Shale gas, hydraulic fracturing and other "animals"

I develop the enterprises of oil and gas industry for the last seven years. I started with the financial and personnel reorganization, have the experience of establishment of drilling companies, currently develop oil and gas service companies. We are just those guys who drill, repair and pump in-pump out unlike producing companies which hold licenses. I think that experts being amused enough by nonsense regarding shale gas and hydraulic fracturing will approve some rows of common sense and the simple readers will raise their educational level after reading of some words about the "magic with subsequent disclosure".

The First Myth. Shale gas. Unconventional hydrocarbons.

No "shale gas" exists for specialists. This term was specially invented and implemented for state and private investors around the world for gathering money on exploration and exploitation of oil and gas fields in tight reservoirs. It is in a word, if to say more, it will sound like this:

Oil, gas and gas condensate are not contained in capacities or caves in the ground -  they are contained and flow into tiny pores of rocks - if a rock has connecting emptiness, it means that this rock has reservoir properties. If you look with the naked eye on a rock, you will see neither oil, no gas or condensate - it's not a sponge or pumice, it is an ordinary-looking stone. I hope you have ever seen water is seeping through a stone on a rocky fault – it is the same. It is impossible to see these pores or cracks without a microscope but they are. Tight collector is a rock with a little quantity of microcracks and microemptiness, which weakly connect with each other. For example, we can see it in shales. While gas or oil are not called and are not exclusively shale. The origin of this gas is still unknown - it is just known that it’s a mixture of methane and some other gases. Some scientists believe that this gas (or oil) was created due to decomposition of organic matter, others, like Mendeleev, believe that it is water and iron that raise up the crust faults from the Earth's core and form hydrocarbons, reacting with rocks. As for me, the astronomer-amateur, I believe that oil and gas are present in composition and structure of the Earth initially, this is proved by an existence of all the planets-giants and their satellites. This theory, at least, explains the reason of oil and gas formation under the granite slabs in Vietnam and other countries, where the sediments left high above. Thus, a copyright on the word "gas" or "oil" was not issued for shale or any other deposits of oil and gas. With the same success we could always call the gas or oil, for example, the American, Russian, Ukrainian - depending on where it is produced. But it is uncomfortably for the marketing. At the same time the definitions "natural gas", "shale gas", "shale oil", "unconventional hydrocarbons" or "coal bed methane" are comfortable for using. But now we know that we are talking about the same mixture of methane, propane, nitrogen, ethane (and other gases, but mainly methane), as well as in other "traditional" cases. I elaborated on this myth, because its "destruction" is necessary for us to disclose the next one:

The Second Myth. The latest methods of unconventional hydrocarbons production. Hydraulic fracturing and horizontal drilling.

Let’s start with horizontal drilling. All drilling process which take place at the sea is a horizontal drilling. It is too expensive to move the platform. I hope, you know that sea drilling has appeared before "shale revolution".

Now let's consider the novelty of hydraulic fracturing and the novelty of oil and gas industry in general. The brothers Nobel became famous not only due to the establishment of the same name prize and invention of the dynamite – they are the Russian industrialists, who constructed an oil pipeline and implemented the methods of transportation and drilling, not new drilling, but mass drilling as such in the process of hydrocarbons production. But were they the first? I address with pleasure to the article in the magazine "Burіnnya" under the authorship of Kurotchin, Danchishak, Mikhalevich, which tells that already in the seventh century AD in Ukraine wells were drilled up to 200 meters depth exclusively for oil production. But only brothers Nobel were able to lay the foundation for the creation of modern oil and gas industry. They launched a full cycle projects - exploration, production, transportation and processing. These projects escalated into the branches of the world economy.

Later, after the first wars the Soviet Union, Canada and the USA established the largest oil and gas scientific centers in Ivano-Frankovsk, Moscow, Edmonton and Houston. May be it is a little strange to you to see in this list Ivano-Frankovsk and Moscow as we used to treat ourselves pejorative, but every fifth engineer on drilling and oil and gas production in the world – is a graduate from Ivano-Frankovsk or Gubkin. Among the Russian-speaking engineers - every second one.

