Saltwater-based fracturing fluid

a technology of saltwater and fracturing fluid, applied in fluid removal, chemistry apparatus and processes, borehole/well accessories, etc., can solve the problems of less efficient removal, poor circulation, and increased rig time cos

Inactive Publication Date: 2018-11-08
KING FAHD UNIVERSITY OF PETROLEUM AND MINERALS
View PDF0 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Benefits of technology

The composition significantly reduces fluid loss during fracturing, maintains permeability, and allows for efficient fracturing operations with minimal fluid volume loss, ensuring effective well performance and enhanced hydrocarbon recovery without the need for additional additives.

Problems solved by technology

Water Blockage or Aqueous Phase Trapping (APT) are among the most important issues that occur in tight formations and fluid loss is a common occurrence in fracturing operations.
Loss of fracturing fluid is an extremely undesirable phenomenon as it (1) leads to poor circulation and therefore less efficient removal of cuttings, (2) requires additional cost in rig time, manpower and material to replenish the lost fluid and restore circulation and in extreme cases, (3) leads to insufficient downhole hydrostatic pressure.
Remediating fluid losses effectively and quickly is still a matter of concern for many companies and operators.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Saltwater-based fracturing fluid
  • Saltwater-based fracturing fluid
  • Saltwater-based fracturing fluid

Examples

Experimental program
Comparison scheme
Effect test

example 1

[0086]Both rheology and coreflooding experiments were conducted to evaluate a developed fracturing fluid system. Seawater (Gulf seawater) with a composition as shown in Table 1 was used to prepare the fracturing fluid as a base. GLDA chelating agent with a pH of 12 was used at two different concentrations; 5 wt % for the unconventional reservoir fracturing and 10 wt % for the conventional reservoir fracturing. The polymer concentration in both cases was 0.45 wt %, relative to the total weight of the fluid. HPHT viscometer was used to measure the viscosity and coreflooding was used to assess the effect on permeability and fluid loss. FIG. 1 shows the flooding set-up used to evaluate the developed systems on actual outcrop core samples for unconventional and conventional reservoirs; one with high permeability and the other one with low permeability. Table 2 shows the different polymers tested with the GLDA in this work along with their stable range of temperature. In addition, Table 3...

example 2

[0087]FIG. 2 and FIG. 3 show viscosity measurements of a fracturing fluid composition that includes 10 wt % GLDA and 45 pptg co-polymer diluted in seawater at 300° F. and 300 psi. The viscosity increased to an average value of 350 lb / 100 ft2 and remained stable for more than 4 hours and then declined to 0.5. As a result, this fluid composition can be used for high permeability or conventional reservoirs. The pH of the fluid was about 12.

[0088]FIG. 4 and FIG. 5 show viscosity measurements of a second fracturing fluid composition that includes 5 wt % GLDA and 45 pptg co-polymer diluted in seawater at 300° F. and 300 psi. The viscosity increased to an average value of 135 lb / 100 ft2 and remained stable for more than 6 hours and then declined to 0.5. As a result, this fluid composition can be used for low permeability or unconventional reservoirs. The pH of the fluid was around 12.

[0089]FIG. 6 shows the two coreflooding samples (Berea and Scioto sandstone cores) used in this study and t...

example 3

[0090]FIG. 7 and FIG. 8 show the coreflooding behavior of the two experiments for the conventional and the unconventional coreflooding samples. FIG. 7 shows that the pressure elevated soon after GLDA / polymer solution was injected, and the outlet flow rate remained zero for more than two hours. After reaching a peak value, the pressure went down due to a breakage of the solution. The core permeability was observed to be 150 md before and after the experiment. As a result, the coreflooding did not damage to the formation, due to a zero fluid loss behavior of the treating fluid.

[0091]Similarly, FIG. 8 shows that the pressure went up after GLDA / polymer solution was injected, and the outlet flow rate remained zero for more than four hours. After reaching a peak value, the pressure went down due to a breakage of the solution. The core permeability was observed to be 3.2 md before and after the experiment, which implies no damage to the formation, due to a zero fluid loss behavior of the t...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

PropertyMeasurementUnit
impuritiesaaaaaaaaaa
temperatureaaaaaaaaaa
temperatureaaaaaaaaaa
Login to View More

Abstract

A fracturing fluid composition that includes a chelating agent, e.g. GLDA, and a polymeric additive comprising a copolymer of acrylamido-tert-butyl sulfonate and hydrolyzed polyacrylamide diluted in an aqueous base fluid, e.g. seawater, and a method of fracking a geological formation using the fracturing fluid composition. Various embodiments of the fracturing fluid composition and the method of fracking are also provided.

Description

BACKGROUND OF THE INVENTIONTechnical Field[0001]The present invention relates to a fracturing fluid composition that includes a chelating agent and a polymeric additive diluted in an aqueous base fluid. The present invention further relates to a method of fracking a geological formation using the fracturing fluid composition.Description of the Related Art[0002]The “background” description provided herein is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent it is described in this background section, as well as aspects of the description which may not otherwise qualify as prior art at the time of filing, are neither expressly or impliedly admitted as prior art against the present invention.[0003]Hydraulic fracturing is a prominent fracturing method amongst permeability-impaired formations (i.e. low permeable reservoirs, e.g., shale-gas and tight-gas with a permeability of no more than 0.5 md (milli-darcy) for o...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & AuthorityApplications(United States)
IPC IPC(8): C09K8/68E21B43/267C09K8/52C09K8/80
CPCC09K2208/12E21B43/267C09K8/68C09K8/52C09K8/80C09K8/882C09K8/88C09K8/685C09K8/887C09K2208/28C09K8/725C09K8/74
InventorMAHMOUD, MOHAMED AHMED NASR EL-DINELKATATNY, SALAH EL-DINMOHAMMAD, MARWAN NAGM ELDEEN
OwnerKING FAHD UNIVERSITY OF PETROLEUM AND MINERALS