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1
Jochem: The obvious danger here is that you could get a build-up inside the vessel if there's a
blockage further along the pipe.
Katerina: So the vessel needs a safety valve? Jochem: Yes, and maybe some sort of warning
system, as well. It could be something that’s triggered by a differential measurement. So if
there's a high reading in the tank, and a lower one further along, you'd know there was a
blockage somewhere.

2
Katerina: We’ll need a system for monitoring gas consumption.
Jochem: What, a meter on the supply pipe? Katerina: Well, yes, that would measure cumulative
consumption. But we also need to monitor the actual rate of consumption at different points in
time during the reaction cycle. And if we have those two parameters, we can then determine the
frequency of peaks in consumption, which is the third parameter we need.
Jochem: So that's a software issue, then. As long as the cumulative value's being recorded
against the timescale, we can plot the rate of consumption ...
3
Katerina: The reaction that takes place is going to be exothermic. But the amount of heat will
partly depend on how hot the gas is when it enters the vessel.
Jochem: Yes, because that input heat can be adjusted.
Katerina: Exactly. So we'll need a sensor next to the valve to measure the input value, as gas
comes in, and then another to give us an output value. Then, we can work out the optimum input
temperature for the gas.

b Match the words (1-10) from the discussion to the definitions (a-j).
1 input a the best / the most effective/efficient
2 output b how often something happens
3 optimum c the amount of supplies/fuel used
4 differential d the total quantity so far
5 consumption e a specified period
6 cumulative f a value often expressed with per, for example units per hour
7 rate g the exit value, for example at the end of a process
8 cycle h the entry value, for example at the start of a process
9 frequency i the gap between two values
10 timescale j all the steps in a process, from start to finish

c The following specification was written following the conversation. Complete the text
using the words in Exercise 6b.
Vessel B1: Sensor and Measuring System Requirements
Two pressure sensors: one located inside the vessel, and a second situated on the pipe running
downstream, to enable any pressure (1) differential to be detected.
A flow meter to monitor gas (2) . Data will be recorded as a
(3) figure (total usage), and as flow (4) , in
litres per second. Note: Software will be configured to log flow against the
(5) of a system clock, in order to pinpoint peak flow periods
occurring between the start and finish of a given reaction (6) and to assess
the (7) with which they occur.
Two temperature sensors: one at the entry point of the vessel, to measure (8)
temperature, and a second at the outlet point to monitor (9) temperature.
Note: Precise regulation of the entry temperature will be key to obtaining (10)
reaction performance.

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