Plugs for hydraulic fracturing generally are pumped into horizontal wellbores. Initially, the goal was to get the plugs to depth without careful consideration of the amount of water used in the pumping. As the industry has grown, a better understanding of pump-down methods and techniques has resulted in a realization that these pumping inefficiencies should be improved.
When completing a horizontal well using the plug-and-perf technique, water is required to push the bottom hole assembly (BHA), containing a frac plug, to the target depth. With over one million frac plugs having been pumped in North America, large data sets are available to quantify the pump-down efficiency of these operations. This past information, along with a working model of how pump down works, can be used to promote improvements in pump-down efficiency, reducing water usage and rig time.
The efficiency of the pump-down operation can be calculated based on pump time, displacement volume, and the actual volume of fluid pumped. This type of information can be recorded during operations. The pump-down efficiencies can be calculated as a percentage of actual versus calculated volumes pumped and is often expressed as a relational number, such as how much fluid is needed per 100 feet of casing. These numbers can be used as a metric for the amount of water and time required to move the plug to its desired location.
Over 10,000 frac plug pump downs from diverse North American regions were analyzed to attain a baseline for efficiency during frac plug pump down operations. The force, pressure, and fluid velocity effects acting on the BHA during pump down were analyzed to understand how to better quantify methods and designs that increase or decrease efficiency. Finally, procedures were mapped out on the operational units used in pump down to understand the potential impacts on efficiency.
The result is a guide on gauging pump-down efficiency of past operations while understanding methods to increase these efficiencies in the future. This framework can be used to view how a frac plug is pumped downhole while understanding the relationships that control its efficiency. This model can be used to evaluate past operations as well as design for future operations to increase overall efficiencies and decrease water usage and time on location.
For the second YEPP event in 2005, Wim Turkenburg, Professor at the Copernicus Inst. of Sustainable Development and Innovation Science, Technology, and Society Div. of Utrecht U., gave a comprehensive lecture on CO2 emission reduction. Thirty-six young (and some more experienced) professionals of the E&P industry in The Hague and surrounding area attended. In 2001, fossil fuels made up almost 80% of our world's energy consumption, and CO2 emissions are related mainly to the consumption of fossil fuels. Because western countries cause 58.6% of global CO2 emissions and the emerging regions in Asia Pacific are rapidly gaining ground, those consumers should take the lead in reducing emissions and their adverse effect on global climate change, he said. Energy conservation and the use of renewables would lead to the largest drop in emissions, but CO2 recovery and storage remains a good number three on the list of methods that should be tried, he said.
The major challenge facing society in the 21st century is to improve the quality of life for all citizens in an egalitarian way, by providing sufficient food, shelter, energy and other resources for a healthy meaningful life, whilst at the same time decarbonizing anthropogenic activity to provide a safe global climate. This means limiting the temperature rise to below 2 C. Currently, spreading wealth and health across the globe is dependent on growing the GDP of all countries. This is driven by the use of energy, which until recently has mostly derived from fossil fuel, though a number of countries have shown a decoupling of GDP growth and greenhouse gas emissions from the energy sector through rapid increases in low carbon energy generation. Nevertheless, as low carbon energy technologies are implemented over the coming decades, fossil fuels will continue to have a vital role in providing energy to drive the global economy. Considering the current level of energy consumption and projected implementation rates of low carbon energy production, a considerable quantity of fossil fuels will still be used, and to avoid emissions of GHG, carbon capture and storage (CCS) on an industrial scale will be required. In addition, the IPCC estimate that large scale GHG removal from the atmosphere is required using technologies such as Bioenergy CCS to achieve climate safety. In this paper we estimate the amount of carbon dioxide that will have to be captured and stored, the storage volume and infrastructure required if we are to achieve both the energy consumption and GHG emission goals. By reference to the UK we conclude that the oil and gas production industry alone has the geological and engineering expertise and global reach to find the geological storage structures and build the facilities, pipelines and wells required. Here we consider why and how oil and gas companies will need to morph into hydrocarbon production and carbon dioxide storage enterprises, and thus be economically sustainable businesses in the long term, by diversifying in and developing this new industry.
Natural gas is a vital part of the energy supply system in the Middle East. However, despite the fact that large resources of natural gas are present, several countries have to rely on imports for the domestic gas consumption. These countries have recently put forward ambitions to change this and become self-sufficient or even larger exporters of (Liquefied) Natural Gas. Regional countries have articulated to become self-sufficient in the future. This can be realised by at first lowering growth of domestic natural gas consumption by replacing electricity production by renewable and nuclear power.
