Foaming Ability Research Articles

Modeling Microscale Foam Propagation in a Heterogeneous Grain-Based Pore Network with the Pore-Filling Event Network Method

Foam flooding is an efficient and promising technology of enhanced oil recovery that significantly improves sweep efficiency of immiscible displacement processes by providing favorable mobility control on displacing fluids. Although the advantages in flexibility and efficiency are apparent, accurate prediction and effective control of foam flooding in field applications are still difficult to achieve due to the complexity in multiphase interactions. Also, conventional field-scale or mesoscale foam models are inadequate to simulate recent experimental findings in feasibility of foam injection in tight reservoirs. Microscale modeling of foam behavior has been applied to further connect those pore-scale interactions and mesoscale multiphase properties such as foam texture and the relative permeability of foam banks. Modification on a microscale foam model based on a pore-filling event network method is proposed to simulate its propagation in grain-based pore networks with varying degrees of heterogeneity. The impacts of foam injection strategy and oil-weakening phenomena are successfully incorporated. Corresponding microfluidic experiments are performed to validate the simulation results in dynamic displacement pattern as well as interfacial configuration. The proposed modeling method of foam propagation in grain-based networks successfully captures the effects of lamellae configurations corresponding to various foaming processes. The results of the simulation suggest that the wettability of rock has an impact on the relevance between reservoir heterogeneity and the formation of immobile foam banks, which supports the core idea of the recently proposed foam injection strategy in tight oil reservoirs with severe heterogeneity, that of focusing more on the IFT adjustment ability of foam, instead of arbitrarily pursuing high-quality strong foam restricted by permeability constraints.

Experimental Study on Enhanced Oil Recovery Effect of Profile Control System-Assisted Steam Flooding.

Steam flooding is an effective development method for heavy oil reservoirs, and the steam flooding assisted by the profile control system can plug the dominant channels and further improve the recovery factor. High-temperature-resistant foam as a profile control system is a hot research topic, and the key lies in the optimal design of the foam system. In this paper, lignin was modified by sulfonation to obtain a high-temperature-resistant modified lignin named CRF; the foaming agent CX-5 was confirmed to have good high-temperature foaming ability by reducing the surface tension; the formula of the profile control system (A compound system of CRF and CX-5, abbreviated as PCS) and the best application parameters were optimized by the foam resistance factor. Finally, the effect of PCS-assisted steam flooding in enhanced oil recovery was evaluated by single sand packing tube flooding, three parallel tube flooding, and large-scale sand packing model flooding experiments. The results show that CX-5 has a good high-temperature foaming performance; the foam volume can reach more than 180 mL at 300 °C, and the half-life is more than 300 s. The optimal PCS formulation is 0.3 wt% CRF as an oil displacement agent + 0.5 wt% CX-5 as a foaming agent. The optimal gas-liquid ratio range is 1:2 to 2:1, and the high pressure and permeability are more conducive to the generation and stability of the foam. Compared with steam flooding, PCS-assisted steam flooding can improve oil recovery by 9% and 7.9% at 200 °C and 270 °C, respectively. PCS can effectively improve the heterogeneity of the reservoir, and increase the oil recovery of the three-parallel tube flooding experiment by 28.7%. Finally, the displacement results of the sand-packing model with large dimensions show that PCS can also expand the swept volume of the homogeneous model, but the effect is 9.46% worse than that of the heterogeneous model.

Effects of endogenous lipid on the functional qualities of tuna protein during cold storage

The effects of endogenous lipid on the quality of tuna protein during storage was evaluated. Defatted tuna protein was prepared and co-stored with different contents of tuna oil or soybean oil, and the functional qualities, oxidation, protein structure and lipid oxidation were compared. During storage, a higher tuna oil content caused a greater attenuation in the functional qualities of protein, including emulsifying, foaming and water absorption abilities, and tuna oil could lead to more severe attenuation than soybean oil. Besides, the higher the oxidation degree of oil, the higher the oxidation degree and the more disordered of sarcoplasmic and myofibrillar proteins, which indicated that protein oxidation could be induced by lipid oxidation and cause greater structural damage. Finally, Pearson correlation revealed that variation in myofibrillar protein more strongly affects the functional qualities than sarcoplasmic protein. Therefore, the removal of endogenous lipid had a significant positive impact on the quality stability of protein products during storage, especially for marine protein products.

