Updated: July 2002

1. Equipment overview

Environmental pollution by dioxin is a major problem today. Various measures to reduce dioxin emission have been taken to meet the new regulation. For example, improved combustion control of incinerators and dioxin removal by bag-filters, catalysts, or adsorbents is known to be effective to reduce dioxin emission. It is desirable to check the effect of these methods by an online real-time monitor. However, this can take several weeks and costs several thousands of dollars per sample by conventional regular analysis of dioxin.
The CP-2000 Dioxin Precursor Monitor is an online real-time monitor of chlorophenol, which is one of the dioxin precursors (intermediates of dioxin formation). It is known that chlorophenol and dioxin have a high correlation of concentration in flue gas. The CP-2000 can continuously monitor transient emission of chlorophenol, so that the parameters of the incinerator and the combustion conditions can be controlled to reduce the emission of dioxin.

2. Characteristics

1) Highly sensitive analysis up to a few tens of ppt levels of chlorophenols in flue gas.
The CP-2000 can continuously monitor changes in combustion conditions.
2) Online, real-time monitoring (with cycle of less than 1min.)
3) Continuous automatic calibration of concentration. The concentration is automatically calibrated under of the changes in flue gas components and the combustion conditions.
4) Unitized sampling box
The box enables simple flue gas introduction to the monitor.
5) Installing the monitor both indoors and outdoors is acceptable.
6) Self-check, remote maintenance, remote monitoring of system
Reliability and maintenance ability is improved.

3. Performance

(1) System

Fig.1 System

Figure 1 shows a schematic drawing of the monitor. This monitor can be installed indoors or outdoors, at site. It consists of a sampling box that introduces flue gas from an electric precipitator or duct, temperature-controlled piping, an ion source, and a mass analyzer. The flue gas is continuously carried to the monitor and analyzed.

(2) Principle of analysis
Figure 2 shows the principle of analysis of chlorophenols. The flue gas is pumped to the ionization source. The chlorophenols in the flue gas are ionized by atmospheric-pressure chemical-ionization (APCI) using needle electrode corona-discharge. Ionized chlorophenols and other ions are sent to the mass analyzing vacuum area. The concentration of chlorophenols is given by integrating the peak area in the mass spectrum obtained by a three-dimensional quadruple mass spectrometer (3DQMS). Absolute concentration is calibrated by an internal standard.

Fig.2 Principle of analysis

(3) Principal specification
Table 1 shows the major specifications of CP-2000.

Table 1 Principal specifications

4. Application

A monitor for controlling the operation parameters and the combustion conditions of municipal refuse incinerators and industrial waste incinerators.
Other applications:
Support for research and development of dioxin emission reduction technology.
Support for research of the mechanism of dioxin formation.