Medium Temperature Heat Research Articles

Heating Ceiling System Efficiency in Different Climate Zones

Abstract There are many benefits of building construction with prefabricated thermo active ceilings technology, and the most highlighted are: short lead time, ease of installation, low price, lack of taking up space in a room and additionally the possibility of working in heating and/or cooling mode. An analysis was carried out to illustrate the factors that influence the thermal output of a ceiling heating system in residential buildings located in 5 climate zones in Poland and 2 in Ukraine. The thermal loads were determined for the entire building, designed in accordance with the regulations in force in each country, for the flats and particular rooms (considering the heat exchange between the flats according to PN-EN 12831:2006). An average heating medium temperature of 34°C was assumed. The results were compared with the achievable heating capacity of the ceiling system, which results from the difference between the heating medium temperature and the indoor room temperature. It was investigated that the system achieves the calculated output in all climate zones in Poland, while it will not be sufficient in Ukraine. This is due to both less stringent building thermal protection regulations and different indoor design temperature values, resulting in a higher average temperature in the flat. When analysed on a room-by-room basis, it became apparent that in all considered locations there were rooms for which the heating capacity was insufficient. In the climate zones I to IV in Poland, the problem concerns only bathrooms, where in this case quite often the surface heating can be combined with a supplementary electric radiator. In the V climate zone in Poland and both in Ukraine, the solution to the power shortage under design conditions may be: building construction according to a higher energy standard, increasing the supply temperature (with the limitation of maximum ceiling surface temperature to 35°C for living spaces) or using additional heating elements not only in bathrooms. A novel part of the article discusses calculated power shortages in relation to climate change and the external design temperatures suggested by sources other than the standard.

Simple Empirical Relation for an Evacuated-Tube Solar Collector Performance Prediction from Solar Intensity

In this paper, the effect of solar intensity on the heat pipe tip temperature in a heat pipe type—evacuated-tube solar collector (HP-ETSC) was investigated. A simple relation was proposed, relating the solar intensity to the heat pipe tip temperature generated from the experimental data. This simple empirical relation was applied in a set of heat transfer equations derived to predict the heating medium temperature at the manifold outlet of the evacuated-tube solar collector. The calculated results corresponding to two types of heating medium, i.e., palm oil and water, were compared with experimental results from the literature. The results show that the average error was 6.41% for the case of palm oil and 4.66% for the case of water. Based on the case of water as a heating medium fluid, it was found that the flow rate of the heating medium fluid affected the accuracy of prediction, as the percentage error increased with the heating medium flow rate. The maximum percentage error increased from only 1.83% for a water inlet flowing at a Reynolds number of about 2.4 × 103 to 15.23% for a water flow rate at a Reynolds number of about 2.6 × 104. The correction factor was added into the correlation to predict the heat transfer coefficients of heating medium fluids. With this correction factor, the maximum error could be reduced from 11.78% to 7.29% for the palm oil case and from 15.23% to 5.57% for the water case. The average errors corresponding to palm oil and water cases could be reduced to 0.74% and 1.26%, respectively.

Macro-encapsulation of metallic phase change materials with sacrificial density less than 3.5 % for medium-temperature heat storage

To solve the problems of volume thermal expansion and high chemical activity of metallic phase change materials (PCMs), this paper successfully prepared millimeter/centimeter-size durable Bi@Void@Kaolin macrocapsules. Fortunately, carbon powder clusters from the thermal decomposition of adhesive CMC gathered on the core PCMs, cleverly adding a reducing atmosphere into the capsules. In particular, the buffer voids of macrocapsules were created from the pores and gaps between the accumulated Bi powders, and the method of improving the bulk density of powder cores as core precursors by the cold isostatic pressing (CIP) technology solves the problem of excessive cavity volume. Thermal analysis indicates that after CIP treatment, the heat storage density of the Bi@Kaolin macrocapsule with the unpressurized powder core volume accounting for 50% can be increased by 18.4%–275.0 J/cm3, which is about 2.5 times the heat storage density of the common medium-temperature heat storage materials - concrete and NaCl, under the working temperature range of 240–300 °C. Solid-liquid PCMs need to sacrifice their density in exchange for the necessary cavity volume, therefore the “actual volumetric heat storage density” of PCMs should be specified. The results show that the proportion of sacrificial density of Bi PCM (i.e. the cavity rate of Bi-based macrocapsule) can reach the optimal value of 3.5%, its actual volumetric heat storage density can reach 558.9 J/cm3 at 240–300 °C. Surprisingly, all the Bi@Kaolin macrocapsules showed excellent cycling durability and thermal stability during 500 cycles under air atmosphere and subsequent 24 h overload-temperature oxidation tests.

