Continuous Emission Monitoring System

The requirements of continuous emission monitoring analysers have changed significantly over the last few years due to stringent pollution monitoring and control standards imposed by Environmental agencies. Pressure from the market place also requires the modern CEM system to have a low cost of ownership, which, in effect, means that high reliability must be a design criteria. Yokogawa's CEMS offers fully automatic system solutions for continuous monitoring of emissions. With fast response times, the system is used for process control applications, handling complex control functions.

Yokogawa's unique Sample Handling System design solution helps:

• Eliminates heating of sample line completely
• Retains water soluble anaysers like SO2
• Achieves low final sample dew point (from -40°C to -15°C)
• Accepts high sample flow rate (up to 25L/min) resulting in faster response time
• Corrosion resistance (means minimal maintenance)
• Very few moving parts - Less maintenance
• Low temperature NO2-NO converter ensures no loss of CO from flue gas
• Customised software for report generation

Yokogawa's Non-dispersive Infrared (NDIR) gas analyser Model IR series is capable of conitnuously measuring CO, CO2 and CH4 gases. This low cost rugged analyser is ideal for conitnuous measurement of CO in combustion flue gas.

• Measures any combination of diatomic flue gases like CO, CO2, SO2 and NO etc.
• Unique thermal flow sensor & special IR source provide excellent stability and repeatability.
• Interference compensating detectors & distribution cell ensures no cross interference - Hence high measurement reliability.
• Single point chopper eliminates noise completely.
• Up to 4 components can be measured in the same analyser

Yokogawa's zirconia oxygen analyser for saving energy and environmental protection.

• Our Cell technology operates at the frontiers of innovation: Sulphur resistance, molecular bonded platinum and zirconia guarantee against corrosive elements from flue gases resulting in efficient readings with least maintenance effort and costs.
• Comes with a fully field replaceable probe (cell, heater and thermocouple).
• The PI controlled heater maintains optimum temperature at 750°C ± 1°C. Translating into longer heater life and lower costs.
• Touch panel screen with trending facility, a Yokogawa First!!

Yokogawa introduces a new concept in Hydrogen Purity & Replacement measurement for Generator Cooling application using Gas Density rather than Thermal Conductivity principle. The main features are:

• The innovative cylindrical resonator design enables direct linear measurement of gas density without reliance on thermal conductivity properties.
• The multimode self-oscillation circuit minimizes drift caused by the sensor itself or by oil, mist, dust and moisture sticking to the sensor.
• As the measurement is based on density which is a direct function of pressure and temperature, process fluctuations for both pressure and temperature are monitored and compensated. The result - improved.
• Designed for easy mounting, both explosion-proof and general purpose converters have very low installation and maintenance costs.
• Vibration-proof construction which is stable up to 10g.
• Truly flame-proof version for both sensors & converters.

Yokogawa's Dust Monitor is based on Triboelectric Principle. This principle is approved by US EPA, the global authority. It scores over Optical system based opacity monitors in many ways.

• No dirty windows - The DT400 gives you a clean plant environment and therefore reduced maintenance. Impossible with Opacity Monitors.
• Immune to vibrations - There are no moving parts in the DT400. Alignment is not necessary as there is no sensitivity to vibration or deformation of stack.
• Measurement of white particulate emission - Measurable with the DT400. Not possible with Opacity Monitors.
• Light-weight construction - The DT400 is a mere 2.2 kg (approx).Opacity Monitors can weight between 30-80kg!
• No recurring costs - Opacity Monitors work on incandescent or visible light or laser. These sources need frequent replacement resulting in high maintenance. The DT400 has no replacement costs.