Light Scattering
Real Time
Dust Density Monitor System

High sensitivity
Durable and reliable
Ultra low maintenance
Simple installation

URL: http://www.tanaka-e-lab.com
Contact: office@tanaka-e-lab.com

The dust contained in flue gas can cause environmental pollutions and health issues,Compliance and CSR andreducing the dust emitted from a plant/factory is global demand. In many coun-tries the governments enforce air pollution law. Tanaka Electric Lab. dust monitor system helps to run a plant/factory
more cleanly and efficiently and to establish corporative compliance and CSR (Corporate Social Responsibility).
Tanaka Electric Laboratory DDM-fC high performance real-time
DDM-f C Dust Monitor System
dust monitor system is designed for the harsh industrial environment such as high temperature (820 ˚C), high pressure (246 kPa), high humid , andMain Control System
highly electrically charged exhaust gas. It can measure dust density up to 1 mg/Nm3
as regulated by the Air Pollution Control Law. It is designed both for standalone
Purge Air Systemand for unattended automatic CEMS (continuous emission monitoring). It is easy
to be integrated in DCS (Distributed Control System). DDM-fC is an excellent
product for a new installation or replacing unstable existing dust monitor system. The
DDM-f C is composed with an optical detector, fiber cables, main control system,and purge air system. The detector uses light scattering method to detect the dust
density of exhaust gas inside of a stack and has unique design to achieve accurate, reliable, and low maintenance operation. The microprocessor controlled main control
box analyzes the data from the detector and dispatches alarm signals to the DCS tocontrol the whole factory or to the dust control system such as bag filters and ESPDetector(Electrostatic Precipitator) to avoid accidental air pollution or to control the system
Optical Fiber Cable
to lower the operational cost. The data can be transmitted to DCS and stored andused for data log and future analysis.

Tanaka Electric Laboratory Light Scattering Detector
The Tanaka Electric Lab. light scattering detector provides
reliable monitoring in the harsh conditions such as highlyLight Source
electrically charged gas, high humidity gas, and variablevelocity of gas. Its dust detection area is 3 dimensional andElectrodeDDM detection area
Electrodelarge; it covers large area inside of a stack and the detector
Optical penetration
has an excellent sensitivity. The light scattering method
uses optical sensor and provides excellent noise resistance.
Its unique detector design and the integrated purge air
system makes the detector almost maintenance free. In adThe integrated Purge air
Optical penetration dition, the installation of the detector is very simple as well.
system keeps the optical
The electrode method detector is theoretically sensitive, butsensor always clean
Optical Detector
Flow of light emitted the output may be noisy and unreliable. Its detection area isvery small, and the detection may not be accurate. The seninto duct
To main control box
sitivity of the optical penetration method detectors depends
on the product. The detection area is long but narrow. The
Sample Data and Comparison
installation and maintenance are difficult.
Cross Section of the Detection Areas
DDM

Stack/Duct

T.E.L. Light Scattering method vs opacity method
Dust Density

Dust Density

T.E.L. Light Scattering method vs electrode method

DDMElectrodeTimeThe electrode detector could not detect the dust
DDM detected. The signal from the DDM
detector is stable whereas the signal from theelectrode detector is noisy. An electrode method
detector easily picks up noises, and its sensitivity
needs to be set low.

DDM

Optical penetration
TimeDDM dust detector detected the dust the elect rode
method and optical penetration method detectors did
not detect.

The DDM detector and optical penetration
detector sensitivities are resemble. However,
the optical penetration detector’s detection
area is smaller and could not detect the dust
the DDM detector could.

Simple and Easy Installation
Purge Air System Box
It can be installed anywhere and provides
oil and humid free clean air to the detector. The purge air keeps the optical sensor
always clean.

Main Control Box

Detector

The detector body can be easily
installed on stack without any adjustment.

It can be installed anywhere and can beisolated from high heat and static magnetic
field from stack for maximum accuracy
and reliability. The dust detector sensors
integrated with its control circuit is easy tobe installed and may be cheaper, but thesesensors can be affected by high heat andstatic electricity, and may not be reliable
and have shorter life time.

The installation of the DDM-fC is simple
and costs you less. To install the detector
you need just one hall on a stack and minimal work space.
Installing optical penetration dust monitor
systems needs another hall on the otherside of the stack; it is more difficult; youneed more time, work space, efforts, andmoney to install it.

Benefits

Simple and Easy MaintenanceCalibrator
The calibrator issimple and portable. It is easy to becarried and used
for regular maintenance.
DDM-fC can be calibrated, maintained, or fixed while aplant is running, and exhaust gas is still running. It does not
scarify productivity. Most of dust monitor systems needs aplant to be shut down for maintenance.

