Limited Explosion in Oil Wells
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Improving oil recovery factor
by Dr. Fedin Today we presented our innovative technology "Improving oil recovery factor in oil fields by method Limited Explosion" This technology is based on many sciences achievements, such as geology, geohydrology, geophysics, oil reservoir engineering, rheology, explosion theory and others. OIL RESERVOIR ENGINEERING
"The oil reservoir engineering progress is indebted to simple hypothesis formulation, which allows to receive truth practical-tested results..." ( SYLVAN J. PIRSON Professor of Petroleum Engineering the University of Texas, 1958) The most difficult field Oil Reservoir Engineering knowledge is "Theory of multi-phase fluids filtering into heterogeneous pore space". One of outstanding scientists - founder the Oil Reservoir Engineering - Dr. Sylvan J. Pirson, in last century was declared about science evolution principles. The progress is based on elimination contradictory story as result of elaborated design. OIL PRODUCTION
- By discovery oil reserves
- By developed oil reserves
The world oil consumption was rising impetuous during 20-th century. In addition, it was reached 4 billion ton per annum. Future oil industry development is depending with two basic factors:
- increasing new oil reserves by prospecting jobs
- and additional oil production on development oil field with the help of progressive technologies of oil extraction.
Of course, prospecting (especially on sea shelf) will be perspective in the near future. However, it is a long way and it needs a lot of capital investments. Another way is applying innovative technologies to improving oil recovery factor in developed oil fields. This way is not so long and more inexpensive. All capital investments in those oil fields were done. This way is oil production improving by efficiently using developed oil reserves. Uncovered oil - main production practice problem
This problem solution makes possible to get the better of all countries
Oil recovery ratio:
Bahrain - 27.2%
Libya - 27.7%
Iran - 30.9%
Saudi Arabia - 32.1%
USA - 32.5%
Iraq - 40.8%
Kuwait - 62.5%
Today World Association must expenditure great resources to supporting oil production level by prospecting, exploration and development new oil fields. At that same time, enormous reserves of uncovered oil are remaining at the bowls of unobtainable oil deposits. Necessity of utilization a lot of water is an economic reason of discontinues exploration oil deposits. This problem solution makes possible to receive a great advantage to any country in the World. In a shot space of time this country able to greatly increase its oil production without capital investments. All oil-producing countries has oil reserves to for that. Rebirth of unprofitabe wells by new oil extracting technologies is reserve of advanced develop countries. Oil extraction decrease producing energy
- Decreasing production energy down formation pressure
- Low formation pressure promote water troubles
- Watered oil is a reason of flow production period reduction
- Watered oil reduce production profitability
A reason of low oil recovery factor is decreasing production energy and as affect low well-productivity and oil watering. The main oil producing practice problems are water troubles. Increasing wet oil in well production is a course of limitation flow naturally period. Watering is increase expenditures on oil extraction and reducing profitability. The water-entry problems solution allows to oil production intensification. Fighting with water is useless. New oil-extraction technologies must be directed on quantitative, qualitative and rheological changes filtering fluids characteristics into the stratum. Producing energy amplification allows improve: - Pressure depletion performance of oil reservoir
- Fluid conductivity of well
- Producible oil index
- Oil production profitability
All changes are possible only by energy consumption. In oil producing practice all-important kind of energy is producing energy. There are many methods of producing energy amplification. They are allows to improving: - pressure depletion performance of oil reservoir by increasing formation pressure,
- fluid conductivity of well by increasing fluid pressure gradients of filtering,
- increasing producible oil index by completely oil extraction
- additional, afterproduction oil increasing oil production profitability,
- to crack water-entry problems make ability to prolonging flow production period.
However, all well-known methods are required a lot of energy and equipment investments. Explosives energy most inexpensive and powerful energy source
The most powerful and expensive energy source is explosive energy. Oil engineers have wide experience of explosion application in oil-production industry. At present explosives applying to - In-situ combustion
- Explosion drilling
- Well shooting
- Fracturing by blasting powder
- Inside oil reservoir powerful explosion
The explosive energy is very simple to keeping and transporting. All countries have a great explosives reserve. Destruction energy
 | All well-known explosion methods are directed on stratum destruction. Full explosion energy directed on - dense oil reservoir rock destroying,
- increasing well bore permeability by fracturing,
- increasing viscous-flow permeability by heating,
- thermochemical dewaxing of well.
