How to make hollow blocks

CEMENTLESS SOIL BLOCKS 

 In view of the rising cost of cement, the Forest Products Research and Development Institute made an attempt to form building blocks out of soil and water alone or in combination with one or two other agri-forestry waste materials, such as rice hull, coconut coir dust and wood ash. Lime is used as a binder. Lime is found in large quantities in Rizal, Negros Occidental and Davao Oriental. Coconut coir and other materials are available almost nationwide. 

Materials: Lime Soil Coconut coir Sand Rice hull Wood ash Rice hull ash 

Equipment: 1/4 inch mesh screen mold shovel 

Procedure: 1. Pulverize the soil and remove larger pieces with the use of a 1/4 inch wire mesh screen. 2. Mix together soil and any one or two of the agri-forestry wastes. Suggested combinations (in parts by volume) are: a. 3 soil + 1 coconut coir b. 3 soil + 1 rice hull c. 5 soil + 1 lime d. 5 soil + 1/2 lime + 1/2 rice hull ash e. 5 soil + 1/2 lime + 1/2 wood ash f. 4 soil + 1 rice hull + 1 lime g. 21/2 soil + 21/2 sand + 1/2 lime + 1/2 wood ash

3. Form a hill out of the dry mixture (or of soil alone if a pure soil block is to be made) with a crater on top and add water. 4. Pour water slowly and with a shovel, mix the materials until a paste is formed. The paste should neither be too dry nor too wet so that during the molding process. The ingredients are wet enough to stay packed but not too wet to produce slump when the product is removed from the mold. The right mixture can be learned easily by experience. 5. Fill the mold with the mixture. Tamp very well and level off. Apply pressure using a manually-operated molding machine or a similar device. 6. Dry the block in the shade for a few days and then sun dry for another few days. 

Source: Forest Products Research and Development, Institute (DOST) College Laguna 

LIME-CLAY-SAND BLOCKS 

With the materials that are available all over the country, Industrial Technology and Development Institute fabricated blocks which need no firing. The block has a square face and grooved sides which allow adequate surface for bonding. It measures 8"x8"x6". The provinces of La Union, Bulacan, Batangas, Quezon, Bohol and Negros Occidental have reserves of all the 4 non-metallic ores herein used. Clay and limestone may be found in almost all the regions while sufficient amount of sand and gravel occur in Regions III, IV, VI and X. 

Materials: Clay Gravel Lime Water Sand 

Equipment: Pickax Wire mesh screen Shovel Wooden measuring box 

Procedure: 1. Crush the lumps of clay into smaller pieces with a pickaxe. With the use of a wire mesh screen, remove impurities, such as stones, roots, twigs, etc. 2. Sift the lime and the sand separately to remove the bigger particles. 3. Mix thoroughly five (5) boxes of clay, two (2) of lime and two (2) of sand. 4. Add water slowly until the right consistency is reached. The mixture should neither be too wet nor too dry so that when molded, the block will maintain its shape. 5. Press the mixture into a wooden mold until all spaces are filled up and scrape off the excess. 6. Remove the mold and allow the formed block to stand in the shade for 3 days. Then sun-dry for another 3 days. 

Source: Ceramics Research Division ITDI (DOST) 

HOLLOW BLOCKS FROM RICE HULLS 

Procedure: 1. Carbonize the rice hulls. 2. Pulverize the ash. 3. Mix the following:60 parts cement40 parts carbonized ashwater 4. Pour the mixture into wooden molds 5. Allow to dry. 

Source: Forest Products Research and Development , Institute (DOST) Los Baños, Laguna. 

HOLLOW BLOCKS FROM WASTE MATERIALS 

 A new type of hollow blocks can be fabricated out of wood wastes, agricultural wastes and soil mixed with minimum amount of cement. As far as strength and durability are concerned, results of test showed that this type of blocks is comparable to some of the commercial or traditional concrete hollow blocks. However, they are considered as strictly non-loading bearing. 

Materials: 1 part cement 3 parts sawdust, ordinary soil, rice hulls, abaca waste, sugarcane bagasse, coconut coir dust and coconut trunk. Procedure: 1. Pulverized soil is passed through a wire screen, 1/4 inch wire mesh to separate larger pieces. A mixture of 1 part cement to 3 parts agri-waste is formulated. 2. Mix all materials together, add water and pour into molds. 3. Let stand for several hours until dry. 4. After drying, remove from molds and let stand along one side for 10 days while sprinkling water at regular intervals to avoid cracking. 

