A CLEANING IN PLACE UNIT, A CLEANING IN PLACE SYSTEM AND A METHOD THEREOF

Abstract

A cleaning in place, CIP, unit is provided for cleaning a liquid food processing plant by means of a cleaning liquid. The CIP unit comprising: one or more control valves configured to control a liquid flow of the cleaning liquid in the CIP unit; a flow rate arrangement; a balance tank; and a heat exchanger; forming a main circuit with the liquid food processing plant. The CIP unit further comprises a high pressure circuit section configured to bypass the balance tank, the high pressure circuit section comprising: a further control valve; and a pressure arrangement configured to increase the pressure of the cleaning liquid above an atmospheric pressure, wherein the high pressure circuit section is connected to the main circuit thereby forming a high pressure circuit with the main circuit while the high pressure circuit section bypasses the balance tank. A system for cleaning the liquid food processing plant is also provided. A method for cleaning the liquid food processing plant is also provided.

Claims

1. A cleaning in place, CIP, unit for cleaning a liquid food processing plant by means of a cleaning liquid, the CIP unit comprising: a flow rate arrangement configured to control a flow rate of the cleaning liquid; a balance tank configured to balance a volume of the cleaning liquid at an atmospheric pressure; and a heat exchanger configured to transfer heat to and/or from the cleaning liquid; wherein the one or more control valves, the flow rate arrangement, the balance tank and the heat exchanger are connected in series thereby forming a main circuit section, the main circuit section being configured to be connected to the liquid food processing plant thereby forming a main circuit with the liquid food processing plant, wherein the CIP unit further comprises a high pressure circuit section configured to bypass the balance tank, the high pressure circuit section comprising: a further control valve configured to control the liquid flow of the cleaning liquid to bypass the balance tank, and a pressure arrangement configured to control a pressure of the cleaning liquid, wherein the pressure arrangement is configured to increase the pressure of the cleaning liquid above atmospheric pressure, when the cleaning liquid is bypassing the balance tank, wherein the high pressure circuit section is connected to the main circuit thereby forming a high pressure circuit with the main circuit while the high pressure circuit section bypasses the balance tank.

2. The CIP unit according to claim 1, wherein the pressure arrangement configured to control the pressure of the cleaning liquid comprises a pressure pump and a pressure detector, wherein the pressure detector is configured to control an operation of the pressure pump.

3. The CIP unit according to claim 1, further comprises a heating medium inlet configured to provide a heating medium of the heat exchanger, wherein the heat exchanger is configured to increase the temperature of the cleaning liquid above a boiling point of the cleaning liquid at the atmospheric pressure, when the cleaning liquid is fed in the high pressure circuit.

4. The CIP unit according to claim 3, wherein the heating medium provided to the heat exchanger has a temperature of 130-170 C., preferably 140-160 C., more preferably 150 C.

5. The CIP unit according to claim 1, wherein the cleaning liquid has a cleaning temperature of 120-160 C., preferably 130-150 C., more preferably 135-145 C., when the cleaning liquid is fed in the high pressure circuit.

6. The CIP unit according to claim 1, further comprises a cooling medium inlet configured to provide a cooling medium of the heat exchanger, wherein the heat exchanger is configured to decrease the temperature of the cleaning liquid below the boiling point of the cleaning liquid at the atmospheric pressure.

7. The CIP unit according to claim 6, wherein the cooling medium provided to the heat exchanger has a temperature of 70-100 C., preferably 80-100 C., more preferably 95 C.

8. The CIP unit according to claim 1, wherein the flow rate arrangement configured to control the flow rate of the cleaning liquid comprises a flow rate pump and a flow rate detector, wherein the flow rate detector is configured to control an operation of the flow rate pump.

9. The CIP unit according to claim 1, further comprises a control unit configured to control one or more of the one or more control valves, the flow rate arrangement, the balance tank, the heat exchanger, the further control valve and the pressure arrangement.

