Online monitoring and characterisation of mineral deposits in petroleum pipelines

Progressive deposition of scales in petroleum pipelines leads to large production losses. Remedial chemical de-scaling operations require the knowledge of the composition and thickness of these deposits to minimise expensive chemical wastage and costly production shutdowns. Although some work has been reported to measure wax and hydrates in gas pipes, there are no on-line techniques to address the problem of scale assessment. In this regard, some feasibility studies have been previously carried out to develop novel techniques, under ideal laboratory conditions. This paper presents an overview of the work carried out in developing novel ultrasonic monitoring techniques and advances towards the development of scale early warning techniques to detect scale nucleation and monitor early stage growth. The work carried out on sonic enhancement of dissolution during chemical de-scaling is also presented. The overall project branches out into three main areas, namely: (1) top-side monitoring of scale deposits, (2) down-hole monitoring and characterisation, and (3) sonic enhancement of scale dissolution