Coiled-Tubing Reverse Circulation - An Efficient Method of Cleaning Horizontal Wells in a Mature, Pressure-Depleted Field

Kumar, Parveen; Amri, Badr Ali; Kouli, Pawan; Gisbergen, Stan Van; Ferdiansyah, Erik; Mowat, Paul Murray

doi:10.2118/92804-ms

Cited by 5 publications

(5 citation statements)

References 6 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Several cleanout techniques have been developed over the years, these include stationary circulation, wiper tripping (1,2,(4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18) , reverse circulation (19)(20)(21)(22) , sand vacuuming technology (23)(24)(25)(26)(27)(28)(29)(30)(31)(32)(33)(34)(35)36,37) , and venturi sand/junk bailers (4,22,(38)(39)(40) .…”

Section: Sand Cleanout Methodsmentioning

confidence: 99%

“…Reverse Circulation Cleaning (5,(19)(20)(21)(22) In some cases the forward circulation mode cannot effectively clean the fill out of the wellbore because the size of CT limits the achievable circulation rate required for circulation/wiper trip methods. Because of the smaller internal flow area of CT, it is often possible to achieve higher circulation velocities inside the CT and, where appropriate, fill can be effectively transported by reverse circulating up the CT.…”

Section: Conventional Hole Cleaning Methodsmentioning

confidence: 99%

“…96 119 124 125 142 157 161 161 176 195 199 200 212 242 252 254 254 254 273 289 292 293 293 292 283 269 254 240 225 211 198 185 172 161 149 137 127 Temperature, ˚F Viscosity @ 100 sec-1, cP Sand/Junk Bailers (3,21,(38)(39)(40) Over the years different types of sand bailers have been developed for use with jointed pipe, wireline and CT for the removal of large and/or heavy particles and debris. By far the commonest type of bailer used for coiled tubing is the venturi junk basket (4,22,38) . This tool is not dependent on hole size to work, so, for example, a 2 1 / 8 -in.…”

Section: Conventional Hole Cleaning Methodsmentioning

confidence: 99%

“…Compared with the wells cleaned by the sand vacuuming, the BHP and the ECD in these wells with wiper trip cleanout are relatively high, and the average of BHP is approximately 4,500 psi and the ECD is 1. 22 ECD in the wells with the sand vacuuming are 960 psi and 0.68, respectively. The lowest ECD is 0.09 A typical pump rate for the sand vacuuming operation is between 0.3 bpm to 0.75 bpm ( Figure 9) depending on the size and length of the CCT string.…”

Section: Overview Of Sand Cleanout Operationsmentioning

confidence: 99%

See 3 more Smart Citations

Sand Cleanouts With Coiled Tubing: Choice of Process, Tools and Fluids

Li¹,

Misselbrook²,

Sach³

2010

Journal of Canadian Petroleum Technology

View full text Add to dashboard Cite

Summary Cleaning fill from wellbores is the most common coiled tubing (CT) application. The process is a function of multiple variables including fluid properties, flow velocities, wellbore geometry and deviation, pipe eccentricity, particle properties, fill penetration rate and wiper trip speed. Removing fill from wells with low bottom hole pressures (BHP) can be challenging especially if wells are completed with smaller diameter production tubulars which significantly reduce circulation flow cross-section and choke flow(1). Such challenges are further compounded by high deviation or horizontal well trajectories especially in large diameter wellbores. A variety of cleanout methods have been developed in the past, often incorporating high circulation rates, special fluids, wiper trips, or reverse circulation to remove solids. Many of these conventional sand cleanout methods often apply excess hydrostatic pressure on the formation, resulting in lost circulation in pressure depleted reservoirs. The conventional solution to overcome excess hydrostatic pressure has been to include nitrogen to reduce fluid density and thus lessen the hydrostatic head; however, sand vacuuming technology using a concentric coiled tubing (CCT) with a downhole jet pump is an alternative technique for removing fill without placing a hydrostatic load on the reservoir. This paper reviews the individual sand cleanout systems and discusses the advantages and limitations related to each method. In recent years, cleaning sand using the wiper trip method has become the preferred technique. However, an appropriate pump rate and reservoir pressure are needed to maintain a proper return flow rate to carry the sands to the surface. For pressure-depleted reservoirs completed with horizontal wells, a sand vacuuming system can be used to efficiently remove the debris without circulating nitrogen and without high pump rates. When the fill cannot be removed from large-diameter deviated wellbores using conventional low-cost cleanout fluids, then fluids with high solids suspension capability (under shear conditions) in conjunction with wiper tripping may be an economical option. The main application for the reverse circulation technique is cleaning sand from large diameter wellbores when the necessary pump rates for conventional "forward" circulation are not achievable. A venturi junk bailer is often used to retrieve larger or heavier material which cannot be circulated out by traditional methods. Field cases are provided, demonstrating how to select the proper cleaning method and how to efficiently remove sand from a wellbore based on both operational and logistical conditions.

show abstract

Section: Sand Cleanout Methodsmentioning

confidence: 99%

Section: Conventional Hole Cleaning Methodsmentioning

confidence: 99%

Section: Conventional Hole Cleaning Methodsmentioning

confidence: 99%

Section: Overview Of Sand Cleanout Operationsmentioning

confidence: 99%

See 2 more Smart Citations

Sand Cleanouts With Coiled Tubing: Choice of Process, Tools and Fluids

Li¹,

Misselbrook²,

Sach³

2010

Journal of Canadian Petroleum Technology

View full text Add to dashboard Cite

show abstract

“…Some researchers applied the reverse circulation technology to the wellbore cleaning. Kumar et al 10 attempted to use coiled tubing reverse circulation for cleaning petroleum horizontal wells, and an average increase in 15% in water injection rate was improved. Ozbayoglu et al 11 proposed a layered cuttings transport model for high-angle and horizontal wells and analyzed the effects of major drilling parameters, such as flow rate, fluid density, and gas ratio, on cuttings transport efficiency.…”

Section: Introductionmentioning

confidence: 99%

Pressure drop characteristics of reverse circulation pneumatic cuttings removal during coal seam drilling

Han

Song

2020

Science Progress

View full text Add to dashboard Cite

To solve the problems that the borehole depth is shallow and the drilling efficiency is low during the gas drainage drilling in soft coal seam with current cuttings removal method, a new technology of reverse circulation pneumatic cuttings removal is proposed. The working principle of reverse circulation pneumatic cuttings removal is analyzed, and the kinetic equation of cuttings in the inner hole of the drill pipe is established. Through experiments, the pressure drop in the drill pipe is measured to reveal the effects of air velocity, cuttings mass flow rate, and cuttings particle size on the pressure drop in inner hole of the drill pipe. When the cuttings mass flow rate is constant, the pressure drop increases with the increase in air velocity. When the air velocity is constant, the pressure drop increases with the increase in cuttings mass flow rate. At low air velocity, the pressure drop of cuttings is primary. As the air velocity increases, the pressure drop ratio of cuttings decreases. Under the same conditions, the order of pressure drop with different particle size cuttings is coarse cuttings > medium cuttings > fine cuttings. Empirical equation of pressure drop coefficient of cuttings is established, which is in good agreement with the actual data.

show abstract