Preparation and thermal properties of LiNO3-NaNO3-NaCl/EG composite heat storage material

Nitrate phase change materials (PCM) have important applications in the field of thermal energy storage, but their latent heat value is relatively low. A novel LiNO3-NaNO3-NaCl ternary molten salt with high latent heat was prepared and studied. LiNO3-NaNO3-NaCl/expanded graphite (EG) composite phase change material (CPCM) was prepared by using high thermal conductivity EG as the carrier adsorption material. The performance of PCM and CPCM were tested and analyzed. Compared with LiNO3-NaNO3, the newly prepared ternary nitrate-chloride mixed molten salt has a lower phase change temperature, a higher latent heat value, and a higher thermal decomposition temperature. At the same time, the supercooling degree of LiNO3-NaNO3-NaCl is about half lower than that of LiNO3-NaNO3. There is no chemical reaction between different molten salts or between mixed molten salts and EG. The mixed molten salt is uniformly dispersed into the pore structure of EG, and no agglomeration occurs. Both LiNO3-NaNO3-NaCl and LiNO3-NaNO3-NaCl/EG have good cyclic thermal stability. The addition of EG greatly improves the thermal conductivity of LiNO3-NaNO3-NaCl. When the addition ratio of EG is 20%, the thermal conductivity of ternary molten salt increases from 1.378 to 5.453 W/m·K. The phase change materials added with EG still have high latent heat of phase change. The results show that LiNO3-NaNO3-NaCl/EG has broad application prospects in medium temperature heat storage.

EFFECT OF FREQUENCY AND DURATION OF THERMOSONICATION ON THE PHYSICAL, CHEMICAL AND MICROBIOLOGICAL QUALITY OF COW'S MILK

Milk is a food product that contains many nutrients. Thermosonication is a method combining ultrasonic and medium-temperature heating that can be used as an alternative pasteurisation method because it can maintain the nutrients contained in milk while providing safety assurance for consumption. This study aimed to determine the effect of frequency and duration of thermosonication on the physical, chemical and microbiological quality of cow's milk. The experimental design used was a completely randomised design (CRD) with two factorials of frequency (20 and 22kHz) and duration of thermosonication (5, 10, 15 and 20 minutes). The data obtained were analysed with ANOVA and BNJ further tests at the 5% level. The best treatment was 22kHz frequency for 20 minutes with the results of viscosity 3.80 ± 0.000 cP, pH 6.8 ± 0.00, fat content 3.22 ± 0.00%, protein content 2.19 ± 0.01% and total bacteria 0.53 ± 0.67 log CFU/ml, and was able to reduce Escherichia coli bacteria by 2.95 log CFU/ml.

Construction of phase change n-Octadecane microencapsulated in carbon nanotubes-modified polymer for thermal management applications of finned heat sinks

The low thermal conductivity of organic shell-based phase change microcapsules severely limits their practical applications in thermal management of high-power-density electronic components. A novel microencapsulated phase change material (MPCM) was synthesized via suspension polymerization with n-Octadecane core shelled by aminated multiwalled carbon nanotubes-doped styrene–divinylbenzene copolymer (SDB/MWCNT-NH2). The chemical structure and micromorphology of the new microcapsules (MPCM/CNT) with various amounts of doped aminated multiwalled carbon nanotubes (MWCNT-NH2) were identified by the Fourier transform infrared spectroscopy and scanning electron microscopy. The thermal properties of various MPCM/CNT samples were analyzed based on the measurements of thermogravimetric analyzer, differential scanning calorimeter and thermal conductivity meter. The results indicated that the microcapsules with MWCNT-NH2 had good thermal stability, heat storage capacity and heat transfer properties. The thermal performance of the microcapsule samples in the low and medium temperature finned heat sink (FHS) was investigated and their thermal performance with that of bare FHS at four constant thermal loads of 5 W, 7 W, 10 W and 15 W was compared. The thermal performance was evaluated based on the time to setpoint temperature, heat dissipated and heat dissipation factors. Compared with the bare FHS, the FHS with the MPCM/CNT-2.5 sample (i.e., 2.5 wt% MWCNT-NH2) exhibited 17.70% longer operation time, 33.01% more heat dissipated, and 16.53% higher heat dissipation factor during heating at 10 W. This study aims to apply the phase change microcapsules modified with high thermal conductivity MWCNT-NH2 in medium and low temperature heat sinks to optimize the thermal management of high power density electronic components and improve the heat dissipation performance of heat sinks. The microcapsules with MWCNT-NH2 showed great potential for applications in thermal management of electronic components.

