Thursday, September 20, 2012

Drilling and Producing Crude Oil and Natural Gas

This article demonstrates how crude oil and natural gas wells are drilled.

One of the main questions is how do we find the traps where these natural resources are found? Years ago it was based on the ancient strategy called "luck". Producers would simply drill one well right at the side of another; there were no scientific methods, just simple guess work. By doing this the landscapes really suffered.

Today the good luck and guess work have been replaced with science and technology, the same technology and principles that are used for drilling in Alaska, Texas, and Oceans and even in the Middle East.

Suppose a geoscientist finds a possible trap, meaning that potentially there is either crude oil or natural gas in that location. This presents us with some common questions.

First, are there giant pools of crude oil and gas under the ground or do we get it from certain rock formations?

Secondly, how do we extract that natural resource from the earth and create energy out of it?

Once the geologist find a trap that could contain crude oil and gas a drilling rig is brought in.

What is a drilling rig and how does it work?

The drilling rig is a piece of equipment that is brought onto the rig for five or six or seven days which drill a hold about the size of a football and is capable of drilling down several thousand feet down into the earth's surface. Once the hole is drilled a variety of sensitive instruments called logging tools send electronic messages that provide a detailed record of the rock and fluid properties of the geologic formations.

A typical rotary drill rig goes about 5,000 feet down. Imagine taking 16 football fields and placing them end to end and turning them upright, that's about 5,000 feet.
The rigs process is very similar to drilling through a piece of wood, only the drill bit is about the size of the football we mentioned earlier. The drilling is performed by highly trained members of a drilling crew.

Once the rig has drilled through various rock formations, steel piping is placed in the ground, then a cement shield is placed around the pipe to protect any water table or aqua furs, the piper is then perforated a and fractured only at the crude oil and natural gas rock formation to allow the flow of these vapours and liquids to move up the well to the surface. If the rock formation contains enough crude oil and or natural gas the rotary drill rig will be replaced with a pumping unit. Now the purpose of this is to keep the crude oil and natural gas flowing. Crude oil is sent into storage tanks and natural vapours are sent into vapour pipelines.

Often times today we need a drill in areas that won't allow us to drill down straight vertically, but with some of the latest technologies we are now able to drill directionally, this is an excellent way, for example to drill under a park or a school's property, many pre-developed areas tend to be a great place for crude oils r natural gas so the directional drilling technology is a great way to retrieve the source.

So what is the cost?

The costs usually ranges from 350,000.00 to 1, 000, 00.00 and an offshore well can cost up to a billion dollars per well and there's still no guarantee it will even produce.

I'll now use Ohio, USA as a case study

In Ohio there is over 64, 00 crude oil and gas wells producing in 49 of Ohio's 88 counties, with more than 273, 00 well drilled.

Do all Ohio counties produce crude oil and natural vapours?

The answer is no! The potential geological formations that contain crude oil and gas simply do not exist throughout the state which is why technology plays such a key role in retrieving this vluable rescource.

Now back to a question asked at the beginning of this article -

Once we have drilled to our targeted rock formations, how do we get the crude oil and natural gas out?

Utilising scientific principles of movement the fluids, crude oil and vapours are lifted out of the ground to the surface using a variety of different pumping units. How do these units work? Well first of all kepp in midn that if a pump jack is not moving then it doesn't mean that a well is not producing. The pump is just turned on long enough to create a syphoning effect. Petroleum engineers, production supervisors or well tenders will typically determine how long each individual well should be turned off and on. Also, keep in mind that the motor on this pumping unit also need energy to work. This energy is either the well's own gas source or electricity or solar panels. If electric is used the pumping units may be switched on overnight during off-peak electric times.

Where does it go when it's out of the ground? The first place it will go into will be a separator, the separator separate the crude oil liquids from the gas vapours. the crude oil when then move onto a storage unit called a Tank Battery and the vapours will be transported through a number of Natural Gas Pipelines for distributions.

Why can't you always see these crude oil and gas wells? New technology allows us to have a very small environmental footprint. These wells are hidden by plants and other landscaping like and can be found in car parks or in back yards if schools, churches, cemeteries, parks, cornfields or even your own back yards and these wells can produce energy for decades.

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