Preparation, structural characterization and functional properties of a novel selenium chelating peptide derived from the hydrolyzate of wheat protein

ABSTRACT Organic selenium has been widely studied for its ability to better fulfill the physiological functions of selenium. In this study, a novel organic selenium (wheat protein hydrolyzate chelated selenium, WPH-Se) was prepared by chelating the hydrolyzate of wheat protein hydrolyzed by alkaline protease (WPH) with selenium, its preparation process was optimized; and structural and functional properties were investigated. The results showed that the highest selenium content of 10.97 mg/g was obtained in the chelate under the optimal conditions (peptide/selenium mass ratio 2:1, temperature 80°C, pH 8, time 60 min). UV-Vis, FTIR, DSC and SEM provided more information for the characterization of WPH-Se. During the chelating process, selenium ions might be effectively bound to WPH through carboxyl, carbonyl and amino ligands, and the C=O bond and -NH, -OH groups might be the sites. At different pHs, the solubility of WPH-Se was generally lower than that of WPH, which reached a maximum of 32.69% at pH 6. The EAI of WPH-Se was higher than that of WPH, which reached a maximum of 0.84 m2/g, and the ESI reached a maximum of 47.3 min at pH 10. The free sulfhydryl content of WPH-Se was greater than that of WPH, which reached a maximum of 12.78 μmol/g at pH 8. WPH-Se was superior to WPH in terms of foaming ability and emulsification properties. WPH-Se contained a certain amount of aromatic amino acids (7.962%) and a relatively high amount of hydrophobic amino acids (38.490%), and had high nutritional value. Wheat protein peptide chelated selenium would be a useful functional additive, this study would provide data to support further research and application of selenium dietary supplements.

Enhancement effect of β-Alumina nanoparticle concentration on foam thermal stability of the mixture of Fluorocarbon/Hydrocarbon surfactants

Nanoparticle-stabilized foams have a potential prospect used as new environmentally-friendly firefighting foams. The thermal stability of firefighting foam is a significant ability to resist on thermal radiation from flame. In the present study, the mixed dispersions of foams consisting of β-Al2O3 nanoparticles, hydrocarbons (APG-0810), and fluorocarbon surfactants (FS-50), are prepared. The basic properties, including foaming ability and foam drainage at room temperature of the mixed dispersions, are investigated. The foam stability under thermal radiation is evaluated. The results reveal that the presence of β-Al2O3 nanoparticles increases the conductivity and viscosity of the mixed dispersions, while the surface tension and foaming ability of the mixed dispersions first decreases and then increases with increasing β-Al2O3 nanoparticle concentration. The addition of β-Al2O3 nanoparticles significantly retards foam drainage and improves foam stability at room temperature. Also, the foam thermal stability can be effectively improved by the presence of incorporation of β-Al2O3 nanoparticles. The results can provide a basis for the application of β-Al2O3 nanoparticles in the development of POPs-free firefighting foams.

Characterization and Molecular Dynamics Simulation of a Lipase Capable of Improving the Functional Characteristics of an Egg-Yolk-Contaminated Liquid Egg White.

Lipase has great application potential in hydrolyzing residual yolk lipid in egg white liquid to restore its functional properties. In this study, a lipase gene from Bacillus subtilis was expressed in E. coli BL21 (DE3) and named Lip-IM. Results showed that although Lip-IM has stronger specificity for medium- and short-chain substrates than long-chain substrates (C16, C18), due to its excellent enzyme activity, it also has strong hydrolysis activity for long-chain substrates and maintained over 80% activity at 4-20 °C, but significantly reduced when the temperature exceeds 40 °C. The addition of 0.5% Lip-IM enhanced foaming ability by 26% (from 475 to 501%) and reduced liquid precipitation rate by 9% (from 57 to 48%). Furthermore, molecular dynamics (MD) simulations were run to investigate the conformational stability of Lip-IM at different temperatures. Results showed that Lip-IM maintained a stable conformation within the temperature range of 277-303 K. Fluctuations in the flexible area and backbone movement of proteins were identified as the main reasons for its poor thermal stability.

