Grant Spira 6-26kW, Инструкция по установке, наладке и обслуживанию

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3.1 Pellet specification .
This Grant SPIRA boiler is designed to run on wood pellets that meet the following criteria;
Key Parameter Limits Category as per
prCEN/TS 14961:2004
Diameter 6mm
D06,
Average length L<5 x diameter
Maximum length 40mm
Moisture Content <10%
S0.05
Mechanical durability >97.5%
DU 97.5
Amount of fines <1.0%
F1.0
Additives None
Nitrogen < 0.3%
N0.3
Nett calorific value
Ca. 4.8 to 5.2 kWh/kg
Bulk density
Ca 650 kg/m
3
Chlorine < 0.03%
CL 0.03
Additives;
Additives are used to improve the stability of the pellets. If manufactured correctly, and of a sufficiently
low moisture content, quality pellets will require no additives.
Ash; Ash represents the non-combustible content of the pellet. Higher ash content reduces the calorific
value of the pellet and requires the appliance to be cleaned more frequently.
Average length: To provide a predictable flow of fuel into the burner, the recommended length of a pellet is deemed
greater than 5mm and less than 5 times the diameter.
Bulk density; Bulk density is the ratio between the weight of the pellet and the amount of space they take up. A
good quality pellet will have a density of 650 kg/m
3
.
Chlorine; High levels of chlorine in the flue gases emissions can give rise to corrosion.
Diameter The most common diameter is 6mm with some 8mm also available. This boiler is designed for 6 only.
Fines Pellets are made from compressed wood. As pellets rub together they can break down slightly,
producing dust or fines. Too many fines indicate a poor quality pellet and can impede pellet flow in
addition to causing dust problems when delivering and storing the pellets.
Mechanical Durability This is a measure of how stable the pellet is and how likely it is to produce fines from normal handling.
A high durability percentage is an indicator of a good quality pellet.
Moisture content Moisture affects the calorific value of the pellet. Low moisture content guarantees constant and
predictable combustion efficiency. Higher moisture contents can result in pellet breakdown.
Net Calorific Value This is the useful energy contained in a kilogram of fuel. This value is affected by the amount of non-
combustible materials (ash) and the moisture content of the pellet. Typical values range from 4.8
kWh/kg to 5.2 kWh/kg.
Nitrogen High levels of nitrogen in the flue gases emissions can give rise to corrosion.
Sulphur High levels of sulphur in the flue gases emissions can give rise to corrosion.
3. Pellet Specification, Storage & Delivery