Page 40 - Handbook Of Multiphase Flow Assurance

CHAPTER
2

Initial diagnosis and solution of flow

assurance production problems in

operations

OUTLINE

Field or laboratory tests for initial solid Field analysis 40
samples identification 40 Laboratory analysis 40
Field laboratory initial tests for solid Typical blockage remediation plan 42
samples identification 40

An operator may interpret the telltale signs of flow assurance problems to help identify
them first and then select the best solution. We can attribute characteristics of flow assurance
issues to the two parameters usually measurable in the field: pressure and time.
Pressure measurement is commonly available in the field production systems. Operations
usually have a limited instrumentation installed on production systems, but most systems
have the pressure measured at the tree upstream and downstream of the choke, and some
have gauges downhole in a well which measure pressure in real time or as a retrievable
recorder. Some chemical skids may have a chart recorder. Any additional available measure-
ments such as temperature, water cut, flow rate, ultrasonic or dielectric signal will help verify
whether the initial identification of flow assurance issues makes physical sense.
Time is the other parameter commonly measurable in the field. It may be possible to tell
which problem is likely taking place by evaluating the time it took for the readings to change.
Both time and pressure need to be evaluated together.
Hydrate plugs can develop as quickly as in tens of minutes, or as slowly as in days. Scale
restriction may form as quickly as in 1 day, or build over the period of weeks. This distinction
of time can be used to help differentiate between different types of blockages when condi-
tions for several different blockage types are present in the production system simultaneously.
Table 2.1 suggests a preliminary list of possible causes for a pressure change in a flowing
system, depending on how quickly that change occurred.

Handbook of Multiphase Flow Assurance 35 © 2019 Elsevier Inc. All rights reserved.
https://doi.org/10.1016/B978-0-12-813062-9.00002-6