Patent Application
20240166540
The present invention relates to a method for treating industrial process fluids, a fluid treatment system for treating industrial process fluids and a system using an industrial process fluid and comprising a fluid treatment system.
Industrial process fluids, such as for example metal working fluids and washing fluids which are used in industrial processes, where metal working fluids can comprise for example cutting fluids, washing fluids and quenching fluids, need to be treated regularly when used in a system. For example, an industrial process fluid concentrate may need to be added to compensate for pull-out (consumption) and water may need to be added to compensate for evaporation that may occur during use of the industrial process fluid in the system. Further treatment of the industrial process fluid may also be needed from time to time such as a purification treatment.
For measuring a concentration of an industrial process fluid concentrate in an industrial process fluid some kind of sensor is needed. For example, a refractometer may be used which optically measures the fluids refractive index. There are problems related to using sensors in industrial process fluids. Any sensor that is continuously in contact with the industrial process fluid will usually get contaminated due to the fact that industrial process fluids may be heavily contaminated, which often is the case in for example both metal working fluids and washing fluids. The contamination may cause the sensor to show an incorrect value. The sensors may need to be cleaned and calibrated from time to time to work correctly.
An object of the invention is to provide an improved method and system for treating industrial process fluids.
A further object of the invention is to provide an improved method and system for controlling a concentration of an industrial process fluid concentrate in an industrial process fluid.
This is achieved in a method, a fluid treatment system and a system using industrial process fluid according to the independent claims.
According to one aspect of the invention a method for treating an industrial process fluid used in a system is provided. Said method comprises the steps of:
According to another aspect of the invention a fluid treatment system for treating an industrial process fluid used in a system to which the fluid treatment system can be connected is provided. Said fluid treatment system comprises:
According to another aspect of the invention a system using industrial process fluid is provided, wherein said system comprises a fluid treatment system as defined above, wherein said fluid treatment system is connected to an outlet and an inlet provided in the system.
Hereby, by providing the sensor device in a fluid path external to the system where the industrial process fluid is used, the sensor device need not be immersed in industrial process fluid all the time and can hereby be kept clean and less affected by the industrial process fluid and hereby give correct measuring results for a longer time compared to if the sensor device was positioned in industrial process fluid all the time. Furthermore, according to the invention a step of adding new industrial process fluid concentrate in dependence of the measured concentration is provided and this addition of concentrate is according to the invention provided via the sensor device. Hereby the sensor device will be immersed in clean industrial process fluid concentrate regularly which will serve as a cleaning of the sensor. Hereby, there is no need for a stop in the process for the cleaning of the sensor. Hereby an effective and reliable method and system is achieved for treating industrial process fluid where a sensor device can be used reliably for a long time and provide correct sensor output.
One or more valves provided in the system needs to be controlled by a control system for transferring industrial process fluid concentrate into the sensor device and for keeping the industrial process fluid concentrate in the sensor device for a certain time period for performing the cleaning. By keeping the sensor device immersed in industrial process fluid concentrate for a certain time period the sensor device will be effectively cleaned.
In some embodiments of the invention said sensor device comprises a refractometer. Also other sensors can be provided in the sensor device such as a pH sensor and/or a conductivity sensor.
In some embodiments of the invention the step of transferring a part of an industrial process fluid provided in the system through a first fluid path arrangement of a fluid treatment system comprises dividing a flow of the industrial process fluid when passing through the first fluid path arrangement of the fluid treatment system into at least a main fluid path and a return loop fluid path, wherein said main fluid path comprises a first pump and said return loop fluid path either comprises the sensor device or is connected to a possible separate sensor device fluid path of the first fluid path arrangement, wherein said sensor device fluid path comprises the sensor device, wherein said return loop fluid path is connected to the main fluid path such that a part of the fluid flow in the main fluid path can be returned over the first pump via the return loop fluid path and wherein a fluid flow through said return loop fluid path is driven by a differential pressure over the first pump. Hereby a large mixing flow can be provided through the main fluid path all the time or often and a fluid flow through the sensor device is only needed occasionally, for measuring a concentration of the industrial process fluid concentrate in the industrial process fluid and for addition of industrial process fluid concentrate and possibly for addition of water. Hereby the sensor device and other sensitive components such as the valves will not be exposed to the harsh industrial process fluid more than necessary and this will prolong their lifetime and reliability. Furthermore, a good mixing of industrial process fluid can still be performed in the fluid treatment system at all time via the main fluid path and the first pump.
