Sustainable Ways and Methods of Recycling Epoxy Fiberglass Waste

This article presents two technological ways of recycling the wastes of the production and application of products made of highly oriented fiberglass bound by the epoxy matrix. The first technology is aimed at shredding the epoxy-based products obtained by pultrusion to create fine and ultrafine powders (up to 2-10 microns) used as fillers in various composites. The second technology offers a way to obtain coarse powders with a particle size of up to 100 microns, used in the composition of heat-insulating materials and fire-retardant intumescent coatings. Proposed is the mechanical grinding of fiberglass to a finely dispersed state with subsequent heating to a temperature of 400 °C in the presence of a foaming coke and liquid glass. This technology allows the full utilization of waste from the production and application of epoxy fiberglass, such as windmill blades and parts of molded products, leading to the creation of an environmentally friendly fire-resistant and heat-insulating material in the form of plates, blocks and other products with operation temperature up to 400C, as well as fire retardant coatings for building materials and structures. By varying the content of the foaming agent and soluble glass in the composition of the intumescent mixture, one can regulate the average density, thermal conductivity and strength of the material within significant limits, achieving characteristics that exceed those of traditional heat-insulating materials. The proposed material based on recycled epoxy fiberglass is inflammable and resistant to unfavorable environmental impacts; it has high biostability and provides heat and mass transfer during the operation in buildings and structures.

Optimization of the stages of a ship's cargo plan development for shippining of general cargoes

One of the main tasks in stability calculations is to provide the ship with the necessary (optimal) trim whose final value is influenced by the arrangement of cargo on the ship. Today, however, there are rules and requirements but there is no unified approach to developing a cargo plan for a vessel that simultaneously transports various types of general cargo. In order to improve the efficiency of the above calculations, a procedure has been proposed to optimize developing a cargo plan for a vessel carrying heterogeneous general cargoes at the same time, the main idea of which is to distribute consignments on the ship in two stages, taking into consideration the compensating trimming moment. The scheme to develop a cargo plan has been improved by introducing the developed procedure. The results of verification confirmed its effectiveness in practice. Possible deviations of the values for the trim required (optimal) for the voyage from the actual one calculated after the allocation of stocks and consignments of goods have been investigated using an example of the series of developed cargo plans. It should be noted that the value for the trim, required (optimal) and actual, for each individual cargo plan does not differ by more than 8 %. The results reported in this paper give grounds to assert the expediency of their application when developing cargo plans for tramp shipping vessels. The introduction of the procedure could make it possible to effectively load a vessel with the full utilization of both its carrying capacity and cargo capacity. The use of the proposed scheme for developing a cargo plan to transport heterogeneous cargoes would reduce the total time for calculating the stability and strength of the vessel in general

Thermo-Economic Comparison Between Organic Rankine Cycle and Binary-Flashing Cycle for Geothermal Energy

Geothermal energy is a characteristic of widely distributed, high capacity factor, high reliability, and lower environmental impact potential values. And it will play an important role in achieving the goal of carbon neutral carbon peak. Nonetheless, geothermal energy presents its own particular challenges, i.e., the high investment cost and long payback period. The binary flashing cycle (BFC) system is proved to be a promising power generation technology due to the efficient and full utilization of a low-grade heat source. While the economic performance still needs further evaluation, in the present study, the thermo-economic comparison between organic Rankine cycle (ORC) and the BFC for geothermal energy has been investigated. R245fa has been chosen as the working fluid. Considering the thermodynamic and economic performance simutaneously, several evaluation indicators were selected including thermal efficiency, exergy efficiency, net power output per ton geothermal water, heat exchanger area, and heat recovery efficiency, and the system modeling and comparison were presented. The simulation results reveal that the BFC system obtains 32% more net power output than the ORC system under the working conditions investigated. The heat recovery efficiency of the BFC is 1.96 times as much as that of the ORC, which indicates that the BFC can realize the full utilization of low-grade energy. And more heat exchanger areas are required in the BFC system. What is more, the preliminary discussion of the economic feasibility of BFC system applied in the FengShun geothermal power plant is presented. The payback period of the BFC is just 6.0 years under the generation pressure of 600 kPa. It is indicated that the BFC system has obvious economic benefits, especially in a nonflowing geothermal well.

Spin Wave Normalization Towards all Magnonic Circuits

The key enabling factor for Spin Wave (SW) technology utilization for building ultra low power circuits is the ability to energy efficiently cascade SW basic computation blocks. SW Majority gates, which constitute a universal gate set for this paradigm, operating on phase encoded data are not input output coherent in terms of SW amplitude, and as such, their cascading requires information representation conversion from SW to voltage and back, which is by no means energy effective. In this paper, a novel conversion free SW gate cascading scheme is proposed that achieves SW amplitude normalization by means of a directional coupler. After introducing the normalization concept, we utilize it in the implementation of three simple circuits and, to demonstrate its bigger scale potential, of a 2-bit inputs SW multiplier. The proposed structures are validated by means of the Object Oriented Micromagnetic Framework (OOMMF) and GPU-accelerated Micromagnetics (MuMax3). Furthermore, we assess the normalization induced energy overhead and demonstrate that the proposed approach consumes 20% to 33% less energy when compared with the transducers based conventional counterpart. Finally, we introduce a normalization based SW 2-bit inputs multiplier design and compare it with functionally equivalent SW transducer based and 16nm CMOS designs. Our evaluation indicate that the proposed approach provided 26% and 6.25x energy reductions when compared with the conventional approach and 16nm CMOS counterpart, respectively, which demonstrates that our proposal is energy effective and opens the road towards the full utilization of the SW paradigm potential and the development of SW only circuits.