Formulation and evaluation of herbal shampoo

Background: Now-a-days many synthetic, herbal, medicated and non - medicated shampoos are available in the market but popularity of herbal shampoo among consumers is on rise because of their belief that these products being of natural origin are safe and free from side effects. Aim: The present study is aimed to formulate and evaluate the polyherbal shampoo in comparison with commercial shampoo. Preparation of herbal shampoo: To formulate a clear shampoo base, three samples, designated as F1, F2 and F3 were prepared by using Solanum Pubescens leaves, Achyranthus aspera roots as main ingredients. Results: The formulation F3 and dove have good foaming ability. No significant difference was observed in terms of odor and foaming ability between F3 Dove. The pH of F1, F2 and F3 was found to be 5.0, 5.4, and 6.2. The percent solid contents of F1, F2 and F3 and dove was found within the range of 22 to 25%. Viscosity of F1, F2 and F3 and dove was found to be 60, 61, 65 and 67 cps. F1, F2 and F3 and Dove showed similar reduction in surface tension ranging from 31.00 to 39.00 dyn/cm. The wetting time of F1, F2 and F3 and dove was found to be 195, 190, 178, 170 seconds. The F3 and Dove was shown foam volume as 85, 90, 98 and 110ml. Accelerated stability tests showed that no significant change over a period of time (3 months) for F3. Conclusion: In conclusion, the results showed that F3 had no significant difference in comparison to reference shampoo regarding their physicochemical properties and their Invitro evaluation.

Environmentally friendly tea saponin foam detergents costabilized by GO-OH/SiO2 nanoparticles for removing radioactive surface contaminants

Currently, bare silica nanoparticles with low surface activity and weak stabilizing foam ability have restricted applicability in treating surface radioactive pollutants. To address potential issues with SiO2 as a foam stabilizer, a highly efficient foam stabilizer was fabricated by compounding silica with hydroxylated graphene oxide (GO-OH), which was prepared by hydrothermal modification of graphene oxide (GO). Then, an environmentally friendly foam detergent with high stability and high decontamination efficiency was developed using the natural surfactant tea saponin (TAS) as a foaming agent and a composite of silica and GO-OH (GO-OH/SiO2) as a foam stabilizer, which is named tea saponin foam detergent. For different types of surfactants, the structural and morphological characteristics of GO-OH, such as hydrophilic and surface oxygen groups, as well as the synergistic influence of GO-OH with SiO2 on foamability, foam stability, and detergency of the foam detergent, were studied. As a consequence, the TAS foam detergent has good stability with a drain half-life of 68 min. By hydrothermal modification of GO, the contact angle of water on GO-OH in air dropped to 63.2°, which was lower than that (73.0°) on GO. Furthermore, the hydrophilicity of GO-OH increased, and more oxygen-containing groups on GO-OH enhanced its absorption and enrichment of the radionuclide uranium and improved the decontamination rate of the TAS foam detergent. Moreover, when GO-OH was combined with SiO2, the dispersion and stability of SiO2 in the foam detergent improved, and the foam stability of the detergent subsequently further improved. Adding 2 wt% SiO2 and 0.1 wt% GO-OH to the detergent enhanced the foam drainage half-life of the detergent from 40 min to 68 min and improved the stability of the detergent by 70%. In addition, the synergistic action of GO-OH/SiO2 with TAS surfactant increased the liquid film thickness of the foam and the airflow resistance to support the weight-bearing capacity of the foam skeleton. As a result, it slowed the rate of foam disproportionation, reduced the bubble size, increased the bubble number, and finally improved the foam stability of the detergent. For simulated radioactive uranium pollutants on the surfaces of glass, stainless steel, and tiles, the foam detergent with the synergistic action of GO-OH/SiO2 and TAS surfactant had decontamination rates of 91.7%, 91.16% and 91.76%, respectively, which were 14.96%, 15.67% and 19.39% higher than that of TAS foam detergent without GO-OH/SiO2. The synergistic enhancement of GO-OH and SiO2 on foam stability and its adsorption and combination action with uranyl ions would be the main reasons to improve the detergency of the TAS foam detergent. Therefore, TAS foam detergent stabilized synergistically by GO-OH/SiO2 with high stability and efficient decontamination will be widely applied in nuclear emergencies and decommissioning decontamination of nuclear facilities.

