NL2022170B1 - Method and device for operating a reverse osmosis (RO) process for treating a process flow - Google Patents

Abstract

The invention relates to a method and device for operating a reverse osmosis (RO) process for treating a process stream. The method according to the invention comprises: supplying a process flow to a treatment device; - treating the process flow in the treatment device; - cleaning and / or stopping the process flow treatment; and - realizing a plug flow for removing an amount of process flow present in the process.

Description

Θ 2022170 © B1 PATENT (2?) Application number: 2022170 (22) Application submitted: 11 December 2018 (51) Int. Cl .:

B01D 61/02 (2019.01) B01D 61/04 (2019.01) B01D

61/12 (2019.01) B01D 61/58 (2019.01) B01D 65/02 (2019.01) (30) Priority:

July 2018 NL 2021235 ^ 7) Application registered:

January 2020 (43) Request published:

(73) Patent holder (s):

Wafilin Systems B.V. in LEEUWARDEN (72) Inventor (s):

Harm Dalfsen in Steenwijk Thomas Roersma in Marrum (74) Agent:

ir. P.J. Hylarides et al. In The Hague

Patent granted:

January 2020

45) Patent issued:

January 2020

54) Method and device for operating a reverse osmosis (RO) process for treating a process stream

57) The invention relates to a method and device for operating a reverse osmosis (RO) process for treating a process stream. The method according to the invention comprises:

- supplying a process flow to a treatment device;

- treating the process flow in the treatment device;

- cleaning and / or stopping the process flow treatment; and

- realizing a plug flow for removing an amount of process flow present in the process.

NLB1 2022170

This patent has been granted regardless of the attached result of the research into the state of the art and written opinion. The patent corresponds to the documents originally submitted.

Method and device for operating a reverse osmosis (RO) process for treating a process stream

The invention relates to a method for operating a reverse osmosis (RO) process for treating a process stream, for example a stream of process water or dairy. More in particular, the invention relates to the cleaning of such a process. From practice it is known to treat a process flow with an RO process. Such processes must be cleaned periodically. Such processes are also sometimes stopped, for example for maintenance, adjustment of process capacity.

A problem that occurs when cleaning or stopping such processes is that the amount of process fluid present in the process must be drained away. In practice, this amount is often discharged to the sewer. This means an additional load for, for example, a treatment plant. Such a cleaning at cessation also leads to loss of components, for example of the proteins present in the process liquid.

The present invention has for its object to eliminate or alleviate the aforementioned problems.

This object is achieved with the method according to the invention for operating a reverse osmosis (RO) process for treating a process flow, the method comprising:

supplying a process flow to a treatment device;

treating the process stream in the treatment device;

cleaning and / or stopping the treatment of the process stream; and realizing a plug flow for removing an amount of process flow present in the process.

In the treatment of process streams, often valuable products are filtered / separated into so-called concentrate and permeate streams. The systems must also be cleaned regularly, whereby sharp separations or barriers are required at the moment of displacing the concentrate. This concentrate stream is often expensive and must be absorbed in order to prevent product loss before cleaning, on the other hand a diluted concentrate stream can lead to extra waste water with associated costs. By removing the amount of process fluid still present in the installation with a plug flow during a cleaning of a treatment device, such as an RO installation, it is possible to make good use of this quantity. This is achieved by, as it were, propelling the relevant amount of process fluid forward by supplying a cleaning fluid or other suitable fluid and thereby avoiding mixing as much as possible. To avoid such a mixing, any recirculation steps in the process are avoided. As a result, the yield of the amount of process fluid still present in the process becomes as large as possible. This limits purification costs by reducing the discharge of process fluid with process substances still present, such as proteins. These substances then do not need to be purified. These process substances are also used meaningfully.

In a presently preferred embodiment according to the invention the process flow / product flow present in the system is flushed out without pumping via a plug flow situation in the process. In a possible embodiment this can be realized effectively by adjusting the pump frequency and opening 2 valves and closing 1.

In a preferred embodiment, currents adjust during flushing / cleaning, whereby a transition is made from a recirculation system in the operating state to a so-called plug flow in the cleaning state. The product in the installation will be completely displaced in just a few minutes to the desired collection tank (s) and can be switched, for example, at the tank level in the water / cleaning tank.

