Two novel methods are presented, that allow estimating downhole P&T conditions by using wellhead measurements in the Schoonebeek steamflood development: one method allows determining flowing bottomhole pressure (fBHP) and the other bottomhole temperature (fBHT). The resultant estimates are confirmed by fluid level measurements and observation well pressure data.

The fBHP calculation is based on the fact that rod loads are dependent on fluid level. A simple but robust model is presented, which accounts for impact of other parameters (pump speed, watercut, etc.) and allows fine-tuning to match available downhole measurements. The fBHT is estimated by using a simplified analytical wellbore heat loss model that is history matched to wellhead temperatures (WHT) at different well rates.

Both models are applied in the Schoonebeek field steam flood development. Their creation was necessary because operational constraints severely restricted usage of standard surveillance techniques like fluid level measurement and use of downhole gauges on hot producers.

The presented methods allow acquiring robust estimates of downhole P&T regime for flowing producers by using easily accessible SCADA data that is continuously collected at the wellhead. These data are normally used to optimize the rod pump operation and have been recorded since the start of the steamflood (2011–2015); hence, by using simplified rod load models and some statistical analysis it was possible to recover and validate the full fBHP/fBHT history for the hot wells – even for the periods when the fluid level measurements were unavailable or inconsistent.

The models were tested and matched against historical field measurements (fluid level measurements and data from observation wells) and were found to provide sufficient accuracy for use in normal operations (P&T within a few bars / 10 degrees C).

The novelty of the methods is in the ability to use existing wellhead data to come up with robust estimates for downhole P&T conditions on flowing wells. Nowadays continuous SCADA are industry standard; thus, near-continuous fBHP and fBHT monitoring can be achieved without using any additional equipment.

Clear benefits are surveillance cost reduction together with improved well/reservoir management; also, extra data helps improving reservoir model history match quality and forecast accuracy.

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