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Torrefaction is considered as a method for producing biofuels with improved characteristics compared to those of the “raw” biomass (higher calorific value, moisture resistance, better grindability). The torrefaction process is an endothermic process that is usually carried out in a gaseous atmosphere in the absence of oxygen. To reduce the required heat input, it is proposed to employ the oxidative torrefaction and conduct the process in a fluidized bed agitated with flue gases containing less than 6% oxygen. Preliminary studies of the oxidative torrefaction of sunflower husks, including thermogravimetric analysis of the treated material, have shown that the heat treatment time for the biomass should be at least 5 min. A fluidized bed is a reactor with ideal mixing of the treated material where uniform treatment of raw material particles cannot generally be attained. To overcome this disadvantage of the fluidization technique and achieve the required residence time for biomass in a fluidized bed during a continuous torrefaction process, it was proposed to equip a torrefaction reactor with a series of vertical baffles spaced at 50 mm. These baffles induce a loop-like flow of the processed biomass from the inlet to the outlet of the reactor. To investigate the residence time for husk particles in the reactor, a tracer, which was colored to husk particles' color with a water-soluble dye which did not change the weight and size of the particles, was injected into the bed of uncolored particles. Tracer samples were taken every 30 s at the outlet of the reactor and were analyzed using a special procedure to determine the fraction of colored particles in each sample. This enabled us to gauge the time during which the colored particles injected into the fluidized bed reached the point of their discharge from the bed. Studies performed in a “cold” model of the reactor showed that a series of vertical baffles in the bed can provide the required residence time for biomass in a reactor including commercial reactors. Plates can provide the necessary biomass residence time in the reactor.

The article deals with the issues of engineering arrangement of the territory for the nursery and the mother plant garden of common hazel - the layout of the nursery, the choice of the irrigation method, the calculation of the reservoir volume, irrigation rates, and production efficiency.

Abstract This study presents and evaluates the feasibility of a novel hybridization of modified Kalina cycle, reverse osmosis desalination, and low-temperature water electrolysis utilizing geothermal energy to yield power, distilled water, and hydrogen, respectively. The scientific impact of the current work has been improved considering the features of Sabalan flash-binary geothermal wells in Iran as a real model through a case study. In addition to designing a novel setup, the smart use of multi-heat recovery technique, modifying the base cycle, and utilizing a part of generated distilled water to produce hydrogen by the electrolyzer are the other structural originalities, distinguishing the current work from the previous studies. The suggested system is scrutinized via a parametric study and optimized based on a genetic algorithm. The parametric study demonstrated that the highest sensitivity of varying the performance criteria of the whole system is attributed to the change in flash tank pressure. Moreover, the multi-objective optimization led to achieving the exergy efficiency and trigeneration gain output ratio as 51.3% and 1.7 for the system, respectively. Furthermore, the system was able to produce 4795 kW of power, 5.3 kg/h of hydrogen, and 19.9 kg/s of distilled water.

One of the important issues is the assessment of the strength of the elements of hydraulic structures, spillway structures, reservoirs, and hydraulic complexes, the determination of the connection mode of the basins, and the reduction of kinetic energy in the reinforced fields of the downstream pool. In this regard, it is especially important to determine the hydrodynamic characteristics of the flow of water moving in the apron and risberme area, which provides the stability of the downstream pool - the areas that indicate the distribution and direction of velocity and pressure.

Purpose: The aim of this work is the operational electrophysical method of the control for contamination and purification of soil from oil products and the identification of changes in the soil properties in electrochemical processing to determine rational modes of processing.Methods: Investigations are performed on the laboratory setup including the two -electrode scheme of electric treatment of the artificially polluted soil .The setup is equipped with a system of micro sensors of specific electrical resistance. Traditional laboratory tests are used to determine the physical and mechanical properties of soils. The possibility of control for soil purification by electrochemical method using a system of continuous operational geophysical monitoring is considered.Results: Changes in the physical properties of contaminated soils are experimentally confirmed when exposed to the electric current. A physical model is created for coagulation of oil products in pores during the electrical processing. It increases the amount of sand and clay components with changes in the electrical resistance of soil. The physical processes in the clean and polluted soil are compared. It is shown that when electric current passes through contaminated soils, oil products in pores transfer to a solid, less toxic state, which leads to a change in the specific electrical soil resistance throughout the zone processed. This pattern should be used to control soil decontamination.

