SCRDAIHATSU DIESEL

SystemSelective Catalytic Reduction

Original Bypass-IntegratedStructureSpace Saving

The bypass-integrated structure
requires connection of only one duct
between the engine and SCR system.

Patented

The DAIHATSU - DEC Marine SCR System
Engineered to Achieve the Highest Levels ofSpace Saving and Running Cost Reduction
Marine diesel engines installed on ocean-going vessels must be gentle
to the global environment at all times.
Daihatsu SCR system reduces NOx contained in the engine exhaust gas
through chemical reactions, to produce a clean exhaust.
Daihatsu Diesel adopted a patented bypass-integrated structure
and optimized the electronic control and operation devices to enableeasy onboard installation, save installation space and reduce running cost.

Connectionof single
duct to SCR
reactorCatalyst

Aqueous urea
spraying nozzle
Aqueous urea
manufacturing
equipment
Aqueous urea spraying
pump unit

Controller and control
panel

SCR

Controller andcontrol panel

Aqueousurea tank

DAIHATSU DIESEL

SystemSelective Catalytic Reduction
2

Aqueousurea pumpunitCompliance with IMO
NOx Tier III standards

The NOx removal performance of the SCR systemcomplies with the IMO NOx Tier III standards
effective 2016. It clears the ECA (Emission ControlArea) emission regulation.

Reactor(with built-incatalyst)

Statement of Compliance for IMO NOx Tier III

Compact design for easy
onboard installation

Exhaust duct(with built-in mixer)

Exhaust duct(aqueous urea sprayer)

The SCR reactor can be mounted verticallyor horizontally* to enable flexible installationaccording to the engine roomlayout. The aqueous urea nozzle
sprays the reducing agent inan extremely fine mist so thatthe vaporization distance isminimized.
The duct connected to the SCR
reactor has a switching damper,and the bypass duct is built into
the reactor (patented) to eliminate
the need for the installation of aseparate bypass line.

*Horizontal mounting is possible for models up to SCR81B.

Low running cost

The unique aqueous urea nozzle andelectronically controlled auto-operation optimize
the amount of aqueous spraying and maintainNOx below the regulation value at all times.

100%
Load

100％

NOx concentration
before SCR

75％
50％
NOx concentration
after SCR

25％01050%

2030

Urea aqueous
spraying amountAmmonia
concentration
405025%60 minutes

High vibration resistance
The anti-vibration support for the SCR
reactor provides excellent vibration
resistance to minimize the effect of vibrationtransmitted from the hull.

3Catalyst Reduces NOx Contained in the Exhaust Gas into
Harmless Nitrogen and Water
The spraying of aqueous urea into the high-temperature exhaust gas produces ammonia throughhydrolysis. This ammonia reacts with NOx and reduces it into harmless nitrogen and water.

Temperature
sensorService hatch

Catalyst

The catalyst causes achemical reaction between
the ammonia and NOx toeliminate harmful NOx.

Dust blower

Bypass damper

The bypass damper
performs switching
operations automaticallyaccording to the operating
condition of the SCRsystem.
The bypass damper isinstalled immediately
before the SCR reactor toenable the use of only one
existing duct.

■ Mechanism of NOx Reduction❶ Reducing agent (aqueous urea) is hydrolyzed into ammonia

when it contacts the high-temperature exhaust gas.

(NH2)2CO + H2O ▶ 2NH3 + CO2

NH3 Ammonia❷ NOx reacts with ammonia and reduces into harmless N2 and H2O via a catalytic effect.

4NH3 + 4NO + O2 ▶ 4N2 + 6H2O

NH33 Ammonia
NO NitrogenmonoxideO22 Oxygen

N22 Nitrogen
H22O Water

8NH3 + 6NO2 ▶ 7N2 + 12H2O

NH33 Ammonia
NO22 Nitrogendioxide4

N22 Nitrogen
H22O Water

NOx Emission Regulation (ECA) Will Be Applicableto the North Sea and Baltic Sea in the Future
It has been announced that the North Sea and Baltic Sea will be designated as ECA for NOx,and the NOx emission regulation will apply to new ships constructed on or after January 2021.

