Influence of Temperature Parameter Change on Lithium Bromide Absorption Heat Pump Performance

2013 ◽  
Vol 291-294 ◽  
pp. 1670-1674
Author(s):  
Biao Li ◽  
Jiang Fan

It is the new way of the thermal power plant energy conservation to recycling plant circulating water waste heat for heating with the heat pump technology. The recovery of low temperature waste heat is the background. And lithium bromide absorption heat pump is the object of this study. The impact of changes in temperature parameters on the performance of heat pump unit is analyzed. As a theoretical basis for the design of the heat pump system and power plant heat pump unit’s optimal operation provide a reference. The result provides a theoretical reference for the optimal operation of the heat pump system design and power plant heat pump units.

2010 ◽  
Vol 121-122 ◽  
pp. 986-991
Author(s):  
Jing Gang Wang ◽  
Xiao Xia Gao ◽  
Bo Liang ◽  
Hua Hui Zhou

A large number of cooling water exists in chemical plant, use water source heat pump and lithium bromide absorption heat pump system to achieve water cooling instead of cooling tower, at the same time, extract heat for building cooling and heating. Respectively introduced the summer cooling system and winter heating system, and a feasibility analysis was carried out. The conclusion is get: water source heat pump system and lithium bromide absorption heat pump system for cooling water waste heat recovery is certain feasibility; the environment optimization can be achieved in chemical plant, at the same time, energy conservation and emission reduction is realized.


Author(s):  
Muhammad Kashif Shahzad ◽  
Yaqi Ding ◽  
Yongmei Xuan ◽  
Neng Gao ◽  
Guangming Chen

Open absorption heat pump (OAHP) system is more viable option to recover waste heat from moist gas as compared to the traditional condensation methods. This promising technology has great potential for latent heat recovery from moist gas, drying process in paper and other industrial heating applications. This study presents the process modelling and comparative analysis of OAHP system in Aspen Plus using two different solutions by adopting part regeneration technique. The promising potassium formate-water (HCOOK/H2O) which has lower causticity, lower costs and better crystallization characteristics is used as an alternative to the caustic lithium bromide-water (LiBr/H2O) solution in this study. Process model of the system is established in Aspen Plus and, the properties validity is confirmed with published experimental and Engineering Equation Solver (EES) library data. A detailed comparative parametric study is carried out to evaluate the effect of influencing parameters on coefficient of performance (COP), water recovery (φ) and heat recovery (ζ) efficiencies. The performance of OAHP system is found to be very similar using different concentrations as 2.13 COP value for 50% LiBr/H2O and 2.19 for 70% HCOOK/H2O solution over design conditions. Similarly, φ is found to be 0.701, 0.688 while ζ as 0.716 and 0.705 for both the absorbents. Moreover, the system’s operational concentration range is 45-61.3% for LiBr/H2O and 55-82.1% for HCOOK/H2O at 135 °C regeneration heat input. Potassium formate solution having quite similar properties to the aqueous lithium bromide is also confirmed to have similar performance trends using 50% and 70% concentrations.


Author(s):  
Sufen Li ◽  
Lanhua Dai ◽  
Yan Shang

The ground source heat pump system (GSHP) continuous operation will result in heat accumulation of the soil around the underground heat exchangers leading the descend operation performance of heat pump system. Based on experiment of GSHP system in summer season, the temperature distribution of humid soil around the vertical boreholes, the power consumption of the heat pump unit, the water temperature in the inlet and outlet of the underground heat exchangers, the heat release rate of per unit length of the buried pipes in humid soil and the cooling coefficient of performance (COP) for the heat pump unit were acquired during the different intermittent heat storage modes. This study investigated the impact of soil temperature change around the borehole wall on the performance of heat pump operation, the influence of intermittent heat storage on the soil temperature near the borehole wall and the performance of heat pump unit, and the effect of intermittent heat storage process on the recovery rate of soil temperature. The results showed that proper control of the operation and interval time of GSHP can effectively improve the soil temperature field around the underground heat exchangers and enhance the performance of GSHP system, thus achieving high efficiency operation of heat pump units.


