API MPMS TR 2570:2010 pdf download

API MPMS TR 2570:2010 pdf download.Continuous On-line Measurement of Water Content in Petroleum (Crude Oil and Condensate ).
NOTE 2 The published precision data for water-in-oil laboratory analytical methods show a non-linear relationship between absolute water content and relative percentage repeatability. Therefore the tolerance value used when comparing OWDs and laboratory analysis should be a function of the average water content reported dunng the verification procedure.
7.3.1 Verification by Continuous Automatic Sampler
If verification is by continuous sampling system the performance of any continuous sampling system used for verification of OWDs should meet the requirements of API MPMS Chapter 8.2.
If no dedicated mixing device has been installed, the continuous sampler probe location should comply with the requirements of API MPMS Chapter 8.2 or ISO 3171.
7.3.1.1 Verification should be by companson of a FWA water value reported by the OWD under test with the water content reported for a continuous flow proportional sample taken over the same time penod. The analysis of the proportional sample must only be for water (not to include any sediment).
The duration of any verification trial between the OWD and continuous flow proportional sampler may vary according to specific site operational conditions.
Guidance is given in API MPMS Chapter 8.2 on the design and operational requirements for flow proportional sampling systems.
7.3.1.2 The flow proportional control of the continuous sampler should be by means of an electronic controller deriving its flow signal directly from the total station flow of the measurement system. The station flow signal may be analog or digital. If an analog flow signal is used then the associated DAC (Digital to Analog Converter) and ADC (Analog to Digital Converter) devices will form part of the OWD system secondary components and be calibrated accordingly.
7.3.1.3 The number of comparative tests undertaken between the OWD and continuous sampler should be statistically significant. Guidance on statistical interpretation is given in API MPMS Chapter 13.2.
The data set used for statistical comparison should not include data examples for which the recorded sampler performance does not meet the sampler performance acceptance criteria.
7.3.1.4 If an OWD and continuous sampler are installed in series, all on-going verification of the OWD should be by continuous comparison with the sampler system over each accounting period or batch transfer.
7.3.1.5 If an OWD is intended as the primary, routine water measurement device, on-going verification checks against a continuous sampling system should be undertaken periodically. Typically, the frequency of on-going verification should also depend on batch size or monthly volume.
The frequency of such verification checks will depend on the length of the accounting period or frequency of batch transfers as well as the practical considerations of site location, such as remote and normally unmanned installations. Again, should also depend on monthly volume.
7.3.1.6 Control charts should be used to compare and document the performance of the OWD against the continuous automatic sampler system.
7.3.2 Verification by Online Manual Spot Sample
If verification is by manual spot sampling the design and operation of the sampling system should meet the requirements of API MPMS Chapter 8.1.
If no dedicated mixing device has been installed the sample probe location should comply with the requirements of
ISO 3171.
7.3.2.1 Verification should be by comparison of the average water value recorded by the OWD during the duration of sampling for each manual spot sample.
A minimum of two values should be recorded from the OWD during sampling.
7.3.2.2 The time taken to obtain each manual spot sample after purging the sample system dead volume should be no longer than three minutes.
Sampling should only take place when the OWD indicates that the water-in-oil level is stable.
A minimum of the number of comparative tests undertaken between the OWD and manual spot sampler should be statistically significant. Guidance on statistical interpretation is given in API MPMS Chapter 13.2.
On-going verification checks should consist of a minimum of three comparative tests.
Each comparative test consists of a minimum of two manual spot samples and two sets of OWD readings.
7.3.2.3 The data from comparative tests should be rejected and the test repeated if.