The object of the study is the water supply and sanitation system of an industrial enterprise. Currently, many enterprises do not use the treated industrial waste water in the water supply cycle. Therefore, the use of treated wastewater is of practical importance. The scheme of thermal treatment of waste water for obtaining pure condensate by evaporation is proposed. The main results of the study are the technical solution for the development of the enterprise's wastewater treatment complex. Pure condensate is obtained in an instant boiling evaporator. The research method is based on the calculation of energy costs in wastewater treatment for different types of waste water. The results of the study allow us to determine the optimal set of energy equipment for obtaining pure condensate and its further use. The specific practical significance lies in the development of a technical solution that helps the treatment of wastewater and the reduction of emissions into the water basin.

Background Solving the problem of scaling on the inner surfaces of downhole and associated equipment is one of the most important tasks in oil production. Crystalline compounds formed in the stratums, as well as at all stages of oilfield equipment operation, lead to premature pumps wear and jamming, thereby leading to losses in the product of extraction and an increase in the economic costs of repair and purchase of new equipment. Aims and Objectives The aim is to choose a method to prevent salt deposition and its testing at Romashkinskoye oil field. Results Based on the data on one of the areas of the Romashkinskoye oil field, three methods for controlling salt formation have been studied: 1) prevention of salt formation by inhibitory protection (SNPCH 5314 reagent); 2) method for preventing salt and paraffin deposits based on electrophysical phenomena by implementing Weatherford's ClearWELL instrument, which is a device installed by means of a ferrite ring in production wells; 3) technology of short-time well operation, which consists in the periodic replacement of fluid pumping and its accumulation in the well. The most effective method of prevention salt formation was selected, in which the process of exploitation did not reduce depression to the stratum, consequently, the volumes of oil production at the Romashkinskoye oil field were not lost, and the number of repairs related to the salt formation problem decreased.

Pharmaceutical and personal care products (PPCPs) are discharged into receiving water bodies mainly from sewage treatment plants. Due to the inefficient removal in conventional wastewater treatment facilities, PPCPs have become a major concern to aquatic ecosystems, water quality, and public health worldwide since they cause harmful effects on aquatic life and human even at low doses. Among the PPCPs, carbamazepine (CBZ) is one of the most commonly prescribed anticonvulsant drugs and consumed more than 1,000 tons per year. Due to its structural complexity, CBZ is known as recalcitrant compound highly stable during wastewater treatment. Consequently, it has become one of the most frequently detected pharmaceuticals in waste water, surface water, and even drinking water. In this study, Korean indigenous microalgae strains were tested as eco-friendly and cost-effective solutions for CBZ removal. Based on the preliminary biological CBZ degradation tests, Tetradesmus obliquus KNUA061 demonstrating the best CBZ removal rate was selected for further experiments. In order to increase strain KNUA061's CBZ removal efficiency, NaOCl, which is widely accepted in the water purification process, was used as an additional stimulus to induce stress conditions. At around 20 μg L−1 CBZ, addition of 1.0 mg NaOCl resulted in approximately 20% of removal rate increase without suppressing cells growth. Roughly 90% of CBZ remained its original form and the composition of the transformed secondary metabolites was less than 10% during the biodegradation process by the microalga. Based on the results of the antioxidant enzyme activities, degree of lipid oxidation, and amino acid contents, it was concluded that the redox-defence system in microalgal cells may have been activated by the NaOCl treatment. Biomass analysis results showed that higher heating value (HHV) of strain KNUA061 biomass was higher than those of lignocellulosic energy crops suggesting that it could be utilized as a possible renewable energy source. Even though its biodiesel properties were slightly below the international standards due to the high PUFA contents, the biodiesel produced from T. obliquus KNUA061 could be used as a blending resource for transportation fuels. It was also determined that the microalgal biomass has acceptable feasibility as a sustainable dietary supplement feedstock due to its high essential amino acid contents.

AbstractAgeratum conyzoides, an herb found throughout the year, is generally considered as a weed: it causes reduction in soil productivity and leads to health hazards for cattle and humans. However, its biomass can easily represent a cost‐effective source, which can be used for lignocellulosic biofuel production. The conversion of lignocellulosic biomass to ethanol has drawn much attention in recent times due to abundance of biomass. In the present study, the cellulose and hemicellulose biomass of the leaf and stem of A. conyzoides was converted to sugars using acid hydrolysis.146.01 ± 02 mg/g of fermentable sugar was obtained from A. conyzoides. The maximum ethanol concentration 11.89 g/L was obtained after 7 days. Scanning electron microscopy was used to characterize the surface morphology after acid hydrolysis of biomass. In the current study, the residues of acid hydrolysis and fermented wastewater was used for biogas production through anaerobic digestion. The yield of biogas from the residues of acid hydrolysis and fermented wastewater was 204 L kg−1VS. The results obtained indicate that A. conyzoides may be considered as a promising feedstock for bioethanol and biogas production.