Search Results (4)

The industrial selection process of bean (Phaseolus vulgaris L.) produced in Northwest Argentina (NOA) region produces 7000 tons/year of by-products integrated from broken, bruised, and reduced-sized seeds. This investigation aimed to study the possibilities of using these by-products as a source of protein and starch. Samples were crushed to obtain flour (BF) with particle size of 250 µm. Starch and protein were extracted in a 6:1 and 10:1 water/flour ratio at pH 9 and 10, respectively. After centrifugation, the protein was precipitated from the supernatant at pH 4.5, and a bean protein concentrate (BPC) was obtained. The chemical composition of BF, S, and BPC was determined. Starch swelling power (SP), water solubility index (WSI), water absorption index (WAI), and syneresis in cooling (SC) and freezing (SF) conditions were determined. The proportion of molecular structure of BPC was determined using deconvolution of infrared spectrum (Amide I zone), and their solubility using Bradford reactive. The yield of obtaining processes of BPC and bean starch (BS) of high purities was 13.0 and 50.3 g/100 g of BF, respectively. The BS showed SP, WSI, and WAI values of 3.5 ± 0.5 (sediment weight g/100 g BS), 1.7 ± 1.6 (weight of the soluble BS g/100 g of BS), and 3.6 ± 0.5 (sediment weight g/weight of BS (dry solid) g), respectively. The SC was higher than SF and was double with respect to starches of other origins. The BPC solubility was 15.5 g protein/100 g BPC (pH 4.5), higher than concentrates of conventional vegetable proteins. The infrared profile showed higher proportions of deployed structures, i.e., β-sheets (22%) and random coils (18.8%), suitable for emulsifying and gelling properties. Results showed bean by-products as an alternative source of ingredients for the food industry. Full article

This article is devoted to the construction and statistical analysis of models that express the relationship between performance indicators and a large number of geological and technological factors. The volume of additionally produced oil, the volume of limited water, the duration of the effect and profit per well, taking into account the cost of the polymer, are taken as performance indicators. The key goal of the article is to develop a method and models for making technological choices to enhance the effectiveness of measures to limit water inflows in production wells under conditions of uncertainty. The methodological basis of the study was the provisions and principles of mathematical statistics, the theory of fuzzy sets, the theory of decision-making under conditions of uncertainty based on materials generated by statistical processing of data on physical and geological conditions, and the results of waterproofing work, obtaining, and analyzing information. The scientific novelty of the study lies in the construction of technological solutions based on modeling the performance indicators of waterproofing works with an assessment of the significance of each factor and the reliability of the models and decision-making under conditions of uncertainty, expressed by multi-criteria and multi-factoriality. The practical significance follows from a solution that satisfies the conditions for achieving the maximum of all indicators of the efficiency of the process of limiting water inflows, both technological and economic. An algorithm was developed and implemented for evaluating optimal technological solutions according to four criteria based on information about the geological and physical conditions of the field and the experience of implementing geological and technical measures to limit water inflows, including the analysis of factors, their weighted contribution, model building, statistical evaluation of reliability indicators, decision-making taking into account uncertainty. Full article

In view of the poor knowledge of the applicability of sediment-gelling compositions (SGCs) in waterproofing the bottom-hole zone of wells, work in this area of research is one of the most promising in waterproofing today. The key goal of this work is to study the prospect of using SGCs for waterproofing as well as to calculate the rheological characteristics of the proposed SGCs depending on variations in the components of their composition (alkali and polymer). In the course of our studies, it was found that the key factors influencing the rheological characteristics of SGCs are not only the variation in the ratio in the composition of alkali and polymer but also the degree of salinity of the formation water, which must be taken into account when developing waterproofing. During this research, it was found that due to the absence of calcium and magnesium ions in fresh water, the proposed polymers have good solubility (the exponent in the rheological model is equal to or close to unity), which leads to an increase in the viscosity of solutions. The dependence of changes in the rheological constants of SGCs on such parameters as temperature and alkali concentration have been established. It was determined that an increase in the solution temperature leads to an increase in the rheological constant n from 0.8 to 0.92 (at a polymer concentration of 0.05 and a NaOH concentration of 0.1), while a variation in the NaOH alkali concentration from 0.1 to 0.75 leads to similar changes in one measured temperature range. The results obtained can be used in the future to evaluate the use of SGCs to create barrier waterproofing in the bottom-hole zone of wells during oil production. Full article

The treatment of silted sediment in the river is a global problem. The accumulation of waste sediment will lead to an adverse impact on the environment. In this paper, the silted sediment was reused to produce geopolymer composite materials via alkali-activated gelling modification. The effects of the modifiers of sodium silicate solution, quicklime, and Na₂SO₄ admixture, and the dosage of the slag, fly ash, and silica fume admixture, and curing conditions and age, on the compressive strength and microstructure of the geopolymer-modified sediment materials were studied. The crystalline phase and hydration products of the modified sediment geopolymer composites were analyzed by X-ray diffraction (XRD) and scanning electron microscopy (SEM) with energy dispersive spectroscopy (EDS), respectively. A compressive strength test was conducted to evaluate the mechanical properties of the composites. The results showed that the type and dosage of modifier, amount of mineral admixture additive, cure conditions, and cure age had significant effects on the mechanical properties of the composites. The effect of the addition of mineral admixture on the compressive strength of the modified sediment specimens was more noticeable than that of the modifier. The compressive strength of the geopolymer-modified specimens was greatly increased by the addition of mineral dopants. When 10 wt.% silica fume is added, the compressive strength reaches a maximum value of 33.25 MPa at 60 days. The SEM-EDS results show that the C-S-H gels and C-A-S-H gels were the main hydration products. The results indicate that river siltation sediment is an excellent raw material for geopolymer-modified materials. It is feasible to produce reliable and sustainable hydraulic engineering materials by using river sediment geopolymer-modified materials. Full article