Self-supporting and flexible organic potassium terephthalate with controllable carbon layers in K-ion batteries

Herein, we report a self-supporting and flexible K2TP/MWNCTs/C anode material prepared by electrostatic spinning and controlled medium temperature heat treatment in potassium-ion batteries. The results show that the flexible carbon cladding and stably conductive network structure can facilitate the transport of K+ and electron. The as-synthesized K2TP/MWNCTs/C flexible anode can exhibit a high specific capacity of 150.6 mAh g−1 after 100 cycles at a current density of 50 mA g−1. These results are of significant to explore high-performance organic flexible devices.

Activation of the combustion of low-reactivity solid fuels with metal-rolling production waste

The effect of the addition of different amounts of metal-rolling production waste (metal scale in amount of 1–10 wt%) on combustion characteristics of low-reactive solid fuels (anthracite and semi-coke) was studied. XRD analysis of the metal scale identified Fe3O4 and Mn3O4 phases along with a cubic Fe phase. The characteristics of ignition and combustion of the samples were studied via thermal analysis and high-speed video recording at heating medium temperatures of 600–800 °C (with 100 °C step) using a combustion chamber. It was experimentally found that the addition of a metal scale, regardless of its weight content, increases the fuel reactivity, as evidenced by the drop in temperature of the onset of intense oxidation (ΔTi) by 2–32 °C and the decrease in the ignition delay time (Δτi) by 0.2–2.2 s. The metal scale additive also increases the fuel combustion rate, which was evidenced by the maximum rate of oxidation (Δwmax) increasing by 0.1–2.0 wt%/min and, hence, the temperature of the end of oxidation (ΔTf) reducing by 13–68 °C. Due to combustion intensification, the carbon content in ash decreased by 55 rel% on average. The amount of CO and NOx contained in gas-phase combustion products diminished as well.

Exergoeconomic evaluation of a novel multigeneration process using solar driven Kalina cycle integrated with gas turbine cycle, double-effect absorption chiller, and liquefied natural gas cold energy recovery

This study is motivated to propose, evaluate, and optimize a solar-based multigeneration system relying on consecutive heat integration. Here, a heliostat field is configured to collect solar power and supply high-temperature air toward a nitrogen-based Brayton cycle. Afterward, the output hot air is subjected to a Kalina cycle suitable for medium-temperature heat resumption. A double-effect absorption refrigeration cycle boosted by a Liquid-based natural gas cold energy recovery unit for power generation and natural gas regasification are the other subsystems. The principal purpose is to protect the energy level of the fluid evacuating the solar field and to minimize the irreversibility of the scheme since solar-based systems lead to major irreversibility. The designed process is apprised from a 3E perspective, including exergy, energy, and exergoeconomic analyses. In addition, a comprehensive sensitivity study is done based on the influence of effective factors on the exergy and energy efficiencies and unit cost of products. Eventually, a multi-objective optimization is performed to set the most suitable condition of decision parameters and reach the optimal unit cost of products and exergy performance (objective functions). To do optimization, a genetic algorithm is applied, and two decision-making approaches, i.e., LINMAP and TOPSIS, are regarded. The optimal objectives are gauged to be 24.76% and 15.90 $/GJ by TOPSIS and 24.47% and 15.73 $/GJ by LINMAP, respectively.