After the product has been displaced, it will be possible for the concentrate discharge to switch to drain / sewer and a little later to return cleaning tank, whereby the permeate flow can be returned at the right moment and therefore a complete circulation of the in and out outgoing flows. Cleaning agent can be added if desired. The desired crossflow lean can therefore be set again, which will have an effect on the cleaning. The rinsing of this cleaning fluid can then also be carried out again in plug flow by switching the supply to the water tank and adjusting the frequencies of the circulation pumps.

The invention can be applied to various process flows. For example, it is possible to use the invention in the treatment of process water from the potato processing industry, as well as in the treatment of a dairy stream. It will be clear that it is also possible to apply the invention to still other process flows.

In an advantageous embodiment according to the invention, the method comprises the step of realizing a plug flow comprising controlling one or more process pumps with switching means.

By realizing a plug flow, the process fluid is propelled forward and executed in the desired manner and can therefore be used effectively. The plug flow is realized by preventing or stopping any recirculation flows or circulation flows. This avoids the aforementioned mixing of process fluid and cleaning fluid. Preferably the amount of valves in the process is minimized. This has the advantage that costs for the installation are minimized. Furthermore, limiting the number of valves reduces the risk of contamination or contamination. In addition, the limitation also increases the reliability of the process.

In an advantageous preferred embodiment according to the invention, several RO (sub) systems are set in series or in parallel, whereby it is possible, for example, to stop and / or clean one (sub) system, while the other (sub) systems can continue to run. As a result, the treatment of the process flow does not have to be stopped, while, for example, cleaning is possible. The process installation is preferably dimensioned such that a (sub) system can be stopped for at least part of the period of operation of the installation without substantially influencing the processing capacity.

The invention also relates to a device for operating a reverse osmosis (RO) process for treating a process stream, the device comprising: a feed for supplying a process stream to be treated; an RO installation adapted to handle the process flow;

an output for discharging the treated process stream; and switching means for switching the device between operating state and a cleaning state in which a plug flow is provided for removing an amount of process flow present in the process.

The device provides similar advantages and / or effects as described for the method.

Further advantages, features and details of the invention are elucidated on the basis of preferred embodiments thereof, wherein reference is made to the accompanying drawings, in which:

Figure 1 is a schematic representation of a process for treating a process stream; and figures 2A-B a schematic representation of a process device for performing the process of figure 1.

Device 10 (Figure 1) is shown in simplified form in the embodiment shown with the most important process steps according to the invention. Buffer 12, which can be monitored by means of sensor 14, is supplied to ultra-filtration device 20 by means of line 16. The current through line 16 can be monitored by means of sensor 18. The current supplied by line 16 is turned into ultra filtration device 20 are separated into a permeate and a filtrate. The separation can be monitored by means of sensor 22. The filtrate is removed from the process by means of line 24 and can be used for further processing. Conduit 26 provides reverse osmosis device 30 with the permeate. The supply of the permeate to reverse osmosis device 30 can be monitored by means of sensor 28. The permeate supplied through line 26 is separated in reverse osmosis device 30 into a permeate and a concentrate. The separation can be monitored by means of sensor 32. The permate from the reverse osmosis device 30 is discharged through line 36 and can be used for further processing. The discharge of the permeate from reverse osmosis device 30 can be monitored by means of sensor 40. The concentrate from the reverse osmosis device 30 is discharged via line 34 and can be used for further processing. The discharge of the concentrate from reverse osmosis device 30 can be monitored by means of sensor 38.

In one embodiment, sensors 14, 22 and 32 are adapted to measure, for example: flow rate and / or pressure and / or quantity and / or level and / or temperature and / or viscosity and / or color and / or acidity and / or weight and / or electrical conductivity and / or chemical composition.

In one embodiment, sensors 18, 28, 38 and 40 are adapted to measure the steam speed. Furthermore, sensors 18, 28, 38 and 40 can be designed for measuring, for example: pressure and / or quantity and / or level and / or temperature and / or viscosity and / or color and / or acidity and / or weight and / or electrical conductivity and / or chemical composition. Those skilled in the art will appreciate that sensors 14, 18, 22, 28, 32, 38 and 40 can include multiple sub-sensors, the sub-sensors being adapted to measure a single parameter. The person skilled in the art furthermore understands that sensors 14, 18, 22, 28, 32, 38 and 40 can be arranged in another suitable location and that these can optionally be arranged.

