We will start shortly…

Leakage Detection for Toxic Chemicals

Presented by: Riccardo Belli – PLM Distributed Sensing

Web SeminarWeb Seminar

• You should hear my voice through your PC speaker / headset

• You can ask questions using the “Questions” panel on the right of your screen. We will answer:– In the “Questions” Panel– At the end of the presentation– By email

• Later this week you will receive link to:– Presentation in PowerPoint, PDF and with narration– Datasheets

ContentsContents

• Context – motivations• Fiber optic sensors Technology• Leakage detection• Application examples• System reliability – Level of confidence• Questions and answers

Context – motivationsfor leakage detection

Context

1966. Feyzin (France)- Explosion of 2 propane

storage tanks-18 deaths and 84 injured

1976. Seveso (Italy)- Toxic cloud carrying dioxine

- 4 villages covered by the cloud

- About 37 000 people impacted

(no immediate deaths)

Historical dates of industrial accidents

Historical dates of industrial accidents1984. Bhopal (India)

- Explosion of 40 tons of toxic gas (isocyanate of méthyl)- 8 000 deaths the first night- 16 000 and 30 000 deaths

2001. Toulouse (France)

- Explosion of the fertilizer plant AZF- 30 deaths- 3 000 injured- Destruction of infrastructures and housings

Historical dates of industrial accidents

2010. Ajka Alumina (Hungary)

- Release of 600 000 tons of red muds (arsenic, mercury and lead) spilled from open air storage tanks- 9 deaths and 200 injured- Critical environnemental damage (soils and rivers)

Reglementation• The reglementation (SEVESO II) focus on the prevention

of major accidents on industrial sites such as fire, explosion or release of toxic gases.

• In this framework, the industrial site owner builds up a risk analysis in order to identify all the accidents which can occur, to evaluate their probability, gravity, and cinetic and to implement the appropriate prevention measures.

• The leakage detection acts as a safety barrier allowing to reduce the risks at source.

Technology of Distributed Sensors

FO Distributed Technology

www.smartec.ch

T, ε T, ε

Scattering of lightScattering medium

Laser, lo

Optical Scattering in Silica FibersOptical Scattering in Silica Fibers

www.smartec.ch

T1

Reading Unit

Distributed Sensor0m

1m 100m

1000m

30km

T1

T2

T2

Position [m]

Tem

p. [°

C]

Distributed sensingDistributed sensing

www.smartec.ch

Single fiber optic sensor (sensing cable) Every segment (1 - 2 meter long) of sensing cable

replaces discrete temperature sensor Complete temperature profile over the entire cable

obtained by single scan (10 seconds) Provides for location of the temperature event (1 – 2

meter accuracy)

Distributed sensingDistributed sensing

www.smartec.ch

Advantages of Fiber Optic Sensors Advantages of Fiber Optic Sensors

EM fields immunity Installable in explosive areas Small size and lightweight, easy to install, low

maintenance Durability and reliability of sensors High sensitivity to temperature (0.1°C) Permanent monitoring Long measurement range (several kilometers) Quick response time (10 seconds) Software adaptable to various operation conditions,

climatic conditions Cost-effective

www.smartec.ch

Leakage detection principle : Temperature anomalies analysis

Working principle

www.smartec.ch

Leakage DetectionLeakage Detection

Temperature profiling along pipelines/storages Leakage detection through temperature anomalies

analysis at the leakage point· Change of the cable temperature due to liquefied gas

relaxation· Cooling due to gas expansion· Change of the cable temperature due to liquid spilling

High sensitivity for the detection of micro-leakages Identification of the leakage location with 1 – 2 m

resolution.

www.smartec.ch

Liquefied gas (Ammoniac, CO2, Ethylene…)

High pressure gas (natural gas)

leak

temperature effects

warming

coolingOil or hot liquid

pipelines

T/ °C

time

T/ °C

time

Pipeline

Leakage DetectionLeakage Detection

www.smartec.ch

Sensing fibre cable

Leakage is detected by the temperature difference induced by the presence of the released fluid on the sensing cable (temperature of the liquid different from the ambient cable temperature)

Tem

pera

ture

Position

Leakage

Leakage Detection - liquidLeakage Detection - liquid

www.smartec.ch

Sensing fibre cable

Leakage is detected by the temperature drop of the gas induced by the decompression of the leaking gas caused by the Joule-Thompson effect (pressure relaxation to atmospheric pressure cooling)

Tem

pera

ture

Position

Leakage

Leakage Detection - gasLeakage Detection - gas

www.smartec.ch

Temperature Sensor cable

• Range of monitoring up to dozens of kilometers

• Temperature accuracy: 0.1° C• Spatial Resolution: 1 meter• Response time: 10 seconds• Permanent monitoring• Leakage detection software• Remote monitoring via Ethernet

• Distributed temperature sensor (cable)• Rugged, watertight, corrosion resistant• Low/High temperature and shock

resistant• Insensitive to EM fields• Easy and rapid to install

Reading unit

System componentsSystem components

www.smartec.ch

N° of sensors: up to 4 Multi Mode optical fibres per cableCross-section: 3.8 mm with PA sheathCable weight: 22 kg/km with PA sheathTemperature range: -55°C to +85°C in long-term

-65°C to +300°C in short-term-60°C to +85°C storage

Mechanically reinforced temperature cable

Optical fibres

Stainless steel wires

Stainless steel loose tube

Sheath

Temperature sensorsTemperature sensors

www.smartec.ch

Alarms can be triggered on the reading unit or on the database User can set various actions to communicate an alarm: ex. email,

relay control, text message, etc.