Thermodynamics and Structural Optimization of Organic Rankine Cycle Plant for Clean Energy Access Using Artificial Bee Colony and Multi-Criteria Decision-Making Algorithms

The quest to decarbonize the energy space to avert the negative climate change consequences calls for using low/zero-carbon energy conversion technologies in the energy generation space. The Organic Rankine Cycle is a low/zero-carbon energy conversion technology for recovering waste heat from low to medium-temperature heat sources and for biomass conversion. Therefore, this paper presents the thermodynamic optimization, with an artificial bee colony algorithm, of different ORC configurations, including simple organic Rankine cycle, Regenerative Organic Rankine Cycle, Cascade Organic Rankine Cycle, Organic Rankine Cycle with Superheat, Organic Rankine Cycle with Superheat and Reheat, Regenerative-Superheat Organic Rankine Cycle, Regenerative-Reheat Organic Rankine Cycle and Two Complementary ORC using twelve (12) different working fluids. The thermodynamic optimization was followed by structural optimization using a multi-criteria decision approach. The modified-TOPSIS multi-criteria decision-making analysis was used to perform the structural optimization. The overall optimization study shows that the Regenerative-Reheat Organic Rankine Cycle, operating with an isopentane of 0 GWP and ODP, was selected as the best ORC configuration. The Regenerative-Reheat Organic Rankine Cycle has the following performance; thermal efficiency of 49.5%, maximum power output of 0.4 MW, condenser pressure of 90 kPa, and turbine pressure of 3.37 MPa. The results presented in this work will support clean energy developers in the clean energy access sector, especially in the agrarian community with huge agro-waste generation potentials.

Unidimensional and 3D Analyses of a Radial Inflow Turbine for an Organic Rankine Cycle under Design and Off-Design Conditions

The organic Rankine cycle (ORC) is an efficient technology for electricity generation from low- and medium-temperature heat sources. In this type of power cycle, the radial inflow turbine is the option usually selected for electricity generation. As a critical ORC component, turbine performance markedly affects the efficiency of the system. Therefore, the challenge is to model the behavior of the radial inflow turbine operating with organic fluids for heat recovery applications. In this context, various groups of fluids are highlighted in the scientific literature, including R-123, R-245fa, and R-141b, which are the fluids used in this research. Since little research has focused on the turbine efficiency effect on the power cycle design and analysis, this study presents an analysis of a radial inflow turbine based on a mathematical model of a one-dimensional design of the turbine. From this analysis, geometric, thermal, and operating parameters were determined, as well as volute, stator, and rotor losses. For this purpose, an algorithm was implemented in MATLAB to calculate the one-dimensional parameters of the turbine. Using these parameters, a 3D model of the turbine was designed in ANSYS-CFX, with performance curves of each projected turbine under design and off-design conditions. The numerical results suggest that the isentropic efficiency of all the proposed turbines under design conditions can surpass 75%. Additionally, the findings indicate that different design conditions, such as specific speed, pressure ratio, and turbine size, can affect the efficiency of radial inflow turbines in ORC systems.

Experimental studies on LaNi4.25Al0.75 alloy for hydrogen and thermal energy storage applications

Reversible exothermic and endothermic reactions between metals/alloys and hydrogen gas provide great opportunity to utilize various thermal energy sources such as waste heat, industrial exhaust, and solar thermal energy. Metal hydrides with favourable properties to operate at medium temperature heat (about 150 °C) are limited, and studies on hydrides in this temperature range are scarce. Hence, the present study aims at experimental investigations on LaNi4.25Al0.75 alloy in the temperature range of 150 °C–200 °C. A novel cartridge type of reactor is employed to investigate the hydrogen storage characteristics and thermal storage performance of this alloy. LaNi4.25Al0.75 is found to have a hydrogen storage capacity of about 1.20 wt% at 10 bar and 25 °C. In addition, it can store a total thermal energy of 285.7 kJ.kgMH−1 and can deliver heat at an average rate of 287.5 W.kgMH−1 at an efficiency of 64.1%.

Activation of anthracite combustion by copper acetate: mechanism, effect of particle size and introduction method

This paper addressed the effect of copper acetate on the combustion characteristics of anthracite depending on the fractional composition of fuel and additive introduction method. Anthracite was impregnated with 5 wt% of Cu(CH3COO)2 by mechanical mixing and incipient wetness impregnation. Four anthracite samples of different fraction with d < 0.1 mm, d = 0.1–0.5 mm, d = 0.5–1.0 mm, and d = 1.0–2.0 mm were compared. According to EDX mapping, incipient wetness impregnation provides a higher dispersion of the additive and its uniform distribution in the sample. The ignition and combustion characteristics of the modified anthracite samples were studied by thermal analysis and high-speed video recording of the processes in a combustion chamber (at heating medium temperature of 800 °C). It was found that copper acetate increases anthracite reactivity, which was evidenced by decreased onset temperature of combustion (ΔTi) by 35–190 °C and reduced ignition delay time (Δτi) by 2.1–5.4 s. Copper acetate reduces fuel underburning (on average by 70%) in the ash residue of anthracite and decreases the amount of CO and NOx in gas-phase products (on average by 18.5% and 20.8%, respectively). The mechanism for activation of anthracite combustion by copper acetate is proposed.

