Synthesis of large‐scale heat exchanger networks using a T‐Q diagram method

Abstract

For design of a heat exchanger network (HEN) by pinch technology, it is not uncommon to determine stream splitting and stream matching by empirical experience, in which numerous attempts are usually required to reach the final configuration of the HEN. In this work, a novel T‐Q diagram method is proposed to integrate large‐scale HENs on the basis of partitioning and merging heat recovery intervals. It aims at reducing the difficulties of the stream matching process for large‐scale HENs. The implementation procedure is illustrated via a simple HEN design problem. Furthermore, the HEN of a vacuum distillation unit in a refinery is used to further demonstrate the advantages and versatility of the proposed method. The results indicate that the proposed method can reduce the computational effort required and obtain a cost‐effective design of large‐scale HENs. Therefore, it provides an effective graphical analysis tool for the integration of large‐scale HENs in practice.

A novel modelling method for plate heat exchanger to predict the outlet cooling water temperature

“…For a time period L, conditional variances for the samples in this period fŝ 2 ejxnew;s g s¼1;...;L can be calculated. If all the conditional variances fŝ 2 ejxnew;s g s¼1;...;L exceed the statistic limitŝ 2 con , the KPLS model updating is carried out using the latest training data, which include L new samples and exclude the L oldest samples.…”

“…T he plate heat exchanger (PHE), which plays a major role in the circulating cooling water system, is widely used in different fields including chemical industries, food and pharmaceutical industries, electricity generating stations, and steel plants. [1,2] The PHE is originally designed to be used in hygiene such as in the pasteurization of liquid food products. [3] However, in recent years it has been used in various fields due to its compact structure, superior performance in terms of heat transfer, and convent maintenance.…”

“…The plate heat exchanger (PHE), which plays a major role in the circulating cooling water system, is widely used in different fields including chemical industries, food and pharmaceutical industries, electricity generating stations, and steel plants . The PHE is originally designed to be used in hygiene such as in the pasteurization of liquid food products .…”

Synthesis of stream‐split heat exchanger networks using non‐structural model considering serial equipment in stream branches and submixing of substreams

“…Stream splitting is usually performed if, for a given problem, there are not enough hot (or cold) streams to exchange heat with cold (or hot) streams, respectively. The strategy is noticeable in early HEN design approaches based on thermodynamics laws such as the most prominent pinch method, [5] whose insights have also recently been used to realize largescale grassroots HEN designs [6] and retrofit designs. [7] Stream splitting can provide several structural possibilities and flexibilities for manipulating the mainstream and substream flows, stream temperatures, exchanger loads, and numbers of heat transfer units, with an overall effect that can influence energy recovery in HENs.…”

“…Stream splitting is usually performed if, for a given problem, there are not enough hot (or cold) streams to exchange heat with cold (or hot) streams, respectively. The strategy is noticeable in early HEN design approaches based on thermodynamics laws such as the most prominent pinch method, [ 5 ] whose insights have also recently been used to realize large‐scale grassroots HEN designs [ 6 ] and retrofit designs. [ 7 ]…”