Shelf-cultivation of Strawberry with Mulch and Heat Preservation Technology with Natural Energy

It is proved that the treatment with white mulch and black thin films per- formed the best in terms of heat preservation in cultivation of strawberry with shelves. In winter, drip irrigation performed significantly in transporting hot water through solar energy. The combination of the two methods resolved the issue of heat preservation difficulty and guaranteed growth of strawberry in winter.

A Survey on a Heat Exchangers Network to Decrease Energy Consumption by Using Pinch Technology

There are several ways to increase the efficiency of energy consumption and to decrease energy consumption. In this paper. the application of pinch technology in analysis of the heat exchangers network （HEN） in order to reduce the energy consumption in a thermal system is studied. Therefore, in this grass root design, the optimum value of △Tmin, is obtained about 10℃and area efficiency （a） is 0.95. The author also depicted the grid diagram and driving force plot for additional analysis. In order to increase the amount of energy saving, heat transfer from above to below the pinch point in the diagnosis stage is verified for all options including re-sequencing, re-piping, add heat exchanger and splitting of the flows. Results show that this network has a low potential of retrofit to decrease the energy consumption, which pinch principles are planned to optimize energy consumption of the unit. Regarding the results of pinch analysis, it is suggested that in order to reduce the energy consumption, no alternative changes in the heat exchangers network of the unit is required. The acquired results show that the constancy of network is completely confirmed by the high area efficiency infirmity of the heat exchanger to pass the pinch point and from of deriving force plot.

Application of the waste heat recovery system and energy-saving in the strip continuous annealing furnace

The common problem of cold strip continuous annealing furnaces is high exhaust gas temperature and great energy consumption. Taking the cold-strip continuous annealing furnaces of Baosteel No. 4 cold mill plant as an example, several waste heat recovery systems in the annealing furnaces are compared and their advantages and disadvantages are analyzed through different energy-saving technologies.

Self-assembled aerogel sheet electrodes of thermocells for low-grade heat harvest

Efficiently harvesting low-grade heat is crucial for sustainable energy management. Thermocells(TECs), inducing heat-toelectricity conversion via the thermogalvanic effect, have thus drawn tremendous attention in recent years. This study introduces a self-assembly approach for fabricating aerogel sheet electrodes(ASEs) tailored for TECs. The crafted ASEs retain a remarkable porous architecture with approximately 95% porosity, even with their slimmed-down thickness. Results reveal that the electrode composition has minimal influence on the thermopower of TECs. Notably, the porous ASE with tunned composition demonstrates an optimal effective surface area for the thermogalvanic effect, resulting in enhanced output current density. This balances the desirable traits of electrode compactness with abundant redox active sites, positioning it favorably against conventional bulky electrode designs. The TECs utilizing the optimized ASE achieve a peak output power of 22.10 μW cm^(-2)under a temperature difference of 30 K. Furthermore, a tubular TEC device is readily assembled and specially designed for harvesting heat energy from hot fluids. These findings underscore the potential of composite electrodes in the realm of low-grade heat harvest, paving the way for broader applications in sustainable energy solutions.

Improved Efficiency of Heat Exchange Using KELEA Activated Water

An environmental force termed KELEA (kinetic energy limiting electrostatic attraction) is postulated to reduce the strength of intermolecular (hydrogen) bonding of water molecules, resulting in increased kinetic activity of the water. While regular water does not directly absorb KELEA from the environment, various dipolar compounds with separated electrical charges can seemingly act as a primary antenna for KELEA, with secondary transfer of energy into nearby water. Moreover, once sufficiently activated, the separated electrical charges in activated water can apparently function as a receiver for KELEA, leading to further activation of the water and also to the activation of added water. Prior publications have addressed the agricultural and potential clinical benefits of using KELEA activated water. This article is intended as the first in a series of papers describing useful industrial applications of KELEA activated water. The focus of the present paper is on the improved efficiency of industrial water heating and cooling systems by using KELEA activated water provided by pelleted, ground and heated volcanic rock as supplied by Kiko Technology.

Thermal analysis of an innovative flat heat pipe radiator

An innovative flat heat pipe radiator was put forward, and it has the features of high efficiency of heat dissipation, compact construction, low thermal resistance, light weight, low cost, and anti-dust-deposition. The thermal analysis of the flat heat pipe radiator for cooling high-power light emitting diode （LED） array was conducted. The thermal characteristics of the flat heat pipe radiator under the different heat loads and incline angles were investigated experimentally in natural convection. An electro-thermal conversion method was used to measure the junction temperature of the LED chips. It is found that the integral temperature distribution of the flat heat pipe radiator is reasonable and uniform. The total thermal resistance of the flat heat pipe radiator varies in the range of 0.38-0.45 K/W. The junction temperatures of LED chips with the flat heat pipe radiator and with the aluminum board at the same forward current of 0.35 A are 52.5 and 75.2 ℃, respectively.