USA East Coast andWest Coast, Hawaii,Caribbean Sea

North Sea, Baltic Sea
Applicable to ships
constructed on or afterJanuary 1, 2021

Applicable to ships
constructed on or afterJanuary 1, 2016

The Aqueous Urea Solution Generator (AUS)
for Greater Space Saving and Lower Running Cost
Using urea powder and pure water, the Aqueous Urea Solution Generator produces the necessaryamount of aqueous urea when needed, thus eliminating concerns regarding the deterioration ofaqueous urea caused by long storage periods. It supplies aqueous urea of stable quality.
Since the equipment allows the reduction of the urea aqueous tank size, less storage space is required.
Use of urea powder also reduces the procurement cost.
Heating Unit

■ Structure：AUS agitation Line：Produced AUS
transfer line
：Distillate waterline
DTP

Urea powderinlet

M

Heating Unit

FilterM

FTM

Distillatewater inlet
AUS outlet

FilterM

P ： AUS agitation pump

FT ： Flow sensor

DT ： Concentration sensor

M ： Motor Valve

Concentration
Sensor

AUS agitationpump

The pipe, valve, and fittings are made of stainless steel from the urea
solution outlet to the shipyard storage tank.
5A■ Dimensions and Mass of SCR Reactors25B

30B

36B

42B

49B

64B

81B

100B

144B

169B

196B

240B

Amm

1000

1000

1200

1200

1350

B

SCR model

1500

1700

1800

2200

2350

2500

2650

Bmm

1000

1200

1200

1350

1350

1500

1700

1800

2200

2350

2500

2800

H

mm

2100

2240

2300

2380

2500

2650

2750

2950

3350

3500

3800

4050

350A

350A

400A

450A

500A

700A

700A

800A

900A

900A

1100A

1200A

900

1050

1200

1350

1600

2200

2700

3200

4600

5300

6100

7800

D3
Mass (including catalyst)

kg* Dimensions A and B and reactor mass include lagging (option).

SCR model
Aqueous urea
spraying pipe
Mixing pipe

25B

30B

36B

42B

49B

H

■ Dimensions of Piping Parts
64B

81B

100B

144B

169B

196B

240B

L1 mm

3000

3000

2570

2300

2470

2070

2180

2680

2273

2373

2870

2970

D1400A

400A

400A

450A

500A

700A

700A

800A

900A

900A

1100A

1200A

L2 mm

1110

1110

1350

1520

1660A

1960

2200

2480

3070

3340

3610

3900

D2400A

400A

450A

550A

600A

700A

800A

900A

1100A

1200A

1300A

1400A

1070

1070

1200

1330

1300

1300

1580

2010

1890

2030

2450

2610

Bypass damper L3 mm

A

L1

L2Mixing p

B

Aqueous urea spraying pipe

D1H

H

D36

■ SCR Model Selection Table for Auxiliary Engine
Engine output

Engine model0.412-16

30B

0.5

12-16

720/750375~700

900

400~660

6DE-18900

661~860

36B

0.6

12-16

6DE-20900

811~1,090

49B

0.8

12-16

720/750800~1,280

900

1,000~1,516

64B

1.1

12-16

750

1,280~1,750

900

1,500~2,200

100B

1.7

20-26

6DE-28720/750

1,921~2,140

100B

1.7

20-26

6DE-33

720/7502,700~3,600

169B

2.9

20-26

8DE-33

720/750

3,600~4,800

240B

4.1

6DC-32e

720/750

2,300~3,000

144B

8DC-32e

720/750

3,000~4,000

169B

720/750580~800

900

600~810900

811~1,060

720/750

1,200~1,710

720/750

1,711~1,850

720/750

1,460~1,700

8DEL-23

H

25B

kWm
442~530

6DE-23

6DK-20e

6DK-26e
6DK-28eL3

Requiredairpressure Nm3/h (per unit)

