Background: 

Raw water contains suspended impurities and pathogenic bacteria, which are responsible for water borne diseases, like cholera, typhoid, jaundice, etc. these contaminants have to be removed to make the water safe for drinking purpose. One of the well know method is to filter water through beds of sand, gravel and charcoal to remove suspended impurities, followed by boiling to kill the bacteria. This process, though efficient, is costly and time consuming. To simplify the treatment of water, inexpensive domestic Water Filter Candle has been developed. The main items of plant and machinery required are crusher; ball mill, sieves and coal-fired down drought / electric / oil fired furnace.

 Application:

The candle (s) can be fitted to various types of domestic containers for getting bacteria free potable water.

 Process:

The process for the production of filter candles consists for grinding the non-plastic materials (china clay, insulated brick powder, quartz, feldspar, etc.), mixing with organic materials and casting the candles in moulds of desired shapes. The candles are dried sun and then baked in furnace.

 Status of commercialization

Process has been released to 45 parties in India and 1 in Indonesia.

An investment of around Rs. 5.80 lakhs is needed to establish a unit to produce 100 candles per day. Cost of production of a candle is Rs. 30 and the unit provides implement opportunity for 10-12 persons.