WOOD FIRED GASIFIERS TO REDUCE ENERGY COST IN

WOOD FIRED GASIFIERS TO REDUCE ENERGY COST IN

DESICCATED COCONUT INDUSTRY

Fuel oil fired boiler in a DC mill

Proposed wood fired gasifier

Under the guidance and the blessing of Vidyajothi Dr Ray Wijewardana, Vice Chancellor of University of Moratuwa and Mr P.G.Joseph, Director of Ministry of Science & Technology who are widely recognized as the pioneers of promoting “Dendro Power” in Sri Lanka, Haycarb Group of Companies of the Hayleys Conglomerate and Industrial Services Bureau (ISB) have joined hands to introduce wood fired gasifiers to reduce the mounting energy cost of the Desiccated Coconut (DC) industry.

Haycarb Limited has an excellent track record in developing local technologies and is one of the few companies, which invests heavily on R&D. It is a mandate of ISB to assist the local industry to be competitive in their respective market places by helping them to reduce their operating cost. Wood gasification is an inexpensive alternative for rapidly depleting and expensive fossil fuel. ISB, over the years, through its multifaceted service package has won the confidence and established good contacts with some vital industrial sectors such as desiccated coconut, tea, brick and tile, rice milling etc. Among these industrial sectors, DC industry has been identified as the first beneficiary of this new initiative. Under this partnership, Puritas Limited of the Haycarb Group will undertake the manufacturing of gasifiers and ISB will be responsible for canvassing/marketing/promotion of the technology and post commissioning maintenance services.

The main source of thermal energy for the DC industry has been imported furnace oil and diesel, which are very sensitive to the changing world market price of petroleum. In the light of the trends of increasing oil prices and unfavorable parity rates, adopting an alternate source of thermal energy is the only means by which this cost can be reduced. The DC industry currently consumes approximately 10 GWH of electricity from the national grid and around 12 million liters of fuel oil. The cost of this oil at current price of Rs 24.00 per litre is estimated to be over Rs 275 million in foreign exchange.

The purpose of this new initiative which is the introduction of ‘commercially grown wood fired gassifier technology’ is to assist the DC industry

to retain its competitiveness in the global market through the reduction of cost of production. In addition to the direct benefit to the DC industry, promotion of wood fired gassifier technology will derive multiple benefits such as the creation of an additional income source to the rural community by making them involved in the growing of commercial wood, fortification soil fertility by using waste green matter from wood and through the inherent nitrogen fixing ability of Gridicidia Sepium. Furthermore, it will derive local as well as global environmental benefits from the reduction of green-house-gases.

DC Millers Association is now seeking assistance of the Ministry of Plantation by way of monitory concessions to intended users of this technology or by way of funding a dedicated demonstration project in a selected DC mill. Such an intervention would undoubtedly contribute towards salvaging a nationally important industry which is now under threat both from supply and demand side. This technology, although developed more than a century ago is now coming into re-recognition. By this process the wood is consumed in a gassifier and is converted to Producer Gas, which is a highly combustible fuel with all the advantages of oil. The gassifier can be installed at a convenient location for the storage and handling of the wood supplies and gas can be transported in ducts to the location of the consumer of heat such as the boiler. As such any installation currently using oil as the source of energy can be converted for use of producer gas conveniently and at very low cost.

It has been calculated that the total requirements of wood for the 66 DC Mills now operating in the country is around 50,000 Tons annually, and thus can be grown in 5,500 hectares of coconut lands as an intercrop. As such the availability of wood for the gasification is not a matter of concern for the proposed conversion. The Gassifier technology lends itself readily to replace the oil fired burners for the boiler with producer gas burners fed from the Gassifier. The oil fired burner and the fuel system can be retained for use, during the Gassifier maintenance shut down or as a back up. Thus is the change over for oil to wood as a source of fuel can be affected with minimal modification to the existing equipment and a small capital out lay for only the Gassifier and associated equipment. The current usage of about 100 L/hr of furnace oil for a 2,000 Kg/hr steam capacity DC mill will be replaced by 350 kg/hr gasifier fired with Short Rotation Coppice (SRC) wood such as Gliricidia Sepium . The current price paid for Gliricidia delivered to the factories in stick form cut to required size for feeding the gassifier is Rs.2,000/- per ton at 20% moisture content. Investment could be recovered in 2,400 hours of operation.