Deep Penetration Resin Systems Overcome Annular Gas Migration: Case History

Well Integrity is a critical compliance requirement during oil and gas operations. Abandonment procedures must ensure that all hydrocarbon sources are properly isolated and effective barriers are placed. This paper describes the use of resin systems to isolate annular gas migration identified during the Obiwan – 1 well abandonment in Colombia. The main challenge was to select and design fluid systems capable to fill tight spaces and isolate the annular channel. Resin systems are high-strength, elastic polymers which act as dependable barriers to isolate fluid flow. They can be designed as a solid-free, pure liquid or may contain solids (cement with a formulated percent of resin). Solid-free formulations are ideal for remedial operations, such as isolating annular gas. Acoustic logging enabled identification of the influx zones. Annular isolation was achieved by executing two cementing remedial operations using the bradenhead squeeze technique. A tailored resin system was selected to deliver the proper barrier addressing the influx zones after injectivity tests were performed in each interval. For the first intervention a solids-free resin system was used, and for the second one a resin-cement composite system was applied. During cementing remedial operations, it was determined that the resin systems were able to achieve deep penetration into the channels more readily and form a seal. The correct system was selected for each case, and during execution, the required volume was injected to intersect and properly isolate the annular gas channel. As a result, the tailored resin systems isolated the gas channel eliminating annular pressure and gas migration to surface. In addition, a post remedial operation acoustic log indicated that the influx zones were successfully isolated. Well abandonment was accomplished according to country regulatory requirements and delivered dependable barriers both annular and interior pipe sections. Use of resin to repair channels of this type exhibited a higher success rate and improved reliability in comparison to conventional particulate-laden fluids, which helps to decrease costs for additional remedial treatments.

Preparation, morphology, FTIR and performance properties of foaming particleboard

The application of light weight particleboard in furniture industry becomes more inevitable because of the requirement to facilitate transportation and assembly by the customer. Herein, a novel method for the fabrication of foaming particleboard was proposed, which is achieved by adding azodicarbonamide (AC) foaming agent into the formulation that consist of oven-dry poplar (Populus alba) particles (with the moisture content about 4%) and phenol formaldehyde resin (PF resin) (solid content of 48%). In this study, the effects of AC foaming agent and adhesive contents incorporation and its content on mechanical, physical and chemical properties of particleboards were investigated. The results showed that the addition of AC foaming agent played a critical role in properties of particleboard and the optimal particleboard performance was achieved at the particleboard density of 0.6 g/cm3, the PF resin amount of 12%, and the AC foaming agent amount of 1%. Furthermore, the pores appeared on the particle surface were the products of the radical pyrolysis of the foaming agent, which has been proved by the FTIR results and the pores also affect the properties of the particleboards.

Fabrication of Water-Compatible Molecularly Imprinted Resin in a Hydrophilic Deep Eutectic Solvent for the Determination and Purification of Quinolones in Wastewaters

A novel water-compatible molecularly imprinted resin was prepared in a green solvent deep eutectic solvent (DES). Resorcinol and melamine, as functional monomers with an abundant hydrophilic group, such as –OH, –NH2 and –NH–, were introduced into the molecularly imprinted resin (MIR). Three DESs (choline chloride-ethylene glycol, tetramethylammonium bromide-ethylene glycol and tetramethylammonium chloride-ethylene glycol) were used to synthesize the molecularly imprinted resin and the resulting deep eutectic solvent-based molecularly imprinted resins were characterized by particle size analysis, elemental analysis, scanning electron microscopy, Fourier transform infrared spectroscopy and thermogravimetric analysis. The resulting deep eutectic solvent-based molecularly imprinted resins were then applied to the adsorption of quinolones (ofloxacin) in water. The adsorption process of deep eutectic solvent-based molecularly imprinted resin followed the static adsorption model, Langmuir isotherm (R2 ≥ 0.9618) and kinetic model pseudo-second-order (R2 > 0.9814). The highest theory adsorption ability of the three kinds of deep eutectic solvent-based molecularly imprinted resins was more than 23.79 mg/g. The choline chloride-ethylene glycol-based MIR was applied to solid-phase extraction for the determination and purification of quinolones (e.g., ciprofloxacin and ofloxacin). The detection limit of deep eutectic solvent-based molecularly imprinted resin-solid-phase extraction method was less than 0.018 mg/L. The recoveries of the deep eutectic solvent-based molecularly imprinted resin-solid-phase extraction method at three spiked levels were 88.7–94.5%, with a relative standard deviation of ≤4.8%. The novel deep eutectic solvent-based molecularly imprinted resin-solid-phase extraction method is a simple, selective and accurate pre-treatment method and can be used to determine the quinolones in environmental water.