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Analysis of the use of waste heat from a glass melting furnace for electricity production in the organic Rankine cycle system

Musiał Arkadiusz Mateusz, Antczak Łukasz, Jędrzejewski Łukasz, Klonowicz Piotr

Archives of Thermodynamics

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2021

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Vol. 42, no 1

15--33

EN

In most production plants, waste heat is usually discharged into the environment, contributing to a reduction in the energy efficiency of industrial processes. This is often due to the low thermal parameters of the carriers in which this energy is contained, such as oils, water, exhaust gases or other post-process gases, which means that their use for electricity production in a conventional Rankine cycle may prove to be economically unprofitable. One of the technologies enabling the use of lowand medium-temperature waste heat carriers is the organic Rankine cycle (ORC) technology. The paper present results of calculations performed to evaluate potential electricity production in ORC using waste heat from a natural gas-fired glass melting furnace. The analysis was carried out assuming the use of a single-stage axial turbine, whose efficiency was estimated using correlations available in the literature. The calculations were carried out for three working fluids, namely hexamethyldisiloxane, dimethyl carbonate, and toluene for two scenarios, i.e. ORC system dedicated only to electricity production and ORC system working in cogeneration mode, where heat is obtain from cooling the condenser. In each of the considered cases, the ORC system achieves the net power output exceeding 300 kW (309 kW for megawatts in the cogenerative mode to 367 kW for toluene in the non-cogenerative mode), with an estimated turbine efficiency above 80%, in range of 80,75 to 83,78%. The efficiency of the ORC system, depending on the used working fluid and the adopted scenario, is in the range from 14.85 to 16.68%, achieving higher efficiency for the non-cogenerative work scenario.

2

The use of geothermal energy in co-generated heat and power production in Poland : a case study

Mróz Tomasz Maciej, Grabowska Weronika

Archives of Environmental Protection

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2021

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Vol. 47, no. 3

82--91

EN

The paper presents the results of energy and environmental evaluation of geothermal CHP plant. The variant of CHP plant based on Organic Rankine Cycle (ORC) has been taken into consideration as the most favorable for the geothermal conditions prevailing in Poland. The existing geothermal well located in the city of Konin in Greater Poland (Wielkopolska) voivodship has been chosen as the case study. The conceptual design of CHP plant has been proposed and evaluated from energy and environmental point of view. The non-renewable primary energy consumption has been chosen as energy performance criterion. In the case of environmental performance carbon dioxide emission has been taken as evaluation criterion. The analysis has been performed for different operating conditions and three working fluids. The best energy performance can be spotted for working fluid R123, for which the reduction varies between 15200 and 11900 MWh/a. The working fluid R134a has a worse energy performance, which allows for the reduction of fossil fuels energy consumption in the range of 15000 and 11700 MWh/a. The total reduction of CO2 emission is the highest for working fluid R123: 5300 to 4150 MgCO2/a, the medium one for working fluid R134a: 5200 to 4100 MgCO2/a and the lowest for working fluid R227: 5000 to 4050 MgCO2/a. It has been shown that the construction of geothermal CHP plants based on Organic Rankine Cycle can be reasonable solution in Polish conditions. It is important concerning the need of reduction of fossil fuels primary energy consumption and carbon dioxide emission.

3

Working Fluid Selection for Simple and Recuperative Organic Rankine Cycle Operating Under Varying Conditions: A Comparative Analysis

Igbong Dodeye, Nyong Oku E., Enyia James, Agba Ambrose

Advances in Science and Technology. Research Journal

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2021

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Vol. 15, no 4

202--221

EN

The selection of suitable working fluid for simple and recuperative organic Rankine cycle (ORC) operating under subcritical, superheated and supercritical conditions are investigated. 11 fluids with critical temperature above 1500C are considered as potential candidates. Performance screening parameters such as net power output, thermal efficiency, turbine sizing parameter (SP) and volumetric flow ratio (VFR), exegetic parameters like irreversibility rate, fuel depletion ratio, and improvement potential rate of exergy destruction were also evaluated. Results indicate that R600a, R236fa and R1233dz(E) demonstrated the best performance for subcritical, superheated and supercritical simple ORC, respectively. R236fa and R1233dz(E) proved more suitable for subcritical/superheated and supercritical recuperative cycles, respectively. The system exegetic efficiency is reveal to be significantly higher in subcritical/superheated (61-65%) cycles compared to the supercritical (35-45%) cycle, the evaporator seen as the main source of exergy destruction, accounting for 17-37% of inlet exergy destroyed and about 8-24% in the turbine.

