Requirement
ENplus-A1
*1
DINplus
ÖNORM M 7135
Diameter
mm
6±1
—
—
Length
mm
3.15 ≤ L ≤ 40
A maximum of 5 % may be lon-
ger than 40 mm, but no longer
than 45 mm.
—
—
Bulk density
kg/m
3
≥ 600 (600 to 750)
—
—
Net calorific value (when
free of water)
MJ/kg
≥ 16.5
≥ 18
≥ 18
kWh/kg
≥ 4.58 (4.6 to 5.3)
≥ 5
≥ 5
Water content
%
≤ 10
≤ 10
≤ 10
Percentage of fines
(particles shorter than the
specified length of
3.15 mm)
%
≤ 1
—
—
Mechanical strength
%
≥ 97.5
—
—
Abrasion resistance
%
—
≤ 2.3
≤ 2.3
Ash content
%
≤ 0.7
≤ 0.5
≤ 0.5
Ash softening temperature
°C
≥ 1200
—
—
Chlorine content
%
≤ 0.02
≤ 0.02
≤ 0.02
Sulphur content
%
≤ 0.03 (≤ 0.04)
≤ 0.04
≤ 0.04
Nitrogen content
%
≤ 0.3
≤ 0.3
≤ 0.3
Copper content
%
≤ 10
—
—
Chromium content
%
≤ 10
—
—
Arsenic content
%
≤ 1
—
—
Cadmium content
%
≤ 0.5
—
—
Mercury content
%
≤ 0.1
—
—
Lead content
%
≤ 10
—
—
Nickel content
%
≤ 10
—
—
Zinc content
%
≤ 100
—
—
Compression additive
%
—
≤ 2
≤ 2
External production control
—
Yes
—
Pellet quality characteristics
High quality pellets:
■ Smooth, shiny surface
■ Uniform length
■ Low proportion of dust
■ Sink in water
Low quality pellets:
■ Cracked rough surface
■ Widely varying length
■ High proportion of dust
■ Float in water
Types of pellet delivery
In their loose form, pellets are transported by silo tanker and pumped
into the storage room via a hose system.
Careful handling of pellets ensures a low proportion of dust, trouble-
free boiler charging and a constant heating output by the solid fuel
boiler.
1.3 Principles of woodchip combustion for generating heat
What are woodchips?
Woodchips are made from 100 percent natural wood from forests and plantations. This raw material comes from tree trunks or branches. The
wood is then processed with high speed cutting tools in accordance with ÖNORM M 7133.
Definition of woodchip size classes according to ÖNORM M 7133
Total mass
100 %
Woodchip size classification
G 30
Fine
G 50
Medium
G 100
Coarse
Coarse percentage
up to 20 %
Max. cross-section
cm²
3
5
10
Max. length
cm
8.5
12
25
Coarse sieve nominal mesh
width
mm
16
31.5
63
*1
The essential properties of wood pellets are described in European Standard 14961-2. EN 14961-2 will be superseded in 2014 by international
standard ISO 17225. Once ISO 17225-2 is published in 2014, the values in brackets will replace the previous values.
Principles of wood combustion
(cont.)
VITOLIGNO 300-H
VIESMANN
7
5672 507 GB
1