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But this energy consumption is not effectively, because it directed on changing natural process. And nevertheless it eccepted a lot of supplied power. Another way is using natural energy resources and its amplification by explosion energy. Transforming energy
Limited explosion energy direct on stagnant oil producing zones to: - Change wall-plastering properties of reservoir fluid (transmutably in unsteady conditions)
- Change multiphase fluid filtering properties by increasing oil relative permeability
Our technology is difference from well-known methods. We are determinates natural fluid hydrodynamic properties into the stratum and to use explosion force on its amplification. Technology principle is based on forcing on multi-phase flow characteristics and filtery conditions. The low-power limited explosion energy is directed on stagnant oil producing zones for: - transmuting oil filtering conditions into unstable state and
- changing filtering flow conditions by increasing oil relative permeability.
Well intervals for limiited explosion are selected by formation evaluation and modeling filtering flow directions into the stratum by special algorithm. This algorithm is based on geophysical evidence, field data, fluid rhegoniometry and oil engineering. Limited explosion
 | Limited explosion realize without producing oil wells shutdown: - In drowned well off.
- Opposite perforated intervals
Explosion energy stimulate turbulent flow and sonocavitation in oil reservoirs |
Limited explosion energy is localized into producing intervals through preselected natural conducting guides. The conducting guides are high-permeability beds. Our technology allows creating well-conditions to direction explosive energy into stratum without oil well destruction. Limited explosion realize without stopping oil extraction on oil field and producing oil wells shutdown. Limited explosion executed in drowned well off, opposite perforated intervals. Explosion energy creates in the oil reservoir rock shock wave. These wave stimulate turbulent flow and sonocavitation and hydrocavitation effects in oil reservoirs. Limited explosion has large explosive action distance - more than 1 kilometer. The preference of limited explosion is its low cost - 3 000 $, and high effectivily - more 10 000 barrels additional oil production. Patent
Limited explosion is patented invention. All rights reserved by Soviet Union and Russian Federation patents. There are 10 patents for different oil extracting conditions and producing practices. The patens owner and auhtor is Dr. Fedin. The patents priority is 2003. The patent validity is 2023. Firs patent was reseaved on 1980. We have a great experience of limited explosion application from 1973.
 Physical principles
Explosion theory  | - Explosion energy create shock wave in stratum
- In contraction phasereservoir fluid movement along-track shock wave direction
- In decompression phase reservoir fluid movement inverse shock wave direction
- Bubble pulse create strata pressure pulsation after explosion
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The primary explosion agents are chock wave and bubble pulsation. In contraction phase reservoir fluid moves along-track shock wave direction. In the decompression phase reservoir fluid movement inverse shock wave direction. This reversed stress forced on fluid filtering conditions. At the picture you can see pressure pulsation after explosion in oil well at 2 km depth. Well pressure during explosion was 60 mega Pascal. Hydrostatic pressure in oil well was 20 mega Pascal. Pressure pulsation damp in oil well was 55 mega Pascal. Turbulent flow
 | - Low water-oil displacement efficiency during laminar flow
- Water-oil displacement take place only from bit core pore channel (a)
- Blasting wave change laminar flow into turbulent flow (b)
- Major oil volume involve into formation fluid vortical movement (c)
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The explosion energy augmented flow pressure gradient and stimulated laminar flow into turbulent flow. Water- Oil displacement efficiency is low during laminar flow, because it takes part only from bit core pore channel. This process we can see at picture - a. Blasting wave transmuted laminar flow into turbulent flow. At that conditions more oil volume from pore space involved into the vortical movement. We can see that at picture - b. Oil saturation in the filtering channels increase. The oil relative permeability became higher than water relative permeability. The oil mobility is high and water mobility is low. Well watering bring down. This is we can see on picture -c. Cavitation
 - In decompression phase formation pressure below saturation pressure and oil bubbling (a)
- In compression phase bubbles collapse with hydroblows and heat release (b)
- Substitution of oil for water in pore space
- Oil displaced in filtering channelDisplaced fluid increase oil relative permeability
