Fixed system Biogas analysis.

The DGM9 is a modular fixed analysis system designed to provide a continuous measurement of the gases generated by the decomposition of organic waste: CH4, CO2, O2 and H2S.
The DGM9 is specifically approved by DMT (Deutsch Montan Technologie GmbH) for applications such as landfill sites, sewage works, compost preparation units, etc

Principle of Measurement

The DMG9 is a suction based system. In most applications, a Peltier-effect gas treatment device coupled to a mist eliminator is generally used to keep the sample perfectly dry.
Methane and carbon dioxide are measured with dual wavelength infrared cells and oxygen and hydrogen sulphide with a specific electrochemical cell.

Reliable, Accurate and long lasting
The wet gas to be analysed contains highly aggressive halogenated residues which would destroy the measuring means if they were to concentrate.
For this reason, the gas sample must be treated before analysis as follows:
the sample is chilled to 5C, the moisture is condensed on the pyrex heat exchanger, the particles are deposited in the micro-filter and the condensates are evacuated by means of the peristaltic pump.
The dual wavelength infrared cells and the electrochemical cells guarantee the accuracy and long term stability of the measurements.

Detector Module
The detector module contains the gas sensor block, the processor - controlled signal evaluation and a digital display showing the gas concentration. The output signal is analysed via an integrated micro-processor so that a linear output signal of 4-20mA is available to trigger the respective indication card.

You can choose from 4 modules:

• the CO2 infrared module to measure CO2
• the CH4 module to measure CH4
• the O2 module based on electrochemical cell to monitor O2
• the H2S module based on electrochemical cell to monitor H2S

Alarm module

This module interprets the output signal from the detection module and monitors the working order of the assembly.
It controls the two user adjustable alarm thresholds.
The LED's indicate fault and alarm states. Relays connected to potential - free contacts authorise automatic control of external components such as valves, buzzers and warning lights.

Flow control module

This module monitors the working order of the gas sampling pump.
Two operating procedures selectable by key switch are available:

• calibration
• measurement