EntrePinoys Atbp.

BRICKS AND TILES FROM RICE HULL ASH AND CLAY

The high cost of construction materials for housing and the need for enough shelter lead to this simple procedure. Rice hull is used in cooking bricks. The produced ashes is used in the mixture of bricks. These materials can be found anywhere in the Philippines.

Materials needed:

• clay
• rice hull
• rice hull ash

Tools needed:

1. Oven or kiln with 3m x 5m measurement. (Open on top and made of red clay.)
2. Shovel, hoe and tool for digging.
3. Wood or metal mold with inside measurement of 2″ x 4″ x 10″ for red clay and 3″ x 8″ x 12″ for floor tiles.
4. Wood or metal for scraping.
5. Drying place (like table)
6. Hole about 3mx2m with water.
7. Mixing container — wood or concrete.

Procedure:

A. Bricks

1. Dig clay and bring to the hole with water.
2. Soak for a day.
3. Transfer mud clay in the mixing container and add rice hull ash: 1 part of ash to 3 parts of clay.
4. Mix well by foot. Remove roots, leaves and other wastes.
5. Prepare the molds (metal or wood). Wet inside surroundings and sprinkle with ashes.
6. Pour the mud clay mixture.
7. Scrape excess from mold.
8. Remove from the mold carefully.
9. Let it dry under the shade for a day.
10. Let it dry under the sun for 5-7 days.
11. Arrange the pile of brick tiles before firing.
    • a. Place 30 cm thick rice hull ash under the oven. Arrange the pile of bricks at 5 cm apart from each other and 15cm from the side of the oven.
    • b. Cover with rice hull ash, including the space between piles. Cover the first pile with 5cm thick of rice hull ash. Do the same in the second and next piles.
    • c. This size of oven can accommodate 1,200 bricks.
    • d. Ignite rice hull ash starting from the bottom. This will last up to one week. Leave bricks to cool.

B. Brick Tiles

• The method of making brick tiles is similar to bricks. They differ only in size and shape.
• Both sides of the floor must have a 1 inch groove.
• A laborer can make 200 bricks in a day.
• An open oven with 3m x 5m size can cook 1,200 bricks in a month.

HOLLOW BLOCKS FROM AGRICULTURAL WASTES

Materials:

• 1 part of cement
• 3 parts of: sawdust, soil, rice hull, wood shavings, wood chips, crushed coconut trunk

Procedure:

1. Mix well, add enough water to desired consistency.
2. Put in mold and place under the shade for a few hours.
3. When dried, remove the blocks from mold to dry and incline to one side for ten (10) days. Sprinkle with water from time to time to prevent cracks.

HOLLOW BLOCKS FROM COCONUT HUSK

Materials:

• powdered coconut husk
• sandy soil
• cement

Tools:

• molds (made of heavy wood or iron)
• shovel

Procedure:

1. For every part of cement – 6 parts of coconut husk soil (or 50 – 50 coconut husk and soil or powdered coconut husk only).
2. Refine and strain soil on 1/4″ wire mesh strainer.
3. If rice husk have long fibers, cut it to 1 inch size.
4. Measure cement and other materials. It is better if the inside diameter of the container measures 30cm which is enough for one bag of cement.
5. Mix the ingredients well with the aid of shovel.
6. Make a mountain with hole at the center to pour water. Mix well to attain desired consistency.
7. Put in a “hollow block” shaped mold the mixture of cement and rice husk. Lay mold on its side on top of a level platform. Fill the mold completely and scrape excess.
8. Place flat wood on top of the mold and invert it. Compress it like the first one and scrape the top. If necessary add more mixture of cement and rice husk/soil.
9. Remove the three sets of blocks from the mold. Remove the lock and push carefully the molded block.
10. Let the block dry under the shades for a few hours to one day after removing from the mold. In drying let it lie on longer sides so it will slide on the longer side.
11. Let it age for 10 days outside. Sprinkle water from time to time to prevent cracks.

The blocks can be used for walls or fence which will not carry weight.

HOLLOW BLOCKS FROM RICE HULL (or Rice Hull Ash Cement – RHAC)

Procedure:

1. Burn rice hull into ashes.
2. Refine the ashes.
3. Mix the ff.:
   • 60 parts of cement
   • 40 parts of rice hull ash
   • water
4. Put in a wooden mold.
5. Let it dry.

Part 1 | Part 2 | Part 3

For more information, contact:

Dept. of Science and Technology
Rm. 303 DOST Bldg., DOST Complex,
Gen. Santos Ave., Bicutan, Taguig City 1631
Telephone Nos: (632) 837-20-71 to 82
Fax: (632) 837-8937
Web: www.dost.gov.ph

photo from www.strawbalehome.com