In this paper, we present for the first time, a classification system for naturally-occurring gas hydrate deposits existing in the permafrost and marine environment. This classification is relatively simple but highlights the salient features of a gas hydrate deposit which are important for their exploration and production such as location, porosity system, gas origin and migration path. We then show how this classification can be used to describe eight well-studied gas hydrate deposits in permafrost and marine environment. Potential implications of this classification are also discussed.
Gas hydrates reservoirs are a type of unconventional reservoir that is an extremely abundant and ubiquitous source of energy. They are also relatively cleaner than most other hydrocarbon sources which makes them an even more attractive source of energy. The potential of this source of energy has, however, not been utilized since very little production has ever taken place from these reservoirs due to their complexity. This research provides an understanding of gas hydrates thermodynamics and reservoir properties in order to assist in properly modelling the hydrate flow in porous media. The research also provides a road map to the current production methods that have been used in pilot tests in order to produce from gas hydrates reservoirs. The production methods explained include depressurization, thermal stimulation, inhibitor injection, combined methods, carbon dioxide injection, and mining. The mechanism of each method is fully explained, and the advantages and disadvantages of each method are also explained. Several case studies worldwide are also discussed to show how each production method has been used to produce from the gas hydrate reservoirs. The results from the case studies are also used to reach conclusions on how each method can be improved upon. To the author’s knowledge, no publication has provided a complete overview on gas hydrates and their production mechanism which makes this research a crucial step in providing an overview on many aspects of gas hydrates reservoirs and their production mechanisms and potential. Understanding the mechanisms to produce from gas hydrate reservoirs is a crucial step in the hydrocarbon industry to allow us to tap into this vast source of energy in the near future.
Today, when most reservoirs have low productivity, the question of whether hydraulic fracturing can be applied to the oil rims becomes very important. During hydraulic fracturing at Novoportovskoe field, the operator was faced with a complex geological model of the reservoir characterized by an absence of strong barriers and minor contrasts in stress between interlayers associated with high risks of breakthrough into the gas zone. An outstanding example of oil rim stimulation and application of new technology was a project in Novoportovskoe field where 30-and 27-stage multistage fracturing operations (MSF) were successfully performed with a shifting ports completion operated by coiled tubing. Currently, oil and gas companies are increasingly demanding technical and technological aspects of the MSF, where the determining factors are the efficiency of operations, the number of stages, the length of the horizontal part of the well, the possibility of refracturing, and ability to open / close sleeves after operation for water and gas shut-off. The experience gained shows the possibilities of modern technologies, where the use of coiled tubing enables meeting the high requirements and also expanding the boundaries of the application. The 30-stage boundary was successfully overcome and allowed to increase the formation coverage by means of more fracturing stages. At the same time, the completion method made it possible to perform MSF without pulling the coiled tubing out of hole and to use all the capabilities and benefits of CT in the case of a screenout (SO). The teamwork between the customer and several of the contractor's product lines enabled successful completion of the integrated project under the difficult geological and climatic conditions of the Novoportovskoe field, which is located beyond the Arctic Circle. An optimized concept of MSF with the use of re-closable full-pass hydraulic fracturing sleeves, operated by a single-trip coiled tubing-conveyed shifting tool was developed and implemented.
With the current increase in demand on hydrocarbons, production from unconventional reservoirs has become extremely high. One of the most abundant, yet still not mass produced from, unconventional reservoirs is gas hydrates. This research investigates the applicability of steam injection in increasing gas recovery from gas hydrate reservoirs, and its impact on water production from gas hydrate reservoirs. The reservoir model was built based on data collected from previous models found in the literature. After specifying all parameters for the reservoir, and the hydrate layer, a systematic study was performed in order to assess the use of steam flooding as the primary hydrate production mechanism. The production methods studied include depressurization as the base case, and then steam injection. The conditions for the steam flooding were kept the same during all runs in order to be able to compare them. Results indicated that the use of the thermal stimulation alone without inhibitor managed to increase recovery, however, the problem of hydrate reformation occurred which caused a cessation of production. Also, water production increased significantly when using steam injection compared to depressurization, mainly due to the rapid hydrate dissociation during steam injection, and also due to the increased volume of water resulting from the injected steam. To the authors’ knowledge, no extensive study has been performed on using steam injection as the primary hydrate production mechanism, and assessing its impact on increasing water production form gas hydrate reservoirs. This research can help in improving real field gas hydrate projects by making the overall project much more economic by increasing hydrocarbon recovery.
