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Stability Evaluation of Surfactant-Grafted Polyacrylamide Used in Oilfields by Evolution of Ammonia  [PDF]
Tingting Jiang, Baohui Wang, Haiyu Wang
Journal of Materials Science and Chemical Engineering (MSCE) , 2014, DOI: 10.4236/msce.2014.25003

Surfactant-grafted Polyacrylamide (S-PAM) serves as a novel oil displacement agent in oilfield. The analysis on composition of S-PAM shows that due to its instability the harmful ammonia gas may be generated during the operation of S-PAM or high temperature. In this paper, stability of S-PAM was studied by measuring the ammonia release from solid and aqueous S-PAM at different temperatures. The results showed that ammonia release of the solid S-PAM was increased with raising temperature. The ammonia release from S-PAM produced by Haibo Company is more than one from Lianhua in the solid state. The ammonia emissions from Lianhua S-PAM are slightly higher than Haibo one in the solutions prepared by both clean water and oilfield water.

Study on Occupational Health and Safety Impact of Surfactant-Grafted Polyacrylamide Used in Oilfields  [PDF]
Tingting Jiang, Baohui Wang, Aijun Wang, Hongjing Han, Hongjun Wu
Occupational Diseases and Environmental Medicine (ODEM) , 2015, DOI: 10.4236/odem.2015.33006
Abstract: Surfactant-grafted Polyacrylamide (S-PAM) serves as a novel oil displacement agent in oilfield. Its toxicity and the impact on the occupational safety are unclear. The analysis on composition and chemical structure of S-PAM shows that due to its instability the harmful ammonia gas may be generated during the operation of S-PAM or high temperature. The toxicity and safety evaluation of the S-PAM were analyzed, and suggestions on the protection were proposed. It can provide a safe and healthy working environment for the operators with enormous social and economic benefits.
Analysis and Formation of Hazardous Substances from Surfactant-Grafted Polyacrylamide Powder for Oilfield Production  [PDF]
Tingting Jiang, Haiyu Wang, Baohui Wang
Open Journal of Applied Sciences (OJAppS) , 2014, DOI: 10.4236/ojapps.2014.49047
Abstract: Surfactant-grafted Polyacrylamide (S-PAM) serves as a kind of economical and efficient flooding agents for its single component in the enhanced oil recovery in Daqing oilfield in China. The oil displacement experiments using S-PAM in multi-blocks revealed that in-use S-PAMs differ greatly from ordinary polymers. Aiming at making clear hazardous substances of S-PAM powder, this study characterized two commonly used S-PAMs in oil field through chemical analysis and instrumental analysis, and analyzed the toxic and hazardous gases of the two S-PAM powders.
Experimental Study on the Properties and Displacement Effects of Polymer Surfactant Solution  [PDF]
Ke-Liang Wang,Lei-Lei Zhang,Xue Li,Yang-Yang Ming
Journal of Chemistry , 2013, DOI: 10.1155/2013/956027
Abstract: Based on the characteristics of oil reservoirs and the requirements of further enhancing oil recovery at high water cut stage of Pubei Oilfield, the displacement performance of polymer surfactant is evaluated. Reasonable injection parameters and oil displacement effects after water flooding are also researched. Compared with conventional polymer with intermediate molecular weight, polymer surfactant has the properties of higher viscosity at low concentration condition and lower interfacial tension. Laboratory experiments indicate that the displacement effect of polymer surfactant is much better than that of conventional polymer at a slug size of 0.57?PV. The oil recovery of polymer surfactant increases by more than 10% after water flooding. Considering the actual situation of low-permeability of Pubei Oilfield reservoirs, the system viscosity of 30?mPa·s is chosen. The corresponding concentration of Type III polymer surfactant is 600?mg/L and the injected slug is 0.57?PV and the oil recovery can be increased by 11.69%. 1. Introduction Polymer flooding has already entered the industrial application period in major reservoirs of Daqing Oilfield, and pilot trial has also been conducted in Pubei Oilfield, one of the many oilfields of Daqing Oilfield. Both laboratory and field data have shown that polymer flooding could improve oil recovery by nearly 10%, but this value was not perfect [1]. It was indicated that the oil recovery of ASP flooding was 20% higher than that of water flooding in Daqing Oilfield pilot tests [2, 3]. However, some problems such as formation damage due to alkali scale, production well pollution, and effluent treatment difficulties appeared in ASP development process [4, 5]. Experimental results showed that the oil recovery of binary combination flooding in major reservoirs increased by more than 15% [6]. However, the adsorption, diffusion, and migration properties of different chemical agents in porous media are quite different. This difference may result in the phenomenon of chromatographic separation and negative synergistic effect during the mixture system simultaneous flow [7]. In recent years, some functional groups have been grafted to hydrocarbon main chains to form a multivariate graft copolymer which is called functional polymer surfactant (also referred to as polymer surfactant) [8, 9]. As a new type of polymer, polymer surfactant is a single component oil displacement agent. In addition to the general nature of polymer, polymer surfactant can improve solubilization and emulsification capacity of crude oil in the absence of