Feasibility Demonstrations of Liquid Turbine Power Generator Driven by Low Temperature Heats

Lower temperature waste heats less than 373 K have strong potentials to supply additional energies because of their enormous quantities and ubiquity. Accordingly, reinforcement of power generations harvesting low temperature heats is one of the urgent tasks for the current generation in order to accomplish energy sustainability in the coming decades. In this study, a liquid turbine power generator driven by lower temperature heats below 373 K was proposed in the aim of expanding selectable options for harvesting low temperature waste heats less than 373 K. The proposing system was so simply that it was mainly composed of a liquid turbine, a liquid container with a biphasic medium of water and an underlying water-insoluble low-boiling-point medium in a liquid phase, a heating section for vaporization of the liquid and a cooling section for entropy discharge outside the system. Assumed power generating steps via the proposing liquid turbine power generator were as follows: step 1: the underlying low-boiling-point medium in a liquid phase was vaporized, step 2: the surfacing vapor bubbles of low-boiling-point medium accompanied the biphasic medium in their wakes, step 3: such high momentum flux by step 2 rotated the liquid turbine (i.e. power generation), step 4: the surfacing low-boiling-point medium vapor was gradually condensed into droplets, step 5: the low-boiling-point medium droplets were submerged to the underlying medium in a liquid phase. Experiments with a prototype liquid turbine power generator proved power generations in accordance with the assumed steps at a little higher than ordinary temperature. Increasing output voltage could be obtained with an increase in the cooling temperature among tested ranging from 294 to 296 K in contrast to normal thermal engines. Further improvements of the direct current voltage from the proposing liquid turbine power generator can be expected by means of far more vigorous multiphase flow induced by adding solid powders and theoretical optimizations of heat and mass transfers.

Energy Saving in Construction by Wide Application of High-Quality Insulation Based on Basalt Fibers

The influence of modern heat insulation materials on the ecological compatibility and fire resistance of residential and public buildings is considered. The nomenclature of fibrous heat insulation materials from basic rocks of volcanic origin is described. For basalt super thin fibers (BSTF), the production technology is described. The factors negatively influencing the engineering-and-economical performance of the duplex technology of production of the BSTF are analyzed. The engineering-and-economical performance of innovative enterprises for the production of basalt heat insulation and measures for its use in construction are given.

Biomass Combined Heat and Power Generation for Anticosti Island: A Case Study

Combined heat and power (CHP) plants (co-generation plants) using biomass as fuel, can be an interesting alternative to the predominant electrical heating in Canada. The biomass-fueled boiler provides heat for the steam cycle which in turn generates electricity from the generator connected to the steam turbine. In addition, heat from the process is supplied to a district heating system. The heat can be extracted from the system in a number of ways, by using a back-pressure steam turbine, an extraction steam turbine or by extracting heat directly from the boiler. The objective of the paper is the design, modeling and simulation of such CHP plant. The plant should be sized for providing electric-ity and heat for the Anticosti Island community in Quebec.

Flow and Heat Transfer of Basalt Melt in the Feeder of the Smelter Furnace

The flow and heat transfer of the basalt melt in the boundary layer on a flat plate is considered. The conditions of formation of the layer and the intensity of heat transfer are determined. A self-similar analysis using the symmetry method was used. A system of ordinary differential equations in self-similar form is obtained. The fluid flow and heat transfer of molten basalt at a laminar steady-state flow in the feeder furnaces are numerically researched. The term “protective layer” on the interface “basalt melt-lining” is introduced. The dependences for the calculation of dimensionless shear stresses and the Nusselt number on the lining surface are obtained. The conditions of rational organization of the technological process of basalt melt feeding in the furnace feeder are formulated.

