Cargo can consist of different types of solid fuels,
such as thermal coal, metallurgical coal, pulverised
coal injection (PCI) coal, anthracite (raw material or
in screened fractions), metallurgical coke (raw
product or screened in several fractions) and petcoke
(run of coker or screened fractions), as well as solid
biofuels in several commodities. Each commodity has
individual characteristics based on the different
possible global origins. Due to this, each commodity
has to be sampled, inspected and prepared in its own
specific way, in order to obtain the most reliable end
results.
These services are performed according the
international ISO-18283 Standard for sampling and
sample preparation of solid fuels. It is generally
accepted that the number of sample increments
should be based on lot size and sampling variance
with increment weight being determined by
considering maximum particle size. RC Inspection
has developed its own specific sampling and
inspection procedures, according to its 40 yr of
experience and based on the above mentioned ISO
standard.
Sampling and the visual inspection of the cargo
are complicated processes and will become more
complicated and important in the near future, due to
the heterogeneity of the cargoes based on the
origin of the commodities and their characteristics.
The surveyors need to know the visual
characteristics of each different commodity to be
able to perform accurate inspection, sampling and
sample preparation. Throughout the visual
inspection, the condition and the appearance of the
cargo is important, as it may have an impact on the
quality, due to possible contamination and/or
free water.
When samples are taken from a stationary source,
such as a stockpile, it may be impossible to obtain an
accurate sample due to the fact that the material in
the centre of the stockpile may be inaccessible when
conventional sampling techniques are used. When
samples are taken from a moving stream, such as a
conveyor belt, the requested increments have to be
collected at the place of the stockpile. The sampling
must be performed where the cargo is leaving the
conveyor belt system in order to obtain the most
representative increment-samples. Samples collected
from a moving conveyor belt, is banned at all
European terminals due to safety reasons.
Poor sampling and sample preparation will lead to
non‑representative analytical results. This is best
disregarded because the obtained samples will have
no reliable value at all.
The used sampling equipment is evaluated
according to its effectiveness in obtaining a
representative sample according to the accepted
standard. To ensure quality sampling, RC Inspection
uses ISO-approved shovels. Samples taken from a
Thermogravimetric
Analyzers
ELTRA’s TGA
Thermostep
determines various
parameters such as
moisture, volatiles
and ash at user-
defined temperatures
and atmospheres in
a single analysis.
n
Fast heating rates,
high temperature
constancy
n
Analysis of up to
19 samples
n
Crucible lids can
be removed during
analysis