4

Performance optimization of organic Rankine cycles for waste heat recovery for a large diesel engine

Ma Z., Wu J., Zhang Y.

Archives of Thermodynamics

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2018

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Vol. 39, no 1

3--23

EN

In order to recover the low grade waste heat and increase system fuel economy for main engine 10S90ME-C9.2-TII(part load, exhaust gas bypass) installed on a 10000 TEU container ship, a non-cogeneration and single-pressure type of waste heat recovery system based on organic Rankine cycle is proposed. Organic compound candidates appropriate to the system are analyzed and selected. Thermodynamic model of the whole system and thermoeconomic optimization are performed. The saturated organic compound vapor mass flow rate, net electric power output, pinch point, thermal efficiency and exergy efficiency varied with different evaporating temperature are thermodynamically analyzed. The results of thermodynamic and thermoeconomic optimization indicate that the most appropriate organic compound candidate is R141b due to its highest exergy efficiency, biggest unit cost benefit and shortest payback time.

5

Experimental investigation on a rotodynamic pump operating in the cogeneration system with a low-boiling working medium

Kaczmarczyk T., Żywica G., Ihnatowicz E.

Transactions of the Institute of Fluid-Flow Machinery

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2016

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nr 134

63--87

EN

The article presents the research carried out on the circulating rotodynamic pump (peripheral pump) operating in the organic Rankine cycle with or without regeneration. The low-boiling solvent HFE7100 was used as the working ﬂuid. Its boiling point is around 61 ◦C at atmospheric pressure. An expansion valve, which simulated the operation of an expansion machine, was used to load the tested pump. The ﬂow characteristics were given for the working media: a solution of glycol and HFE7100 in the condenser, thermal oil and HFE7100 in the evaporator and HFE7100 in the regenerator. The research results concerning the PK70 pump operating in an ORC cycle are reported for the HFE7100 temperature range 15-60 ◦C and the dynamic viscosity range of 0.132 to 0.66 mPas. The maximum ﬂow rate and pressure of the pump during its operation in the ORC system were assessed. The analysis of the results demonstrates that the maximum eﬃciencies of the pump operating with or without regeneration were 44% and slightly below 37%, respectively. The impact of the selected physicochemical parameters of the working mediums on the pressure drops occurring in the ORC cogeneration installation was discussed. Based on the research conducted and the measurement results, the possibility to apply a PK70 unit as a circulating pump for the working medium in an ORC cycle was checked.

6

On the efficient use of a lowtemperature heat source by the organic Rankine cycle

Mikielewicz D., Mikielewicz J.

Archives of Thermodynamics

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2013

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Vol. 34, no. 3

61--73

EN

The evaporation temperature is regarded as one of the major parameters influencing the organic Rankine cycle (ORC) efficiency. Majority of contributions in literature for ORC cycle analyses treat the heat source as if it had an infinite heat capacity. Such analyses are not valuable as the resulting temperature drops of the heat source needs to be small. That leads to the fact that the heat source is not well explored and in the case of waste heat utilization it can prove the poor economics of the ORC. In the present study cooperation of the ORC cycle with the heat source available as a single phase or phase changing fluids is considered. The analytical heat balance models have been developed, which enable in a simple way calculation of heating fluid temperature variation as well as the ratio of flow rates of heating and working fluids in ORC cycle. The developed analytical expressions enable also calculation of the outlet temperature of the heating fluid.