However, despite the fact that large resources of natural gas are present, several countries have to rely on imports for the domestic gas consumption. These countries have recently put forward ambitions to change this and become self-sufficient or even larger exporters of (Liquefied) Natural Gas. Regional countries have articulated to become self-sufficient in the future. This can be realised by at first lowering growth of domestic natural gas consumption by replacing electricity production by renewable and nuclear power. Other means to free up gas for consumption are increased energy efficiency (typically 2 to 5% of production) and finding alternatives for natural gas Injection for pressure maintenance (up to 30% of production).
Liquified natural gas (LNG) is the liquid form of natural gas at cryogenic temperature of 265 F ( 160 C). When natural gas is turned into LNG, its volume shrinks by a factor of approximately 600. This reduction in volume enables the gas to be transported economically over long distances. Over the past 30 years, a considerable world trade in LNG has developed. Today, LNG represents a significant component of the energy consumption of many countries and has been profitable to both the exporting host countries and their energy company partners.
Natural gas is a key source of fertilizers in the form of ammonia and urea. Ammonia is the second largest chemical product produced in the world, behind sulfuric acid. The demand for ammonia is driven by the demand for fertilizers. Of the world's nitrogen demand, 85% is for fertilizer primarily derived from ammonia in the form of: Other uses of ammonia include fibers, resins, refrigeration, and pulp and paper industries. Ammonia can be produced from different hydrocarbon feedstocks such as natural gas, coal, and oil.
This page explores the fundamental relationships underlying gas reservoir performance and presents some simple techniques for forecasting production rate vs. time. One way to envision the different factors affecting the performance of a gas reservoir is to define the production "system" with three components: Rate vs. time behavior is governed by the combined effect of these three parts, which in turn have performance characteristics that vary with pressure and production rate. If these relationships are plotted on the same presentation, the resulting graph will look like Figure 1. At low flow rates, the equipment-performance curve is nearly horizontal, reflecting the small flowing frictional pressure drops in the system. If there is liquid holdup in the production tubing, multiphase-flow calculations can show the curve bending upward at low production rates.
Compressed natural gas (CNG) transportation is used in very small systems in environmentally sensitive areas. Sometimes the gas is transported to remote filling stations for CNG-fueled vehicles. Large-scale transportation of CNG is not yet commercialized but is considered economically feasible and is being pursued actively by several companies. In the 1960s, Columbia Natural Gas of Ohio tested a CNG carrier. The ship was to carry compressed natural gas in vertical pressure bottles; however, this design failed because of the high cost of the pressure vessels.
The objective of the paper is determining the effects of reducing the sulfur content in diesel on its properties, specifically lubricity and electrical conductivity, and the optimal injection rates of lubricity and anti-static chemicals when producing maximum 10 ppm sulfur diesel product from 50/50 Arab Light and Khurais Crude Feed. The optimal injection rates should ensure that the 10 ppm sulfur diesel product will achieve the required product specifications in terms of lubricity and electrical conductivity while maintaining an economically sustainable consumption of the injected chemicals. The test run commenced with collecting a 10 ppm diesel reference sample from the refinery diesel rundown before injecting the chemicals. Then, the chemical injection of both lubricity and antistatic improvers was commenced. The injection rates of the lubricity and antistatic improvers were adjusted via the pump stroke once per day. After that, two samples of the diesel product rundown stream had been collected. The daily samples were analyzed for their lubricity and electrical conductivity by performing the test procedures ASTM-6079 and ASTM D-2624 respectively. the test results for the lubricity test run indicates that the ideal injection rate for the lubricity improver chemical is at 70.0 ppm where the lubricity specification of Max. 460 μm is met with optimal consumption of the chemical. On the other hand, electrical conductivity results were always significantly above the 10 ppm sulfur diesel product minimum specification of 50 μS/m regardless of the conductivity improver chemical injection rate. At the lowest turndown of the pump of 0.49 ppm injection rate, the lab results fluctuated between 280 μS/m and 780 μS/m. Although the product conductivity specification had been met in the test trial, the conductivity improver chemical was stronger than required. Therefore, another alternative chemical that is compatible with the equipment of the injection system may be considered.