&lt;b&gt;Energetic analysis of a commercial absorption refrigeration unit using an ammonia-water mixture

Araújo, Josegil Jorge de; Santos, Carlos Antônio Cabral; Holanda, Carlos Almir de; Duarte, João Batista Furlan; Ochoa, Álvaro; Dutra, José Carlos Charamba

doi:10.4025/actascitechnol.v39i4.29904

Cited by 13 publications

(10 citation statements)

References 25 publications

(27 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In this context, the use of plate exchangers as a basic component in heat and mass transfer was highlighted, where a flat plate heat exchanger [126,129] was studied to reduce the cost and size of the absorption chiller. In these studies it was noticed that even with the use of the alternative NH 3 /LiNO 3 mixture [20,40,121,125,130] and improvements in the overall performance of the absorption chiller [62,81], compared to ARS that use NH 3 /H 2 O [10,11,59,106], the problem of the viscosity of the mixture still represented an energy limitation, as established in the literature [95,125,130,131]. This led to the addition of water in the LiNO 3 absorber as a way to minimize these limitations.…”

Section: Final Considerations On the Absorption Refrigeration Systems...mentioning

confidence: 99%

“…In commercial manufacturing products, two types of solution pairs are commonly used: lithium bromide/water (LiBr/H 2 O) [7,8] and ammonia/water (NH 3 /H 2 O) [9][10][11]. Usually, the pair LiBr/H 2 O is used for thermal comfort systems and the pair NH 3 /H 2 O for refrigeration systems [12].…”

Section: Introductionmentioning

confidence: 99%

“…For the NH 3 /LiNO 3 mixture, Figure 16 shows the COP values for a single-, double-, triple-effect chiller, and the COP values of the advanced modified absorption chiller, respectively [11,16,17,41,42,[45][46][47][49][50][51][52]55,56,58,59,64,69,80,88,90,92,93,101,125,130,131]. The results are coherent with the conventional COP values of the single effect absorption chiller, which are 0.6-0.7, but the most important fact is that those values were obtained with driving temperatures (60-90 • C), which suits the use of solar energy as an input source.…”

mentioning

confidence: 99%

“…Figure 18. Summary of the driving temperature for each of the three working fluids (NH 3 /H 2 O, NH 3 /LiNO 3 , and NH 3 /LiNO 3 + H 2 O) for each of the four technologies (single, double, triple, and advanced technology).For the NH 3 /H 2 O single-effect absorption chiller[11,[57][58][59]63,100,105,114,122,140], Figure16, shows that the COP values of the single-effect absorption chiller vary up to 0.7, which represents the common values, considering driving temperature among 50-200 • C. For some references, the values between 50 and 100 • C showed a good fit for using solar energy as an input source of the ARS. However, for values beyond 100 • C, it could be a limitation since, for high-temperature values, the COPs are low, around 0.35.According to advanced technology, higher values for the COP could be found for NH 3 /H 2 O chillers, as presented in Lu et al[141].…”

mentioning

confidence: 99%

“…This prototype was built with an intermediary process to increase the system's performance to attend the residential district heating's thermal demands because conventional absorption heat pumps undergo significant performance deterioration at low ambient temperatures. This prototype with an intermediate process could offer up to 30 kW heating capacity to heat the water, leading to an increased coefficient of performance around 1.66 (Figure16).For the NH 3 /LiNO 3 mixture, Figure16shows the COP values for a single-, double-, triple-effect chiller, and the COP values of the advanced modified absorption chiller, respectively[11,16,17,41,42,[45][46][47][49][50][51][52]55,56,58,59,64,69,80,88,90,92,93,101,125,130,131]. The results are coherent with the conventional COP values of the single effect absorption chiller, which are 0.6-0.7, but the most important fact is that those values were obtained with driving temperatures (60-90 • C), which suits the use of solar energy as an input source.The COP values for the double-effect absorption chillers proposed in the literature are similar to the conventional ARS (LiBr/H 2 O and NH 3 /H 2 O) but have lower driving temperatures.…”

mentioning

confidence: 99%

See 4 more Smart Citations

Absorption Refrigeration Systems Based on Ammonia as Refrigerant Using Different Absorbents: Review and Applications