Reverse osmosis system 50 in the operating state (Figure 2A) includes ultra-filtration device 20, with sensor 28 optionally mounted and not operatively connected to lead-through element 52 through conduit 26, and reverse osmosis device 30 and operatively coupled to water supply 198 and operatively is coupled to lead-through element 52 by means of line 200. Line 200 can be monitored by means of sensor 202. Reverse osmosis device 30 consists of different reverse osmosis elements, 70, 98, 126 and 154, which can function independently of each other and separately from each other in reverse osmosis device 30. Further, reverse osmosis device 30 includes a pump 56 for providing an input. Feed-through element 58 provides power to line 60 and / or 62. The current in line 62 can be monitored by sensor 64. The current in line 60 is pumped by pump 66 into reverse osmosis element 70, the current in line 60 can be monitored by sensor 68. A separation can take place in reverse osmosis element 70 through membrane 72. Reverse osmosis element 70 provides a permeate to conduit 74 and a concentrate to conduit 78. The concentrate in conduit 78 passes through conduit element 80 to conduit 62 and / or conduit 86, wherein the flow into conduit 86 may can be monitored by means of sensor 88. The permeate in line 74 can be monitored by sensor 76. Feed-through element 82 supplies line 86 and / or 84 and / or 90 with a current. The current in line 90 can be monitored by sensor 92. The current in line 84 is pumped by pump 94 into reverse osmosis element 98, the current in line 84 can be monitored by sensor 96. A separation can take place in reverse osmosis element 98 through membrane 100. Reverse osmosis element 98 provides a permeate to conduit 166 and a concentrate to conduit 102. The concentrate in conduit 102 passes through conduit element 104 to conduit 90 and / or conduit 106, wherein the flow into conduit 106 may can be monitored by means of sensor 108. The permeate in line 166 can be monitored by sensor 122 and supplied to line 74 by means of feed-through element 124. Feed-through element 110 supplies line 106 and / or 112 and / or 116 with a current. The current in line 112 can be monitored by sensor 114. The current in line 116 is pumped by pump 118 into reverse osmosis element 126, the current in line 116 can be monitored by sensor 120. A separation can take place in reverse osmosis element 126 through membrane 128. Reverse osmosis element 126 provides a permeate to conduit 168 and a concentrate to conduit 130. The concentrate in conduit 130 goes through conduit element 132 to conduit 112 and / or conduit 134, the flow in conduit 134 being can be monitored by means of sensor 136. The permeate in line 168 can be monitored by sensor 150 and supplied to line 74 by means of feed-through element 152. Feed-through element 138 supplies line 134 and / or 140 and / or 144 with a current. The current in line 140 can be monitored by sensor 142. The current in line 144 is pumped by pump 146 into reverse osmosis element 154, the current in line 144 can be monitored by sensor 148. A separation can take place in reverse osmosis element 154 through membrane 156. Reverse osmosis element 154 provides a permeate to conduit 170 and a concentrate to conduit 158. The concentrate in conduit 158 passes through conduit element 160 to conduit 140 and / or conduit 162, wherein the flow into conduit 162 may can be monitored by means of sensor 164. The permeate in line 170 can be monitored by sensor 172 and supplied to line 74 by means of feed-through element 174. The current in line 74 can be supplied to output 176. The current in line 162 can be provided to by-pass 178. By-pass 178 comprises line 182 which is operatively connected to controller 186. Controller 186 controls the flow of the concentrate n to line 184 and lead-through element 194 to subsequently leave reverse osmosis device 30 via output 196.

Furthermore, by-pass 178 includes line 188 operatively connected to controller 192. Controller 192 is closed during circulation / recirculation when reverse osmosis device 30 is operating. Controller 192 is operatively coupled to line 190. Line 190 is operatively coupled to lead-through element 194.

