Modified Corn Starch as an Environmentally Friendly Rheology Enhancer and Fluid Loss Reducer for Water-Based Drilling Mud

Abstract

Summary Drilling fluid rheology and fluid loss property are fundamental parameters that dictate the effectiveness and easiness of a drilling operation. Maintaining these parameters under high temperatures is technically challenging and has been an exciting research area for the drilling industry. Nonetheless, the use of drilling mud additives, particularly synthetic polymers, threaten ecological environments. Herein, modified corn starch (MCS) was synthesized, characterized, and investigated as an environmentally friendly rheology enhancer and filtration loss controlling agent for water-based mud (WBM) at high temperatures. The experimental results indicated that MCS exhibits better performance in improving rheological properties and fluid loss controlling ability for WBM than the commonly used mud additives. With the addition of an optimal concentration (0.3 wt%), MCS improved the rheology and fluid loss behavior of WBM formulation at harsh aging temperature (220°C) by practically 4 times and 1.7 times, respectively. The MCS was revealed to perform superbly over polyanionic cellulose (PAC) addition at all investigated temperatures. The better performance of the MCS was ascribed to the improved entanglements in the mud system owing to the additional hydroxyl (OH) groups. Besides, the Herschel-Bulkley model was found to be a constitutive model that described the rheological properties of the investigated muds satisfactorily. Moreover, the MCS was found to exhibit acceptable biodegradability properties.

Dual Modification Approach for Tapioca Starch Using Gamma Irradiation and Carboxymethylation

“…This was followed by arti cial drying for 48 hours at 122 ℉. The starch was treated by gamma-irradiator (NORDION Cobalt 60 Irradiator Model: JS10000) at different doses of 25,35,45, and 60 kGy (100 rad = 1Gy). The dosage rate was maintained at 1kGy per 40 minutes.…”

Synthesis of novel zwitterionic polymers and their properties as filtrate reducer for water‐based drilling fluid

“…Commonly used filtrate reducers are mainly divided into natural modified polymers, nanomaterials and synthetic polymers, which are adsorbed on the surface of bentonite through physical actions such as hydrogen bonding and static electricity to optimize the particle size distribution of bentonite and improve the permeability of mud cake, thus reducing the filtration loss of WBDF 15 . Natural filtrate reducers such as modified cellulose, 16 starch, 17 xanthan gum 18 and lignin 19 are cheap and environmentally friendly, but they are widely used in shallow drilling operations because of their low applicable temperature. Nanomaterials such as silica have been widely studied, 20 and their rigidity and thermal stability can improve the performance of WBDF, 21 but the need for surface modification increases the additional cost.…”

Nano-Modified Polymer Gels as Temperature- and Salt-Resistant Fluid-Loss Additive for Water-Based Drilling Fluids

“…The common fluid loss reducers are mainly divided into two categories: natural/natural-modified polymers and synthetic polymers, which can optimize the particle size distribution of bentonite particles and reduce the permeability of mud cakes, thereby achieving the effect of reducing drilling fluid filtration [ 13 ]. Natural fluid loss additives, including humic acid, cellulose, lignin, starch, phenolic resin, etc., have been widely used in conventional formation drilling operations due to their vast sources and lack of environmental harm [ 14 , 15 , 16 , 17 , 18 , 19 , 20 ]. Nevertheless, due to a large number of ether–oxygen bonds (low bond energy) in the natural polymer molecular structure, its temperature resistance is poor (<150 °C), limiting its application in deep and ultra-deep wells.…”