Chemically Modification of Lignin Biopolymer and Chemically Modification of Lignin Biopolymer and its Industrially Application as a Hydrocarbon its Industrially Application as a Hydrocarbon

Drilling Well Additive Drilling Well Additive

Mohamed-Rashid Ahmed Mohamed HarasAssociate Professor. Dr. Mohamad Nasir Mohamad IbrahimAssociate Professor. Dr. Coswald Stephen Sipaut @ Mohd Nasri

In the course of drilling an oil or gas well by means of rotary drilling tools, a so called ( Drilling mud ) is circulated downwardly through the hollow drill stem and bit to the bottom of borehole and then upwardly to the surface through the annular space between the drill stem and the interior of the borehole.

The most common mud used in the drilling process is Bentonite due to; its mixed friendly with water and allow mud additives to perform efficiently. Beyond that, it is cheap.

During the drilling process, drilling mud is applied to the borehole through the drill pipe and back to the surface in order to achieve specific functional :

Cool and lubricate the bit and drill string.

Clean the bottom of the hole beneath the bit

Transport cuttings to the surface. Suspend drill cuttings in the annulus

when circulation is stopped. Drop off the cuttings at the surface. Support the walls of the borehole. Control subsurface pressure. Stabilize the borehole.

The main chemical functional groups in Kraft lignin are the hydroxyl, methoxyl, carbonyl groups (El Mansouri & Salvadó, 2007).

Such functional groups could open newer possibilities to expand the chemically modification process of lignin. This will enhance its applicability in many industrial aspects.

Preparation of Lignin Graft Copolymer

Preparation of Lignin Graft Copolymer

The water-based The water-based drilling muds with drilling muds with viscosity-building viscosity-building and suspension-and suspension-

carrying abilities carrying abilities for oilfield for oilfield

applications require applications require thermally stable thermally stable

water-soluble water-soluble polymers to control polymers to control the rheological the rheological

property of drilling property of drilling mudsmuds

DSC thermogram for the Lignin

No melting temperature Tm

or crystallization temperature Tc

has been recorded

DSC thermogram for Lignin Graft Copolymer

High Tg vlue:The bulkiness and the

reticulation of the phenolic groups in the lignin

structure.

Low Tg value:Hydrocarbon chain without bulky groups that gives PAA molecules enough space to move with more

flexibility.

KL has a rough surface with

shapeless configure and the granular structure can be observed (Bonini, D'Auria, Ferri, Pucciariello & Sabia, 2003).

Continues wavy

surface

Pores that could

facilitate the

penetration and enhance

the solubility

- Two values of temperatures were chosen in order to confirm whether the performance of LGC is consistent both at room and high temperature.

- The results obtained are used to highlights the importance of using the correct dosage of treatment for optimization performance of gelling agent and viscosifier as well as to save unnecessary cost.

- Table 1 shown the optimum dosage of LGC is 0.5 % which gave moderate viscosity, gel strength and yield point as well as sufficient pH value compared to others at both temperatures.

- In addition, the use of excessive or insufficient dosage may also bring out negative impact to the mud properties.

Types of Mud T AV PV YP GS pH

Brae-Based Mud 27 28 12 16.35 23 11.91

Base Mud + 0.3% LGC

27 32.50 11 21.97 75 10.49

Base Mud + 0.5% LGC

27 40.00 14 26.57 73 9.63

Base Mud + 0.7% LGC

27 45.00 15 30.66 67 7.45

Bare-Based Mud

90

30.50 15 15.84 31

11.82

Base Mud + 0.3% LGC

90 41.50 11 31.71 95 10.15

Base Mud + 0.5% LGC

90 40.50 11 30.14 76 9.20

Base Mud + 0.7% LGC

90 43.00 11 32.70 60 7.22

As a drilling mud takes place downwardly the drilling mud temperature tends to increase rapidly due to friction and this increase influences the mud rheological properties negatively.

The negative effect includes sever decrease of drilling mud viscosity and yield point and that makes most of drilling mud additives not functional at high temperature.

In this regard, a polymeric drilling mud additive with a higher yield point exhibits higher gel strength, which imparts a desirable structural property to the drilling mud (Gray & Darley, 1980).

Types of mud

AV PV YP

Before After Before After Before After

Base mud + 0.5% LGC 38 58.5 13 37 25.55 21.97

Base mud + 0.5 % CMC 97.5 25 19 18 61.8 7.154

Base mud + 0.5 % Guar Gum 105 23.5 35 18 71.5 5.621

Base mud + 0.5 % Xanthane 82.5 21 64 16 28.10 5.11

There are times when circulation has to be stopped, the drilling mud must have that gelling characteristics ( gel strength) that will prevent drill cuttings from settling down at the bit.

With proper thermally stable gel strength can help suspend cuttings in the hole and allow them to settle out on the surface.

A mud pH range between 9 and 10.5 is almost always desired in drilling operations. This range suppresses the corrosion rate of drilling equipment especially drill pipe and bit.

Types of mud

GS pH

Before After Before After

Base mud + 0.5% LGC 73 74 9.65 9.25

Base mud + 0.5 % CMC 96 14 11.62 9.30

Base mud + 0.5 % Guar Gum 79 7 11.53 8.73

Base mud + 0.5 % Xanthane 67 4 11.62 8.64

LGC has been successfully synthesized by exploiting the waste of palm oil industry in the polymeric field.

From an experimental point of view, the use of 0.5 % LGC as drilling mud additives is not required any additional additives like thermal stabilizer (alkyl metal chromate and starch) or pH controlling agent ( soda ash and acetic acid), thereby it may reduced the cost of drilling operation and minimize the environmental damage.

LGC exhibited good compatibility with commercial drilling mud additives in terms of ; viscosity building, gelling abilities, pH controlling and thermal degradation resistance.

thank YOU FOR YOUR KIND Attention