I started this introduction for the myth destruction not to emphasize once again the primacy of Ukraine in all the world's achievements, but to make clear the situation in the modern industry: it's not know-how, but the amount of resources (financial, material, human) that you can bring into the industry. The fact that oil was already produced from the wells thousand years ago has not made Ukraine «oil and gas state» but let’s return to the hydraulic fracturing.

Annually Russia and Belarus produces more than two thousand of hydraulic fractures. At the same time, as you can guess, we are not talking about "shale gas and other unconventional hydrocarbons" production. Belorusneft has established a unit that has already produced more than two hundred of hydraulic fractures. There is an American plant on production of equipment for hydraulic fracturing on the territory of Belarus. Belarus produce hundreds of hydraulic fractures, and Ukraine - just few units per year.

 And now let's compare that to North America - Canada and the USA. CalFrac, Trikan, which are the largest Canadian companies competing on hydraulic fracturing market, produce several dozen a day! It’s more than seven thousand a year! And these are just two companies. Honestly, each of them is worth several billion dollars. So what are the latest technologies of unconventional hydrocarbons production? This is technology of attracting marketing instruments, exchanges, private investors, equipment modernization, which are exactly those technologies that do not work here, and we do not have the experience of using them.

Regarding the technical innovations, I repeat once again that currently Russia and Belarus produce more than two thousand hydraulic fractures annually. In conclusion, I would like to present two quotes from the last magazine of the Ukrainian Union of Drillers, these are excerpts from an excellent article by Nikolai Filimonenko:

«In 1976, after graduating from Donetsk Polytechnic Institute on a speciality "The technology and engineering of mineral exploration", I was sent to Makeevka exploration expedition of the Production Association Ukruglegeologiya. At that time in Donbass extensive works were carried out on the exploration and revaluation of coal deposits reserves. Since then the country focused on its own energy resources, which should have provided the ever-increasing needs of energy-intensive basic industries, the energy shortage could not be allowed.

In Donbass started the industrial tests of the method aimed on hydraulic dismemberment of coal seams in order to hold its preliminary degassing for reduction the probability of sudden emissions of coal and gas on the development of coal seams. The idea belonged to the doctor of technical sciences, the Professor of Moscow State Mining University N.V.Nozhkin. It meant the pumping through a well in the previously uncovered outburst coal seam a large quantity of liquid, containing a filler (e.g. sawdust), with its subsequent removal from the seam. For the first - due to the rock pressure, and then – due to the pumping with using the submersible pumps. Thus, the seam should be deformed under the action of the incompressible liquid. Old cracks should have developed and new ones should have formed in it that would has lead to the stresses in the seam, which, according to scientists, were one of the probable causes of sudden emissions of coal and gas [1, 2, 3]. Herewith, the filler that prevents their complete closure after pumping of liquid, remained in the cracks. This should has increased the permeability of formed porous and fractured reservoir and to promote a better gas output...»

«Soon the first positive results of our work appeared, which confirm the prospects of hydraulic fracturing of coal seams. In 1979 lava came to the pre-torn outburst seam at the mine named after AA Skochinskiy. The area which was the subject of hydraulic fracturing was successfully tested. Of course, the hydraulic fracturing could not influence the state of the coal seam. This created serious problems to the miners during the testing of fracturing influence zone. But as a result this is the coal but not the dead bodies that was issued due to the sudden ejection of miners.

By this time the large volumes of work could be held at the plot. While earlier Makeevskaya GRE rented pumping and sand blender rigs from Poltava  plugging office, four new pump rigs 4aH-700, sand blender rig and many other equipment were bought now. On the basis of Poltava plugging office its own drivers of pump rigs were prepared. The stagnation, which we found out later, was not felt somehow. Honestly, we had no time at all.

 

At that period the gentle outburst coal seams at the fields of mines named after MI Kalinin and AA Skochinskiy (Donetsk), mine №21-bis (Makeevka), mine named after the 18th Congress of the Communist party (Shakhtyorsk), steeply inclined seams of the field of Rumyantsev’s mine (Gorlovka) were exposed to hydraulic fracturing”.

The third myth. An ecological disaster, earthquake and poisoned water. A lot of poisoned water!

