Tuesday, March 13
Favourable reservoir characteristics in the subject reservoir is one of the key requirements for successful gas injection project. Lateral and vertical heterogeneities typically control the gas movement in the reservoir. Characterization of carbonate reservoirs is particularly challenging due to complex post-depositional alterations of rock properties and potential presence of fractures and karsts at varying scales. In this session, advancements and latest techniques in carbonate reservoir characterization will be discussed with a focus on potential impact on gas injection performance and prediction (e.g. modern fracture characterization techniques).
More powerful computing hardware and new software advancements in modeling geologic features and associated fluid flow in complex carbonate reservoirs are becoming available to technical professionals. This session will discuss the latest hardware and software applications and state of the art examples of geologic modeling and simulation applicable to studies of sour gas injection in highly heterogeneous carbonate reservoirs.
Importance of extensive, relevant and timely reservoir surveillance data captured both before and after gas injection commencement cannot be underestimated. An example of pre-injection data that could be very useful to assess interwell connectivity is pressure interference and/or pulse testing. Post injection, data from multiphase flow meters for GOR monitoring and potential H2S tracking capability could be used to detect gas breakthrough. Periodic sampling for compositional changes, tracers, saturation logs and other surveillance methods have helped to calibrate dynamic models and improve our ability to predict future gas injection performance. This session will demonstrate examples of particular surveillance methods that have improved our subsurface understanding.
With a limited number of injection wells and a very high compressor discharge volumes, well Injectivity could become a bottleneck. Establishing and maintaining high well Injectivity is very important to sustain injection, and therefore, production levels at maximum. This session will discuss examples of Injectivity deterioration/degradation over time and proposed mitigations options.
Wednesday, March 14
Selection of injection well location and spacing is a very important decision for establishing effective sweep efficiency and maximizing ultimate recovery. One consideration is that well injectors typically have to be on an approved pattern. Availability of favourable reservoir properties as well as overall reservoir depletion strategy dictates the choice of optimum injector location. This session will discuss key considerations during selection of sour gas injection wells.
Reliable compressor performance is one of the key performance areas of successful sour gas injection projects. There is considerable experience now in Kazakhstan, operating and optimizing performance of compressors which is unique given the high H2S, high pressure and temperature conditions encountered. This is a sharing session for the achievements in improving operability and uptime of sour gas injection compressors.
The fact that H2S is lethal at low concentrations and highly corrosive in the presence of CO2 and/or (salty) water indicates that safety is a main driver in the design and operation of sour gas facilities. This in fact presents many challenges in areas such as data gathering and others. This session will discuss HSE related aspects for sour gas facilities.