Integrated Renewable Energy Solutions for Aquaculture Processing Enerfish

The European Union Framework Programme 71 Enerfish project aims to demonstrate a new poly-generation application with renewable energy sources for the fishery industry in Vietnam. The fish processing plant under consideration can be made by energy self-sufficient when all fish waste oil is processed into biodiesel and further converted to electricity and heat （for cooling） in a CHP （combined heat and power） unit. The purpose of the present paper is to discuss the profitability of such plants in southeast Asia. The economic model shows that electricity production is, due to the low electricity tariff, uneconomical （except during electricity blackout）, even if cogeneration heat can be utilized. This prompt a design of the plant whereby the necessary heat for the biodiesel process is taken from the waste heat produced by the compressors of a CO2 cooling system. According to the calculations and assumptions of the present study, the profitability of biodiesel production from fish cleaning wastes in Vietnam depends strongly on the market prices for fish waste and fish oil. Different business case scenarios are described.

COMBINING BUILDING RENOVATION AND GROUND SOURCE HEAT PUMP INSTALLATIONS FOR THE REDUCTION OF GREENHOUSE GAS EMISSIONS:A Case Study in Vaasa Finland

Given the growing interest in ground source heat pump and distributed heating installations in general for the reduction of greenhouse gas emissions,technology implementation planning can benefit from the simultaneous consideration of building renovations.Here,a method for identifying and evaluating scenarios based on cost and greenhouse gas emissions is presented.The method is demonstrated for a case study in Vaasa Finland.The case study considers the insulation of the walls,roof,and base floor and the replacement of windows based on 2003 and 2010 Finnish building codes simultaneously with the possible replacement of existing heat sources with ground source heat pumps.Estimates of changes in heat demand for consecutive renovations are combined with data on renovation,installation,heating costs,and life cycle greenhouse gas emissions data for the current and proposed heat sources.Preferred scenarios are identifi ed and evaluated by building type,construction decade,and current heating source.The results are then placed within the contexts of the Vaasa building stock and policy theory.

基于联邦学习的分布式电采暖互动模式设计与展望

随着“双碳”目标的提出,以及“以电代煤”政策的贯彻落实,大量电采暖设备取代传统燃煤取暖投入运行并接入电网将成为必然趋势。大量电采暖设备可以作为需求侧可调资源进行新能源消纳,但是分布式电采暖所处地理区域较为分散,传统集中式管理的方式又存在隐私泄露、数据孤岛等问题。联邦学习作为一种分布式技术可在保护隐私的前提下支撑电采暖负荷互动,在分布式电采暖互动领域具有较强的适用性。分析了基于联邦学习的分布式电采暖互动需求,以及边缘缓存、隐私防护、通信传输优化和异构资源融合等技术在基于联邦学习的电采暖互动场景中的应用方式,并展望了未来基于联邦学习的分布式电采暖互动前景。

炼化企业低温热系统优化技术及应用

石油炼化企业低温热系统有着巨大的节能潜力,但并没有得到企业足够的重视。针对企业低温热系统存在建设、管理分散,运行经济性低等实际问题,为了满足企业降低成本、节能减耗的目的,深入剖析了现今炼化企业低温热系统优化的关键问题,提出了炼化企业低温热系统的优化技术,建立了低温热系统的全流程优化模型,开展了低温热系统的操作优化与改造优化。应用结果表明,该技术节能降碳效果显著,而且大大提升了企业低温热系统的数字化水平。

新型储能技术进展与挑战Ⅱ:物理储能与储热技术

新型储能技术日益成为中国建设新型能源体系和新型电力系统的关键技术,已成为中国经济发展的新动能,将在促进可再生能源消纳、实现能源体系转型、提高能源利用效率、减少环境污染等方面发挥重要作用,相关技术研究也在快速发展。开展了该领域的系列评价性综述工作,分为电化学储能技术、物理储能与储热技术、储能集成与规划3个部分,对各类新型储能技术的应用领域、最新研究进展及局限性等问题进行了全面系统的对比分析,并进一步探讨了储能集成、安全、规划调度等储能系统相关领域面临的挑战及发展趋势。第2部分为物理储能与储热技术,重点对物理储能与储热技术中的压缩空气储能、飞轮储能、重力储能、相变储热、热化学储热和卡诺电池技术与工程的相关成果进行了综合分析与讨论。总体而言,物理储能和储热技术大多具有使用寿命长、安全性高的特点,且在能量转化过程中自身多具有转动惯量,属于电网支撑型的储能技术,可满足从大规模长时储能到高功率快速响应的不同需求。在新兴的物理储能和储热技术中,重力储能和卡诺电池的相关技术显示出良好的发展前景。