10. The CIP unit according to claim 1, wherein the CIP unit further comprises at least one cleaning agent inlet and at least one cleaning agent outlet being connected to the main circuit section and being configured to be connected to one or more cleaning agent tanks configured to provide a cleaning agent to the cleaning liquid.

11. The CIP unit according to claim 1, wherein the CIP unit further comprises at least one waste valve being connected to the main circuit section and being configured to discharge the cleaning liquid from the main circuit section.

12. The CIP unit according to claim 1, wherein the CIP unit further comprises a fresh water valve being connected to the balance tank and being configured to feed fresh water to the balance tank.

13. A cleaning in place, CIP, system configured to clean a liquid food processing plant, the CIP system comprising a CIP unit according to claim 1 and the liquid food processing plant connected to the CIP unit.

14. A method for cleaning a liquid food processing plant, the method comprising: connecting a CIP unit according to claim 1 to the liquid food processing plant thereby forming the main circuit, wherein the CIP unit comprises a pressure pump and a pressure detector forming the pressure arrangement of the CIP unit; actuating the further control valve such that the high pressure circuit section bypasses the balance tank thereby forming the high pressure circuit; controlling the pressure pump by means of the pressure detector such that the pressure of the cleaning liquid is increased above the atmospheric pressure, while circulating the cleaning liquid in the high pressure circuit; feeding a heating medium to the heat exchanger, wherein the heat exchanger is configured to transfer heat from the heating medium to the cleaning liquid such that the temperature of the cleaning liquid is increased above a boiling point of the cleaning liquid at the atmospheric pressure; and feeding the cleaning liquid to the liquid food processing plant thereby cleaning the liquid food processing plant.

15. The method according to claim 14 further comprises: subsequent to cleaning the liquid food processing plant, feeding a cooling medium to the heat exchanger, wherein the heat exchanger is configured to transfer heat from the cleaning liquid such that the temperature of the cleaning liquid is decreased below the boiling point of the cleaning liquid at the atmospheric pressure; and when the temperature of the cleaning liquid is below the boiling point of the cleaning liquid at the atmospheric pressure, actuating the further control valve such that the high pressure circuit section is disconnected and the cleaning liquid is fed via the balance tank in the main circuit.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Embodiments will now be described, by way of example, with reference to the accompanying schematic drawings, in which

[0043] FIG. 1 schematically illustrates a cleaning in place, CIP, unit for cleaning a liquid food processing plant, wherein a cleaning liquid of the CIP unit is fed in a main circuit. FIG. 2 schematically illustrates a cleaning in place, CIP, unit for cleaning a liquid food processing plant, wherein a cleaning liquid of the CIP unit is fed in a high pressure circuit.

[0044] FIG. 3 is a flowchart illustrating the steps of a method for cleaning a liquid food processing plant.

DETAILED DESCRIPTION

[0045] With reference to FIG. 1, a cleaning in place, CIP, unit 100 for cleaning a liquid food processing plant (not illustrated) is schematically illustrated by way of example.

[0046] The CIP unit 100 and the liquid food processing plant forming a CIP system. The CIP unit 100 comprises a connecting inlet 128 and a connecting outlet 129. The connecting inlet and outlet 128, 129 are configured to be connected to the liquid food processing plant thereby the CIP unit 100 is connected to the liquid food processing plant. When the CIP unit 100 and the liquid food processing plant are connected, the cleaning liquid may be circulated between the two thereby cleaning the liquid food processing plant. When the cleaning liquid is circulated, the cleaning liquid is received by the CIP unit 100 from the liquid food processing plant via the connecting inlet 128 and the cleaning liquid is discharged from the CIP unit 100 to the liquid food processing plant via the connecting outlet 129. The cleaning liquid is circulated one or more times through the liquid food processing plant in order to obtain a satisfactory cleaning result. The cleaning liquid typically comprises water and/or one or more cleaning agents.