Next basic effect is cavitation. Formation pressure pulsations in the heterogeneous stratum create cavitation effect conditions. At picture we see watered filtering channel and pore space, full of oil. When filtering conditions are in stable state, water-oil displacement take place only from filtering channels. Filtering conditions became in unstable state after limited explosion. At the decompression phase formation pressure reducing below oil saturation pressure and oil is bubbling. This is showing on picture - a. At compression phase gas bubbles are collapsing with hydraulic blows creation and heat release (picture - b). Oil displaced from pore space into filtering channel. Into pore space take place substitution of oil for water. Water squeezed into pore space. Filtering channel saturated by oil. This is increased oil relative permeability and reduced oil-producing wells watering. Blasting gear
 | Limited explosion executed by: - Certified geophysical equipment for blasting operations -Powder Pressure Generator (PPG)
- Certified logging cable
- Certified detonation cord
- Certified detonator
For limited explosion realization is necessity standard geophysical blasting gear. Limited explosion technology is very simple in execution. All works are accomplished with the certified equipment and serial production explosions in order with "Technical instructions..." and "Oil Companies order documents". We able to train Oil Companies specialists in equipment application and Powder Pressure Generator repetition work. |
Explosive charge data
RU State Certificate 12.2.003.74
| Operation factors | PPG 100M | PPG 150 | PPG 100/50 | | Charge length, mm | 1000 | 500 | 500 | | Charge diameter, mm | 95 | 95 | 52 | | Charge mass, kg | 10 | 5.5 | 1.7 | | Max. Well pressure MPa | 80 | 100 | 80 | | Max. Well temperature °C | 100 | 200 | 100 | | Max. Well deep, m | 3500 | 6000 | 3500 |
Equipment
- Standard certified mechanisms are used for limited explosion execution. There are:
- wire line spooling system for lowing charges in oil well
- perforated intervals locator for perforated intervals detection
- Well template
- blowing preventer if necessary
Job practice
All operations are satisfied the requirements prevention of accidents.
All operations realized by geophysical party.
Work of hand: - casing calipering
- perforated interval detection in preselected well
- trip in hole explosive charges on logging cable
- limited explosion execution by shooting box
To prepare and execution limited explosion is necessary 24 hours.
Limited explosion is safe for oil well, surrounding and environment. We can creating well conditions for explosive energy directing into the stratum without oil well destruction. Limited explosion effects
The limited explosion havs positive influence on oil field.
Limited explosion commercial application allows to:
- improve oil recovery factor at unprofitable oil fields per 10%
- prolong flow naturally period by oil watery reduction
- reduction of cost for oil production per 25%
- increasing oil production per 20%.
Field of knowledge
Limited explosion applying only in the most complicated oil-producing conditions. They are - Oil fields with low oil recovery efficiency
- oil fields with heavy oil and high-viscosity oil
- heterogeneous fractured oil reservoirs
- water-flooded reservoirs on final research stage
- unprofitable oil fields with watery oil
Today there no one technology operated in those conditions. LUKOIL Perm-Carbon Project
LUKOIL Perm-Carbon project is one of the unique in the world. Lukoil Oil Company is pioneer the use of the limited explosion in commercial application.
Last 4 years limited explosion applying to improving recovery factor on the Perm-Carbon oil field Usinsk oil deposit, Russia. The production performance of this oil field is very complicated. This is giant oil field with prospected oil reserves - 5694 million barrels and complicated production history. During 30 exploitation years was extracted only 350 million barrels. Well stock - 1200. Producing practice is pressure depletion. Oil reservoir rock is fractured limestone with porosity 20% and permeability more 1 Darcy. Producing depth is 1500 meters. Today formation pressure is low and oil watered on 70%. One more problem is highly viscous oil - 800 centipoises in stratum conditions. The main method of improving oil recovery factor is steam flooding. Limited explosion allows increase oil production on experimental objects more than 20%. At that same time, oil extraction expenditures downed on 25%. According with explosion results, oil recovery factor improve up to 10%. Changing oil recovery factor was calculated by the oil displacement characteristics.  First experimental limited explosions on Perm-Carbon oil field were operated on pilot object A-17 in October 2001. Object F-17 is watered area. The program aim was evaluation pressure depletion performance of reservoir after limited explosion. Project duration was one month. There were executed 3 limited explosions in oil well. Effect was calculated as difference from last year oil production in October and 2001 October production, after limited explosion. Summary explosion energy was 200 mega joules. Total blasting factor was 50 kg TNT equivalent. Total explosion cost was 11000 $. Additional oil production was 10304 barrels per month.
