Process Integration and Opportunities for Heat Pumps in Industrial Processes

Abstract

Process integration methods allow one optimizing industrial processes. The main goals are decreasing energy demand and operating costs as well as reducing pollutants emissions. High fuel costs promote installations of heat pumps. In a heat pump, process waste heat is valorized by electrical power to produce higher quality heat. This energy is used to satisfy a part of the process demand so that less fuel is required and CO 2 emission will decrease. Based on pinch analysis, this paper presents a methodology to identify heat pump opportunities in industrial processes. The method considers the whole process including utilities and the energy conversion system. A combined analysis which considers thermal and material streams in the process is realized to optimize the heat recovery and the integration of energy conversion units. By analogy, all water streams are listed and the potential of water recuperation is also calculated. The combination of appropriate refrigeration and heat pump cycles leads to an important energy saving potential. The respective flow rates are defined by optimization. The application case of a typical dairy process is used to calculate the energy and operating cost savings potential as well as its corresponding investment costs and payback rates.

A new methodology combining total site analysis with exergy analysis

“…Usually, heat pumps can upgrade heat having its source at the ambient temperature, but if the process rejects heat at a higher temperature, then the heat pump can be coupled to the process with a higher performance since the temperature lift will be smaller. Kemp (2007) states that the appropriate placement of a heat pump should be across the plant's pinch, however, this is adapted according to the findings of Becker et al (2011) and Thibault et al (2014) to accommodate for pseudo pinch points.…”

A Multi-Objective Optimization Method to integrate Heat Pumps in Industrial Processes

“…1 (1)), is solved. The complete formulation can be found in Becker et al (2011). The yearly operating costs (OpC) are defined in Eq.…”

“…This approach could lead to non-realistic solutions, due to the fact that generally, industrial heat pumps work with one condenser and one evaporator. In Becker et al (2011), a methodology to estimate the potential of heat pump integration based on pinch analysis is reported. In the frame of an optimization process, it considers heat recovery between process streams together with the integration of energy conversion systems.…”

Multi-objective optimization on a heat exchanger network retrofit with a heat pump and analysis of CO2 emissions control

“…The results indicated that the integration of a heat pump with the process stream as the heat source can achieve greater energy savings in the process system. After analyzing the potential of an industrial heat pump integrated into the process [13], Becker et al [14] studied the effects of direct and indirect integration of a heat pump on energy savings in the system. The results showed that direct heat transfer between the working fluid and process streams can achieve better energy efficiency.…”