In some embodiments of the invention the step of measuring a concentration of an industrial process fluid concentrate in the industrial process fluid and the step of adding an amount of this industrial process fluid concentrate to the industrial process fluid used in the system comprises sucking industrial process fluid and industrial process fluid concentrate respectively through the sensor device by an ejector pump which is driven by the first pump in the main fluid path and connected to an outlet of the sensor device. By using an ejector pump no further pump is needed in the system, i.e. no separate pump is needed for pumping the industrial process fluid concentrate from the industrial process fluid concentrate tank. This is suitable because the industrial process fluid concentrate may have high viscosity and a chemically aggressive nature that may damage other types of pumps. An ejector pump on the other hand is not that sensitive. Also an ejector pump can handle unlimited dry running without taking damage. This may occur when the industrial process fluid concentrate tank is empty. The ejector pump does not require a separate power supply since it is driven by the first pump which is suitable. This is suitable for the cleaning process of the sensor device and is described in more detail in the detailed description.
In some embodiments of the invention the method further comprises the step of adding water to the industrial process fluid in the system, whereby the adding of water is provided via the sensor device. Hereby the sensor device can be stored in water between uses which is suitable for preserving of sensor functions and prolong a lifetime of the sensor device. Furthermore, the sensor device can be calibrated by use of the water at certain time intervals by use of the water passing the sensor device on its way into the system.
In some embodiments of the invention the method comprises mixing the industrial process fluid used in the system by pumping the industrial process fluid via the fluid treatment system. Furthermore, the added industrial process fluid concentrate can be effectively mixed into the industrial process fluid in the main fluid path and in the first pump. This is important for effective use of the industrial process fluid in the system.
In some embodiments of the invention the method further comprises the step of irradiating the industrial process fluid by UV light in a UV reactor provided in the fluid treatment system, whereby the method further comprises the step of pumping the industrial process fluid through the reactor by the first pump. Hereby the industrial process fluid can also be treated by UV and bacteria can be destroyed. Bacteria in an industrial process fluid can be problematic in many applications. In the embodiments of the invention where a UV reactor is provided the pump used for pumping the industrial process fluid through the UV reactor is also used for mixing of the industrial process fluid concentrate into the industrial process fluid. Hereby a combined effect is provided where both mixing, addition of industrial process fluid concentrate and UV treatment is performed effectively.
In some embodiments of the invention said industrial process fluid is a metal working fluid. The industrial process fluid may also be for example a washing fluid.
Further embodiments of the invention are described in the detailed description and in the dependent claims.
The present invention relates to the treatment of industrial process fluids. Industrial process fluids can be for example metal working fluids or washing fluids which are used in industrial processes. Washing fluids may be used in different stages of many different industrial processes such as for example washing of materials or components or washing of manufacturing equipment. Metal working fluids can comprise for example cutting fluids, washing fluids and quenching fluids which are used in metal working industry. The present invention may be especially effective for treating industrial process fluids comprising an oil emulsion. Measuring concentrations in oil emulsions can be problematic due to the way refractometers interact with the droplet sizes in emulsions. Measuring emulsions correctly requires the sensor to be very clean. Hereby the present invention can be especially suitable for these types of industrial process fluids which will be discussed in more detail below. Said industrial process fluids are used in different types of systems. Often said systems comprise an industrial process fluid tank where the industrial process fluid is collected. The industrial process fluid needs to be treated at regular time intervals. For example, an industrial process fluid concentrate may need to be added if a concentration of the industrial process fluid concentrate in the industrial process fluid has decreased during use of the industrial process fluid in the system. Furthermore, water may need to be added because of vaporisation of water from the industrial process fluid during use in the system and still further it may be necessary to purify the industrial process fluid from bacteria, particles or other contaminants.