Arctic is widely considering as the last world biggest storehouse of natural resources. But its unique nature should always remain the main concern for all the energy projects development in this area. To achieve this development of the Arctic should go along with innovative technologies development. The ambition of this paper is to provide assessment of main Arctic projects on international energy markets development.
Russia always plays an important role on iternational energy markets as one of the major oil and gas producers and exporters since the country entered international enrgy market in the middle of the last century. And this role will remain stable at least till the year 2040 according to current forecasts. BP estimates, that Russia will cover around 5% of the global energy demand by the year 2040. Though, Russia has around 17,4% of world gas reserves (OPEC's estimates its even more - around 24,6% due to the different methodology) and only around 6% in world oil reserves, Russia contributes 17,3% to world gas production and 12,2% to world oil production in 2018, according to BP's Statistical Review of World Energy. Developing of enormous gas and oil reserves was extraordinary challenging for the country due to harsh climate conditions, lack of infrastructure, unsufficient financing and need to develop not only fields but the whole remote areas of the country. Though the country was widely ctitised for its dominancy on the European gas market, in this paper it will be outline that developing of the European gas market was of mutual interest of Russia and European Union and both counterpart became beneficiary of it. This paper focuses on challengies with developing enormous gas reserves as Russia has several mega giant gas fields and its experience can be usefull in developing other mega projects around the world.
Evaluating of VIT performance
Statistics, Finite Element Analysis (FEA), Computational Fluid Dynamics (CFD)
The utilization of Vacuum Insulated Tubing (VIT) is necessitated by the growing oil and gas development in northern regions of the Earth and application of thermal oil recovery methods. Conceptually, VIT consists of two (external and internal) pipes coaxially fixed at the ends, with the annular space filled with thermal insulation including getters (gas absorbers). After the pipes are assembled, air is evacuated from the annular space to create vacuum. Getters are fully activating within vacuumizing. Prior to commercial utilization at Gazprom, the VIT was tested at the Gazprom VNIIGAZ Institute (Russia) on a dedicated thermophysical testing bench. Tests were designed to measure the Coefficient of thermal conductivity (k-factor) of the VIT Vacuum Shield Thermal Insulation. Results obtained during the tests are as follows: with hot air (84…93°C) passing through the tube, the temperature of its external surface remained within the range of 28…35°C, while k-factor was 0.004…0.008 W/(m*K). Gazprom requirements k-factor with max. 0.012 W/(m*K). When VIT successfully passed bench tests, they were approved for utilization in the commercial development of the Bovanenkovskoye field operated by Gazprom. In order to gauge heat flux and effective k-factor of VIT walls at different gas flow rates and fluid temperatures, the design provides for satellite pipes to be installed within the gas well's cement column. At the moment, wellhead soil temperature observations are carried out regularly at VIT-equipped wells. Some gas wells have been monitored for 3 years now. The results of monitoring of 18 well pads (163 wells) the temperature stabilization of the permafrost soil at which is carried out only through the operation of seasonally active cooling systems (without the use of VIT) show temperature increases in the soil along the wellbore. Wells operated with VIT and cooling systems keep freezing temperatures within the cement column throughout the entire annual cycle. For steam injection technologies, may be used theoretically estimation about how temperature of steam decreases from top to bottom of well depending on VIT k-factor and length of VIT string. Such information needs for VIT well design.
Empirical information about VIT utilization
Pilnik, Sergey (Gazpromneft-Yamal) | Dubrovin, Andrey (Weatherford) | Zimoglyad, Mikhail (Gazpromneft-Yamal) | Bulatov, Fuat (Gazpromneft-Yamal) | Burkov, Fedor (Gazpromneft-Yamal) | Abaltusov, Nikolay (Weatherford)
The key opportunity of Novoportovskoye Field is hydrocarbon reserves, which remain undeveloped. In this field, significant oil reserves directly underlie massive gas caps. Economic efficiency in such geological conditions is based on the use of new technologies for the maximum extension of field infrastructure loading.
This paper reviews prerequisites and cases of multilateral well drilling technologies as an efficient EOR method at Novoportovskoye Field. The paper summarizes the results of drilling of nine multilateral wells.
The strategy of multilateral well completion at Novoportovskoye Field increased the level of complexity defined by technology advancement for multi-laterals (TAML). First, a multilateral well with an openhole lateral was drilled. This openhole section collapsed when the well was brought into production at the target drawdown. Therefore, the second stage was to construct a multilateral well with cased main bore and lateral using TAML-1 technology.
A version of TAML-1 technology developed by a Russian manufacturer was adapted and implemented at this stage.