自动化技术在热处理领域应用研究

随着全球能源危机的加剧和环保要求的提高,制造业特别是热处理行业面临节能减排的压力。自动化技术的引入不仅改革了传统热处理工艺,而且明显提高了能效和安全性。通过优化工艺流程、升级设备、实施实时数据监控等措施,能明显减少能源消耗和有害排放,此外,自动化也带来了操作安全性的提升和生产效率的增加。尽管存在技术和经济的挑战,但通过策略性的投资,企业能有效克服这些障碍,实现长远的环境和经济双重利益。

新能源汽车空调热泵技术应用探讨

新能源汽车与国家节能减排的指导战略一致,在能源日益紧张的今天,即可解决民众出行对交通工具的需求,同时可减少车辆运行中对资源的消耗,也不会出现严重的环境污染问题,所以在未来有较大的发展潜力。制冷与制热是汽车空调的主要功能,传统燃油车的制冷制热技术已可非常成熟地利用燃油资源。然而,以往燃油车因技术的限制,虽然可进行制冷与制热的操作,但是存在较大的问题,比如能源利用率低,与我国能源战略的初衷相悖。新能源汽车具有无污染、零排放等优点,新能源汽车空调热泵技术的运用,可显著提高新能源汽车的综合性能,所以该技术在新能源汽车领域备受关注。本文对新能源热泵空调系统的工作模式及热泵空调技术应用状况进行探讨分析,梳理空调热泵的应用内容,探讨其在未来面临的发展机遇及面临的挑战。

热电发电技术回收工业余热分析

工业余热资源形式多样且总量巨大,节能潜力可观。利用热电发电技术将工业余热资源转化为电能,既能提升能源利用率又可以降低热污染,是实现双碳目标的重要技术途径。介绍了工业中不同类型余热的分布占比情况和热电发电的基本原理,重点对热电发电技术在工业领域中的应用研究进展进行了综述,并针对热电发电技术以及该技术在工业应用中存在的一些问题进行了分析、总结和展望。

CFETR核聚变发电厂储热技术对比

为解决核聚变发电热功率输出不稳定性和汽轮发电机组平稳运行之间的矛盾,中国聚变工程实验堆(China Fusion Engineering Test Reactor,CFETR)核聚变发电厂可运用储热技术对核聚变堆的功率输出进行削峰平谷。储热技术有多种类型,各类储热技术对于核聚变发电厂的适用性亟须进行对比。本文选取核聚变反应堆氦冷陶瓷增殖包层的参数作为储热技术边界条件,通过对储热技术适用温度范围进行评估,初步分析出有潜力运用于CFETR核聚变发电厂的三种储热技术,并对其进行成本初步预测。三大类储热技术均可选出适用CFETR核聚变发电厂氦冷增殖包层温度参数的储热介质。但化学储热由于其吸热和放热存在温差,不利于系统的稳定性及造成能量的损耗,显热储热技术和相变储热技术吸热温度和放热温度温差较小,具有应用于CFETR核聚变发电厂的潜力。初步经济性分析结果显示:相变储热成本最低,其次为熔融盐储热,再次为固相显热储热技术中利用硅砖作为储热介质,固相显热储热技术中利用铸钢作为储热介质成本最高。储热技术中,熔融盐储热技术、相变储热技术、固相显热储热具有应用于核聚变发电厂氦冷增殖包层的先决条件。熔融盐储热技术成熟度较高,有大量工程应用,造价在相变储热和固相显热储热之间,运用潜力较大。相变储热的成本最低,参数适用于核聚变发电,但其技术成熟度较低,有望成为未来研究的重点。

相变微胶囊保温砂浆的制备及性能

为减少建筑物的能耗,响应“碳中和”“碳达峰”国家政策,本工作基于原位聚合法,以正十八烷-正二十烷混合物为二元相变芯材,甲基丙烯酸甲酯(PMMA)为外层壁材,制备了一种适用于保温节能水泥砂浆的相变微胶囊(MiPCM)。MiPCM通过内部芯材在相变过程中吸热或放热的特性,降低外界环境对水泥砂浆内部温度的影响,从而减少人们对空调等电器的依赖程度,达到节能减排的目的。MiPCM呈球霰状,无团聚现象,具备明显的芯-壁结构,其相变温度区间和潜热分别为17.8~36.7℃和74.72 J/g。TG分析和热循环试验结果表明,MiPCM具备良好的热稳定性。将MiPCM掺加到水泥砂浆中进行温升实验。结果表明,在红外热源照射环境中,MiPCM明显减缓了水泥砂浆中心温度的变化速率,水泥砂浆石的峰值温度降低了7℃。因此,以MiPCM为外加剂的水泥砂浆符合保温节能的设计理念。