34
6.2 - Concentration measurement method
This is the procedure used to measure the absorbent and
refrigerant concentration.
6.2.1 - equipment to use
•
Sampling cylinder
•
Gravimeter
Scale: 1.0-1.2 (for refrigerant)
Scale: 1.4-1.6 (for diluted absorbent)
Scale: 1.6-1.8 (for diluted, intermediate and concentrated
absorbent)
•
Thermometer
6.2.2 - Precautions
•
Take care not to damage the gravimeter and thermometer.
•
Be careful not to spill any solution. Do not fill the
sampling cylinder more than about 80%.
•
Perform this measurement quickly.
6.2.3 - Procedure
•
Fill the sampling cylinder to about 80% with the solution
to be measured.
•
Keep the sampling cylinder vertical, and insert the
gravimeter into it.
•
When the gravimeter stops moving up and down, read its
scale which shows the gravity of the solution.
•
Remove the gravimeter and put it aside. Then insert
the thermometer into the sampling cylinder and stir the
solution thoroughly.
•
When the temperature stabilizes, read the scale on the
thermometer.
•
Remove the thermometer and put it aside.
•
Store the solution in another bottle.
•
Using the concentration diagram of the lithium bromide
solution, read the concentration.
•
Upon completion of the measurement, wash the
gravimeters, thermometer and sampling cylinder with
water, and store them so that they are not damaged.
example:
The horizontal axis represents temperature and the vertical axis
represents relative density. The lines going down from left to
right represent the fixed concentrations.
For example, if the relative density is 1.77 and the temperature
is 45°C, the concentration given by the point of intersection of
the lines projected from these values will be 63%, as shown in
Figure 34 below.
Fig. 34
r
elative density
Concentration (%)
temperature (°C)
0 4 5
1.77
64
63
62
6 - iNstrUCtioNs
6.1 - absorbent sampling method
This instruction describes the procedure for sampling a small
amount of the absorbent.
6.1.1. equipment to use
•
Sampling cylinder and attachments for service valve
•
vacuum rubber hose
•
Pliers
•
vacuum gauge (0-1 kPa)
6.1.2 - Precautions
•
Because of the high vacuum condition inside the chiller,
ensure that air never leaks into the chiller during this
work.
•
Handle the vacuum valve carefully so as not to damage it.
•
Solution (absorbent and refrigerant) is sampled at Sv5,
Sv6 and Sv3 in the same manner.
•
Pour the sampled solution into a container.
Refer to figure 8.
6.1.3 - Procedure
•
Confirm that manual purge valves (v1, v2 and v3) are
closed.
•
Remove the flare nut and the bonnet of Sv1, and connect
the attachment to the service valve.
•
Connect the vacuum gauge to Sv2 and open Sv2.
•
Remove the flare nut and the bonnet of Sv4 when
absorbent is sampled, and connect the attachment to the
sampling service valve.
•
Connect the vacuum rubber hose and the sampling
cylinder to the attachment as shown in Figure 33.
•
Run the purge pump and open up v1.
•
Open Sv1 and the vacuum valve.
•
Once the vacuum gauge shows about 0.5 kPa, close the
vacuum valve.
•
Close Sv1 and v1.
•
Remove the vacuum rubber hose from Sv1, and connect
it to the attachment connected to Sv4, as shown in
Figure 33.
•
Open the vacuum valve.
•
Open Sv4.
•
When the sampling cylinder is filled with absorbent, close
Sv4.
•
Close the vacuum valve and remove the vacuum rubber
hose from the attachment on Sv4 .
•
Upon completion of this work, remove the attachment,
and replace the bonnets and flare nut. Also replace the
caps of both service valves after checking their packing.
•
Stop the purge pump.
•
Finally, wash all tools with water.
Summary of Contents for 16NK
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