Abstract Polyacrylamide-co-sodium acrylate has been prepared via copolymerization of acrylamide and acrylic acid, or the hydrolysis of a pre-formed nonionic polymer. Both macromolecules had a charge of 24 mol% with a molar mass of 25 million g/mol. While one might expect similar performance, the hydrolyzed materials were superior in rheology modification, while the copolymerized samples worked better as flocculants. This hydrolysis reaction is influenced by the dyad sequence and produced a relatively uniform charge distribution along the backbone. These partially hydrolyzed polyelectrolytes ha ..read more

Abstract As a vital technology for ensuring the stable operation of industrial equipment, fault diagnosis has received a lot of research in recent years. Most complex industrial processes are in normal working conditions during operation, so the amount of data collected under normal working conditions is much larger than that under fault working conditions. The uneven number of samples will lead to the imbalance of datasets and make it a challenging task to assure the overall accuracy. To address the issue, an innovative imbalanced fault diagnostic approach based on area identification conditi ..read more

Abstract Electrocoalescence is widely used to dehydrate crude oil, but impurities in crude oil are extremely complex, which greatly weaken the effect of dehydration. To understand the coupling law of various impurities, a static demulsification experiment was conducted under a high frequency and high voltage pulsed electric field to investigate the effects of electric field parameters (voltage, frequency, pulse width ratio), emulsification strength, electrocoalescence time, water content, acid value, injection alkali ratio, calcium content, decalcification agent concentration and removal proce ..read more

Kinetic modelling and validation of biomass pyrolysis process. Abstract Biomass pyrolysis process from a drop tube reactor was modelled in a plug flow reactor using Aspen Plus process simulation software. A kinetic mechanism for pyrolysis was developed considering the recent improvements and updated kinetic schemes to account for different content of cellulose, hemicellulose, and lignin. In this regard, oak, beechwood, rice straw, and cassava stalk biomasses were analyzed. The main phenomena governing the pyrolysis process are identified in terms of the characteristic times. Pyrolysis proces ..read more

Controlling the catalyst synthesis yields an optimized Ag/Al2O3 catalyst with broad temperature window of activity for NOx SCR using propylene (HC-SCR). Abstract Ag/γ-Al2O3 is an effective catalyst for the selective reduction of NOx (SCR) using propylene as a reducing agent. The catalyst performance is greatly influenced by the synthesis procedure. Various methods for synthesis of Ag/γ-Al2O3 are analyzed, and their performance is examined via packed bed reactor experiments in this work. An optimal one-pot synthesis method, single-step sol–gel (SSG) synthesis, is explored systematically. The ..read more

Abstract Ce-promoted Ni catalysts were developed and applied in a CO methanation reaction. The 10%Ni/SiO2 catalyst exhibits poor initial CO conversion (32.8%) and rapid deactivation with the highest methane selectivity during CO the methanation reaction. In contrast, the 4%Ce–10%Ni/SiO2 catalyst shows dramatically increased initial CO conversion, which is up to 90.7%. Additionally, the apparent activation energy, Ea value, of 4%Ce–10%Ni/SiO2 was calculated to be 102.2 kJ/mol according to the Arrhenius equation, which is much lower than that of the 10%Ni/SiO2 catalyst, which was 139.1 kJ/mol. B ..read more

Abstract This study aims to develop an industrially reliable and accurate method to estimate crude oil properties from their Fourier transform infrared spectroscopy (FTIR) spectra. We used the complete FTIR spectral data of selected crude oil samples from seven different Canadian oil fields to predict 10 important crude oil properties using artificial neural networks (ANNs). The predicted properties include specific gravity, kinematic viscosity, total acid number, micro carbon content, and production of light and heavy naphtha, Kero, and distillate in oil refineries. The 107 different (65 ligh ..read more

Abstract The presence of particles in oil can change the quasi-sequence structure of the turbulent flow of the oil, and it is extremely important to explore the turbulent energy dissipation rate of the particulate-containing oil and ensure the safe and stable operation of the oil-using equipment. Thus, the flow field of the oil containing particles in the pipeline was experimentally studied by a particle image velocimeter (PIV); the turbulent kinetic energy of the oil was calculated using the transient velocity vector field measured by the PIV; and the dissipation rate distribution was calcula ..read more

Abstract The drying characteristics of sludge in a uniaxial vacuum disc dryer are numerically studied in the present study, and the results showed that the drying process of sludge includes three stages: the viscous stage, the sticky stage, and the granular stage. The influence of main parameters such as sludge feeding rate, heat source temperature, and rotating speed of the shaft on the drying process of sludge in the uniaxial vacuum disc dryer is analyzed. In order to optimize the drying efficiency of the dryer, a differential push-flow structure is proposed in this study, which provides dif ..read more

Abstract In this paper, we have developed an integrative method for checking the stability of linear time-invariant (LTI) systems as well as nonlinear continuous-time ones. In our method, we first apply the iterative Faddeev–Leverrier algorithm to obtain the characteristic polynomial of the LTI system. Subsequently, the associated Hermite-Fujiwara matrix will be evaluated by a particularly efficient technique for the calculation of the Bézoutian matrices. The positive-definiteness of the Hermite-Fujiwara form, as the stability criterion, is next tested by performing the Cholesky decomposition ..read more