A medium-temperature, tubeless heat exchanger based on alloy microencapsulated phase change material (MEPCM)/ceramic composites

High-performance heat storage materials and devices are urgently needed to meet the demand for efficient heat storage. Herein, a novel SnBi58 alloy microencapsulated phase change material (MEPCM)/ceramic composite with flow channels inside is fabricated for medium-temperature heat storage, which combines the characteristics of sensible heat storage (SHS) and latent heat storage (LHS). Then a tubeless heat exchanger based on the composite is constructed, and its heat storage performance is experimentally studied. The results show that the thermal conductivity of the composite-based heat exchanger is doubled (up to 3.09 W/(m·K)) and the heat storage density is increased by 30.4% to 559.1 MJ/m3 compared with the ceramic-based heat exchanger. Meanwhile, the heat storage performance of the heat exchanger can be improved with the increase of inlet temperature and mass flow rate, and it is more sensitive to the response of the inlet temperature. Furthermore, the average heat storage duty of the heat exchanger reaches 1183 W/(m3·°C), which is 3.56 times the mean value of other heat storage devices. Finally, test results confirm the high thermal reliability of the composite, which can meet the tubeless heat exchange requirements.

Innovations for organic Rankine cycle power systems: Current trends and future perspectives

Since the early 2000s, organic Rankine cycle (ORC) technology has experienced rapid development and market uptake. More than 4.5 GW of total ORC power plant capacity has been installed since then. Due to its flexibility, suitability for small- to medium-scale installations, its applicability to low- to medium-temperature heat sources, and compact design, ORC technology is already considered as state-of-the-art. However, to further increase the technical and economic potential of this technology, significant research is needed to further improve efficiency and other key performance indicators, as well as to address environmental and safety aspects. Therefore, it is important to research new technologies and to foster innovations for improving performance; but it is of similar importance to resolve operational challenges with applied research that focuses closer to the market, and the technology provider and user needs. This vision article outlines the current state-of-the-art and presents current research trends. Parts of this article summarize the research progress reported at the 6th International Seminar on ORC Power Systems (ORC2021) and accompanies the associated special issue published following this event. The article highlights research trends at the concept level, but also at the component and system levels and, therefore, provides a holistic overview for the interested reader regarding the current challenges and potential future research activities in this area. Beyond the variety of cycle concepts in Section 2.1, the different heat sources and applications in Section 2.2, rotating device and turbomachinery (pumps and expansion devices) options in Section 2.3, current R&D trends for working fluids are presented in Section 2.4. This editorial concludes with a more applied perspective on ORC systems, covering process control and a general perspective on the technology in Section 2.5. With an increasing number of ORC plants operating in the field, their integration within a wider energy system is also of increasing importance, and this is addressed in Section 2.6. All prior elements are levers toward the grand challenges in ORC technology: increasing efficiency, reducing investment costs, as well as increasing sustainability, environmental performance, and system compactness.

Life cycle greenhouse gas emissions of low-temperature process heat generation by external compound parabolic concentrator (XCPC) solar thermal array

New solar-based technologies are currently being developed as prospective low-carbon sources of heat for industry, which require life cycle assessment to determine their actual decarbonization potential relative to current heat sources. We performed the first life cycle assessment of the external compound parabolic concentrator (XCPC) solar array, a novel low-concentration and non-tracking solar thermal technology capable of providing low-to medium-temperature heat (up to 250 °C). Primary data on the materials and performance of the XCPC were used in this analysis. The embodied greenhouse gas (GHG) emissions associated with manufacturing the technology are 92.4 kg CO2eq/m2, cradle-to-gate. The life cycle GHG emissions cradle-to-grave over a 25-year lifetime under conditions in the Central Valley of California are 129.7 kg CO2eq/m2. On the basis of thermal energy delivered, the XCPC has a carbon footprint of 5.8 g CO2eq per kWhth. These results indicate that the XCPC can generate low temperature heat with a carbon footprint 97% lower than natural gas and 98% lower than propane combustion in regions of high solar insolation.