I'll start with "a huge amount of water" which is necessary for drilling of well and hydraulic fracturing. The well represents an excavation, the diameter of which is much less than its length. That is a hole of a round cross-cut, where the pipes are inserted in. While drilling, they take the rock-destruction tool and drill bit, attach them to the end of drill pipe and transmit the rotation to the drill bit which "drills" the rock by means of various types of rotary mechanisms (the motors above and below, the special turbines). The bit heats and it should be refreshed. Besides, it is necessary somehow to take out on the surface the drilled rock. In addition, the walls of well fall down, and they need to be strengthened. For this purpose the drilling mud is used,  the basis of which is water.

How much water is it need?

In order to begin deep drilling, for the first it is necessary to put the first pipe column, which serves not to wash the wellhead and not to pollute the upper, aquifer. The depth of installation of such pipe column in average is 300 m, and the hole diameter is 700 mm. The drilling mud is a simple water, in which sometimes clay is added. Thus, according to the formula "the area of a circle which is multiplied by the height" we find the volume of water (PI), multiply by the square of the radius, 0.35 m, and multiply by 300 meters. The results is 115 cubic meters of water. Let’s remember this figure. Actually a slightly different formula based on the gradual consumption are used, but it is clear that the total volume of solution in the well is not more than its size. You probably noticed that the higher the aquarium - its walls are thicker, in such way while drilling the liquid column presses on the walls of the well. What does happen to the aquarium if its walls are not strong enough for the column of pressing water? Right! Glass breaks! That is, is the fracturing of the aquarium.

While drilling of wells there are many areas in which such hydraulic fracturing can occur, that’s why the walls are strengthened by the pipes, and the pipes are cemented from the lower end up to the very top.

This means that our 115 cubic meters of water carried up 115 cubic meters of soil in special pools - settlers. The rock settled, and water with clay began to drill the plot under the next column, which is usually of about 1000 meters long. Thus, the solution is the same – the water and clay. But as the internal diameter of the pipe is less than the outer, so the  water consumption is also less. Let’s leave a couple of inches to the cavity, and we already see a cylinder of radius 0.2 meters and a height of kilometer, thus, we obtain 163 cubic meters of water. But wait, our 115 cubic meters have not gone! Thus, there are 50-60 of additional cubic meters totally.

The column of pipes is inserted and cemented from top to bottom again. Attention! According to the requirements of building regulations, this column should be tested for leaks and excessive pressure. This rule exists for already dozens of years. If the column and annulus of first two pipes are not sealed, the further drilling is not performed. The pipes are pressurized beginning from five megapascals and higher. In any case, this pressure is 10% higher than can be under any operating conditions.

I hope it was interesting for you to know the way in which well is drilled, because if you understood what I wrote, now you can be sure that no oil or gas well is drilled in such way that something flows into or out it. These flows lead to the fact that it is possible neither drill, no produce from the well. If this happens, the millions of dollars are simply poured with cement, that’s all!

Let's recap: we drilled to a depth of 1300 meters, have two (sometimes three) pipes, which are inserted one in another and are cemented from top to bottom, and we used, but not spent, 165 tons of water. Because it has not gone anywhere, but still is in the barns-settlers. The diameter of pipes which are used for the construction of the well with depth of four kilometers, rarely exceeds nine inches, it means that volume of water for drilling does not exceed 250 cubic meters.

If you come to the well, you'll see these barns-settlers, which accumulate the cuttings. In some cases, the non-barn method of drilling is used, then all refining and recycling take place in closed containers.

Now let’s turn to the hydraulic fracturing. The global trend of its application is that now it is much more productive to make several small-fracturing along the horizontal part of the well. The volume of these injections is from 3 to 20 tons.

There is also large-volume hydraulic fracturing. For example, Poltava Oil and Gas Company, POGC, held the fracturing with volume of 1200 tons. Earlier, I participated in it, the largest was the fracturing in amount of 600 tons of acid gel.

What is a gel, and how dangerous is it for the environment and for you personally?