[0047] Before a cleaning process is started, the cleaning liquid is provided to the CIP unit 100 via one or more inlets. The cleaning liquid provided to the CIP unit 100 may be a mixture of the water and the cleaning agent. The water and the cleaning agent may be individually provided to the CIP unit 100 such that the water and the cleaning agent is mixed in the CIP unit 100. As illustrated in FIG. 1, the CIP unit 100 comprises one cleaning agent inlet 130 and one cleaning agent outlet 131. The cleaning agent inlet 130 is configured to feed water and/or cleaning agent from a cleaning agent tank (not illustrated) to the CIP unit 100. Thus, the cleaning agent tank may comprise the cleaning agent or the mixture of the cleaning agent and the water forming the cleaning liquid. The cleaning agent outlet 131 is configured to discharge cleaning liquid from the CIP unit 100. The cleaning liquid may be discharged to the cleaning agent tank. The cleaning liquid may be discharged to a drain (not illustrated). The CIP unit 100 may comprise more than one cleaning agent inlet 130 and more than one cleaning agent outlet 131 to advantage.

[0048] As further illustrated in FIG. 1, the cleaning liquid is feed in a counterclockwise direction in a main circuit section 110 of the CIP unit 100.

[0049] Starting from the connecting inlet 128, the cleaning liquid is thereafter passing a pressure detector (it is a transmitter for this detailed description) 145 and a first waste valve 122a before passing the cleaning agent inlet 130 and cleaning agent outlet 131. The pressure transmitter 145 is discussed in more detail further below. The first waste valve 122a is connected to a drain 123a and may be configured to direct the cleaning liquid to the drain 123a. The drain 123a may be connected to a sewer.

[0050] Thereafter, the cleaning liquid is fed via a further control valve 141 being configured to control the liquid flow of the cleaning liquid. The further control valve 141 is configured to direct the cleaning liquid either in the main circuit section 110 or in a high pressure circuit section 140. The high pressure circuit section 140 is illustrated by a dashed line and will be further discussed in connection with FIG. 2. If the cleaning liquid is directed in the main circuit section 110, the cleaning liquid is fed towards a control valve 111a. The control valve 111a is configured to control the flow of the cleaning liquid and to direct the cleaning liquid to a balance tank 112. The balance tank 112 is configured to balance a volume of the cleaning liquid at an atmospheric pressure. The CIP unit 100 further comprises a fresh water inlet 119 being configured to feed fresh water to the balance tank 112 via a fresh water valve 120c. The fresh water valve 120c is configured to control a water flow of the fresh water inlet thereby controlling the fresh water being fed to the balance tank 112. Thus, the balance tank 112 is further configured to mix fresh water with the cleaning liquid which is fed in the main circuit section 110 via the balance tank 112 such that a predetermined mixture of cleaning liquid and fresh water may be provided. The cleaning liquid is fed from the balance tank 112 towards a pressure pump 144 which will be discussed in more detail in connection with FIG. 2.

[0051] The cleaning liquid is fed from the pressure pump 144 to a flow rate pump 114. The flow rate pump 114 is configured to be controlled by a flow rate detector (it is a transmitter for this detailed description) 115. In particular, the flow rate transmitter 115 is configured to control an operation of the flow rate pump 114. The flow rate pump 114 and the flow rate transmitter 115 forming a flow rate arrangement 150 being configured to control a flow rate of the cleaning liquid. In FIG. 1, the relation or connection between the flow rate transmitter 115 and the flow rate pump 114 is illustrated by a dotted line 116.

[0052] Thereafter, the cleaning liquid is fed to a heat exchanger 113. The heat exchanger 113 is configured to transfer heat to and/or from the cleaning liquid, when the cleaning liquid is fed through the heat exchanger 113. The heat exchanger 113 comprises a cleaning liquid inlet 113a and a cleaning liquid outlet 113b, wherein the temperature of the cleaning liquid is different at the cleaning liquid inlet 113a and the cleaning liquid outlet 113b. The heat exchanger 113 further comprises a heating/cooling medium inlet 113c and a heating/cooling medium outlet 113d, wherein a temperature of the heating/cooling medium is different at the heating/cooling medium inlet 113c and the heating/cooling medium outlet 113d. The heating/cooling medium inlet 113c is configured to feed heating/cooling medium to the heat exchanger 113, wherein the heating/cooling medium is configured to transfer heat to and/or from the heating/cooling medium from and/or to the cleaning liquid.

