18
Hoval STU Wood Pellet Boiler
Design Guidelines
Fuel Store Sizing
There are 3 key factors that influence the size of the pellet store.
1. Available Space - usually adjacent to or close to boilers - taking account of best use of that space.
2. Estimated Fuel consumption.
3. The required frequency of delivery - or the size of delivery anticipated.
For Design purposes the following can be used as indicative:
1. Bulk density or Volume of Wood Pellet Fuel;
• Good quality wood pellet fuel will occupy approximately 600kg/m3
• Angle of repose of good quality fuel approx 45º - 55º - which impacts on recoverable volume in bunker.
2. Fuel Consumption;
• As an indication the maximum fuel consumption (kg/hr) would be 0.23 x Max Output of the Biomass boiler (kW).
• Actual fuel consumption would be estimated based on the loading placed on the boiler.
• Wood Pellet fuel store to be sized to accommodate a minimum of 10 - 15 days anticipated fuel use.
3. Delivery Size;
• The fuel supplier will have preferred bulk delivery sizes - based on payload of vehicle employed.
• Store should be sized to accommodate minimum delivery size.
• First Fill delivery could be larger than subsequent deliveries. Accounting for possible dead volume within the store
and making allowance for small working stock needed while waiting for a delivery.
Consider the possible use of load cells or level probes within the bunker to indicate fuel used.
Hoval can offer a number of silo based fuel store options or advise on most appropriate use of available space for a bespoke build fuel
store.
Entry to Fuel Store
A confined space permit to work system should be put in place by the operator, to safely control access and egress into the fuel store itself.