A novel composite phase change material of high-density polyethylene/d-mannitol/expanded graphite for medium-temperature thermal energy storage: Characterization and thermal properties

As pure phase change materials (PCM) filling in supporting porous material are often unfavorable for thermal energy storage (TES) due to the easy leakage, low thermal conductivity, and reduced overall latent heat, composite phase change materials (CPCMs) receive the increasing attention for the future applications. In this work, a novel medium-temperature CPCM was prepared by the method of melt adsorption-compression molding, which used d-mannitol (DM) as PCM, high-density polyethylene (HDPE) as supporting material, and expanded graphite (EG) as thermal enhancement material. The thermophysical properties of such CPCMs were measured and analyzed to identify the optimal material design. The results showed that the leaking of DM from the HDPE/DM composite can be avoided under the 30 % mass loading of HDPE, showing a better adsorption capacity. Among the prepared examples, the CPCM3 (26.4 % HDPE + 61.6 % DM + 12 % EG) has the highest thermal conductivity of 2.66 W/(m·K) which is 6.04 times higher than the pure HDPE/DM composite. The CPCM3 also has other favorable characteristics such as a constant melting temperature of around 163.2 °C, high latent heat of 224.1 J/g, supercooling degree of 37.4 °C, and decomposition temperature of 411.3 °C. The complex influencing mechanisms were further explored with the help of material microstructure characterization. This study is significant because it provides design guidelines for reliable medium-temperature heat storage materials for advanced renewable energy applications.

High temperature cascade heat pump system with double medium and low temperature heat sources

In response to the call for carbon neutrality and control of CO2 emission, this paper proposes a high temperature cascade heat pump system with double medium and low temperature heat sources. Compared with those with a single heat source, the new system has obvious advantages in energy saving and carbon emission. An experiment is designed where the temperature of medium temperature heat source keeps unchanged, revealing that, compared with a single low temperature heat source, the heating capacity of low temperature heat source reduces by 2.9%, the heating capacity of medium temperature heat source increases by 31.1%, the total power consumption of the heat pump increases by 3%, and the heating capacity of the heat pump increases by 4.3%.

Experimental study on high temperature heat pump system with a double heat source cascade

In order to improve the thermal performance of a high temperature heat pump system, to realize the efficient heat recovery of industrial waste heat, and to make the combined utilization of low and medium temperature heat sources, a high temperature heat pump system with a double heat source cascade is proposed, which can absorb heat from industrial waste heat and the system is capable of heating water up to the required high temperature. The performance of the system is tested and analyzed. It is found that the inlet temperature of the medium temperature heat source has a significant impact on the performance of the heat pump system under working mode of the medium and low temperature heat sources. When the inlet temperature of the intermediate temperature heat source rises from 42?C to 53?C, the heating capacity of the cascade heat pump increases by 18.6%, and its performance coefficient increases by 8.9%. This paper provides a reference for the high efficiency of the cascade high temperature heat pump technology.

Analysis of Different Organic Rankine and Kalina Cycles for Waste Heat Recovery in the Iron and Steel Industry.

This study analyzed waste heat of two sections including the rolling section and electric arc furnace with low and medium temperature ranges, respectively. Organic Rankine cycles (ORCs) and Kalina cycles are the best technologies for the conversion of low-quality and medium-quality thermal energy to electrical power. The ORC applies the principle of the steam Rankine cycle, but it uses organic working fluids with low boiling points to recover heat from lower temperature heat sources. Also, in the Kalina cycle, ammonia water is selected as the working fluid because of its variable boiling point and thermodynamic properties. This study employs the thermo-economic method using the genetic algorithm to optimize the performance of three different ORC systems including a basic ORC (BORC) system, a single-stage regenerative ORC (SRORC) system, and a double-stage regenerative ORC (DRORC) system using five different working fluids and a basic Kalina cycle with KCS34 and complex cycle under the same waste heat conditions. Based on the energy and exergy analysis, the complex Kalina cycle shows the best performance among all studied cycles. The next best performance was exhibited by KCS34 and DROC, respectively. In general, Kalina cycles and ORCs are suitable for low-temperature and medium-temperature heat sources, respectively. According to the thermo-economic analysis, KCS34 in the rolling section and DRORC in EAF show optimum performance for heat recovery. R11 and R113 are selected as the best working fluids for ORCs, and ammonia with a concentration of 0.9 in the mixture is the optimal solution for Kalina cycles.