Source: PCARRD Farmnews December 1988, Photo courtesy of www.hindu.com

Duck Raising

Remote coastal areas often lack the supply of poultry meat and eggs essential to good nutrition and health. If it is available, the price is more expensive compared to urban centers. One alternative is duck (itik or bibi) raising. Duck raising does not need much labor and care. This allows mothers, children or other members of the family to engage in a profitable food-based enterprise. Ducks are efficient producers of animal protein for the family and provide extra income. Ducks require simple shelter, are resistant to common poultry diseases and can thrive on feeds locally available. It is an economical, useful and multipurpose water fowl appropriate to coastal areas. They grow best along watered areas. The presence of mangroves, seagrasses and coral reefs in most coastal areas are rich natural sources of food. Ducks are voracious eaters and efficient scavengers. In many coastal areas where malarial disease is prevalent (because of the presence of mosquito larvae that thrive in brackishwater), duck raising can minimize-if not control-its incidence by feeding on mosquito larvae (worm-like). However, a few crops in coastal areas can also be destroyed by ducks.

Duck (itik or bibi) 

Breeds 

The traditional multipurpose breed is white or black; the most commonly raised in most rural areas, it can lay 100-120 eggs per year. The improved Pateros breed can lay 120-200 eggs per year. The egg-type Khaki Campbell breed can lay 200-250 eggs per year. Newly-introduced hybrid-egg types, like CV-2000, can lay 250 eggs and up. The recommended breeds for coastal areas are Muscovy and Pateros (mixed colors). 

Different production methods 

 There are four commonly used production systems in the Philippines. 

Scavenging system This is most widely used in coastal and inland areas. A flock of 3 and below are allowed to range free over the village and return to the homeyard in the evening. 

Herding system Growing or laying ducks is allowed into wet lands, irrigation areas or harvested paddy fields scavenging for food during the day. They are herded into enclosures during the evening and night. If the natural feed supply is exhausted, they are transferred to other feeding sites. 

Landing system This is common in South Kalimantan (Borneo), Indonesia, where vast tracts of swamplands are available. The ducks arc provided with floating houses with fences on rafts. They feed on aquatic animals and plants given to them or by scavenging. 

Confinement or intensive system This is practiced by commercial growers with large flocks of more than 100 birds. They are kept in pen systems with shelters and are fed with available, commercial feeds. 

Proposed design of duck shelter in coastal areas. 

Management and care 

 A household may start with 15 birds of 13 female (ducks) and 2 males (drakes), as its source of food and income. Most houses within tidal fluctuations have their own open porch for drying fish, etc. One can build the ducks' shelter under the porch or under the house. A one-half meter clearance from the highest tide level area should be allowed below the flooring of the ducks' house. A three-feet clearance from the family house floor to the ducks' house floor is enough. This can be done by using bamboo slats that are closely nailed to the flooring. Bamboo fences may also be provided. Place rice straw or other grass materials on the floor as litter. Provide nests for laying or brooding. One can use bamboo, discarded tires or other containers as feeders. Also, provide ladders. Ducks in coastal areas usually perform well because of the presence of aquatic and marine animals, like fish, snails, larvae, etc., and water plants, such as algae and grasses which they can feed on. Supplemental feeding may be done with kitchen leftovers, trash fish, rice bran, corn, cassava and other grains that can be bought for extra feeding, if necessary. Allow at least two to three ducks to brood their eggs as replacement stocks. The rest of the eggs may be used for family consumption and/or sale. Peak laying of ducks is 18 months after six to seven months. Dispose or sell all the flock after the 1 8-month period, if there is a replacement available. If the village has a history of recurring common fowl, diseases like Avian Pest, Fowl Pox and Fowl Cholera, request the services of the Municipal Livestock Technician for vaccination of the birds. 

Economics of production—duck raising 

 Raising ducks may be a profitable project, especially in a rice-growing area with sufficient supply of water. Based on the experience of Mr. Antero Villareal of Barangay Plaridel, Llanera, Nueva Ecija, who started with only 200 ducklings in his 500-sq-m backyard and P7,000 as seed capital, a net profit of P17,850 from sales of fresh duck eggs was realized after five months. In 1987, he again bought 2,500 female ducklings at P8.50 each from Pampanga. He earned a net profit of P 150,000 from the eggs laid by 900 ducks in 1989 and used the money to buy the 20,000 sq m ricefield he is cultivating. Today, he owns a balut factory and his 800 ducks provide most of his freshegg requirements: 600 for sale daily; 2,000 for salted eggs; 12,000 for balut production every three days; and 3,000 for hatching every week. His market extends up to the Munoz-San Jose City area (Greenfields, June 1993). Source: IIRR