[0053] The CIP unit 100 further comprises a heating medium inlet 117 configured to provide the heating medium (It is steam for this detailed description) to the CIP unit 100. The steam is fed via a control valve 111b and a temperature regulating valve 124 to the heating/cooling medium inlet 113c of the heat exchanger 113. The steam is configured to be used as heating medium in the heat exchanger 113 when the heat exchanger 113 is configured to transfer heat to the cleaning liquid. Thereby, the temperature of the cleaning liquid is increased. The control valve 111b is configured to control a steam flow of the steam such that a desired amount of steam is fed to the heat exchanger 113. The steam preferably has a steam temperature of 150 C. when entering the heat exchanger 113. Other temperatures such as 130-170 C., preferably 140-160 C., may be used to advantage. The cleaning liquid preferably has a cleaning temperature of 135-145 C. when entering the liquid food processing plant. Other temperatures such as 120-160 C., preferably 130-150 C., may be used to advantage.

[0054] The CIP unit 100 further comprises a cooling medium inlet (the cooling medium is water in this detailed description) 118 configured to provide water to the CIP unit 100. The water is fed via the control valve 111b and the temperature regulating valve 124 to the heating/cooling medium inlet 113c of the heat exchanger 113. The water is configured to be used as cooling medium in the heat exchanger 113 when the heat exchanger 113 is configured to transfer heat from the cleaning liquid. Thereby, the temperature of the cleaning liquid is decreased. The control valve 111b is configured to control a water flow of the water such that a desired amount of water is fed to the heat exchanger 113. The water preferably has a water temperature of 95 C. when entering the heat exchanger 113. Other temperatures such as 70-100 C., preferably 80-100 C., may be used to advantage.

[0055] The control valve 111b is configured to control that either steam or water is fed to the heat exchanger 113.

[0056] The temperature regulating valve 124 is controlled by a temperature detector (it is a transmitter for this detailed description) 125. The temperature regulating valve 124 and the temperature transmitter 125 forming a temperature arrangement 160 being configured to control the temperature of the steam or water fed to the heat exchanger 113. In FIGS. 1 and 2, the relation or connection between the temperature transmitter 125 and the temperature regulating valve 124 is illustrated by a dotted line 126.

[0057] The cleaning liquid outlet is connected to a valve 127. The valve 127 is configured to direct the cleaning liquid towards the connecting outlet 129. The cleaning liquid is passing the flow rate transmitter 115 before entering the liquid food processing plant via the connecting outlet 129.

[0058] The heating/cooling medium outlet is connected to a regulating valve 121. The regulating valve 121 is configured to direct the heating/cooling medium discharged from the heat exchanger 113 to either a first drain 123c or a second drain 123b. The second drain 123b is controlled by a waste valve 122b.

[0059] The control valve 111a, the flow rate arrangement, the balance tank 112, and the heat exchanger 113 are connected in series thereby forming the main circuit section 110. As said above, the main circuit section 110 is configured to be connected to the liquid food processing plant thereby forming a main circuit with the liquid food processing plant.

[0060] The CIP unit 100 further comprises a control unit 133. The control unit 133 is configured to control the operation of the components comprised in the CIP unit.

