Optimal coefficient of the share of cogeneration in the district heating system cooperating with thermal storage

Self Cite

The paper is devoted to explication of one of the advantages of heat and electricity cogeneration, rarely considered in technical literature. Usually attention is paid to the fact that heat losses of the heat distribution network are less severe in the case of cogeneration of heat in comparison with its separate production. But this conclusion is also true in other cases when the internal consumption of heat is significant. In this paper it has been proved in the case of two examples concerning trigeneration technology with an absorption chiller cooperating with a combined heat and power (CHP) plant and CHP plant integrated with amine post-combustion CO2 processing unit. In both considered cases it might be said that thanks to cogeneration we have to do with less severe consequences of significant demand of heat for internal purposes.

Section: Discussionmentioning

confidence: 99%

System effects of primary energy reduction connected with operation of the CHP plants

Ziębik

Gładysz

2017

Self Cite

“…Fazlollahi et al [8] have proposed a procedure for optimization in DH on the stage of design and operation. Ziębik and Gładysz [9] have proposed an empirical formula for determination of the optimal value of the share of cogeneration in cogeneration systems with thermal storages. There are many works about optimization and controlling seasonal storages (STES) [10,11].…”

Section: Current State Of Researchmentioning

confidence: 99%

Modeling of District Heating Networks for the Purpose of Operational Optimization with Thermal Energy Storage

Leśko

Bujalski

2017

The aim of this document is to present the topic of modeling district heating systems in order to enable optimization of their operation, with special focus on thermal energy storage in the pipelines. Two mathematical models for simulation of transient behavior of district heating networks have been described, and their results have been compared in a case study. The operational optimization in a DH system, especially if this system is supplied from a combined heat and power plant, is a difficult and complicated task. Finding a global financial optimum requires considering long periods of time and including thermal energy storage possibilities into consideration. One of the most interesting options for thermal energy storage is utilization of thermal inertia of the network itself. This approach requires no additional investment, while providing significant possibilities for heat load shifting. It is not feasible to use full topological models of the networks, comprising thousands of substations and network sections, for the purpose of operational optimization with thermal energy storage, because such models require long calculation times. In order to optimize planned thermal energy storage actions, it is necessary to model the transient behavior of the network in a very simple way -allowing for fast and reliable calculations. Two approaches to building such models have been presented. Both have been tested by comparing the results of simulation of the behavior of the same network. The characteristic features, advantages and disadvantages of both kinds of models have been identified. The results can prove useful for district heating system operators in the near future.

“…This arrangement feeding the district heating system. Such solutions are applicable to areas with access to the district heating system [21].…”

mentioning

confidence: 99%

Modular heat storage in waste heat recovery installations

2023

The paper presents the methodology of designing a system for accumulating waste heat from industrial processes. The research aimed to analyse the fluid's movement in the heat accumulator to unify the temperature field in the volume of water constituting the heat buffer. Using the computer program Ansys Fluent, a series of computational fluid dynamics simulations of the process of charging the heat storage with water at 60 • C, 70 • C, and 80 • C was carried out. The selected temperatures correspond to the temperature range of unmanaged waste heat. In the presented solution, heat storage is loaded with water from the cooling systems of industrial equipment to store excess heat and use it at a later time. The results of numerical calculations were used to analyse the velocity and temperature fields in the selected structure of the modular heat storage. A novelty in the presented solution is the use of smaller modular heat storage units that allow any configuration of the heat storage system. This solution makes it possible to create heat storage with the required heat capacity.