PRODUCT INFORMATION
INDEX
DATE
Dep. 2
IC-G-D-30-001e
D
March 2014
FUEL SPECIFICATIONS FOR GAS ENGINES. GENERAL
2/5
3.
ANALYSIS OF FUEL GAS
For the characterization of the gas to be used as a fuel, it will be necessary to carry out a chemical analysis of the
same. Such an analysis will be made first in order to select the type of engine required and to check the gas
conformity with the specifications for its use as an engine fuel. Additionally, gas analysis shall be conducted
whenever harmful constituents are suspected to be present in the gas as well as from time to time as part of the
installation monitoring.
3.1. SAMPLING FREQUENCY
For all the specified types of gas, the sampling frequency will be determined as follows:
Project Phase:
At least one complete analysis shall be made for each application.
Start-up Phase:
During the first year, analysis shall be made at least every six months for natural gas, every
three months for landfill and digester gas, and every month for gases resulting from thermochemical processes.
Operation Phase:
Once the gas properties have been found stable (one year without relevant variations), the
following minimum analysis program can be established: once a year for natural gas, once every six months for
landfill and digester gas, once every three months for gas from thermochemical processes.
The intervals of the above analysis program may be increased, provided the stability of the supplied fuel gas has
been demonstrated.
3.2. ANALYSIS LABORATORIES.
Kohler
can advice the customer on the availability of laboratories where to make the required gas composition
analysis.
In any case,
Kohler
reserves the right to carry out its own analysis on fuel gas fed to
the engine.
4.
CONTAMINANTS AND FACTORS AFFECTING THE ENGINE OPERATION
The fuel gas contaminants and factors affecting the engine operation fall within these categories:
-
Important variations in the fuel gas composition and conditions of supply.
In case there are variations in
the composition, pressure, temperature and humidity of the fuel gas affecting its basic specification
parameters (see point 2.1), their effect can be the engine breakdown or operation in conditions beyond those
advisable. By important variations, we mean also those which are within the fuel specifications but differ by
±5% from the design value given to the manufacturer or the engine start-up conditions. At times, a small
adjustment will suffice to adapt the engine to the new conditions; but any change whatsoever in the supplied
gas conditions over the aforesaid limit must be reported to the engine manufacturer or maintenance staff who
will come to tune the engine as necessary.
-
Contaminants that cause abrasive wear to the engine components.
These include all the substances
contained in the gas, which circulate at high speed inside the engine, either upstream or downstream of the
combustion chamber, and may therefore cause abrasive wear to different parts of the engine, leading to
engine failure or to a reduction of its life expectancy. Belonging to this category are such compounds as
siloxanes, gas combustion salts, metal particles, oils, tar, etc.
-
Contaminants that corrode the engine components.
This category refers to those substances which, due
to their chemical nature, are capable of attacking both the metallic parts and the fluids of an engine, and thus
leading to engine failure or to a reduction of its life expectancy. Within this group are acids compounds,
4.1.14
O&M_2.002211.810_A_10_2016
