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.

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

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.

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 ((6×6) 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 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