[Mettezz]

A friend of mine told me that only 33% of oil gets pumped out of an oil field.
He also said that if you increase that by 1% we wil get more oil for 5 more years.
He didn't show me any evidence of this assumption. so it's probably bullshit.

But that makes me wonder how oilfields work and how much oil they can't pump up from one oilfield.

i know that they put water inside oilfields to keep the pressure up and eventually they will only pump up water.

But how much % can they pump out of one oilfield is it really only 33%?

Or give me links where i can find some information about it please

[KillTheHumans]

$this->bbcode_second_pass_quote('Mettezz', 'A') friend of mine told me that only 33% of oil gets pumped out of an oil field.

[MonteQuest]

ASPO states that the average global recovery factor is about 30-35%. This is based on data from the IHS Energy database on 9,000 fields worldwide containing 1,400 Gb reserves.

Since this is an average, obviously some fields have higher recovery rates. Rates of 50% and even 55% have been achieved in the North Sea.

Economics and EROEI limit oil recovery to this small percentage.

[Mettezz]

Thx KillTheHumans, and montequest for replying

it's not easy to find information about things like this

[Armageddon]

It's all about the pressure too. Oil is not sucked out of the ground, its pressure forces it out. There are ways to keep this pressure going after the pressure sudsides, but it is only temporary. There comes a point when an oil well takes more energy extracting the oil out than it produces. When this happens, the well is capped. So yes, oil fields do reach a maximum point of extraction, then start to decline. This is happening all over the world, especially to major oil fields. Also, the world has peaked in conventional oil. We are now declining.

[TheDude]

The Wiki page on Oil depletion is a good start, it'll give you the basics.

[basil_hayden]

Do an experiment for yourself.

Fill a common kitchen strainer with soil. Weigh it.

Get some vegetable oil, weigh it.

Pour vegetable oil in it slowly so as to cover all the soil.

After a while, some of the oil will find its way through the strainer.
This is what is referred to as gravity drainage; that oil can be pumped.

Weigh the oil soaked soil in the strainer again.
You'll find that at least 2/3 of the oil is stuck in the soil if you distributed it well.

The oil stuck in the soil can't be pumped.
Tertiary recovery was invented to get that stuff.
Even tertiary recovery has its limits.


How does the experiment differ from reality?
The pore space in soil at the earth's surface is much higher than the pore space of host rock miles below the earth's surface.
Crude oil is much thicker (less viscous) than vegetable oil.

[rockdoc123]

$this->bbcode_second_pass_quote('', 'T')he oil stuck in the soil can't be pumped.
Tertiary recovery was invented to get that stuff.
Even tertiary recovery has its limits.


How does the experiment differ from reality?
The pore space in soil at the earth's surface is much higher than the pore space of host rock miles below the earth's surface.
Crude oil is much thicker (less viscous) than vegetable oil.

[KillTheHumans]

$this->bbcode_second_pass_quote('GASMON', 'N')ow I'm a gas engineer, (gas distribution), though oil (& gas) in the ground is not my department. Very surprising figure re remaining oil (33%)

So, a hell of alot of oil will be left in each field, unrecoverable, or uneconomically unrecoverable.

(Probably daft) Question - Is there possibly a way to get the energy out of this oil, in situ. Pump air into it, aireate it & burn it underground. This happens in some coalmines, spontaneous combustion. Perhaps using heat produced to make steam. then electricity.

[basil_hayden]

I was trying to keep it simple, doc, but thanks for the details, and yes I still always mix the viscosity up - that's why I put what I meant outside parenthesis. Thanks for catching that.

As an environmental geologist, among other things I work on oil spills that reach the subsurface and float on the water table. I once worked on a project that had 12 feet of floating oil on top of the water table; it bubbled to the surface as 18 wheelers drove over it. That's how the problem was discovered.

In a very permeable sandur deposit with 39% porosity and a conductivity on the order of 10E-2 cm/sec (coarse beach sand for the lay folks), the recovery of 20,000 gallons of No. 2 oil from a 60,000 gallon spill was considered a success. In other words, there was no more mobile product after the 20,000 gallons was collected. Bioremediation, surfactants and oxidizers got another estimated 5,000 gallons. The rest was excavated and brought to an asphalt batching plant. Damn big hole, about 2.5 acres 15 feet deep, or 75,000 cubic yards. The bill was even bigger.

What I don't have available that a petroleum geologist does is the drive mechanism - pressure. No confining layers of suitable thickness at the surface. I can pretty much only depend on gravity not density changes, maybe an occasional steam injection project to recover No. 6 oil which is very thick (I give up on viscosity, LOL).

20 years in the business and I'm in the 50,000 gallon club for recovered, free floating product.
Not bad when you consider a teaspoon of oil in a railcar full of water would render that water non potable according to regulatory standards. Much more than that in impacted soils.

Of course, we don't see releases of this volume often anymore. It wasn't environmental awareness that stopped the releases, it was the cost of cleanups, ask any responsible party....the first gallon comes out for 100 bucks, the last gallon comes out for about 100,000 bucks. I'd guess that relationship is inverse for the two industries, attributable to the low-hanging fruit parable.

[TheDude]

$this->bbcode_second_pass_quote('GASMON', '(')Probably daft) Question - Is there possibly a way to get the energy out of this oil, in situ. Pump air into it, aireate it & burn it underground. This happens in some coalmines, spontaneous combustion. Perhaps using heat produced to make steam. then electricity.

Dont bite my head off please !!! - But I remember reading something similar a while ago with coalfields. Probably bugger up the local water supplies, etc so an environmental nightmare.

[basil_hayden]

$this->bbcode_second_pass_quote('TheDude', '
')Cleaning up oil spills sounds maybe akin to Steam assisted gravity drainage. Think your business will be picking up soon, Basil? We have newfangled messes like coal bed methane to clean up. after all.

[MonteQuest]

$this->bbcode_second_pass_quote('GASMON', ' ')If we cant get the oil, can we get its energy ??? Can the EROEI be overcome ?.

[MonteQuest]

$this->bbcode_second_pass_quote('GASMON', ' ')My thread was a technical question to ask if THE ENERGY CONTENT of any remaining oil which cannot be produced, either for technological & / or economic reasons, can be released with a positive EROEI.

Gasmon

[KillTheHumans]

$this->bbcode_second_pass_quote('MonteQuest', '
')
No, the EROEI cannot be overcome. If it takes more energy to get the oil than you get from it, you leave it in place.

[KillTheHumans]

$this->bbcode_second_pass_quote('MonteQuest', '
')
The 35% average figure is from limits due to both economical and EROEI limits.

So, the answer is no. This figure has been the average since the 1960's.

[MonteQuest]

$this->bbcode_second_pass_quote('KillTheHumans', ' ')35% recovery from primary production has nothing to do with EROEI limits, go read what RocDoc said, its more a function of the drive and the geology, including permeability.