RADIOACTIVE TRACER TECHNIQUE ON HEAT EXCHANGER

OUTLINEINTRODUCTION

RADIO TRACERHEAT EXCHANGER

TYPES OF HEAT EXCHANGERPRINCIPLE OF RADIOTRACER TECHNIQUE ON HEAT

EXCHANGERSCOPE OF RADIOTRACER TECHNIQUERISK INVOVLVEDRADIATION SAFETY ASPECTSSELECTION OF RADIOTRACERADVANTAGESCONCLUSION

What are Heat Exchangers

DAMAGES IN HEAT EXCHANGERS

NDT TECHNIQUES INVOLVE IN INSPECTION OF HEAT EXCHANGER

Radiotracer Technique

Acoustic Emission Test

Eddy Current Testing

Ultrasound Testing

Sampling Testing

Chemical Tracer Testing

PRINCIPLE OF RADIOTRACER TECHNIQUE ON HEAT EXCHANGER

• Radioisotopes is injected as a sharp pulse into the higher pressure process stream entering the heat exchanger.

• The inlet detector mounted at the tube side inlet (high pressure) monitors the injection peak and time.

• The leak detector (output detector) mounted at the shell outlet (low pressure) detects radiotracer infiltrated into the lower pressure from higher pressure side showing the presence of a leak (if any).

• Any leakage throughout the high pressure tube side could be indicated by a subsidiary peak (so called bypass peak ) preceding the main peak.

• The main peak represents the flow pattern of the fluid flowing from inlet to outlet in normal way, while the subsidiary peak represents the leak because it goes in abnormal way by passing the normal flow.

SCOPE OF RADIOTRACER TECHNIQUE

• The procedure shall be

applicable to the inspection

of all types of Heat Exchanger

and Pipeline systems in

industrial process plants

using radiotracer techniques.

The scope of radiotracers is

expanding because it is relatively easy and can

detect faults while the plant is still online.

RISK INVOVLVED USING RADIOTRACER TECHNIQUE ON HEAT EXCHANGER

• Thyroid cancer

• Damages DNA

• Birth defects

• Bone marrow cancer

RADIATION SAFETY ASPECTSAll necessary radiation protection

aspects were taken into account during

all stages of the experiment (radioisotope

production, transportation, injection, etc )

Nobody except PINSTECH personnel

was allowed to stay within 10 meters

diameter around the injection port

during tracer injection till the area

was checked at the end of

experiment.

SELECTION OF RADIOTRACER

Selection of a suitable radiotracer is very important for the success of the leak detection test.

Most of the radiotracers used in industral tracers experiments are gamma emitting tracers. The energy of the gamma radiation should be sufficiently high to penetrate through the wall of pipes or vessels.

SELECTION OF RADIOTRACER

The following parameters should be considered in the selection of a radiotracer.

The tracer should be the same as the fluid being traced.

The half life of the radioisotope should be comparable to the duration of the experiment .

ADVANTAGES

• High Sensitivity

• Quick Analysis

• Availability of wide range of Compatible Radiotracer

• Use for Leak Detection and for Blockage Detection

• Corrosion Monitoring

• Port Management

CONCLUSIONFrom the forgoing it is evident that radiotracer techniques are well established and widely used for detection of blockages and leaks in different systems, residence lime distribution investigation, mixing studies, corrosion measurement, efficient

management of oil wells, and management of ports.

In most of the situation they do not have any equivalent and competing alternatives. High economic benefits are achieved from the application of the radiotracer techniques to leak detection and location.

COMPILED BY

BILAL AHMED

REG # 2012086

Material Sciences And Engineering (Manufacturing)

GIK Institute Of Engineering And Sciences Topi, Pakistan

REFERENCES

• IAEA, 1990, “Guidebook on Radioisotope Tracers in Industry”, TECH. Report Series No 316, Vienna.

• CHARLTON, J.S; (Ed), 1986, “Radioisotope Techniques for Problem-Solving in Industrial Process Plants”.

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