Vitaly Tsybulskyi. Technical Sales Manager Weatherford
"In blowout operations, we burn most of the commercial gas. In other words, we burn our own funds. Unfortunately, this problem cannot be avoided, as most of the wells in Ukraine are at the final stage of operation. The problem of reservoir flooding is very urgent, we cannot be without blowout and technological operations.
What are the risks, operational and financial losses? First of all, we waste the gas that burns in the flare pit. Instead, short-received products could be sold to the end user. In addition, the manufacturer incurs large operating costs. The 24/7 operation mode is failed to comply with, shutdowns and technological operations significantly reduce the productive working time of the well, more human resources are involved in maintenance. Thus, qualified personnel who should be engaged in enhancing production, developing operational intensification and optimization plans is involved in routine technological operations.
The equally negative aspect of blowouts is the environmental impact. The operator company bears reputational risks related to a negative impact on the ecosystem of the region of works.
One of the solutions that Weatherford offers and actively implements in the Ukrainian market is a plunger system for lifting liquids. By nature, it is a pump that is driven by gas. The gas energy that accumulates down the hole is used to push out the plunger you see on the screen. The plunger acts as a piston, pushing out water. The system is controlled automatically, allows one to choose the optimal cycle of well operation, thereby optimizing the operating mode, and reduce operating costs. Maintaining the system requires a minimum number of personnel, it works in semi-automatic mode. In fact, all the gas enters the transportation line for processing and further goes to the final consumer as a commercial product.
While implementing the technology of plunger lifting of liquid in the fields of Ukraine, we found a systematic problem of the quality of tubing. The threaded joints and the shape of pipes are damaged during the twisting process, which creates problems for the free movement of the plunger in the tubing. The problem of tubing quality somewhat limits the use of this system.
There is an alternative solution. A system that does not depend on the quality of tubing and tubing string, which is proposed and actively implemented in the Ukrainian market, is a system of capillary injection of liquid reagents. It is a quarter-inch capillary tube that is landed to the bottomhole with a metering valve that supplies in our case the foaming agent. The foaming agent reacts with the bottomhole liquid and, under the force of the gas, pushes it more efficiently out to the surface. The system does not require workover, that is, there is no need to involve workover machine. Work is performed using the assembly station (see on on the slide). The station is actively involved on the territory of Ukraine. Well work is performed without killing. The assembly, consisting of a metering valve and a capillary tube, is landed in a given interval and held back by a suspension, thereby serving a sealing function. Later, the tube is connected to a mobile metering system, which works offline due to a solar battery, a controller and an automation kit. The reagent, in a given proportion, is fed to the bottomhole, thus foaming the liquid, creating optimal conditions for gas removal.
More comprehensive solution that is offered in the market is an annulus capillary system. In this case, the system is installed during workover or scheduled repair. It actually performs the same functions with a single difference: the tubing string remains completely free, and we can do all the necessary operations to maintain life-activity and explore the well.
If we briefly analyze the proposed three types of artificial lift, then for the purposes of their application they can be defined as systems that resist liquid loading. The systems can be used to control the corrosion of tubing and underground equipment, the deposition of salts, paraffins and any other solid deposits, as well as control the aggressiveness of the environment.
The economic gain is quite obvious. We get additional production due to more efficient lifting of the liquid. We reduce operating costs and extend the life of the well.
In terms of operational planning, if we are talking about a plunger or capillary lift, the system can be implemented in one day in case of prompt decision-making and work experience. If we are talking about more complex systems in the annulus, then planning times coincides with the planning of workover or scheduled maintenance of the well.
It should also be noted that the installation of the systems requires minor changes to the design of the Christmas tree and tubing string. It also depends on the type of production and the type of system we will use. The payback period can be from one to six months.
We may share some results in the Ukrainian market. We installed more than 30 systems over the period 2019-2020. All the wells operate in the mode of minimal maintenance. The number of blowouts was reduced to a minimum. The increase in gas due to more efficient lifting of the liquid saw its peak of 57%. A positive result depends on the performance of the well. Gas savings due to technological operations increased to 23%. Payback period is from one to six months. In terms of economic gain, then on average 294 hours/year per well is reduced for technological or operational costs. We can increase production on average to 580,000 cubic meters of gas per well per year and gain a financial benefit of USD 50 to 100,000 per well per year. It all depends on the initial parameters of the well, production indicators, as well as the existing gas price.
Now let's talk about artificial lift in the context of workover. Today, the thesis is often heard that it is necessary to reduce operating costs and avoid creating additional capital expenditures in order to correct the economic balance and increase profitability, to stay within the budget is of importance.
In the life cycle of the well, there always comes a moment when it is required to carry out some preventive work, an example is the replacement of tubing or more serious workover. Here, two scenarios exist for the owner of the asset. I tried to show them on the slide. The first is workover, and therefore recognition of expenses in the same year, further continuation of operation of the well. Under the second scenario, the customer can install the artificial lift system and thus delay the workover (by experience) for one year or more and incur capital costs in the future (by minimizing the risks of accidents, reducing production due to negative impact on the reservoir, etc.).
To give a household example, just imagine the situation that you have a car, you pay insurance premiums every year in the amount of USD 1,000 and you have to do it annually. But the insurance company can find a tool and offer you to renew the same insurance policy worth USD 100 (part of the basic fee) and do so for two years. Thus, you do not incur capital expenditures this year, you can balance your budget and spend it on other strategic projects to increase production.
Weatherford has extensive experience in artificial lift. It can be said with confidence that our portfolio is one of the most complete among the global companies. As you can see, our geographical representation is quite wide: 63 bases and more than 1,000 employees. For the Ukrainian market, this means that you will receive the highest quality service using the latest technologies in the shortest time".
