Page 208 - Pipeline Pigging Technology

Ethylene pipeline cleaning

ETHYLENE PIPELINE CLEANING,
INTEGRITY AND METAL-LOSS

ASSESSMENT

THE ALBERTA Gas Ethylene Company (AGEQ, in co-ordination with
Novacorp International Consulting Inc (Novacorp), successfully performed
an intensive internal cleaning and inspection programme on their ten-year old
180-km (110-mile) ethylene pipeline. Throughput in the pipeline had been
reduced 26% since start-up due to internal polymer build-up. The internal
cleaning and inspection programme was completed (from decommissioning
to recommissioning) in 28 days. The programme resulted in the following:

restoration of the original pipeline capacity;
increased confidence in the pipeline mechanical integrity;
experience in pigging operations and increased understanding of the
internal deposition phenomenon;
a good safety record; and
minimum disturbance to the public.

INTRODUCTION

AGEC operates ethylene manufacturing facilities in central Alberta, Canada.
These two ethylene plants are located 20km east of Red Deer, Alberta, at
Joffre. They supply two customers near Joffre, and the remainder of the
product is shipped 180km by pipeline to other users and cavern storage
facilities near Edmonton. The NPS12 (12-in diameter) steel pipeline was put
into operation in 1979, and typically operates at near 9000kPa (1200psi) and
5°C (40°O- In 1989, after 10 years of operation, AGEC decided to perform an

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