Scaling Analysis of Surfactant Templated Polyacrylamide Gel Surfaces  [PDF]
Mukundan Chakrapani,S. J. Mitchell,D. H. Van Winkle,P. A. Rikvold
Physics , 2001,
Abstract: Surfaces of surfactant-templated polyacrylamide hydrogels were imaged by atomic force microscopy (AFM), and the surface morphology was studied by numerical scaling analysis. The templated gels were formed by polymerizing acrylamide plus a cross-linker in the presence of surfactants, which were then removed by soaking in distilled water. Gels formed in the presence of over 20% surfactant (by weight) formed clear, but became opaque upon removal of the surfactants. Untemplated gels formed and remained clear. The surface morphology of the gels was studied by several one- and two-dimensional numerical scaling methods. The surfaces were found to be self-affine on short length scales, with a roughness (Hurst) exponent in the range 0.85 to 1, crossing over to a constant root-mean-square surface width on long scales. Both the crossover length between these two regimes and the saturation value of the surface width increased significantly with increasing surfactant concentration, coincident with the increase in opacity. We propose that the changes in the surface morphology are due to a percolation transition in the system of voids formed upon removal of the surfactants from the bulk.
Comparative Study of Physical Properties of In-Use Surfactant-Grafted Polyacrylamides for Oilfield  [PDF]
Tingting Jiang, Haiyu Wang, Baohui Wang
Open Journal of Physical Chemistry (OJPC) , 2014, DOI: 10.4236/ojpc.2014.43016

Surfactant-grafted Polyacrylamide (S-PAM), as a new type of oil displacement agent in oilfield, integrates the advantages of both polymer and surfactant. The oil displacement experiments using S-PAM in multi-blocks reveal that in-use S-PAMs differ greatly from ordinary polymers and the physical properties remain unclear. This is unfavorable to production application and occupational health and safety. This research compared the physical properties of S-PAMs selected from two producing area, including specific gravity, particle size and viscosity. The compared results showed that specific gravity of Lianhua S-PAM was smaller than Haibo S-PAM; Lianhua S-PAM and Haibo S-PAM accounted for the 93.8% and 80.1% of the total amount via the particles with 40 mesh and 60 mesh; the viscosity of Lianhua S-PAM was higher than that of Haibo S-PAM in two S-PAM solutions with different concentrations.

Journal of Engineering Science and Technology , 2009,
Abstract: Grafted anionic polyacrylamide gel has been synthesised in the laboratory following radical polymerisation process. Kinetics of thermal degradation of synthesised gel was evaluated under nonisthothermal condition by integral approximation method to determine the thermal stability of the material from thermogavometric study. The activation energy for the thermal degradation was found to be significantly high for the gel material.
Mahnaz Mahdavi,Mansor B. Ahmad,Md Jelas Haron,Mohamad Zaki Ab Rahman
BioResources , 2011,
Abstract: Cr(III) ions were adsorbed onto polyacrylamide-grafted rubberwood fibre, and effects of aqueous conditions were evaluated. The adsorbent was prepared via graft copolymerization of acrylamide (Am) onto rubberwood fibre (RWF), using ceric ammonium nitrate as an initiator. Fourier transform infrared spectroscopy was used to confirm the formation of PAm-g-RWF. Various variables affecting the adsorption capacity such as the pH of the solution, adsorption time, initial metal ion concentration, and temperature were investigated. The Cr(III) was up to 92% removed by PAm-g-RWF from an initial concentration of 10 mg/L at pH 5.0. Kinetic data fitted very well to a pseudo-second-order rate expression and less well to a pseudo-first-order equation. The equilibrium parameters for adsorption isotherms of the metal ions on the grafted fibre were obtained using Langmuir and Freundlich models, and the Langmuir model was found to be in better correlation with the experimental data with a maximum adsorption capacity of 18.24 mg/g. Thermodynamic parameters such as enthalpy change (ΔH°), free energy change (ΔG°), and entropy change (ΔS°) were calculated; the adsorption process was spontaneous and endothermic.