 Next object was E-1. This object is the most watered oil field area. The water cuttings of well production is more 80%. Producing practice is natural reservoir drive. The project aim was improving oil producing factor and increasing oil production for prolonging profitable exploitation period. Project duration was 18 months. Effect was calculated as difference from fact oil production and rate level. There were executed 4 series of limited explosions in two oil wells simultaneously. Period between explosion series was 4-5 months. Summary explosion blasting factor was 1000 kilograms TNT equivalent. Summary explosive energy was 4000 mega joules. Explosive distance - 1.5 kilometers. Additional oil production - 217175 barrels. Total project cost was 120000$.
Effect control was operated by measurement of water content in the productive wells and measurement oil output. The effect duration was more than 4 months after every limited explosion. Oil watering reduced on 15%. Oil output was improved on 20%. After stopping limited explosion oil production downed on 2001 year level after effect determination. Limited explosions were prolonging profitable exploitation period on 1 year and 6 months.
 Next object was PTV-3 - watered area. Producing practice - steam flooded operation. All production wells were equipped by output recording system. In four oil wells were executed 12 limited explosions during 7 days. Summary blasting factor was 1000 kilograms TNT equivalent. Summary explosive energy was 4000 mega joules. Explosive distance -1 km. Oil watering reduced on 10%. Oil output was doubled. Additional oil production - 198042 barrels. Total project cost - 30000$. Effect calculated as difference between fact oil production and rate level.
Oil recovery factor improving was detected by comparison between rate and fact water-oil displacement characteristics.The comparison period was 2 years. Really, you can see on picture, that oil recovery factor was improved by limited explosions more than 20%. Effect duration - more than 6 months. - Total Additional Oil - 425 521 barrels
- Total Limited Explosions Cost - 161 000 $
- Gross Profit - 12 566 925 $
Project economical value was calculated as total additional oil production (by limited explosion) multiplied on world oil prices in relevant period. During operations at A-17 object world price was 20 $/bbl, at E-1 - 25$/bbl, PTV-3 - 30 $/bbl. Self-supporting method
Limited explosion is self-supporting project.
Start investments only 100 000$.
Cover of start expenditures - 1 month after limited explosion. Additional oil cost price not more 0.4 $/barrel. Best results achieved in fractured oil reservoirs - limestone and dolomite. Additional profit from additional oil production must be invested in unprofitable oil fields rebirth and new oil deposits prospecting (especially on sea shelf). We able to create and training crew of specialists for limited explosion commercial application. There are a lot of productive oil wells stays in oiproducing regions. By limited explosion application oil industry has a good chance to put into production thousands field wells without capital investments. Fractured reservoir
About 40% world oil reserves confined with fractured oil reservoirs. Oil recovery factor from fractured reservoir today less than 25%. Great reserves for oil industry development connected with fractured oil reservoirs. Limited explosion is one of the effective method limestone oil-field developments. Asmari formation one of basic Mesopotamia province oil-bearing deposit
Asmari formation is one of the basic Mesopotamia oil-bearing deposit. It consist of various fractured limestone. Thickness of deposit - 600 meters. Geological age - uppe rOligocene- Miocene. Massive oil pools. This formation is good opportunity for limited explosion applying. Suggested arrangement
- Select pilot object
- Well survey and exploitation data interpretation
- Shothole preparation
- Limited explosion
- Oil-production control
- Additional oil production calculation
- Limited explosion investments
If any oil Company interested in limited explosion method we are ready to mutually beneficial cooperation. We are ready to operate experimental limited explosions on pilot object. We are ready to training Oil Company specialists. We are ready to organize Powder Pressure Generators manufacturing in any country. Patented tehnology in Middle East and USA in common with Oil Company, or with natural persons. We are ready to create in any country the firm for research study and commercial application in other countries. Prime suggested arrangement you can see on picture.
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