Rice Hulls for Composites - Introduction to Polymeric Composites with Rice Hulls - page 66

On a contract received by a group of businessmen in the Philippines, I set up a complete
manufacturing plant for three sizes of Styrofoam fish boxes to include project design,
factory building, machinery, technology, and training. To save initial project costs and
not delay the start of production, the supply of steam was taken from the neighbouring
factory, which was manufacturing silk threads from silk worms. Interestingly, their
steam boiler was fuelled by rice hulls in the natural state. This system was quite
advanced and more or less automatic, with effective collection of ash to the ground.
During the second year of operation, the producer of Styrofoam fish boxes, on my
recommendation, installed his own steam boiler system fired with rice hulls with
automatic operation. Rice hulls were freely available locally, which enabled this
producer to minimise fuel costs.
5.4.13 Rice Hulls in Building Construction
I present some polymeric composite products with rice hulls other than the number-
one product: composite lumber in building construction. Over the years, people have
used natural wood in all types of construction work: domestic, industrial or other.
Natural wood has a very wide range of applications but, due to rising costs and
particularly serious environmental concerns with deforestation on a global scale, it
was merely a matter of time before people would find alternatives.
One such product is roof tiles. Mixtures of polymers (pure wastes or recycled), mixed
with rice hull flour, a small percentage of cement, additives and colours, has led to
production of roofing tiles with excellent properties and a wide range of finishes and
shapes. The practice of using polyethylene or polyvinyl chloride as the polymer matrix
will no doubt extend to other polymers. Another product is floor tiles based more
or less on the same formulation mix. One big advantage is that wastes can be used,
with probably the ideal being recycled wastes in pellet form for easy compounding.
Using this same concept, strong roofing sheets in any colour or shape can also be
produced and, according to reports, are already in use.
The possibilities of rice hulls and their ash have many exciting and challenging
possibilities of applications, and even the producers of polymeric composites are
coming up with interesting products. In fact, the actual producer is probably the most
knowledgeable source with first-hand information to initiate practical new products.