According to the present invention a method for treating industrial process fluids and a fluid treatment system for treating industrial process fluids used in a system are provided. The method and the fluid treatment system are described together with reference to the different embodiments of the fluid treatment system which are shown in
According to the invention a fluid treatment system 100; 100′; 200; 200′; 300; 300′; 400; 400′; 500; 500′; 600; 700; 800; 800′ for treating an industrial process fluid used in a system 8 to which the fluid treatment system can be connected is provided. The system can for example be any type of machine or other industrial equipment that uses industrial process fluid. The system 8 comprises often an industrial process fluid tank 11 which is a tank where the industrial process fluid is collected when it is not in use in the system. The fluid treatment system 100; 100′; 200; 200′; 300; 300′; 400; 400′; 500; 500′; 600; 700; 800; 800′ according to the invention is configured to be connected to such a system 8 which is using industrial process fluid. If an industrial process fluid tank 11 is provided in the system 8 the fluid treatment system can be connected to the industrial process fluid tank 11 but it can also be connected at other positions in the system. The fluid treatment system comprises hereby a first fluid connector 3a configured to be connected to an outlet 13a provided in the system 8. The outlet 13a can for example be provided in an industrial process fluid tank 11 of the system 8. The first fluid connector 3a is configured for receiving industrial process fluid into the fluid treatment system. The fluid treatment system comprises further a second fluid connector 3b configured to be connected to an inlet 13b provided in the system 8 for returning industrial process fluid after treatment in the fluid treatment system. The inlet 13b can for example be provided in an industrial process fluid tank 11 of the system 8. The fluid treatment system comprises furthermore a first fluid path arrangement 21 which is fluidly connecting the first fluid connector 3a and the second fluid connector 3b. The first fluid path arrangement 21 comprises a first pump 23 configured to pump industrial process fluid from the first fluid connector 3a to the second fluid connector 3b and a sensor device 25 which is connected in the first fluid path arrangement 21 such that it receives at least a part of the industrial process fluid pumped by the first pump 23, wherein said sensor device 25 is configured for measuring a concentration of an industrial process fluid concentrate in the industrial process fluid. The industrial process fluid concentrate can for example be a metal working fluid concentrate in the example of metal working fluid as industrial process fluid or a washing fluid concentrate in the example of a washing fluid as the industrial process fluid. The sensor device comprises for example a refractometer which is a sensor which measures a refractive index of a fluid and can for example be used for measuring a concentration of a content in a fluid. The sensor device 25 can also in some embodiments of the invention comprise other types of sensors, such as a pH sensor and/or a conductivity sensor.
The fluid treatment system comprises furthermore a second fluid path arrangement 31 which is provided in connection with an inlet 25a of the sensor device 25. The second fluid path arrangement 31 comprises a third fluid connector 3c configured to be connected to an industrial process fluid concentrate tank 22. The second fluid path arrangement 31 comprises also in some embodiments a valve, here called a concentrate valve 27a.
With this fluid treatment system 100; 100′; 200; 200′; 300; 300′; 400; 400′; 500; 500′; 600; 700; 800; 800′ an industrial process fluid concentrate can be provided by the fluid treatment system from a connected industrial process fluid concentrate tank 22, first via the second fluid path arrangement 31 and then via the sensor device 25 in the first fluid path arrangement 21 and further via the first fluid path arrangement 21 to the second fluid connector 3b for further being transferred into a connected system 8. By providing industrial process fluid concentrate to the system 8 via the sensor device 25 the sensor device will be regularly immersed in clean industrial process fluid concentrate which is suitable because it serves as a cleaning of the sensor device 25. Furthermore, by positioning the sensor device 25 in an external fluid path outside the system 8 the sensor device 25 will not be immersed in the industrial process fluid all the time which will prolong a lifetime for the sensor device because the industrial process fluid is often very contaminated and harsh for the sensor device. Contaminants can attach to the sensor device, for example a refractometer, and disturb refractive reading. Hereby measurement reliability and a sensor lifetime can be improved by this invention. Even further the sensor device 25 itself can be used as an indicator for the presence of an industrial process fluid concentrate in the industrial process fluid concentrate tank 22. A reading from the sensor device 25 can indicate if the flow of industrial process fluid concentrate has stopped due to the industrial process fluid concentrate tank 22 being empty. And even further the added industrial process fluid concentrate can be effectively mixed into the industrial process fluid in the first fluid path arrangement 21 of the fluid treatment system. The industrial process fluid concentrate and the circulated industrial process fluid from the system 8 will be effectively mixed in the first pump 23 and possibly no other mixing device needs to be provided to for example an industrial process fluid tank 11 of the system 8 for mixing of the industrial process fluid.