2021 ◽  
Vol 256 ◽  
pp. 02011
Author(s):  
Ze Wang ◽  
Honghong Shen ◽  
Qunyin Gu ◽  
Daoyuan Wen ◽  
Gang Liu ◽  
...  

The use of heat pump technology to recover the waste heat of circulating water from the power plant instead of steam extraction for heating can not only improve the thermal efficiency of the unit and reduce the loss of cold source, but also has great advantages in energy saving. This paper uses absorption and compression heat pumps to recover the waste heat of circulating water in the power plant to study its energy-saving benefits. Under the same heating load, the economics of the two heat pumps are calculated and analyzed. The results show that the energy-saving benefits of absorption heat pump units are far greater than compression units. But in terms of water saving, the water saving capacity of the compression heat pump unit is higher than that of the absorption heat pump.


Energies ◽  
2021 ◽  
Vol 14 (12) ◽  
pp. 3511
Author(s):  
Ali Khalid Shaker Al-Sayyab ◽  
Joaquín Navarro-Esbrí ◽  
Victor Manuel Soto-Francés ◽  
Adrián Mota-Babiloni

This work focused on a compound PV/T waste heat driven ejector-heat pump system for simultaneous data centre cooling and waste heat recovery for district heating. The system uses PV/T waste heat as the generator’s heat source, acting with the vapour generated in an evaporative condenser as the ejector drive force. Conventional and advanced exergy and advanced exergoeconomic analyses are used to determine the cause and avoidable degree of the components’ exergy destruction rate and cost rates. Regarding the conventional exergy analysis for the whole system, the compressor represents the largest exergy destruction source of 26%. On the other hand, the generator shows the lowest sources (2%). The advanced exergy analysis indicates that 59.4% of the whole system thermodynamical inefficiencies can be avoided by further design optimisation. The compressor has the highest contribution to the destruction in the avoidable exergy destruction rate (21%), followed by the ejector (18%) and condenser (8%). Moreover, the advanced exergoeconomic results prove that 51% of the system costs are unavoidable. In system components cost comparison, the highest cost comes from the condenser, 30%. In the same context, the ejector has the lowest exergoeconomic factor, and it should be getting more attention to reduce the irreversibility by design improving. On the contrary, the evaporator has the highest exergoeconomic factor (94%).


1999 ◽  
Author(s):  
D. A. Kouremenos ◽  
E. D. Rogdakis ◽  
G. K. Alexis

Abstract Absorption system have been investigated for many years. However, coefficient of performance COP or heat gain factor HGF for absorption systems are significantly lower than those for conventional compression systems. This has restricted their wide application. This paper discusses the behavior of mixture NH3-H2O through of an ejector, operating in an absorption heat pump system. This combination improves the performance of conventional absorption system and with the phasing out of ozone-damaging refrigerants, absorption refrigerators, heat pumps and air-conditioning now provide a potential alternative. For the detailed calculation of the proposed system a method has been developed, which employs analytical functions describing the thermodynamic properties of die mixture. The influence of three major parameters: generator, condenser and evaporator temperature, on ejector efficiency and heat gain factor of the system is discussed. Also the maximum value of HGF was estimated by correlation of above three temperatures.


2012 ◽  
Vol 608-609 ◽  
pp. 1241-1245
Author(s):  
Wei Qiu ◽  
Li Zhang ◽  
Qing Rong liu

This paper analyses the energy consumption of water source heat pump, shows that the performance coefficient of water source heat pump unit is directly related to the temperature of water resources, and discusses the feasibility of central heating by recovering condensing heat of power plant using water source heat pump unit. It analyzes the energy saving benefit of water source heat pump unit is significant compared with traditional heating. Using the technology recovers waste heat of power plant, which can not only decrease the energy waste on the direct discharge of waste heat and water, but at the same time, it is a new air conditioning system without environmental pollution.


Sign in / Sign up

Export Citation Format

Share Document