GB2506603A

GB2506603A - Drilling fluids comprising ground grape seeds

Info

Publication number: GB2506603A
Application number: GB201217607A
Authority: GB
Inventors: Brendon Steven O'toole; Brendon O'toole; James Victor Jones
Original assignee: Individual
Current assignee: Individual
Priority date: 2012-10-02
Filing date: 2012-10-02
Publication date: 2014-04-09
Also published as: GB201217607D0

Abstract

A drilling fluid comprises ground up grape seed. The fluid may further comprise wetting additive, viscosifier and an activator or flocculant. Other plant material may also be incorporated with the grape seed e.g. Black Walnut or other nut hulls, cotton seeds or rice fractions. The fluid may be used to prevent fluid loss as a lost circulation material, as torque and drag reducing agent or as a proppant in fracturing and cleaning processes. One advantage is that grape seeds are a by-product of the wine producing industry which are bi-degradable and environmentally friendly.

Description

Statement of Invention -P' Application

1. Using Grape Seeds as an LCM Additive In the oil and gas industry "Lost Circulation Material" otherwise known as LCM has been uLilised almost since the beginning of Oil or Gas extraction. Several problems are encountered while drilling which encapsulate ( not limited tx) the total or partial loss of the drilling fluid in to permeable zones and seepage losses through micro fractnres. LCM is a composition of material which is used as a bridging or sealing agent to prevent fluid loss across these permeable or seepage zones and re-establish circulation returns at surface.

One method in mitigating fluid losses is by incoqxrating ground UI) grape seeds in the range of 10 to 750 microns with a wetting additive. viscosifier and a activator or flocculanL The ground up grape seeds can be utilised as part of the LCM conqxsition in fine, medium or course. Tius composition is dictated by the extent of the loss tone needing to be isolated.

This method of ground up grape seeds can he used in conjunction with any plant such 111cc material including not limited too) Black Wallnut or other nut hulls, cotton seeds, corn cobs or rice fractions. Water absorbeilt polymers, swellable fibers or friction reducing material can also he part of this comuhination. The desired LOYl incorporating the grape seeds composition can be added to the drilling fluid in a pill 111cc form or on a continuous basis depending on the loss type and severity. Grape seeds are biodegradable and environmentally friendly.

This can be better illustrated in diagram 1 on the next page:

Statement of Invention -2 Application

2.0 Using LCM Seeds as a Torque and Drag Reducing Agent and to mitigate differential sticking As well as ntilising grape seeds as a form of L('M in the drilling fluid, other applications are also available.

While drilling surface torque and drag, down hole stick sill) and differential sticking can also he a problem.

torque and Drag is limited to the rotational and pulling capability-of the rig or working unit. Ihis sometimes can result in not being able to drill and reach the rcqtnred oil or gas zone. Alternatives dne to this reason have to he made to change the rig specifications, well design or surface location which can he very expensive and even made the target reservoir uneconomical.

Stick and slip can also he a deciding factor on the Bottom hole Assemblies ( BIJA) capabilities while drilling. In this scenario the BRA components while drilling can experience severe torque in certain sections which if left nutreated could result in the BHA parting. Again resulting in serions expense to the overall well cost.

Differential sticking is also another main canse of concern in the drilling operation. While drilling if the drill string is left in the stationary position for prolonged periods of time, for example when making a connection.

If the permeable zone in contact with the drill string is at a lower hydrostatic pressure. after only a few tninutcs differcittial sticking can start to take place. This can result in the drill string hcitig stuck itt some cases being completely lost down hole. the well The speed at which this occurs is dependent on the time the string is stationary for and the snrfacc area of the drill string which is in contact with this permeable low pressure zone.

Here in all these scenarios, the Grape seeds can be injected down the drilling string out the bit atid circulated back up the wellbore to surface. The seeds will reduce the surface area of the drill stritig acling on the fortnation. This will assist in reducing torque attd drag at surfnce, stick attd slip down hole and the speed of which differential sticking takes place. These benefits will improve down hole drilling performance ( Rate of Peneiration) and mitigate BTIA failure arid differential sticking tendencies.

Specifically for Extended Reach Drilling or Wells contaitntig long horizontal sectiotts. This can be better illustrated in diagram 2 on the next page.

Statement of Invention -3rd Application

3.0 Using Crape Seeds in to the In(luce(l Fracturing Process Another application where grape seeds ca be encompassed is as a proppaut in the reservoir fracture and cleaning process. In iniperrucable formations where hydrocarbons are presert. Fractures are induced in desired productions zones in order to extract the Hydrocarbons. Once the fractures have been achieved a inedinm is injected down hole to ensure the fractures remain open. This allows production of tins zone to take place. The fractures can either he caused by means of explosives down hole or by the hydraulic medium itself -in either case this is ithown as induced fracturing. Regardless of which method is being utilisecl the grape seeds are itected in to the induced fractures which keep ttiem open and enable the formation to he more permeable. The well is then clean out in order to remove any ullwanted down hole debris which is then brought on to prodnction. This process can implemented several times across the desired productive interval as dictated by the Oil and Gas Operator.

This can he better illustrated in diagram 3 on the next page.

Advantacs of usinu Grave Seeds in the drillinu fluid 1. Grape seeds are cheap, biodegradable and environmentaliy friendly 2. Grape seeds can he grounded up to the required mesh size to obtain the correct TCM concentration ileeded to assist in curing the losses.

3. Grape seeds are recyclable and reusable, they can he collected at cnrface and re-injected down bole several times as needed 4. Grape seeds have a buoyancy factor heavier than water, so they can also be used as a weighting agent.

5. (kape seeds due to their natural size and shape can be used to reduce the surface area of the drill string and BHz iii contact with the wellbore wall thereby reducing surface torque and drag, stick and slip as well as differcnlial sticking down hole.

6. Grape seeds can he used to hold open induced fractures without harming the environment.

7. Grape seeds can easily be injected through bottom hole assemblies without plugging up or damaging the down hole eqnipment.