With reference to all the drawings and specifically to
S1: Transferring a part of an industrial process fluid used in the system 8 through a first fluid path arrangement 21 of a fluid treatment system 100; 100′; 200; 200′; 300; 300′; 400; 400′; 500; 500′; 600; 700; 800; 800′ connected to an outlet 13a and an inlet 13b of the system 8. The industrial process fluid will be circulated through the first fluid path arrangement 21 of the fluid treatment system and received into the fluid treatment system from the outlet 13a of the system 8 (possibly provided in an industrial process fluid tank 11 of the system 8) and returned to the system 8 (possibly an industrial process fluid tank 11 of the system 8) via the inlet 13b.
S2: Measuring a concentration of an industrial process fluid concentrate in the industrial process fluid by a sensor device 25 provided in the first fluid path arrangement 21 of the fluid treatment system 100; 100′; 200; 200′; 300; 300′; 400; 400′; 500; 500′; 600; 700; 800; 800′.
S3: Adding an amount of this industrial process fluid concentrate to the industrial process fluid used in the system 8 in order to maintain a predefined concentration level, wherein said amount is calculated partly based on the measured concentration, whereby the industrial process fluid concentrate is provided into the system 8 via the sensor device 25 in the fluid treatment system.
The amount of industrial process fluid concentrate to add is calculated based on also other factors such as a total volume of industrial process fluid in the system 8. An amount of added industrial process fluid concentrate can in some embodiments of the invention be controlled by use of a flow sensor measuring the flow of an industrial process fluid concentrate into the fluid treatment system and in other embodiments of the invention a time period for opening a valve and allowing an industrial process fluid concentrate from an industrial process fluid concentrate tank 22 to pass into the fluid treatment system can be calculated based on a pump effect and a viscosity of the industrial process fluid concentrate.
In some embodiments of the invention the method further comprises a step of:
S4: Cleaning the sensor device 25 at certain time intervals by providing the industrial process fluid concentrate into the sensor device 25 and keeping the industrial process fluid concentrate in the sensor device for a certain time period. The industrial process fluid concentrate will have a cleaning effect on the sensor device which can be utilised in this method and system according to the invention where the industrial process fluid concentrate is added via the sensor device and then into the system 8.
In some embodiments of the invention, which will be described in further detail below with reference to
In some embodiments of the invention the method further comprises the step of:
S5: Adding water to the industrial process fluid in the system 8, whereby the adding of water is provided via the sensor device 25. Fluid treatment systems 100′, 200′, 300′, 400′, 500′, 600, 700, 800′ which are adapted for water addition are shown in
S6: Calibrating the sensor device at certain time intervals by use of the water passing the sensor device on its way into the industrial process fluid tank.
In these fluid treatment systems 100′, 200′, 300′, 400′, 500′, 600, 700, 800′ according to the invention where water can be added via the sensor device 25, the sensor device 25 can also be stored in water between the measurements. This is suitable because water will not affect the sensor device negatively and the sensor device will be usable for a longer time. A further advantage with providing water and industrial process fluid concentrate into the system 8 via the sensor device 25 is that the sensor device 25 can be used for registering an outage of industrial process fluid concentrate or water or a stop in the system. The output from the sensor device 25 will clearly indicate if there is water, industrial process fluid or industrial process fluid concentrate in the sensor device 25 and hereby a non-expected output from the sensor device would indicate a stop in the system or that there is no industrial process fluid concentrate left in the industrial process fluid concentrate tank 22. Hereby a user of the system can get an alert when the industrial process fluid concentrate tank 22 is empty and/or when there is a stop in the water supply.
