Sure Energy

The research being applied to sources of clean energy seem to be increasing throughout the years.  As observed with the disaster in Japan, each energy source has some flaws to it.  Nuclear reactors produce fear in the public just as the instance in Fukushima.  Radioactive elements released into the atmosphere is a big issue and despite the fact that statements have been made that there are minimal amounts present which are not "likely" to increase health problems, there IS still that possibility that radiation may raise chances of health problems to those individuals exposed.  The oil spill was certainly a disaster and set many businesses back for a period of time.  Oil exposed to the atmosphere however, has less (basically zero) human health impacts.  In the case of wind farms and solar power, large amounts of turbines as well as panels are required to produce incremental amounts of energy that oil and natural gas are capable of generating.  Technology in drilling seems to strike significant findings in the aspect of ways to improve economic operations in the extraction of hydrocarbons in spontaneous instances.  These advancements change the whole perspective of fossil fuels, like shale and tight gas sands have done so recently.  The minds of engineers and R&D staff in the oil and gas industry are always turning, and there are multiple methods to improve economic recovery out there that are waiting for that one spark to begin applying practices in industry.  The spark may come tomorrow, next month, or a year from now.  Natural gas is said to be cleaner burning fuel than oil, but a refining technique may arise an option to generate cleaner fuel in the future with the quick changes that the ever expanding oil industry experiences.  The public seems to want to through out drilling for hydrocarbons much more easily than other sources of energy which can result in a disaster such as a nuclear one for example.  Cleaner energy is more beneficial to the environment, but the fact is that the U.S. is starving for energy, and the one sure source which has been around for many years is oil.

Stimulation Video

As an extension to my last post, here is a video that shows the basics of the hydraulic stimulation of a well.  The video also shows the basics steps to followed to drill a horizontal well which is the majority of the type of wells being drilled today.

What is a Frac Job?

I've had several posts on frac jobs of oil and gas wells.  It is actually a complex process and there is a lot of chemistry that goes into the design of a frac.  Each frac is specific to the well and its properties such as pressure, temperature, pH level, lithology, and others.  Thousands of gallons of water are used for frac jobs and very miniscule amounts of chemicals (.004% per thousand gallons of water) can completely alter the properties of the fluid .  The idea of a fracture job is to create a super highway for hydrocarbons to travel into the producing wellbore.  The shape charge perforations which I explained in earlier posts are the first step to the job.  The frac fluid is pumped into the wellbore and uses a crosslinker to suspend sand proppant and carry it into the perforation.  The crosslinker can vary from fluid to a solid composition such as one that Schlumberger uses.  The crosslinker can be modified to delay the conversion of the fluid into gel so optimization of sand suspension and placement can be achieved.  The type of sand used depends on the pressure encountered at the fracture.  Some sand can be crushed if the pressure is too great and man made ceramics can be used in these cases.  Once the gel has carried the sand into the fractures to create a super hydrocarbon highway, a breaker is added to return the fluid system to a less viscous state.  The fluid is pumped back to surface returning the majority of chemicals and additives in the fluid system to tanks on surface while leaving the proppant to maintain the fracture open.  This method of stimulating a well has become routine for nearly every well drilled in order to enhance production.  This method is the technology driving these tight gas sands and shale research for economic production of new reservoirs being discovered today.  Multiple zone fractures are highly common and a 3D image is seen below to monitor the effectiveness of a hydraulic fracture stimulation job.  Each color represents a different zone.

A frac job also requires a lot of hydraulic horsepower.  This is achieved by connecting several pump trucks ranging from 1000 hp to 3000 hp each to a unit called missel located in between the group of all the trucks.  

Video Blog

Here is my very FIRST video blog post ever.  It's a little hairy, didn't really know what I was doing or what I wanted to talk about exactly, but there's some good background info about the drilling industry.  Enjoy!

Blog Evaluation #2

Frac for more oil.

This post is to add a little more on the last post as well as to give you a good laugh.  Fracturing and stimulating wells, to increase hydrocarbon production, has angered many people in terms of ground water contamination.  Groundwater contamination can be due to many other things rather than just drilling and stimulation, such as land fill waste, factory or plant waste disposal and other things.  The blame seems to be entirely aimed at drilling activity however.  Fracturing occurs in zones which contain hydrocarbons.  These reservoir zones are typically 8,000 feet deep or can be up to 12,000 feet in deeper wells.  This is the depth at which hydraulic fracturing and acidizing takes place.  The groundwater aquifer is near 100 feet deep and not remotely close to the fracturing chemicals being used to stimulate reservoirs.  The chances of these chemicals traveling through several alternating impermeable layers of rock to the groundwater source is very very unlikely.  Just another example of blame being fired at oil companies when other sources of contamination are igonred during the first steps of pointing fingers.  Below is a hilarious video (possibly slightly improper) in my opinion that doesn't have much to do about actual fracturing of wells but none the less will provide a good laugh.  Enjoy!



Drilling.....Safer than walkin' across the street blindfolder.

My last couple of posts have been about drilling's interaction with the environment and regulations which are strictly enforced to protect it.  I will continue with that subject in this post and talk a little more about regulations.  There are basic steel pipes which are called casing and are set in the wellbore in order to provide zonal isolation as well as wellbore stability.  Surface casing is VERY important in order to isolate groundwater (drinking water) from drilling fluids and chemicals used to acid fracture or stimulate reservoirs.  Groundwater is typically around 100' deep and is often isolate by conductor casing which is the very first section of casing set when drilling.  State regulations vary, but a relatively standard regulation is that surface casing must be set minimum of 300' below the bottom of the ground water zone and cemented properly.  Cement bond logs, which are legally required, test the integrity of the cement and make sure complete zonal isolation is achieved.

Many people have accused drilling companies to have contaminated ground water, but the fact is that strict regulations and monitoring of drilling through permits has been in the industry for many years and continue to become more strict as the years progress in order to mitigate these problems.  Members of the Oil and Gas Conservation Commission presented in one of my classes this week and confirmed the increase in regulations of drilling are unavoidable.  These regulations include well spacing also, where wells being drilled have to go through a specific permit in order to ensure adequate acreage spacing between other wells.  They discussed a situation where a farmer's groundwater was suspected to have been contaminated with methane gas from a nearby well.  Immediate action was taken by conducting CBL's as well as sampling gas from the well and the farmer's water.  It was determined that a bad cement job of the casing had allowed gas to travel in between the intermediate and production casing and enter the water zone.  Cement squeeze jobs can be conducted in order to fix cement job problems such as this one, but the OGCC realized the matter was of huge concern and violation of regulations.  The operator of the well was required to plug and abandon the well and lose money from shutting down of production from the well as well as abandoning material costs.  Plugging and abandoning a well also has strict and strongly enforced regulations by states.  As Capt. Carbon Sequester mentioned on my last post, other industries have had failures as well such as the Minneapolis bridge collapsing.  Sure the bridges were subject to more strict inspections, but the civil and mechanical engineering industry did not take such huge hits as big oil companies, or small companies, have taken over many smaller incidents over the years.  Individuals need to become more informed about the regulations drilling operations are required to follow and possibly see the side that extreme caution is being take when trying to suffice the U.S.'s hunger for more oil by drilling oil and gas wells.  What do you think about that?