The Effect of Multiple Cycles of Surfactant-Alternating-Gas Process on Foam Transient Flow and Propagation in a Homogeneous Sandstone

Summary Years of laboratory studies and field tests show that there is still uncertainty about the ability of foam to propagate deep into a reservoir. Many factors have been identified as potential causes of nonpropagation, the most concerning being the lack of sufficient pressure gradient required to propagate foam at locations far from the point of injection. Most researchers that investigated foam propagation did so by coinjecting surfactant and gas. Coinjection offers limited information about transient foam processes due to limitations in the experimental methods needed to measure foam dynamics during transient flow. Foam injection by surfactant-alternating-gas (SAG) has proven to be more effective and common in field application. Repeated drainage and imbibition cycle offer a more favorable condition for the quick generation of foam. Foam can also be propagated at a lower pressure gradient in SAG mode. The objective of this study is to experimentally investigate how transient foam dynamics (trapping, mobilization, and bubble texture) change with multiple cycles of SAG and also with distance from the point of injection. A pair of X-ray source and receiver, differential pressure transducers, and electrical resistance sensors were placed along a 27-cm long, homogeneous, and high-permeability (KL = 70 md) Berea sandstone core. Foam was then generated in situ by SAG injection and allowed to propagate through the core sample under a capillary displacement by brine (brine injection rate = 0.5 cm3/min, Nca = 3×10-7). By use of a novel analytical method on coreflood data obtained from axial pressure and saturation sensors, we obtained trapped foam saturation, in-situ foam flow rates, apparent viscosities, and inferred qualitative foam texture at different core sections. We then observed the following: (i) Maximum trapped foam is uniform across the core sections, with saturation ranging from 47% to 52%. At the vicinity of foam injection, foam apparent viscosity is dominantly caused by gas trapping. At locations farther away, foam apparent viscosity is dominated by both gas trapping and refinement of foam texture. (ii) Cyclic injection of foam further enhances the refinement of foam texture. (iii) Textural refinement increases foam apparent viscosity as it propagates away from the point of injection. (iv) As the foam strength increases, the average gas flow rate in the core sample decreases from 0.5 cm3/min to 0.06 cm3/min. (v) There is no stagnation of foam as remobilization of trapped gas occurs during each cycle at an average flow rate of 0.002 cm3/min.

Properties and structural features of native and modified proteins of concentrates from white and brown rice

The physicochemical properties and structural features of proteins of concentrates (PC) from white and brown rice are described. Differences in a degree of proteolysis and the relationship between the functional and technological properties of proteins and their structure were established. Proteins from white rice had lower molecular weights (MW) than proteins from brown rice: 1.3–199.5 kDa versus 1.5–251.1 kDa. Most proteins were grouped in three low-molecular-weight fractions (МW 11.7–27.5 kDa) in PC from white rice and in one fraction with the high molecular weight (182–251.1 kDa) in PC from brown rice. In the process of hydrolysis, the MW of proteins (high-molecular-weight) of PC from white rice decreased from 199.5 to 120.2 kDa with generation of peptides with a molecular weight of <1.3 kDa, while the MW remained unchanged upon hydrolysis of proteins of PC from brown rice. In the composition of PC from white rice, flavonoids interacted with protein fractions with molecular weights of 131, 10, and 4.0 kDa; while in PC from brown rice, they interacted with only one fraction with a molecular weight of 216 kDa. The quantity of flavonoids in PC from white rice was 2.3 times less than that in PC from brown rice. Elements of protein secondary structure were established for PC: α–helix, 310 — helix, β-structure, β-bends, and irregular shape. Proteolysis of proteins was accompanied by a decrease in the number of α-helices, increase in the proportion of β-structures and irregular regions, weakening of the hydrophobic properties of proteins and an increase in the number of S–S bonds; PC from brown rice was characterized by a higher content of –СН2 groups from the flavonoid family, as well as by a higher degree of unsaturation of groups of benzene nuclei, ketone and ester groups. A negative correlation was found between the foaming ability of PC and the upper boundaries of molecular weights (r = — 0.95), quantity of high-molecular weight proteins (r = — 0.80) and aggregation constants, and a positive correlation (r = + 0.8) with the number of S–S bonds. The high foaming ability is interrelated with proteins with a molecular weight of no more than 120 kDa. The results are intended to regulate the functional properties of protein products based on the characteristics of the physicochemical properties of native and modified proteins.