Warning!!! – Temperature event at 430m

E-mail SMS Relay/Modbus Network

Alarm softwareAlarm software

www.smartec.ch

Alarms triggers if absolute temperature is exceeded : suitable for situation in very stable environment

Ambient Temperature very stable

Alarm triggered if pipeline leaks and temperature drops

Time

Temperature at point (x)

Temperature at time (t)

Length along cableLeak triggers alarm

Absolute temperature - alarmAbsolute temperature - alarm

www.smartec.ch

• Alarms triggers if rate of change is exceeded : suitable for dynamic but predictable environment

Typical temperature drop = 0.05 °C/min

Max normal temperature = 40°C

Absolute temperature alarm set to 60°C

10

40

Night time temp

Time

Temperature at time t

Max day temperature

24 hours

Rate of change - alarmRate of change - alarm

www.smartec.ch

DamsDikes

DiView graphical user interfaceDiView graphical user interface

www.smartec.ch

Application Examples

Application examples

www.smartec.ch

Leakage detection of an ammonia rack pipeline in a fertilizer production plant

Yara Italy – Norwegian world leading supplier of plant nutrients in the form of mineral fertilizer

Ammonia pipeline monitoring

www.smartec.ch

2.200 meters of ammonia rack pipeline Material: carbon steel Diameter: 2” & 4” Working pressure: 16,5 bar Design pressure: 20 bar at max 50°C The ammonia inside the pipeline is in

liquefied state. In case of leakage, the ammonia goes out at atmospheric pressure both in liquid and gas states at approximately - 30° C

The aim of the monitoring is to detect leakages by continuous temperature monitoring

Rack pipeline outline

www.smartec.ch

DiTemp DTS-SR inside the Control Room

2 X

JB with splice

Main JB

2 X

JB with splice

1 X

Junction Box

1 X

Installation layout

www.smartec.ch

LINE ALARM N° DETAILSFROM TO SET

(meter (meter) °C

GREEN LINE TKA 100/1

1 Alarm at low temperature 120 300 -5

2 Alarm at low temperature 300 565 -5

3 Alarm delta T previous measure 120 300 -12

4 Alarm delta T previous measure 300 565 -12

BLUE LINE TKA 100/2

5 Alarm at low temperature 1'020 1'300 -5

6 Alarm at low temperature 1'300 1'670 -5

7 Alarm delta T previous measure 1'020 1'300 -12

8 Alarm delta T previous measure 1'300 1'670 -12

RED LINE TKA 100/3

9 Alarm at low temperature 2'325 2'500 -5

10 Alarm at low temperature 2'500 2'800 -5

11 Alarm at low temperature 2'800 3'150 -5

12 Alarm at low temperature 3'150 3'420 -5

13 Alarm delta T previous measure 2'325 2'500 -12

14 Alarm delta T previous measure 2'500 2'800 -12

15 Alarm delta T previous measure 2'800 3'150 -12

16 Alarm delta T previous measure 3'150 3'420 -12

Fault TKA 100 Alarm for faulty system

Alarm threshold

www.smartec.ch

Temperature response over the monitored part of the pipeline measured during the setup of the system

0

5

10

15

20

25

30

0 500 1000 1500 2000 2500 3000 3500 4000

Length (m)

Tem

per

atu

re (

deg

C)

control room

blue fibre line red fibre line

green fibre line

Temperature distribution

www.smartec.ch

Leakage simulation on ammonia rack in France

From storage tank to truck and wagon loading arms : 900 meters

Material: carbon steel Diameter: 6” Working pressure: 8 bar Outside temperature : 0°C Nominal flow : 100 tons / hour Optical cable located below the pipeline

Ammonia pipeline monitoring

www.smartec.ch

2 tests were achieved by spilling ammonia on the pipeline :

• Test 1 : 1 kg of ammoniac over 1 meter over 1 minute (equivalent to 0.06 % of the nominal flow)

• Test 2 : 0.5 kg of ammonia over 0.5 meter over 1 minute (equivalent to 0.03 % of the nominal flow)

Leakage simulation

www.smartec.ch

Detection of micro leakages (less than 0.1 % of the flow), attenuation of transient phenoma (pumps)

Test

1

Test

2

pum

ps s

tart

Threshold for leakage detection

Data after treatment by suitable algorithm

Test results

www.smartec.ch

System reliabilityConfidence

System reliability

www.smartec.ch

If red sensing cable is broken the DTS will still measure either side of the break. The blue sensing cable will still measure the entire pipeline length.

If blue sensing cable breaks the DTS will still measure either side of the break

If one DTS fails, the redundant DTS stills operates

DTS DTS

Redundancy

www.smartec.ch

• Based on the « proven by experience » approach• A combination of redundant architecture & tests allow a SIL

equivalence:– Redundancy: two/three interrogators and cables– Voting systems (1oo2 or 2oo3)– Positive security– Regular test on the line (ex : with CO2 bottle)– Regular maintenance

SIL equivalence

www.smartec.ch

Distributed Fiber Optic sensing is a novel, but well proven technology to detect toxic chemicals leakages in industrial sites (SEVESO classified)

It offers unprecedented sensitivity to detect very small leaks in a few seconds and allows the localization of the leak with meter accuracy, which cannot be detected by conventional techniques

Appropriate architecture and testing program guarantee a high level of confidence to the system

The deployment of such system has been carried out successfully in a number of reference and qualification projects worldwide

General conclusions

www.smartec.ch

Thank you!Any question?

Safety first

Conclusions – Leakage detection