Commissioning
HDK-CNG_EN_03_2016
35
Depending on the transportation and storage conditions, the drying agent in the
vessels can already be loaded with humidity from the environment. At each first
start-up it makes sense therefore to operate the dryer for some time separately
from the compressed air system. This causes the drying agent in each vessel to
be regenerated repeatedly and thus to be prepared optimally for the take-up of
humidity.
If you wish to take the dryer into operation in accordance with our
recommendation, proceed as follows:
► Ensure that the natural gas valve installed by the owner is closed.
► Keep natural gas outlet valve closed for the recommended period of time.
Then the dryer can be taken into service in the natural gas system as described
in the following section:
Immediately operate dryer in natural gas system
► Ensure that the natural gas system downstream of the dryer is pressurised or
that a start-up device was installed into the natural gas system directly
downstream of the dryer.
The importance of this increases with the size of the natural gas system
downstream of the dryer. Smaller natural gas systems can also be
pressurised by the natural gas directed through the dryer.
Slowly open user-installed natural gas outlet valve!
Avoid a sudden drop in pressure in any circumstance! If pressure drops
too fast, this may cause damage to the dryer. For that reason, always
open natural gas outlet valve slowly!
► Slowly open user-installed natural gas outlet valve. Observe the vessel
pressure gage of the pressurised vessel. The pressure should not drop below
the 80% of the operating pressure if possible. If necessary, keep the natural
gas outlet valve in a slightly open position until the natural gas system
downstream of the dryer has filled up completely. Do not open the valve fully
until that time.
The dryer is then in operation in the natural gas system.
In the event of a fault
►
When critical gases flow through:
First purge the relevant section of pipework, the dryer and the filters with inert
gas.
►
With ATEX-compliant dryers:
Cancel the Ex zone (in acc. with owner's operating instructions).
►
All gases:
—
Block gas supply to the dryer.
—
Depressurise the dryer.
► Look up possible cause of the fault, and how to remedy the same, in the
table on page 51.
► Rectify fault.