 

Chemical substance	Destination	The Typical applications
Аcids	Promotes the dissolution of minerals and causes fracture in the rock (the preliminary fracturing)	The Cleaner for the pools
Glutaraldehyde	Destroys bacteria in the water	The Disinfectant substance: the antiseptic substance which is used for the medical and dental equipment
Sodium chloride	Сauses the slow decomposition of the polymer gel purposes	The Table salt
N,N-dimethylformamide	Prevents the corrosion of pipes	Is used for pharmaceutical products, acrylic fibers and plastics
Borate salts	Supports the viscosity of a liquid at a certain level while the temperature  increases	Is used for washing detergents, hand soap and cosmetic products
Polyacrylamide	Reduces the friction between the liquid flow and pipe walls	The Water purification, soil conditioner

 

For the first, as we have already found, the columns of pipes which form the well are sealed. Moreover, if they were not be such, the well could not have been drilled. It is checked before making the fracturing. By water. Then, it is checked whether the layer can break, in order to do this they hold the minimal fracturing, then specify what crack will happen and if it is possible to pump the required volume.

One of the "horror stories" is that "we do not know what it is pumped for us" - we know due to the fact that often the customer buys chemicals by himself. For example, the advanced companies hide "the secret recipes under their own brand". Belarusians, for example, do not hide - now the special KDOFs were received – the maps of dangerous factors on receipts of Service Oil - they are available to the Commission, and just are given with other permissive documentation. Reagents are purchased not on the "black market of biological weapon", but from the ordinary suppliers of chemicals and they, almost all of them, are not very different from the composition of shampoos and the liquid soap. Of course, I would not drink them but also would not faint. Just I would wash it with water after contact with skin and that’s all.

Let's come back to 1200 tons of acid gel, which we pumped at the depth of four kilometers. Can it get to our garden or in the river? The most "high" crack, which was obtained during hydraulic fracturing, was received from the field Barnett - its "height" made up 600 meters. Thus, the residents of Poltava and Kharkov regions have nothing to fear.

Now, let’s talk about the size of cracks and earthquakes - the problem of hydraulic fracturing is that cracks squeeze, and this means that they need to be fixed somehow. They are fixed by sand with the diameter of about one millimeter. It’s nothing to say compared to mountain mine production, where Donetsk still stands. Or, for example, if we compare the well to the structure which exceeds the well, drilled by Shell, by  size and environmental danger several times. I'm talking about the sewerage of a small village.

We have already said that the well is a pipe with a capacity of 200 tons of liquid, that the largest hydraulic fracturing in Ukraine amounted to 1200 tons, and now let's look at the district center after May rain:

• The sewerage with a diameter of 500 mm and 200 meters long around the central square is full. Storm water merge in amount of 4 tons per minute in gully that formed, in a small ravine. This water is a solution of salts and oils, exhaust, which were accumulated over the winter in the dust and dirt on the surface of asphalt
• Down the street, after a rain, four house owners wash their cars
• At the end of the street, at a private car wash, there is a turn of some cars, including the car of car wash owner – the Head of the village
• According to the meteorological service, we have learned that 20 mm of precipitation fell over the last 24 hours what is a third of a monthly norm.
• But at the market, from a large heap of garbage, which is always formed after the "market day", the brooks of rain water run cheerfully and get to the same sewerage, which bears its water to the next ravine.

Wait, if the length of roads in the district center is 10 kilometers, and the central area is 100 by 100 meters, so, it is only the rain that three times a month makes fracturing! And what about the drain holes and fertilizers, which are not always, but often applied on the fields and gardens? And it happens not at the depth of four thousand meters.

About the earthquakes. In a common sense, everything is very sad here. The rule of energy keeping states that energy does not born from anywhere, and does not disappear to anywhere. It means that earthquake due to the hydraulic fracturing takes exactly the same amount of energy that the pump rig produces above, on the earth. It is very powerful but is not able to turn the earth. Seismic waves due to the fracturing are detected only by special sensors, and the very moment of fracturing is visible only due to the work of devices.

Many people think that the earthquake could be caused by the subsidence of the rock. It happened, but, unfortunately, it is possible only in the layers of a very large capacity and not in our country. The maximum amplitude of the quake was three balls, it seems to happen in the area of ​​coal mines in the UK.

 

In conclusion, I would like to say that everything should be provided by experts, even antishale PR companies, and we should use common sense and calculator more often!