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[en] Full text: A technology of utilaztion of waste of various kinds of plastics by means of their joint hydrocracking with black oil in the presence of suspended catalyst has been worked out. A yield of light products makes up 90 percent against 70 percent without addition of polymers per one pass
[en] A solution for energy saving by heating the NPP's River Bench Pump Station using the waste heat from recirculating pumps is developed by the Energoproekt plc. The issue is assessed both from technical and economical point of view
[en] The document includes 6 papers presented at the 6. Seminar of the IIE-ININ-IMP (Mexico) on technological specialties in the field of energy savings. (Topic 7). One item was in INIS subject scope and a separate abstract was prepared for it
[en] One of the methods for improving of the energy efficiency is the use of a secondary energy resources such as waste products from industrial processes. In case of the oil extraction a great amount of waste product (sunflower shells) with a good thermal potential is available. During the industrial process from 100 kg raw material 15 kg shells are obtained. The combustion heat is about 1700 kJ/kg. The volatile compounds yield is 66.1%. An installation has been constructed intended to use the waste product from the extraction, consisting of: a water tube boiler with a steam capacity of 20 t/h and two PKM-12 type flue boilers and two DKVR 10-13 type water tube boilers. The DKVR 10-13 type boilers are designed for the production of 22.77 kg/s saturated steam with pressure 1.28 MPa and temperature 194oC. They have an unified constructional schemes with a two-drum evaporating system and a natural circulation. The furnace has a horizontally evaporation beam washed by the gas flux. The reconstruction is aimed to create condition for the use of the sunflower shells as a main fuel and the natural gas or other fuel as additional. The scheme is one using the sloping bed combustion. 70% of the steam production is due to the shells combustion. Calculations for the grid parameters have been done. An additional heater improves the efficiency with 4.5% and the expected annual fuel saving is 300 t. The introduction of hot air (165oC) provides both combustion and ecological benefits
[en] Past numerical simulations and experiments of turbulence exhibit a hump in the inertial range, called the bottleneck effect. In this paper, we show that sufficiently large inertial range (four decades) is required for an effective energy cascade. We propose that the bottleneck effect is due to the insufficient inertial range available in the reported simulations and experiments. To facilitate the turbulent energy transfer, the spectrum near Kolmogorov's dissipation wavenumber has a hump
[en] Recovering the wasted heat from thermal plants, either nuclear or not, is a matter of energy efficiency and should be seen as such. While there are several experiences of nuclear heat production worldwide, none is located in France. This paper examines how innovation intermediaries could interact with other important actors identified by the multi-level perspective (MLP) framework, the niche actors and regime actors, to create niches for nuclear heat production in France. Employing the MLP in practice consists in exploring strategies and pathways for how change and persistence can occur in the same system. Intermediary actions have been gaining importance as coordination agents facilitating the emergence of innovative energy systems, and this especially in liberalized countries. Well understanding their role is crucial as it may help moving beyond technology-push approaches, which often lead to tension, low legitimacy and credibility. Those intermediaries that aim to stimulate niche creation for nuclear heat production project could provide permanent domains for the exchange of ideas and draw upon these exchanges to build-up trustworthy business relationships among a wide variety of actors. Sharing questions instead of knowledge is important at preliminary stages. The stimulation of windows of opportunity is also necessary to change the status quo. In addition to financial support, national authorities need to provide a clear long-term strategy of where the future energy system is going
[en] Since the implementation of the EEG in Germany the biogas production becomes an independent branch of industry in the agriculture. At this time more than 90 percent of the biogas plants work with co-generation plant for heat and power with a thermal engine efficiencies of more than 50 percent. Because of the location in the rural area heat costumers with a continuous demand of heat over the whole year are rare. This research had a closer look how to use the heat of biogas production efficiently and also generating profit. The aim of the study was to use heat over the whole year, a profitable heat concept without counting the KWK-bonus and an added value on the farm. During the study the following concepts were analyzed: asparagus production using soil heating, drying equipment for different products, the production of fish in aquaculture, the poultry production and the heated production of tomatoes. The results showed different concepts using heat of biogas plants as efficient for farmers. However with only one concept the aims - to use the heat over the whole year, generating a profitable heat concept without counting the KWK-bonus, add an value on the farm - mostly can not be achieved. The combination of different heat concepts is necessary. In this analysis the poultry production in combination with the dryer can be considered as the most efficient concept. Bearing in mind the benefit which can be generated with a heat concept as well as the higher income and the higher technical efficiency of biogas plants operators should implement an individual concept for their heat.
[en] A paradigm based on the absolute equilibrium of Galerkin-truncated inviscid systems to aid in understanding turbulence (T.-D. Lee, 'On some statistical properties of hydrodynamical and magnetohydrodynamical fields,' Q. Appl. Math. 10, 69 (1952)) is taken to study gyrokinetic plasma turbulence: A finite set of Fourier modes of the collisionless gyrokinetic equations are kept and the statistical equilibria are calculated; possible implications for plasma turbulence in various situations are discussed. For the case of two spatial and one velocity dimension, in the calculation with discretization also of velocity v with N grid points (where N + 1 quantities are conserved, corresponding to an energy invariant and N entropy-related invariants), the negative temperature states, corresponding to the condensation of the generalized energy into the lowest modes, are found. This indicates a generic feature of inverse energy cascade. Comparisons are made with some classical results, such as those of Charney-Hasegawa-Mima in the cold-ion limit. There is a universal shape for statistical equilibrium of gyrokinetics in three spatial and two velocity dimensions with just one conserved quantity. Possible physical relevance to turbulence, such as ITG zonal flows, and to a critical balance hypothesis are also discussed.
[en] Highlights: • The normolized velocity at the mid-center of T-junction is the largest near wall region. • The CWT-result gives wavelet spectrum information about the time-frequency characteristics of the flow in T-junction. • The DWT-result reveals the multi-resolution energy characteristics. Increasing the velocity ratio will supress the large-scale structure and enhance the energy cascade. Experimental measurements in a T-junction with one inlet and two outlets mimicking the airflow in a high-speed train ventilation system were carried out using well-resolved Hot-Wire Anemometry (HWA). Continuous wavelet transform (CWT) is used to analyze the time-frequency contents of the instantaneous streamwise velocity; and the discrete wavelet transform (DWT) is employed to determine the multi-resolution energy characteristics. The measurements and analysis are carried out at three representative streamwise locations, i.e., upstream, mid-center, and downstream of the T-junction. The results show that the normalized time-average velocity at the mid-center of the T-junction is the largest near the wall region. Comparing the CWT data in the region near the wall, it is found that the dominant frequency of the periodic high energy coherent structures increases along the streamwise direction, and the wavelet energy magnitude at mid-center of T-junction decreases with the increase of velocity ratio. The DWT results show that apparent wavelet energy peak appears at the upstream and downstream of the T-junction for different scales from 26 to 210, but not at the mid-center. However, the energy at scale 211 abruptly rises in all flow regions at all the three streamwise locations and this energy decreases with the increase of the velocity ratio. Therefore, a higher velocity ratio is preferred for suppressing the generation of large-scale coherent structures to reduce drag forces and skin frictions for high-speed trains.