2.9 |
4.8 |
4.4 |
7.4 |
7.0 |
11.9 |
| Hemlock |
2.5 |
4.5 |
4.5 |
7.5 |
7.0 |
11.8 |
| Pine |
2.2 |
3.7 |
3.8 |
6.3 |
6.5 |
9.6 |
| Spruce |
2.4 |
4.0 |
4.7 |
7.9 |
6.2 |
11.7 |
| Ash |
2.5 |
4.3 |
4.7 |
7.5 |
7.5 |
13.5 |
| Poplar |
2.2 |
3.6 |
4.0 |
6.6 |
8.3 |
11.8 |
| Beech |
3.1 |
5.2 |
6.1 |
10.1 |
11.7 |
17.3 |
| Birch |
3.3 |
5.6 |
4.3 |
7.1 |
10.0 |
14.1 |
| Cherry |
2.4 |
4.0 |
4.3 |
7.1 |
8.6 |
12.7 |
| Elm |
2.6 |
4.4 |
4.7 |
7.8 |
9.4 |
15.2 |
| Maple |
2.2 |
3.6 |
3.6 |
6.0 |
8.2 |
12.4 |
| Oak |
2.2 |
3.6 |
4.0 |
6.7 |
6.9 |
12.0 |
| Walnut |
2.9 |
4.0 |
4.7 |
7.8 |
9.4 |
13.8 |