et al. 2020

View full text Add to dashboard Cite

The interest in employing absorption refrigeration systems is usually related to electricity’s precariousness since these systems generally use thermal rejects for their activation. The application of these systems is closely linked to the concept of energy polygeneration, in which the energy demand to operate them is reduced, which represents their main advantage over the conventional vapor compression system. Currently, the solution pairs used in commercial absorption chillers are lithium bromide/water and ammonia/water. The latter pair has been used in air conditioning and industrial processes due to the ammonia operation’s low temperature. Few review papers on absorption chillers have been published, discussing the use of solar energy as the input source of the systems, the evolution of the absorption refrigeration cycles over the last decades, and promising alternatives to increase the performance of absorption refrigeration systems. There is a lack of consistent studies about designing requirements for absorption chillers, so an updated review covering recent advances and suggested solutions to improve the use and operation of those absorption refrigeration systems using different working fluids is relevant. Hence, this presents a review of the state-of-the-art of ammonia/absorbent based absorption refrigeration systems, considering the most relevant studies, describing the development of this equipment over the years. The most relevant studies in the open literature were collected to describe this equipment’s development over the years, including thermodynamic properties, commercial manufacturers, experimental and numerical studies, and the prototypes designed and tested in this area. The manuscript focuses on reviewing studies in absorption refrigeration systems that use ammonia and absorbents, such as water, lithium nitrate, and lithium nitrate plus water. As a horizon to the future, the uses of absorption systems should be rising due to the increasing values of the electricity, and the environmental impact of the synthetic refrigerant fluids used in mechanical refrigeration equipment. In this context, the idea for a new configuration absorption chiller is to be more efficient, pollutant free to the environment, activated by a heat substantiable source, such as solar, with low cost and compactness structure to attend the thermal needs (comfort thermal) for residences, private and public buildings, and even the industrial and health building sector (thermal processes). To conclude, future recommendations are presented to deal with the improvement of the refrigeration absorption chiller by using solar energy, alternative fluids, multiple-effects, and advanced and hybrid configurations to reach the best absorption chiller to attend to the thermal needs of the residential and industrial sector around the world.

show abstract

Section: Final Considerations On the Absorption Refrigeration Systems...mentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

mentioning

confidence: 99%

mentioning

confidence: 99%

mentioning

confidence: 99%

See 3 more Smart Citations

Absorption Refrigeration Systems Based on Ammonia as Refrigerant Using Different Absorbents: Review and Applications

et al. 2020

View full text Add to dashboard Cite

show abstract

Theoretical and Experimental Study of the Effective Operation Mode of Absorption Refrigeration Chiller for Ice Production

Nguyen

Hoang

2022

The AUN/SEED-Net Joint Regional Conference in Transportation, Energy, and Mechanical Manufacturing Engineering

View full text Add to dashboard Cite

Combined energetic and exergetic assessment of a biomass-based integrated power and refrigeration plant

Chattopadhyay

Ghosh

2018

J Braz. Soc. Mech. Sci. Eng.

View full text Add to dashboard Cite

In this study, an integrated power and refrigeration plant, based on biomass gasification, has been modeled and analyzed. The producer gas generated by gasification of solid biomass undergoes full combustion in a combustor-heat exchanger (CHX) and heats up compressed air for an indirectly heated gas turbine (GT) cycle. The waste heat of the CHX exhaust is further recovered in a recovery boiler to produce steam for the generator of an absorption refrigeration (VAR) unit. Energetic and exergetic assessments have been performed for this integrated plant. Major plant parameters, viz. GT cycle pressure ratio and turbine inlet temperature were varied to find optimized plant configuration. The results show that at a GT cycle pressure ratio 10, the plant yields highest electrical efficiency of 27% when the GT inlet air temperature is 1100°C. At this point, the plant has the lowest cooling-to-power ratio (CTPR, value being 1.18), although this point also gives best exergetic performance; with a combined exergetic efficiency of 27.6%. The plant also gives lowest exergetic specific biomass consumption of 0.7 kg/kWh and highest fuel energy savings ratio of about 45% at the same point.

show abstract

<b>Energetic analysis of a commercial absorption refrigeration unit using an ammonia-water mixture

Cited by 13 publications

References 25 publications

Absorption Refrigeration Systems Based on Ammonia as Refrigerant Using Different Absorbents: Review and Applications

Absorption Refrigeration Systems Based on Ammonia as Refrigerant Using Different Absorbents: Review and Applications

Theoretical and Experimental Study of the Effective Operation Mode of Absorption Refrigeration Chiller for Ice Production

Combined energetic and exergetic assessment of a biomass-based integrated power and refrigeration plant

Contact Info

Product

Resources

About