Several sidetracking methods were tested to reduce the rig time and multilateral well construction costs. Application of rotary steerable systems (RSS) for sidetracking instead of conventional rotary assemblies and downhole motors enabled to reduce the average sidetracking time from 70 to 30 hours. The record time of sidetracking using RSS was 16 hours.
The history of Novoportovskoye Field development demonstrates a continuous trend towards increasing horizontal section lengths from 1,000 to 1,500 and 2,000 meters. The cumulative multilateral well drilling experience enabled construction of a well with four laterals with a total length of horizontal sections of 4,411 meters. It was the first well with four laterals in Russia built according to TAML-1 technology.
As compared to conventional horizontal wells, the highest initial incremental oil rates were registered in multilateral wells drilled in the Jurassic Yu2-6 interval and the Cretaceous NP2-3 interval of the Novoportovskaya Formation. Considering that the share of the Yu2-6 interval in the oil reserves of Novoportovskoye Field is 46% and the share of the NP2-3 interval is 17%, the operator decided to increase the share of multilateral wells to develop these intervals.
The project objective for 2018 - 2020 is to increase the number of cased holes, to separate laterals to the maximum possible distance, and to improve the completion level to TAML-4.
Simon, Igor (Science and Technology Center of Gazprom Neft) | Koryabkin, Vitaly (Science and Technology Center of Gazprom Neft) | Semenikhin, Artyom (IBM Science and Technology Center) | Gruzdev, Arseniy (IBM Science and Technology Center)
In this paper, we present a methodology for determining lithological difference at the bottom of the well during drilling operations. Our approach is based on the analysis of mechanical parameters of drilling. These parameters are receiving as real-time time-series data. The central part of the methodology is a model based on the machine learning approach. Our model and the whole methodology can be applied to real drilling cases. The set of parameters that are required for the methodology can be collected from the typical mud logging station.
The main use case for the methodology is an optimization of the geosteering process. The most modern geosteering approaches are based on the LWD data. It is the main restriction of common approaches for the adjustment of the direction of drilling. The problem is that the LWD sensors are placed for a few decimals meters before the bit in a typical Bottom Hole Assembly (BHA) design. As a result, these a few tens of meters are drilling in a "blind window".
The methodology is illustrated on the historical data of drilling of the Novoportovskoe oilfield. At the current stage, the results of the testing show that suggested methodology can correctly classify two out of three cases of changes of lithotypes while drilling.
Olender, Oleg (Gazpromneft-Yamal) | Malyugin, Andrey (Gazpromneft-Yamal) | Fedotov, Vladimir (Gazpromneft-Yamal) | Korepanov, Alexander (Gazpromneft-Yamal) | Asmandiyarov, Rustam (Gazpromneft STC) | Zulkarniev, Rustem (Gazpromneft STC) | Studinsky, Roman (Gazpromneft STC) | Sayfutdinov, Elnar (Gazpromneft STC) | Ivanov, Anton (NOV Completion Tools)
Novoportovskoye Field is classified as large and is characterized by complex geological structure, reservoir development is complicated by bottom water and gas caps. The field is developed by horizontal wells with a horizontal section length of up to 2,000 m and various completion methods: 1. Assemblies with extended screen sections isolated by packers 2. Assemblies with sliding ball-activated hydraulic fracturing collars 3. Internal-flush assemblies with hydraulic fracturing collars (30pcs) activated by a special CTconveyed device. To estimate the efficiency of multistage hydraulic fracturing in horizontal wells, a module has been developed that allows estimating the effect of the primary and repeated fracturing. The module takes into account the increase in the number of frac stages, fracture half-length and width, it allows to estimate the risks of clay barriers breakthrough, evaluate reservoir properties, and select the stimulation option. To select wells for Hz sidetracking and infill drilling, an algorithm for identifying undeveloped reservoir sections was applied to evaluate the efficiency of well interventions and assess the risks in each zone. In the conditions of oil rims, to increase the efficiency of reservoir development using horizontal wells with screen completions, it is recommended to use casing packers in a liner assembly that divide the horizontal borehole into isolated sections. This solution will allow to perform targeted isolation / stimulation of a certain horizontal interval in the process of well operation in case of a decrease in productivity and water/gas breakthrough. As a result, the cost-effective life of a well will be extended and the oil recovery factor of the field will be increased. A twin-packer technology for a targeted stimulation of a certain interval in a horizontal wellbore was tested and successfully implemented by Gazpromneft-Yamal. 2 SPE-191715-18RPTC-MS