Effect of egg yolk lipoproteins on foaming properties and interfacial behavior of egg white: Insights into implications for aerated food production

Chicken eggs are often used as an ingredient in oil-containing aerated foods. Different egg yolk lipids have different influence on the foaming properties of egg white, but the exact mechanism behind this influence is not well understood. In this study, we aimed to investigate how high and low-density lipoproteins present in egg yolks impact the macroscopic foam characteristics, rheological properties, and air/water (a/w) interfacial behavior in egg white foams. We found that the addition of low-density lipoprotein (LDL) at a concentration as low as 0.1 % led to a significant decrease in foaming ability (FA) by 284.67–66.67 %. Conversely, high-density lipoproteins (HDL) improved the FA from 284.67 % to 340.67 % within the concentration range of 0.024–0.16 %. Rheological properties showed that the addition of LDL caused a decrease in the viscoelasticity of the interfacial membrane, while HDL had no significant effect on viscoelasticity. Interfacial behavior results suggested that LDL and HDL were detrimental to the diffusion of protein molecules at the a/w interface. This implied that the effects of LDL and HDL on the foaming properties of EWP were mainly due to the competitive adsorption of lipids and proteins at the A/W interface, as well as the interactions between them. This work provides new insights into the effect mechanism of different forms of egg yolk lipids on the foaming properties of egg white, which can be beneficial for regulating oil-containing aerated foods to meet production demands.

Shampoo made with goat milk yogurt: Physicochemical characteristics, dirt dispersion and conditioning performance

Goat milk yogurt (GMY) compounds can benefit the skin by moisturizing, regenerating the epidermis, and improving its immunological status, making it appealing to the cosmetic industry. This study compared the physicochemical, dirt dispersion, and conditioning characteristics of shampoos made with GMY for 60 days. Shampoos with 0%, 10%, 20%, and 30% GMY were made, and pH, foam ability and stability, surface tension, viscosity, wetting time, dirt dispersion capacity, color and conditioning performance were measured at 0, 30 and 60 days after container opening. Repeated Measures ANOVA procedure was carried out to evaluate the GMY concentration in the shampoo and time. pH and surface tension of shampoo decreased as GMY percentage was increased in the formula. These shampoos had good foaming ability, cleaning and hydration capacity, and conditioning performance, even more than goat milk shampoo. The GMY shampoos were more luminous and displayed a different color compared to control shampoo. However, they were less viscous, especially when 30% of GMY was added. During the 60 days after opening, the shampoo with 10–20% of GMY had the best features. Nevertheless, for better acceptance and spreadability of the shampoo in the hair, it is necessary to correct its viscosity.

Enhancement of the rheological properties of magnetorheological foam via different constraint volumes foaming approach

The potential of magnetorheological (MR) foam, a recently developed porous smart material, has grown rapidly in recent years. The ability of MR foam to change its properties continuously, actively, and reversibly in response to a controlled external magnetic stimulus is one of its advantages for applications in advanced technology industries. However, its ability to store energy is still relatively low. This study attempts to address this drawback by highlighting a method to improve this ability by enhancing the material's storage modulus by introducing constrained foaming during the fabrication process. MR foam containing 75 wt% carbonyl iron particles (CIPs) was prepared in situ using two foaming approaches: free and constrained foaming. The effect of constraint foaming on the storage modulus enhancement was further investigated by reducing the mold length by 25 % and 50 %. The rheological properties of the fabricated MR foam samples were then examined using a rheometer in both the absence and presence of magnetic fields in an oscillatory shear mode. Thus, this study showed that constraint foaming has successfully improved the properties, especially regarding storage modulus and MR effect. When the mold volume was further reduced by 50 %, the storage modulus increased by about 50 % compared to a free-foaming MR foam at off-state conditions. Meanwhile, the results portrayed a higher storage modulus value under a 0.659 T magnetic field. This positive enhancement was believed to be due to a more compact CIP distribution. Hence, constraint volume MR foams were able to form stronger chain-like structures. The micrograph analysis by digital microscope revealed that the pore size decreased as the mold length was reduced. A shorter mold resulted in a more compact distribution of magnetic particles. As a result, MR foam with constrained foaming, especially at 50 % mold length, has a higher storage modulus. Overall, using constrained foaming to fabricate MR foam could improve the structure and mechanical properties of MR foam for a wide range of smart devices.

