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Producing heavy oil from shallow wells using rod pump applications requires careful design considerations especially for down hole components to achieve maximum production rate and maximize the run life. This paper highlights a successful case study of one such heavy oil sucker rod pump well, in the North Kuwait field of Kuwait Oil Company (KOC), where the rods were specially designed to penetrate through the viscous oil and address the pump floating problem to achieve uninterrupted pump operation. Conventionally, as a rule of thumb for the shallow wells, the rod design initially constituted of twenty percent sinker bars and eighty percent sucker rods. This was to add weight on the pump for stability and proper balancing. In the case of this well, with the same design philosophy employed, it was observed that the pump floated over the viscous oil. The maximum pump fillage was observed to be less than fifty percent. Eventually operational changes were made by reducing the speed and operating at maximum stroke length. However this still did not bring any improvement. Hence, specific design modifications were made in the rod string and the pump size to be able to solve the pump floating problem, achieve maximum production rate, and operate at the maximum possible efficiency. Following the design change, it was observed that the pump was now able to penetrate through the viscous crude effectively. This increased the pump fillage to 75% consistently, enhancing the production rate. It was also observed to improve the unit balancing. This well design was considered as part of the pilot in heavy oil project in north Kuwait field. Since the floating pump phenomena is expected in KOC heavy wells, this design would be employed on similar sucker rod operated wells and neighboring wells suffering from the same well conditions. It is expected that by overcoming this operational issue there will be considerable cost savings and production enhancements.

In rod pump applications around the world heavy oil and sand production is believed to be a dangerous combination. This paper highlights a case study of a heavy oil well in the North Kuwait field where sand production was monitored closely to avoid flow line choke and down hole failures. This case study was used as a pilot for the neighboring wells producing from the same reservoir. In case of wells producing heavy oil with considerable sand production and that undergo cyclic steam stimulation the challenge is often at the end of the production cycle. While the oil is thin and has good viscosity the sand settles itself at the bottom. However, with time as the oil gets colder and thereby heavier, it carries the sand along with it to the surface causing plug in the flow line. This is due to the high viscosity of the oil. This is believed to be the end of production period beyond which it would have been impossible to produce any further even after sand cleanup. Certain operational procedures were established to ensure the integrity of the down-hole equipment and to avoid the failures. It has been observed that by effective sand monitoring it was possible to determine the next injection cycle with more precision. This standardized the injection and production cycle. The flow line choke up problems were completely eliminated as the production period would cease as soon as some sand would begin to appear at the surface. It was possible to establish API gravity cutoff for oil production thus avoiding rod and pump failures. This implementation has been undertaken for the entire field and has shown significant operational efficiency. A pilot was conducted to justify the use of sand production as an indication for the next production cycle for heavy oil well under cyclic steam stimulation.

Objective/Scope Integrity of the wells and facilities is planned right from the reservoir development phase. In the pilot phase all the contributing parameters are collected and considered in the design of the production facilities. As the corrosion/erosion is very important aspect to determine the operating condition and the metallurgy of the facilities/completion, due consideration must be given to the technologies helping the infrastructure planning. However, once the production begins, the real time corrosion monitoring is essential as the reservoir produces from multiple zones along with solids during the complete lifecycle. The sand erosion aggravates the corrosion and can cause leaks around the wellheads and areas with changes in cross section. There are several processes such as inhibitor dosage, chemical treatment are performed from the startup and continued throughout the pilot. The paper covers integrated technologies to minimize the risk of corrosion damages by providing predictive analytics for corrosion and erosion impact. This includes chemical injection system, trace detector, non-intrusive corrosion monitoring, sand detector technologies as a holistic solution and best practice for ensuring asset integrity. Methods, Procedures, Process With the given information on the fluid corrosivity, the corrosion inhibitor and its dosing rate gets identified. Continous injection leads to the formation of a thin film on the entire system which need to be protected. However, many times the dosage is not optimized often leading to over injection or under injection of the chemicals. The injection rate is important to be monitored and optimized with a Realtime corrosion monitoring and gauging the impact on the asset integrity. The non-intrusive easy to install Realtime corrosion monitoring probe can provide real time monitoring for all the above requirements and in remote locations inaccessible during inspection A tracer is added to the chemicals to identify the residual through the tracer meter, which is hooked up with the chemical injection system, to optimize the set dosing rate. The corrosion monitoring system is in a corrosion prone location where the highest corrosion rate is expected to optimize the dosage. The sand detector can be considered in case we are producing from unconsolidated sand reservoir. This helps to identify erosion and where more sand is expected. Results, Observations, Conclusions Integrating all these technologies helps optimize the chemical used by around 20% and maximize the lifetime for the integrity by 70%. Also, it predicts potential failures in the system. As the data is stored and accessed from different locations, the organization will have a better control on the full integrity which lead to better design and alternating the corrosion inhibitor without any risk on the integrity. However, the combined technologies will be high CAPEX, but it will save a lot of OPEX on the long run which is demonstrated in the paper and will provide a good historical data for the field development and overall production enhancement

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