Treating process of bamboo

Vertical Soak Diffussion for Bamboo Conservation

 

Environmental

Bamboo Foundation

*Note:
This excellent document is converted from a PDF document

from the www.bamboocentral.org
website.
This was done due to the

PDF causing my PC to hang and space issues.  For the complete and exceptional PDF document please visit there website. No information has been altered. The Environmental Bamboo Foundation (EBF) is an Indonesian non-profit organization started in 1993 by designer and environmentalist, LINDA GARLAND.

The EBF strives to protect tropical forests by promoting and demonstrating the many conservation and development opportunities that bamboo offers. The mission of the Environmental Bamboo Foundation is to encourage, through research and education, the sustainable planting and utilization of bamboo in an effort to promote its many environmental benefits and protect the world's remaining tropical forests and mangroves.

Based in Bali, Indonesia, the EBF has affiliate non-profit organizations in the United States and in Holland.

Acknowledgements

Initial research on modified Boucherie Teatment was done by  Prof. Dr. W. Liese, Universität Hamburg, Germany, and later  adapted by the Environmental  Bamboo Foundation with Don Longuevan under a grant from IESC International Executives Service Corp. Laboratory testing was performed by Koppers-Hickson in New Zealand.

We thank Ben Brown of Mangrove Action Project for providing valuable help and insight during the testing period and providing translation services for the Indonesian edition.

We appreciate the advise/comments made by Prof.Liese along the  development of the VSD treatment.

Many thanks to Emerald Starr of Sacred Mountain Sanctuary in Sideman, Bali, who used a high percentage of experimental VSD treated bamboo timbers when building his resort. Seven years later, the bamboo he used is still in excellent condition.

Research &
Development:
Environmental Bamboo Foundation (EBF)
Graphics & Layout: Studio LaBel, Hedi LaBel
Engineering
Consultant:
Ben Brown
Editorial Assistant: Petra Schneider
Project Manager: Ketut Sadia

 

This publication is not copyrighted. EBF encourages the translation, adaptation and copying of materials for non-commercial use, providing an acknowledgement to EBF.

Every effort has been made to ensure that all the information in this booklet is accurate. However, due to differing conditions, kind and age of the bamboos, tools, and individual skills, the publisher cannot be responsible for any injuries, losses, and other damages that may result from the use of the information of this booklet.

First Edition published 2-1-2003 by: LINDA GARLAND Environmental Bamboo Foundation, Bali, Indonesia, ebf@bamboocentral.info, www.bamboocentral.org

Table of Contents

1. Preface

2. Introduction

3. Managing Bamboo

4. Harvesting Bamboo

4.1The Powderpost Beetle

5. Planning a Treatment Center

5.1 Elevation View

5.2 Floor Pan

6. Tools and Materials

7.  Mixing the Borax Solution

8.  Information about Borates

8.1 Reuse Guidelines

8.2 Disposal Guidelines

8.3 Where to buy BORATES in Indonesia

Preface

The use of bamboo products requires often its protection against biodegradation by chemical treatment. Its application is hindered by the structure of the culm, the need for larger technical installations and the danger of environmental side-effects. The VSD method developed by EBF is obviously an efficient method to obtain well treated culms, safe to be handled. Its wider application, also to other species, will strengthen its base.

Walter Liese Universität Hamburg, Germany

Introduction

Bamboo culms are a natural material susceptible to insect and fungal attack. Without treatment products made from bamboo can be expected to last for only up to 3 years. There are many different techniques for curing and treating bamboo culms in order to prevent splitting, insect infection and fungal growth.

In this booklet we present the Vertical Soak Diffusion (VSD) method which uses minimally toxic borates as preservatives. The method has been tested in Indonesia using three species of bamboo: Dendrocalamus asper* Gigantochloa apus* Gigantochloa atter* If you are intending to use other species of bamboo, follow the methodology in this booklet to treat a small section (1-2 internodes) and observe the rate of penetration of the red dye discussed in step 14, page 18

Whereas bamboo treated by the modified boucherie system (a pressure system introduced by Prof. Dr. Liese, Hamburg, Germany) is appropriate for large scale plantations growing bamboo for construction timber, furniture, and some crafts the VSD system works well with small-plantation situations , and community development work in rural villages.

