Gas well production enhancement on the application of innovative structural and thermal insulation nano-coatings

Abstract

At the late stage of gas condensate fields’ exploitation deterioration of hydraulic and gas-dynamic efficiency of jointing flowline pipe lifts and gas collectors leads to the decrease in total flow rates in pattern wells. There are many technical ways to improve a hydraulic efficiency of complicated gas collecting systems in gas condensate fields.

As for the thin coatings with specific thermo-physical, geometrical and structural properties, there is an opportunity to have more simple solutions to optimize hydraulic efficiency of pipe system and particular pipeline sections. The most popular methods of    field experience include smooth, turbulence-insulating and turbulizing coatings.

The fact to be focused on has become the result of calculations - a significant increase in computational and theoretical well production in complex application of special (two or three) coatings in comparison with separate coatings applied.

The base application object is averaged well in Mashevsky field in Poltava region in Ukraine. The general description of the field is following: the average depth of productive horizons is up to 4 km; the length of particular gathering lines up to 2.5 km; the used FCP diameter- 63 mm; the reservoir temperature - 70-80 degrees Celsius and wellhead pressure-s 1-3 MPa. The wells work quite steadily with the consequent pressure reduction at the wellhead and in the layer.

Simplified modelling is based on known equations by Darcy, Bernoulli, Adam, Weymouth, Shukhov and Reynolds. The basic equations were taken in a non-linear form with proven simplifications in field experience that significantly reduced the computing time and made it possible to solve problems in a general setting. In this case the use of three main surfaces is considered: smooth, heat-insulating and turbulizing. Most parameters and initial data are typical for Ukrainian deposits with an average value of stocks.

Nonlinear equations systems solution given by a mathematical model of non-isothermal lifting in condensate wells is done by using advanced algorithmic techniques in Mathcad program, by rank-Kut 4th order with the addition developed by the authors of the initial and boundary conditions in accordance with the physical sense.

Downhole lifting studies were made using developed mathematical models by objects of Mashevsky development, which showed a good value for the simulation adequacy and close agreement between calculated and measured thermometer, manometric and flow-measuring parameters.