Function and design
multi EA 5000
18
EC/OC
Digestion for EC/OC determination is performed in horizontal operation mode. Digestion
is performed in two phases. In the first process phase, the OC content adsorbed on the
filter samples is thermally desorbed in a pure argon flow. The gaseous products are then
re-incinerated in oxygen. In the second process phase, the remaining EC proportion in
pure oxygen is converted completely to CO
2
.
The filter samples are transferred to the combustion furnace via the ABD and a special
feed program.
4.1.1.3 Measuring gas dryer
After leaving the combustion tube, the mixture is dried before it is transferred to the de-
tectors.
Parameter
Method
TS, TN, TC, EC/OC
Membrane dryer (in the basic module)
TX, AOX, EOX
Concentrated sulfuric acid (in the Cl module)
TOC, NPOC, TIC
Condensation through Peltier cooling (in the TOC module)
4.1.2
Design of the basic module
4.1.2.1 Main components
Main components of the basic
module
The multi EA 5000 basic module contains the following main components:
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Electronics/internal device control
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Gas supply
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Combustion system
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Measuring gas transfer
All basic module components that must be operated or maintained by the user can be
accessed via the 2 doors on the front side or via the removable side panels.
Electrical connection and gas connections) and the interfaces for connecting the system
components are on the rear of the device.
The basic module is available in 3 versions with different operation modes (installation
position of the furnace).
Double furnace device
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Vertical and horizontal operating mode possible
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Opening with maintenance flaps at the right-hand side panel
Vertical device
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Furnace in vertical installation position
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Right side panel closed