[0061] With reference to FIG. 2, the further control valve 141, as introduced above, is directing the cleaning liquid in the high pressure circuit section 140 instead of in the main circuit section 110. The control valve 141 is configured to control the liquid flow of the cleaning liquid to bypass the balance tank 112. This is illustrated by the dashed line between the further control valve 141 and the pressure pump 144, via the balance tank 112. Instead, the cleaning liquid is fed directly to the pressure pump 144. In this way, the high pressure circuit section 140 is connected to the main circuit thereby forming a high pressure circuit with the main circuit while the high pressure circuit section 140 bypasses the balance tank 112. When the high pressure circuit section 141 is bypassing the balance tank 112, the CIP unit 100 forms a closed loop or circuit with the liquid food processing plant, if the liquid food processing plant is a closed equipment as discussed above. The pressure transmitter 145 is configured to control the operation of the pressure pump 144. The pressure pump 144 is controlled by means of the pressure transmitter 145 such that the pressure of the cleaning liquid is increased above the atmospheric pressure. The pressure pump 144 and the pressure transmitter 145 forming a pressure arrangement 170 being configured to control a pressure of the cleaning liquid. In FIGS. 1 and 2, the relation or connection between the pressure transmitter 145 and the pressure pump 144 is illustrated by a dotted line 146. When the pressure of the cleaning liquid is increased above the atmospheric pressure, the boiling point of the cleaning liquid is increased above the boiling point of the cleaning liquid at the atmospheric pressure. Thereby, the heat exchanger 113 is configured to transfer heat to the cleaning liquid, using the steam as the heating medium, such that the temperature of the cleaning liquid is increased above the boiling point of the cleaning liquid at the atmospheric pressure.

[0062] Before the further control valve 141 is configured to control the liquid flow of the cleaning liquid to be fed via the balance tank 112, i.e. after cleaning of the liquid food processing plant has been conducted, the heat exchanger 113 is configured to decrease the temperature of the cleaning liquid below the boiling point of the cleaning liquid at atmospheric pressure as discussed in connection with FIG. 1.

[0063] Although not illustrated, the high pressure circuit section 140 may be connected to the main circuit before the pressure pump 144.

[0064] Apart from that the further control valve 141 is directing the liquid flow in the high pressure circuit section 140, the CIP unit illustrated in FIG. 2 comprises the same features as discussed in connection with FIG. 1.

[0065] With reference to FIG. 3, is a flowchart illustrating a method 300 for cleaning the liquid food processing plant. The method comprises a first step S302 in which the CIP unit 100 as discussed in connection with FIG. 1 is connected to the liquid food processing plant thereby the main circuit is formed. Thereafter, in a second step S304, the further control valve 141 being actuated such that the high pressure circuit section 140 bypasses the balance tank 112. Thereby the high pressure circuit is formed. In a third step S306, the pressure pump 144 is controlled by means of the pressure transmitter 145 such that the pressure of the cleaning liquid is increased above the atmospheric pressure, while circulating the cleaning liquid in the high pressure circuit. Thereafter, in a fourth step S308, the steam is fed to the heat exchanger 113. The heat exchanger 113 is configured to transfer heat from the steam to the cleaning liquid such that the temperature of the cleaning liquid is increased above the boiling point of the cleaning liquid at the atmospheric pressure. In a fifth step S310, the cleaning liquid is fed to the liquid food processing plant thereby cleaning the liquid food processing plant.

[0066] Optionally, in a sixth step S312, subsequent to cleaning the liquid food processing plant, the water is fed to the heat exchanger 113, wherein the heat exchanger 113 is configured to transfer heat from the cleaning liquid such that the temperature of the cleaning liquid is decreased below the boiling point of the cleaning liquid at the atmospheric pressure. In a seven step S314, when the temperature of the cleaning liquid is below the boiling point of the cleaning liquid at the atmospheric pressure, the further control valve 141 being actuated such that the high pressure circuit section 141 is disconnected and the cleaning liquid is fed via the balance tank 112 in the main circuit.

[0067] Even though illustrated and described in a certain order, other orders may also be used.

[0068] From the description above follows that, although various embodiments of the invention have been described and shown, the invention is not restricted thereto, but may also be embodied in other ways within the scope of the subject-matter defined in the following claims.