Tanaka Electric Laboratory dust monitor systems do not only
help to reduce air pollution and to establish corporative compliance and CSR, but also provide other benefits, such as:•••

Improve plant’s productivity
Reduce ESP running cost
Improve plant equipment life time

In addition, there are more benefits:••

Reduce initial installation time and cost
Reduce maintenance time and cost

Reliable Continuous Monitoring
Clogged bag filter happened

Clogged bag filter is fixed
Note:

Dust Density

The right graphis magnified
10x because thesignal is too small
to be visually examined withoutmagnified.

TimeAbnormalTime
normalnormal

DDM-f C was installed at at the exit duct of a cement mill bag filter, continuously monitored dust, and detected an excess of the dust unable to be visually
identified as shown in the right graph. It led to discover a clogged bag filter and afaulty shaking damper, and fix the problem as shown in the left graph.

Applications/Usages:
••
••••
•
•
•

FGD of coal/oil electric power plant
Iron works
Paper mill
Waste garbage incinerator
General boiler
Biomass boiler
Cement plant
Sludge incinerator
Aluminum smelting furnace

Control room

1DDM-fC

Control

1box

Heat exchanger

CB
1
2
3
Auxiliarypower
FG

Power

Duct or chimney

supply board

DPM

34+

5
63-SV3910

Alarm 1 output(Power supply failure)

1112

Alarm 2 output(Lamp failure Motor rotaion failure)1314

2M～ 5M
PT1/4 female

Dry pump

SV2+-Pump built-in typeHeater temp,cont,box

SV1

78Auto zero adj.
contact output

Optical fiber cable(Transmission)

Detector+-3

Optical fiber cable(Receiving)

1Cable234Heater 4

2M～ 5M

Heater 5

Gas flow

Thermostat 6R

Thermostat 78RS-232C

4FAN

Ｐ
Customer construction

Light receiving unit+

Signal processing board with CPU

Dust density output signal(DC4～ 20mA)

122

Motor boxwith lamp

24CB2Alarm 9CB1
1Power supply AC220V,50/60Hz,1.5kVA

AC220V IN

2F.G

3FG

AC220V

P.0T

Alarm 3 output(Pump failure)

AC100V

S.010
AC100V OUT 11

5Specifications

F.GBName2008 08 20segatanaka

Checked2008 08 26tanaka

ELECTRIC LABORATORY CO.,LTD.

C

Dust density meter composition figureTitle

Revisions(1) Structure Wall mount outdoor installation type

Detector

DataDrawn(1) Demention 260 x 125 mm

DE

Ref. Dwg.No.

FG

Control box (Type : DDM- fC)

A512F

ＴＥ０７０１－１２６GﾌｧｲﾙNo.
TAN-009

G(2) Principle 90 degree back ward light scattering method(2) Weight Approx. 5kg(3) Light source halogen light(3) Material Stainless steel (SUS304)(4) Measurement range 0 – 500 mg/Nm3 relative density output (range is variable)(4) Cartridge heater is equipped in order to prevent that the detector’s silica glass becomes cloudy
with dew condensation by the moisture in purge air.

(5) External output DC 4-20mA Isolated output RS-232C(6) Display Digital panel meter of 0 - 100%
(7) Alarm / failure output(8) Calibration: Zero point adjustment , .Automatic / manual change selection ; Span adjustment
Optical fiber cables are connected to calibrator. Span adjustment with manual operation.
(9) Power supply AC100V±10% (50Hz/ 60Hz), 4A from purge air system box.
(10) Operating temperature -10 ˚C ~ +50 ˚C(5) Attachment 200 mm x 65 mm rectangle hole is opened and attached to the duct.
Please give the flange of an attachment part as construction side preparation. The packing between flange-detector is standard appending.
(6) Connection of purge air Female screw of PT 1/4 (cheese union)
Purge air system box(1) Installation restrictions(11) Demention 500 x 670 x 270mm

This unit is able to use in case of that process gas pressure is of the same grade as atmosphericpressure or when it is minus pressure(12) Weight Approx. 45kg

(2) Air flow Approx. 100 l/min(13) Finish painting color Munsel 5Y7/1 G=40

(3) Alarm / failure output air flow stop alarm by pump failure

Optical fiber cable set(4) Power supply AC220V±10% (50Hz/ 60Hz), Capacity 1KVA

(1) Diameter of bundle / Length 4 Ø x 4m (standard)(5) Operating temperature -10 ˚C ~ +50 ˚C(6) Demention 530 mm x 504 mm x 322mm(7) Weight Approx. 35kg

Tanaka Electric Laboratory Co., Ltd.
30-10 Kyodo
3-Chome, Setagaya-ku
Tokyo, 156-0052
Japan
Tel: +81-3-3425-2381 Fax: +81-3-3425-2373
URL: http://www.tanaka-e-lab.com
Contact: office@tanaka-e-lab.com