Impact of soy protein dispersibility on the structural and sensory properties of fat-free ice cream

Soy protein can be an effective fat replacer in ice cream due to its contribution to the viscosity and foaming ability. In this study, we investigated the individual effect of soy protein particle size and mix viscosity on the physical, rheological, tribological and sensory properties of fat-free ice cream. Particle size was varied by homogenization and subsequent separation of the dispersible and non-dispersible fractions. Three series of ice cream mixes were made in which (i) particle size and viscosity were varied, (ii) particle size was varied with a constant viscosity, and (iii) the ratio between the dispersible and non-dispersible protein fractions, particle size and viscosity were varied. The results showed that dispersible protein particles (0.25 μm) led to lower hardness and higher scoopability as their presence was related to increased overrun and reduced non-air thickness between the air cells. In comparison, large non-dispersible particles (3.8–145 μm) enhanced the melting resistance and stability of ice cream by forming a network in the serum phase. Therefore, the size of the protein particles determined their functionality in ice cream. Based on sensory evaluation, samples with a protein particle size of approximately 4 μm showed a relatively denser texture, a lower melting rate and better lubrication behavior (lower friction), as well as a sensory profile similar to that of full-fat ice cream. This study indicates that both textural and sensory properties of fat-free ice cream can be improved by manipulating the size of plant proteins and mix viscosity.

Closed-cell aluminum foams with spherically-adjustable pores: Numerical and experimental investigation of effective parameters

The study investigates the effects of pore diameter, pore spacing, and arrangement on the energy absorption ability of closed-cell aluminum foam. The optimal arrangement of pores for energy absorption was determined using experimental design and the finite element method. Aluminum 6063 with a simple cubic structure was found to be the most efficient at energy absorption, while aluminum 356 with a simple cubic structure was the least effective. As the load rate increased, the effect of the parameter t exceeded that of h in both structures. The response surface method’s proposed model was deemed effective, with the difference between experimental and predicted values around 15%–20%.

Synthesis and surface properties of branched-chain tertiary fatty alcohol sulfate surfactants

Abstract In this paper, anionic branched-chain tertiary fatty alcohol sulfate surfactants were synthesized from n-hexene and n-octene using selective olefin dimerization, hydration reaction (hydroxylation), and sulfur trioxide sulfation. The direct hydration reaction of the α-olefin dimer 2-butyl-1-octene with water as a model reaction was explored for the synthesis of branched-chain tertiary fatty alcohols. Two branched-chain tertiary fatty alcohol sulfate surfactants, namely C12-SBTAS and C16-SBTAS, with different carbon chain lengths, were synthesized by the sulfur trioxide sulfation method. Their structures were confirmed by various analytical techniques, including HPLC, FT-IR, HR-MS, and 1H NMR. Equilibrium and dynamic surface tension, foaming, wetting, and emulsifying properties were compared with those of Guerbet cetyl alcohol sulfate (C16-SGAS). C12-SBTAS and C16-SBTAS exhibited good surface activity with equilibrium surface tension (γ CMC) values of 27.41 mN m−1 and 26.69 mN m−1, respectively. They also had low foaming and rapid defoaming abilities, as well as good wetting and emulsifying properties, which match the application characteristics of typical branched-chain surfactants.

Valorisation of prawn/shrimp shell waste through the production of biologically active components for functional food purposes.

The aim of the work was to develop a technology for using waste from prawn and shrimp processing as a source of active ingredients that could be used in the promotion of healthy foods. From fresh and freeze-dried prawn and shrimp shells, protein hydrolysates (carotenoproteins) were obtained using two different enzymes, Flavourzyme and Protamex. The obtained hydrolysates were characterised in terms of protein content, degree of hydrolysis, and antioxidant and antimicrobial activity. The hydrolysate with the best antioxidant properties (FRAP value of 2933.33 μmol L-1 TE; ORAC value of 115.58 μmol L-1 TE) was selected and tested for its possible use as a component of functional foods. Molecular weight distribution, amino acid profile and free amino acids, the solubility of the hydrolysate in different pH ranges as well as foaming ability were determined. It was found that this hydrolysate was characterised by an amino acid profile with high nutritional value, flavour enhancement properties and excellent solubility in a wide pH range (from 97.06% to 100%). Afterward, the possibility of using carotenoproteins from prawn waste as a component of an emulsion with furcellaran and a lipid preparation of astaxanthin, taken from post-hydrolysate production waste, was investigated. The obtained complexes were stable as proved by the measurement of zeta potential (ζ = -23.87 and -22.32 to -27.79 mV). It is possible to produce stable complexes of the hydrolysate with furcellaran and to emulsify a lipid preparation of astaxanthin, obtained from waste following production of the hydrolysate, in them. © 2023 Society of Chemical Industry.