A novel Penicillium sumatraense isolate reveals an arsenal of degrading enzymes exploitable in algal bio-refinery processes

Background Microalgae are coming to the spotlight due to their potential applications in a wide number of fields ranging from the biofuel to the pharmaceutical sector. However, several factors such as low productivity, expensive harvesting procedures and difficult metabolite extractability limit their full utilization at industrial scale. Similarly to the successful employment of enzymatic arsenals from lignocellulolytic fungi to convert lignocellulose into fermentable sugars for bioethanol production, specific algalytic formulations could be used to improve the extractability of lipids from microalgae to produce biodiesel. Currently, the research areas related to algivorous organisms, algal saprophytes and the enzymes responsible for the hydrolysis of algal cell wall are still little explored. Results Here, an algal trap method for capturing actively growing microorganisms was successfully used to isolate a filamentous fungus, that was identified by whole-genome sequencing, assembly and annotation as a novel Penicilliumsumatraense isolate. The fungus, classified as P.sumatraense AQ67100, was able to assimilate heat-killed Chlorellavulgaris cells by an enzymatic arsenal composed of proteases such as dipeptidyl- and amino-peptidases, β-1,3-glucanases and glycosidases including α- and β-glucosidases, β-glucuronidase, α-mannosidases and β-galactosidases. The treatment of C.vulgaris with the filtrate from P.sumatraense AQ67100 increased the release of chlorophylls and lipids from the algal cells by 42.6 and 48.9%, respectively. Conclusions The improved lipid extractability from C.vulgaris biomass treated with the fungal filtrate highlighted the potential of algal saprophytes in the bioprocessing of microalgae, posing the basis for the sustainable transformation of algal metabolites into biofuel-related compounds.

Spin Wave Normalization Towards all Magnonic Circuits

The key enabling factor for Spin Wave (SW) technology utilization for building ultra low power circuits is the ability to energy efficiently cascade SW basic computation blocks. SW Majority gates, which constitute a universal gate set for this paradigm, operating on phase encoded data are not input output coherent in terms of SW amplitude, and as such, their cascading requires information representation conversion from SW to voltage and back, which is by no means energy effective. In this paper, a novel conversion free SW gate cascading scheme is proposed that achieves SW amplitude normalization by means of a directional coupler. After introducing the normalization concept, we utilize it in the implementation of three simple circuits and, to demonstrate its bigger scale potential, of a 2-bit inputs SW multiplier. The proposed structures are validated by means of the Object Oriented Micromagnetic Framework (OOMMF) and GPU-accelerated Micromagnetics (MuMax3). Furthermore, we assess the normalization induced energy overhead and demonstrate that the proposed approach consumes 20% to 33% less energy when compared with the transducers based conventional counterpart. Finally, we introduce a normalization based SW 2-bit inputs multiplier design and compare it with functionally equivalent SW transducer based and 16nm CMOS designs. Our evaluation indicate that the proposed approach provided 26% and 6.25x energy reductions when compared with the conventional approach and 16nm CMOS counterpart, respectively, which demonstrates that our proposal is energy effective and opens the road towards the full utilization of the SW paradigm potential and the development of SW only circuits.

Availability Study of a Longwall Shearer Including Phases of its Operation

The mining production process includes a number of sub-processes, the most important of which is mining the rock mass. In this process, increasingly modern mining machines are being used to replace human labor and to achieve high productivity. Full utilization of the potential of these machines is of great importance for the efficiency of individual stages and the whole process of mining production. In the process of mining the rock mass, the use of machinery of a mechanized longwall system is of fundamental significance. Their availability, efficiency and reliability significantly affect the efficiency of the whole mining production process. The paper refers to the availability of a longwall shearer as the basic machine of a mechanized mining system. Based on the analysis of diagnostic signals, recorded by the industrial automation system, the availability of the longwall shearer was determined for 10 selected cycles of its operation. The analysis also included the phases of these cycles, treated as separate periods of the shearer’s work. This division is a consequence of a great difference in the character of the shearer’s work in particular phases of the operating cycle. The analysis covered the phases of cutting, mining and shunting. The determined temporal waveforms and the shearer’s availability in these phases show their great diversity. Therefore, the results indicated the necessity to analyze the operation of mining machines in their characteristic periods, which can be the basis for minimizing unplanned interruptions in their operation and improving the efficiency of their use.