US-12618622-B2 - Prevention of microbiological growth in heat exchangers

Abstract

A heat exchanger assembly is proposed comprising: a heat exchanger forming one or more electrically connected partitions separating a first fluid and a second fluid. The assembly further comprises: a first electrical connector and a second electrical connector that are operationally connected to the partitions of the heat exchanger and an electrical power source operationally connected to the first electrical connector and the second electrical connector. The electrical power source is configured to supply an electric current to the one or more partitions of the heat exchange via the first electrical connector and the second electrical connector.

Inventors

• Thomas Andersson

Assignees

• ALFA LAVAL CORPORATE AB

Dates

Publication Date

20260505

Application Date

20250106

Priority Date

20191007

Claims (5)

1. 1 . A system for preventing microbiological growth in a heat exchanger, comprising a plurality of partitions separating a first fluid and a second fluid and through which heat can be transferred between the first fluid and the second fluid, wherein the partitions are electrically connected to one another, a first electrical connector and a second electrical connector adapted for operationally connecting to the plurality of partitions of the heat exchanger; and an electrical power source adapted for operationally connecting to the first electrical connector and the second electrical connector and configured to supply an electric current to the plurality of partitions of the heat exchanger via the first electrical connector and the second electrical connector, wherein the electrical power source is configured to supply an electric current for reducing growth of microorganisms on the plurality of partitions of the heat exchanger.
2. 2 . A method for reducing microbiological growth in a heat exchanger forming the plurality of partitions separating a first fluid and a second fluid and through which heat can be transferred between the first fluid and the second fluid, wherein the partitions are electrically connected to one another, the method comprising: providing a system according to claim 1 ; operationally connecting the first electrical connector and the second electrical connector to the plurality of partitions of the heat exchanger; and supplying an electric current to the plurality of partitions of the heat exchanger with the electrical power source.
3. 3 . The method of claim 2 , further comprising providing a flow of the first fluid and a flow of the second fluid in the heat exchanger.
4. 4 . The system of claim 1 , wherein an electric circuit is formed by the first electrical connector extending from the electrical power source to a first partition of the plurality of partitions and the second electrical connector extending from a second partition of the plurality of partitions to the electrical power source or ground.
5. 5 . The system of claim 4 , wherein the first partition and the second partition are electrically connected to one another by an electrically conductive connector or support.

Description

CROSS-REFERENCE TO RELATED APPLICATION This application is a Continuation Application of Ser. No. 17/766,579, filed on Apr. 5, 2022, which is the National Phase application under 35 U.S.C. § 371(c) of International Application No. PCT/EP2020/077902, filed Oct. 6, 2020, which claims priority from European Application No. EP 19201662.4, filed Oct. 7, 2019, and Swedish Application No. SE 2050606-9, filed May 26, 2020, all of which are hereby expressly incorporated by reference into the present application. TECHNICAL FIELD The proposed technology relates generally to the field of heat exchangers. It relates specifically to plate heat exchangers and heat exchangers in marine applications. The technology also relates to the prevention of the growth of microorganisms on the inside surfaces of heat exchangers. BACKGROUND Heat exchangers are systems that are used to transfer heat between two or more fluids. Typically, the fluids are separated by a solid partition to prevent mixing. Heat exchangers are used in both cooling and heating processes. Microbiological growth in heat exchangers is a recognized problem. Such growth can negatively affect the performance of the heat exchanger, for example with respect to flow rates and heat conductance. Microbiological growth is particularly a problem in marine applications, in which sea water is supplied to the heat exchangers. Sea water can be high in nutrients and the temperature of the supplied sea water is often within a range that is favorable for microbiological growth. Liquid food products, such as beverages and liquid dairy products, also have a high nutrient content. Heat exchangers used in the processing of such products typically have high rates of microbiological growth and require a frequent cleaning to prevent a drop in quality of the product. Typically, the production must be interrupted for cleaning and chemicals are commonly used in the cleaning, which contributes to a decreased efficiency and increased production costs. The microbiological growth is particularly a problem in plate heat exchanger that cannot be disassembled for manual cleaning. OBJECT The proposed technology aims at preventing or reducing microbiological growth in heat exchangers, and in particular on the partitions of heat exchangers. It is also an object to reduce microbial growth in heat exchanger used in the processing of liquid food products, and specifically in plate heat exchangers. SUMMARY In a first aspect of the proposed technology, a heat exchanger assembly is provided. The assembly comprises: a heat exchanger forming, or comprising, one or more partitions, or walls, separating, or configured to separate or keep distinct, a first fluid and a second fluid and through which heat can be transferred, or conducted, between the first fluid and the second fluid. The assembly further comprises: a first electrical connector and a second electrical connector that are operationally connected to the one or more partitions, or walls, of the heat exchanger. Additionally, the assembly comprises an electrical power source operationally connected to the first electrical connector and the second electrical connector and configured to supply an electric current, and/or an electric potential, to the one or more partitions, or walls, of the heat exchanger via the first electrical connector and the second electrical connector. A partition is here and throughout these specifications understood to encompass a wall. It is understood that the first aspect of the proposed technology is directed to a heat exchanger assembly for reducing, inhibiting, or preventing growth of microorganisms in the heat exchanger forming part of the assembly. Operationally connected is here understood to only specify that there is an electrical connection by which a current can be supplied. The first and second electrical connectors being operationally connected to the one or more partitions encompasses the connectors being operationally connected to each of the one or more partitions. It is also understood to encompass the electrical connectors being directly connected to the partitions, and the electrical connectors being directly connected to one of the partitions, which in turn is electrically connected to the other partitions, for example by way of being pressed together, by welding, or by brazing. The first fluid and the second fluid may be liquids. The assembly allows for the prevention of growth of microorganisms on the one or more partitions. The electrical power source may be configured to supply an electric current or electric potential for reducing, inhibiting, or preventing growth of microorganisms in the heat exchanger, or on the one or more partitions of the heat exchanger. In extension, the assembly allows for a reduction of the generation or growth of a biofilm on the one or more partitions. Microorganisms are here understood to encompass unicellular organisms that may exist in single-celled forms or in colonies o