Water-Soluble and Biodegradable Pectin-Grafted Polyacrylamide and Pectin-Grafted Polyacrylic Acid: Electrochemical Investigation of Corrosion-Inhibition Behaviour on Mild Steel in 3.5% NaCl Media  [PDF]
R. Geethanjali,A. Ali Fathima Sabirneeza,S. Subhashini
Indian Journal of Materials Science , 2014, DOI: 10.1155/2014/356075
Abstract: Pectin-g-polyacrylamide (denoted as Pec-g-PAAm) and pectin-g-polyacrylic acid (denoted as Pec-g-PAA) were synthesized using pectin, acrylamide, and acrylic acid as starting materials. The grafted polymers were characterized using Fourier transform infrared spectroscopy (FTIR), thermogravimetric analyser (TGA), and scanning electron microscopy (SEM). The corrosion inhibition behaviour of the grafted polymers on mild steel in 3.5% NaCl was evaluated electrochemically through Tafel polarization and impedance studies. The corrosion inhibition performance of both the polymers was found to be around 85%. 1. Introduction The importance of mild steel is well known owing to its cost, process-ability, and weld-ability when used for infrastructures in marine environments like ship hulls, oil rings, off-shore platforms, coastal facilities and sheet piling, and so forth. The mild steel is preferred over stainless steel in chloride environments, because the cost of stainless steel good enough to resist corrosion is far too great. There are several advantages in selecting the mild steel, but it still suffers uniform or generalised corrosion, which is of considerable economic importance. The corrosion inhibition mechanism involves strong adsorption of inhibitor molecules on the active sites of metal and thereby preventing cathodic and anodic reactions of the metal. Polymers are selected for corrosion inhibition because of the superior performance when compared with their monomer analogues in active adsorbing on the corrosive sites of the metal [1]. The improved performances of the polymeric materials are ascribed to their multiple adsorption sites for bonding with the metal surface. The polymer provides two advantages: a single polymeric chain displaces many water molecules from the metal surface, thus making the process entropically favourable and the presence of multiple bonding sites makes the desorption of the polymers a slower process [2]. Research activities in recent times are geared towards revealing green corrosion inhibitors to replace the toxic inorganic and organic compounds. Naturally occurring substances have been found to readily satisfy this need. Apart from being readily available, cheap, and a renewable source of materials, naturally occurring substances are eco-friendly and ecologically acceptable [3]. Xu et al. [4] synthesized polyaspartic acid-melamine (PASPM) grafted copolymer and evaluated its CaCO3 and Ca3(PO4)2 scale inhibition performance and dispersion capacity for ferric oxide. The PASPM copolymer efficiently inhibited CaCO3 scale and
Breaking of Oil -Water Emulsion for the Improvement of Oil Recovery Operations in the Niger Delta Oilfields  [PDF]
C. Ijogbemeye Oseghale,Akpabio E. J,Udottong, G
International Journal of Engineering and Technology , 2012,
Abstract: Emulsified water is generally present in crude oil as a result of mixing occurring during production operations. The formation of emulsion leads to problems in production and also transportation. Therefore the need to break oil/water emulsions system through demulsification process using chemical surfactants for improved oil recovery operations. Selected cationic surfactants were effective in separating oil-water emulsions expected during a surfactant/polymer (SP) process for improved oil recovery. The aqueous phase of the emulsion contained an anionic surfactant blend, alcohol and partially hydrolyzed polyacrylamide. Brine composition was a suitable mixture of formation brine with brine from polymer drive. The crude oil had an API gravity of 47.2. Bottle tests were conducted at ambient temperature, which is near the reservoir temperature. Both oil and water phases of acceptable quality were obtained after settling upon addition of 200ppm of octytrimethylammonium bromide (C8TAM) at ambient temperature. Microscopy image showed significant coalescence after only 1 minute in C8TAM system as the cationic surfactant reduced electrostatic repulsion among drops and shifted system behavior towards the balanced state between hydrophilic and lipohilic effect well-known to reduce emulsion stability. The amount of cationic surfactant may be reduced by reduced by adding it simultaneously with anionic demulsifier resin.
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