In some embodiments of the invention the method further comprises the step of:
S7: Irradiating the industrial process fluid by UV light in a UV reactor 61 which in some embodiments of the invention is provided in the fluid treatment system 500; 500′; 600; 700; 800;800′. Such fluid treatment systems which comprise a UV reactor 61 are shown in
The different embodiments as shown in
The first fluid path arrangement 21 comprises furthermore a sensor device 25 which in this embodiment is connected in the first fluid path arrangement 21 such that the industrial process fluid pumped by the first pump 23 will pass the sensor device 25. The sensor device 25 is configured for measuring a concentration of an industrial process fluid concentrate in the industrial process fluid.
The fluid treatment system 100 comprises furthermore a second fluid path arrangement 31 which is provided in connection with an inlet 25a of the sensor device 25, wherein said second fluid path arrangement 31 comprises a third fluid connector 3c configured to be connected to an industrial process fluid concentrate tank 22. The second fluid path arrangement 31 comprises also in some embodiments a valve, here called a concentrate valve 27a. Hereby the fluid treatment system 100 can be connected to an industrial process fluid concentrate tank 22 and industrial process fluid concentrate can be provided via the fluid treatment system 100 to the system 8. This description of the second fluid path arrangement 31 is also common for most embodiments and will not be repeated again for all the embodiments.
In this embodiment of the invention, but not in all embodiments, the second fluid path arrangement 31 further comprises a concentrate pump 24. The first fluid path arrangement 21 comprises furthermore in this embodiment but not in all embodiments, a valve 27′. By controlling the concentrate valve 27a, the valve 27′, the first pump 23 and the concentrate pump 24 in the fluid treatment system 100 the addition of industrial process fluid concentrate from the industrial process fluid concentrate tank 22 can be controlled. This addition should be based on a concentration measurement by the sensor device 25 as discussed above. In some embodiments of the invention the fluid treatment system 100 further comprises a control system 60. In
The third fluid path arrangement 41 comprises suitably, but not necessarily some more components. One or more of the components described in this passage may be provided in a third fluid path arrangement 41 according to the invention. A dirt filter 43 for filtering other possible content than water from the water supply may be provided. A constant flow valve 45 which will assure a certain flow of water into the fluid treatment system 100′ may be provided and a non return valve 47 which will ensure that no fluid is flowing out from the fluid treatment system 100′ via the third fluid path arrangement 41 may be provided. These parts of the third fluid path arrangement 41 are the same for all the embodiments which include the third fluid path arrangement 41 and will not be described in detail again.
As partly already described above there are many advantages with a fluid treatment system according to the invention. By moving the sensor device 25 outside the system the sensor device will not be fouled and contaminated by the industrial process fluid as fast as if it was positioned all the time in the industrial process fluid inside for example the industrial process fluid tank 11 of the system 8. Furthermore, by adding new industrial process fluid concentrate into the system 8 via the sensor device, the sensor device 25 can be cleaned regularly in an easy way. Even further the sensor device itself can be used as an indicator if the industrial process fluid concentrate tank 22 is empty of industrial process fluid concentrate. In some embodiments of the invention also water can be added via the sensor device 25 which is suitable because then the sensor device 25 can also easily be calibrated by use of the water and the sensor device can be stored in water as described above.