Managing Bamboo

Clumping bamboos are non-

invasive. They do not ruin

buildings, they grow very fast

when young and the culms

are larger than those of the

running bamboo. They require

little maintenance, although

simple clump management

will benefit both the grower

and the bamboos.

 

In the dry
season, almost all

culms that are 3 years or older

can be removed from a clump

by cutting them just above a

node about 20cm above the

ground. Some younger ones

have to remain for further

nourishment of the rhizome.

 

In
the shooting season, remove

any shoots that are going
to create

overcrowding (many
species are

edible, cooked). Leave
only the

shoots of good diameter
which

have potential to produce
straight

strong poles for timber
use.

 

 

Harvesting Bamboo

Dry Season

Wet Season

 

Harvest Bamboo during dry season

The best season for harvesting is after the rainy season when starch content in the bamboo sap is low. Starch is the favourite food for pests. Don't harvest during shooting season! Cut bamboo that is 3-5 years old. Bamboo older than 5 years is harder and the inner culm wall becomes impermeable to the BORAX BORIC ACID Solution.

There are 2 different ways to tell the age of bamboo culms:

1) Mostly, culms at the inside of a clump are the oldest.

2) Label the new shoots, this is the safest method.

 

The culms should be treated
soon after having been cut,
but can be left for a few
days standing upright,
placed on a stone. Due to
the ongoing transpiration
by the leaves the culm will
loose some of its moisture
and also starch, which is
the food for the pest, i.e.
the Powderpost Beetle.
But don't wait too long,
since moisture is required
for the following diffusion
process.

 

The Powderpost Beetle

Stored bamboo is endangered by beetle infestation which can be recognized in the form of a talcum-like powder and small holes in the area of the nodes and along the internodes.

Planning a Treatment Center

Floor
Pan

Elevation View

Floor plan Treatment Area

Tools and Materials


Eye Protection

 

Hacksaw

Rubber Gloves

Iron Rod with hex Nut 

Rubber Boots

Bamboo Stick for Stirring

Boric Acid

Pump

Plastic Containers Mixing & Measuring

Small Sum pump

Red Textile Dye Aniline

Rubber Hose

Water

Node Punch

Filter 

Hydrometer 

Containers For Solution

Brushes for cleaning 

Rope (for tying culms) 

 

Mixing the Borax Solution

STEP 1

Calculate
the internal volume of the culms.

There are 3 differrent ways to do this:

1. Volume in liters = inner radius squared x 3.1416 x height in
cm of culm divided by 1000.

Example: bamboo with radius = 6cm, height
= 400cm

((6x6)
x 3.1416 x 400)) / 1000 = 45 liters

2. Fill one punctured culm with water and simply measure how many liters it takes to fill it up. Multiply by the number of culms.

3. Fill one average internode; measure the amount in liters and multiply by the number internodes and by the number of culms.

 

STEP 2

Mix
3 kg of BORAX with 2 kg of BORIC ACID and add 45 liters water. This

gives a 9 to 1 or 10%
solution

Borax 3kg
Boric Acid 2kg

Water 45 litres

1.5 litres each

 

STEP
3

 

Add red analyn textile dye. It should completely penetrate the tissue of the culms from the inside all the way to the outside skin. If the particles of the dye are too large they will only partially dissolve and "plug" the openings in the tissue thus preventing penetration of the preservative.

 

  

STEP
4

 

Slowly add water stirring constantly until BORAX/BORIC ACID and dye are completely dissolved and no more crystals are at bottom of container.

 

STEP 5

Test
the solution with a
hydrometer
under normal
temperatures of your region.

