Question

Problem: What is the net annual savings if the sawdust is burned?
Given: A large furniture plant develops 10 tons of sawdust (@6,000 Btu/ton) per day that is presently hauled to the landfill for disposal at a cost of $10/ton. The sawdust could be burned in a boiler to develop steam for plant use. The steam is presently supplied by a natural gas boiler operating at 78% efficiency. Natural gas costs $5/MMBtu. Sawdust handling and in-process storage costs for the proposed system would be $3/ton. Maintenance of the equipment will cost an estimated $10,000 per year. The plant operates 250 days/yr.