1,200

6DE-18Bypassdamper

DustAirblow spray*1

min-1
6DL-16Ae

D3

Utility
SCR
model

Power
supply2.93-phase20-26 440 or 230
VAC,
20-26
50/60 Hz
20-26

0.8

12-16

81B

1.4

12-16

100B

1.7

20-26

81B

1.4

12-16

0.7 ~
1.0MPaG

2.4

42B
49B

720/750

1,701~2,130

100B

1.7

20-26

8DK-28e

720/750

1,915~2,800

144B

2.4

20-26

6DK-36e600

2,950~3,500169B

2.920-26

8DK-36e600

4,400~4,650

196B

3.320-26* Compatible models are added from time to time. For gensets engine models/specifications not listed
in the above table, please contact our company.
* Please inquire separately for propulsion engine models with SCR compatibility.
*1 Even when the SCR system is in non-operational (bypass operation), air supply is still used at a rate of0.1 to 0.3 Nm3/h for the cooling of the spraying nozzle while the engine is running.

ipeD2(Note) Be sure to use an engine fuel with a sulfur content of 0.1% or less whenusing the SCR system.

■ Period Inspection Table for SCR System

Inspection interval Hr (SCR operation time) ○: Inspection ●: Replacement

Component

Item [Description of maintenance]

SCR reactor

Catalyst [Replacement]

Aqueous urea
spray nozzle
Air distributor unit
Aqueous urea
pump unit

Every day500

●Nozzle [Inspection/Cleaning]
3-way valve gland [Inspection/Replacement]

2,000 4,000 8,000 16,000○○

Air flowmeter [Inspection]○

Strainer element [Inspection/Replacement]○

Pump unit [Inspection]○

Sealing liquid surface [Inspection/Replenishment]○●

Stator [Replacement]●

Aqueous urea strainer element [Replacement]●

Aqueous urea
flowrate controlunit

Aqueous urea flowmeter [Disassembly/Inspection/Cleaning]
Gland packing in flow regulating valve [Inspection]○

Bypass damper

Gland packing [Inspection]○○7

www.dhtd.co.jp
Head Office
1-30, Oyodo Naka 1-chome, Kita-ku, Osaka, 531-0076 Japan
TEL: +81-6-6454-2393 FAX: +81-6-6454-2686

Tokyo Office2-10, Nihonbashi-Honcho 2-chome, Chuo-ku, Tokyo, 103-0023 Japan
TEL: +81-3-3279-0827 FAX: +81-3-3245-0359

Moriyama Division
45 Amura-cho, Moriyama-city, Shiga, 524-0035 Japan
TEL: +81-77-583-2551 FAX: +81-77-582-5714

Daihatsu Diesel Himeji Mfg. Co.,Ltd.
12-8, Fuji-cho, Hirohata-ku, Himeji-city, Hyogo, 671-1123 Japan

Daihatsu Diesel (EUROPE) Ltd.
TOG Borough Yards, 13 Dirty Lane, London, SE19PA, UK
TEL: +44-20-4566-5600

Daihatsu Diesel (AMERICA), Inc.
380 N Broadway, Suite 302, Jericho, N.Y. 11753 U.S.A.
TEL: +1-516-822-3483/4 FAX: +1-516-822-3485

Daihatsu Diesel (ASIA PACIFIC) Pte.Ltd.
16 Collyer Quay, Income at Raffles #29-02, Singapore 049318
TEL: +65-6589-9510 FAX: +65-6536-4964

Daihatsu Diesel (SHANGHAI) Co.,Ltd.
Room A-B, Floor 14, Huamin Empire Plaza, No.728, Yanan Rd.(W.),
Shanghai, 200050, China
TEL: +86-21-6225-7876/7 FAX: +86-21-6225-9299• All information contained in this pamphlet is correct at the time of printing,but may be subject to change without notice.

Printed in Japan
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