In the fluid treatment system 200 according to this embodiment a fluid flow can be pumped through the main fluid path 21a by the first pump 23 while both the concentrate valve 27a and the return loop valve 27b are closed. When a concentration of industrial process fluid concentrate should be measured by the sensor device 25 the return loop valve 27b is opened. When the return loop valve 27b is open a part of the fluid flown through the main fluid path 21a will be transferred via the return loop fluid path 21b. The fluid flow through said return loop fluid path 21b is driven by a differential pressure over the first pump 23. If the measured concentration indicates a low level it may be necessary to add industrial process fluid concentrate from the industrial process fluid concentrate tank 22 whereby the concentrate valve 27a is opened and the concentrate pump 24 is turned on. The return loop valve 27b may at the same time be closed but it can also be kept open. Hereby industrial process fluid concentrate is pumped via the second fluid path arrangement 31 from the industrial process fluid concentrate tank 22 to the inlet 25a of the sensor device 25. The industrial process fluid concentrate is transferred through the sensor device 25 and will be mixed with the industrial process fluid flow in the main fluid path 21a of the first fluid path arrangement 21 and in the first pump 23 and be pumped through the first fluid path arrangement 21 and further transferred to the second fluid connection 3b and further into the system 8. The mixing in the first pump 23 with the industrial process fluid in the main fluid path 21a will be very efficient which is suitable. Without a good inmixing of an industrial process fluid concentrate in an industrial process fluid it is a risk that the industrial process fluid concentrate will sink to a bottom and not be properly utilised. A flow through the main fluid path 21a can be relatively large and can also be provided relatively often or all the time or almost all the time independently of the measuring of concentration in the sensor device and the addition of industrial process fluid concentrate. Hereby the fluid treatment device according to the invention can be effectively used for mixing of an industrial process fluid in a system 8, such as mixing of an industrial process fluid in an industrial process fluid tank 11 of a system 8. During cleaning of the sensor device 25 the return loop valve 27b is closed and industrial process fluid concentrate can be kept inside the sensor device 25 and thereby clean the sensor device 25. Hereby the pumps, valves and the sensor device can be controlled to both mix the industrial process fluid in the system 8, measuring the concentration of industrial process fluid concentrate in the industrial process fluid, addition of industrial process fluid concentrate and cleaning of the sensor device.
In
In the embodiment shown in
When industrial process fluid concentrate is added in this embodiment of the invention a very good mixing of the concentrate into the industrial process fluid is provided because it is first mixed in the ejector pump 29 and then also in the first pump 23. Another advantage with this embodiment is that a possible leakage in for example the return loop valve 27b and/or the sensor device fluid path valve 27d is not very critical. This is because the ejector 29 will not work and suck a fluid from the sensor device 25 until a certain flow is provided through the ejector 29. If there is only a small leakage in the return loop valve 27b the suction inlet 29c of the ejector will not be sucking. This is suitable because for example when an industrial process fluid concentrate should be kept in the sensor device 25 for cleaning the sensor device a leakage would be negative. The ejector 29 will act as a barrier between the sensor device 25 and the rest of the fluid treatment system (i.e., the mixing performed in the main fluid path 21a and in the first pump 23). In these embodiments of the invention the sensitive parts of the system, such as the sensor device 25 and to some extent the valves 27a,b,c,d, will be kept outside the main flow of industrial process fluid which is provided in the main fluid path 21a. The sensitive parts will only be exposed to the industrial process fluid during short periods, i.e., only when needed. Hereby a lifetime of the sensitive components will be prolonged.
The fluid treatment system 500 as shown in
The sensor device 25 is in this embodiment connected in a separate sensor device fluid path 21c together with a separate sensor device pump 26.
The sensor device pump 26 can pump a part of the fluid flow from the main fluid path 21a into the separate sensor device fluid path 21c. A second fluid path arrangement 31 is connected to an inlet of the sensor device 25a in the same way as described above in relation to for example
The fluid treatment system 500′ as shown in
The embodiment shown in
By combining the addition of industrial process fluid concentrate with UV treatment of industrial process fluid some important synergies are achieved. By mixing the industrial process fluid concentrate into the industrial process fluid via the first pump 23 the inmixing of the concentrate in the industrial process fluid will be effective. Furthermore, a UV treatment of the industrial process fluid will be more effective if there is a correct concentration of industrial process fluid concentrate in the industrial process fluid. Still further, in many of the embodiments the effect from the first pump 23 which is primarily used for the UV treatment is also used for pumping the industrial process fluid concentrate from the industrial process fluid concentrate tank 22 and for pumping a smaller part of the industrial process fluid flow through a sensor device for measuring the concentration. Hereby a very effective and robust system is achieved. The advantages related to cleaning and calibration of the sensor device have been discussed above. A fluid treatment system according to the invention provides for a very effective and convenient treatment of industrial process fluids.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2150334-7 | Mar 2021 | SE | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/SE2022/050261 | 3/18/2022 | WO |