 

Fill a small test container with
the Borax/Boric Acid
solution slowly, so as to
not form air bubbles.  Lower
the Hydrometer into
the container and give it
a  quick twirl like spinning the
top. 

This
will get rid
of
air bubbles that might
have accumulated on the
hydrometer.  

Then
read the number
where
the solution crosses
the scale on the hydrometer,
like reading
a thermometer: 1.035 (or whatever
a close number
is) will be your benchmark
for re-testing the solution later.

 

STEP 6

Thoroughly
clean the

outside of the bamboo

culms with water and
brushes (or coconut husks

and sand, or scotch brite)

 

 

STEP 7

Weld hex nut
to one end

of iron rod. With this
rod
you can punch
holes
through the
diaphragms.

The
hex nut will create
large
diameter holes thus
preventing
air bubbles from
forming
in the culms during
the
filling procedure.

 

 

STEP 8

 

Place
the bamboo against a

wall. Insert the iron rod
and

punch holes through the
nodes.  Make
sure the last node is
not
punctured.

 

 

STEP 9

Move the bamboo to the

concrete basin.
Stand up vertically.
Tie culms securely
together
so that
they cannot move
when
they are being filled
with
the BORAX/BORIC
ACID
SOLUTION. Culms
become
very heavy when
filled.

 

STEP 10

 

Connect a hose to the container which holds the mixture. Pump the solution into the culms.

STEP 11

Fill the entire bamboo with the solution.  Every morning refill the culms which have absorbed approximately 1% of the liquid overnight. Every day absorption rate is less.

 

STEP 12

On Day 13 don't add more
solution.

 

Allow the level to go down to avoid overflow when the last node is broken.

STEP 13

On Day 14, test check the

culm by sawing off the

upper internode. The
fabric
dye has now
penetrated
the culm
walls sideways
and coloured
them pinkish.
  Carefully
carry the filled
culm
close to the sump hole
and
break the last node
using
a metal punch. Make
sure
you wear face
protection.
The diaphragms of large
culms should be punctured
by using the iron rod.
The solution will now flow
on the sloped basin floor
into the sump hole.

 

STEP
14

Leave the
bamboo for a minimum

of one hour in the basin
for the
solution
to fully drain out of culms
into
the sump hole.
  Pump
leftover solution back into
container
through a filter for re-use. The filter should be regularly
changed.
Test again with the
hydro
meter and add more
BORAX/BORIC
ACID if necessary
(see
appendix page 23). Wipe down
the
whole culm to remove excess
borate.

 

STEP 15

 

Store the bamboo horizontally or vertically in the shade (hot sun splits it) to slowly dry. Make sure that it is not exposed to rain which could wash out the preservative.

Information
about Borates

BORAX/BORIC
ACID is more environmentally friendly than other

wood preservatives currently used.  
Reuse
Guidelines

The BORAX/BORIC ACID SOLUTION can be used more than once for treating bamboo, as long as the hydrometer reading of the solution is still at the initial level, of approximately 1.035. 

Keep in mind that, as the bamboo sap gets partially drained out of the culm, the starch/sugar from the sap will move into the treatment solution. This can lead to inaccurate hydrometer readings. After the 3rd or 4th use gradually increase the BORAX/BORIC ACID concentration to 1.040 and 1.050. 

At the point when the drained solution foams significantly and/or mold is forming on the surface of the solution and on the bamboo culm it is time for the solution to be disposed of. 

Disposal Guidelines

BORAX/BORIC ACID is non toxic to the environment, but is highly
saline. 
When a moderate amount of it is absorbed into the ground, the ground filters out the salt to the point where it does not pollute the ground water. However, it is advisable to dispose of it safely and out of reach of children.  When diluted with more water the discarded solution could be used as a herbicide on terraces and walkways.

Where
to buy BORATES in Indonesia

PT CHIMIFIN JAYA UTAMA, JAKARTA

Tel 021-424-0202, 424-7141, 425-5563

Fax 420-5588

UD. Saba Kimia, Denpasar,

Tel/Fax 0361-410662