Enhancement of foaming properties and storage stability of pasteurized liquid egg white through ultrasound modification

Due to the high heat sensitivity of liquid egg white (LEW), there were a loss of foaming properties during pasteurization. At the same time, the temperature of pasteurization was limited by this property and did not limit the growth of microorganisms very well. Therefore, the article hoped to improve the foaming characteristics of pasteurized liquid egg white (PLEW) and to increase the stability during storage by using water-bath ultrasound. It was found that the foaming capacity of the pasteurization only group increased from 270% to 326% under optimal sonication conditions (60 Hz, 400 W, 15 min). The increase in protein solubility and decrease in particle size following ultrasound suggested that ultrasound had a deaggregation effect. The fact that surface tension was reduced suggested that sonication could provide more soluble proteins and a more flexible conformation for PLEW. Both free sulfhydryl and surface hydrophobicity were enhanced, which might be related to the disruption of protein molecular forces by the cavitation effect of ultrasound. The results of spectral analysis again revealed that the essence of ultrasound to improve the foaming properties of PLEW lied in changing the conformation of the protein molecule. Furthermore, the results also demonstrated that the ultrasound-treated LEW showed better foaming properties, minimal changes in viscosity, lower total volatile basic nitrogen content, and a longer shelf life (40 d) during storage. The quality of the ultrasound-treated group remained the most stable. Therefore, ultrasound has great potential for improving the foaming ability and stability of PLEW.

Evaluation of the Performances of Foam System as an Agent of Enhancing Oil Recovery

Foam has been used in petroleum engineering to enhance oil recovery for many years. It is a very complicated dispersion system, and the performances are affected by many factors. In order to understand the influence rules and mechanisms of such factors, the performances and mechanisms of foam systems are investigated by static and core flooding experiments with Sodium Dodecyl Sulfate. It is found that a polymer may reduce the foaming ability, but significantly enhance the foam stability in both oil-free and oil-bearing environments, while the optimal concentration is around 1500 mg/L in this case. NaCl may reduce the stability, but the capability of enhancing the foaming ability and oil tolerance gradually increases and stabilizes when the concentration reaches to 7000 mg/L. Oil can reduce the foam stability, and the stability decreases as the oil saturation increases to 0.15. Moreover, the foam stability is worse in light oil conditions than in heavy oil conditions. In the sand-pack tests, the resistance factors of foam are much higher than that of a polymer solution. The maximum resistance factor of the foam tested reaches about 230. The residual resistance factor of polymer-enhanced foam (PEF) is generally larger than that of pure foam and salt enhanced foam (SEF) in an oil-free environment. The maximum value of resistance factor of PEF and SEF is only about 60, and that of pure foam is less than 40 in an oil-bearing environment. In the parallel sand-pack tests, both ultimate oil recovery and incremental oil recovery are the best when using PEF, with SEF the second, and pure foam the worst.

Excellent condensate and salt‐resistant foam by anionic‐zwitterionic‐cationic Gemini surfactants compounds for gas well deliquification

AbstractThe blockage caused by liquid loading poses a major problem to the aged gas wells. Various categories of foaming surfactants including zwitterionic, anionic and cationic surfactants are often used for foam‐based gas well deliquification. In this study, a foaming formula containing anionic (sodium lauroyl sarcosinate, LSS), cationic Gemini (C16AGB and C12AGB) and zwitterionic (C16APB and C12APB) surfactants was developed. This foaming formula was first optimized through the foaming ability and foam stability tests, and then evaluated through liquid unloading performance tests under various salinity, condensate, methanol and temperature conditions. Synergy was observed in the foaming ability and foam stability measurements when LSS, C16AGB, C12AGB, C16APB and C12APB were combined at a molar ratio of 5:4:1:4:1. The foaming formula exhibited excellent liquid unloading performance at high salinity (up to 26 × 104 mg/L), high condensate fraction (up to 25%) and high methanol fraction (up to 50%) conditions. The presence of 10% methanol significantly enhanced foaming efficiency (referred to as the ratio of the foam mass to the initial liquid mass) and liquid unloading efficiency of the foaming formula at 20–90°C. Furthermore, the surface tension measurements and the foam morphological investigation were carried out to reveal the observed synergy.