Reverse osmosis system 50 in the cleaning state (Figure 2B) includes ultra-filtration device 20, with sensor 28 optionally mounted and connected to lead-through element 52 by line 26, and reverse osmosis device 30. Reverse osmosis device 30 consists of various reverse osmosis elements 70, 98, 126 and 154, which can function independently of each other and can be arranged separately from each other in reverse osmosis device 30. Further, reverse osmosis device 30 includes a pump 56 for providing an input. Feed-through element 58 provides line 60 and / or 62 with a current. The current in line 62 can be monitored by sensor 64. The current in line 60 is pumped by pump 66 into reverse osmosis element 70, the current in line 60 can be monitored by sensor 68. A separation can take place in reverse osmosis element 70 through membrane 72. Reverse osmosis element 70 provides a permeate to conduit 74 and a concentrate to conduit 78. The concentrate in conduit 78 passes through conduit element 80 to conduit 62 and / or conduit 86, wherein the flow into conduit 86 may can be monitored by means of sensor 88. The permeate in line 74 can be monitored by sensor 76. Feed-through element 82 supplies line 86 and / or 84 and / or 90 with a current. The current in line 90 can be monitored by sensor 92. The current in line 84 is pumped by pump 94 into reverse osmosis element 98, the current in line 84 can be monitored by sensor 96. A separation can take place in reverse osmosis element 98 through membrane 100. Reverse osmosis element 98 provides a permeate to conduit 166 and a concentrate to conduit 102. The concentrate in conduit 102 passes through conduit element 104 to conduit 90 and / or conduit 106, wherein the flow into conduit 106 may can be monitored by means of sensor 108. The permeate in line 166 can be monitored by sensor 122 and supplied to line 74 by means of feed-through element 124. Feed-through element 110 supplies line 106 and / or 112 and / or 116 with a current. The current in line 112 can be monitored by sensor 114. The current in line 116 is pumped by pump 118 into reverse osmosis element 126, the current in line 116 can be monitored by sensor 120. A separation can take place in reverse osmosis element 126 through membrane 128. Reverse osmosis element 126 provides a permeate to conduit 168 and a concentrate to conduit 130. The concentrate in conduit 130 goes through conduit element 132 to conduit 112 and / or conduit 134, the flow in conduit 134 being can be monitored by means of sensor 136. The permeate in line 168 can be monitored by sensor 150 and supplied to line 74 by means of feed-through element 152. Feed-through element 138 supplies line 134 and / or 140 and / or 144 with a current. The current in line 140 can be monitored by sensor 142. The current in line 144 is pumped by pump 146 into reverse osmosis element 154, the current in line 144 can be monitored by sensor 148. A separation can take place in reverse osmosis element 154 through membrane 156. Reverse osmosis element 154 provides a permeate to conduit 170 and a concentrate to conduit 158. The concentrate in conduit 158 passes through conduit element 160 to conduit 140 and / or conduit 162, wherein the flow into conduit 162 may can be monitored by means of sensor 164. The permeate in line 170 can be monitored by sensor 172 and supplied to line 74 by means of feed-through element 174. The current in line 74 can be supplied to output 176. The current in line 162 can be provided to lead-through element 160. By-pass 178 includes line 182 operatively connected to controller 186. Controller 186 is closed during cleaning. Furthermore, by-pass 178 includes line 188 operatively connected to controller 192. Controller 192 is opened during cleaning of reverse osmosis device 30. Controller 192 is operatively coupled to conduit 190. Conduit 190 is operatively coupled to lead-through element 194. Conduit 196 provides in a stream, for example of water, to feed-through element 194. In the cleaning state, outlet 196 serves as inlet for reverse osmosis device 30.

Feed-through elements 52, 58, 80, 82, 104, 110, 124, 132, 138, 150, 160, 174, 180 and 194 are adapted to feed the current. Examples of embodiments of feed elements 52, 58, 80, 82, 104, 110, 124, 132, 138, 150, 160, 174, 180 and 194 are: T-piece, two-way valve, three-way valve.

Sensors 28, 64, 68, 76, 88, 92, 96, 108, 114, 120, 122, 136, 142, 148, 150, 164, 172 and 202 are adapted to measure the steam speed. Sensors 28, 64, 68, 76, 88, 92, 96, 108, 114, 120, 122, 136, 142, 148, 150, 164, 172 and 202 can also be designed for measuring, for example: pressure and / or or amount and / or level and / or temperature and / or viscosity and / or color and / or acidity and / or weight and / or electrical conductivity and / or chemical composition.

Those skilled in the art will appreciate that sensors Sensors 28, 64, 68, 76, 88, 92, 96, 108, 114, 120, 122, 136, 142, 148, 150, 164, 172 and 202 can include multiple sub-sensors, wherein the sub-sensors are adapted to measure a single parameter. Furthermore, the person skilled in the art understands that sensors 28, 64, 68, 76, 88, 92, 96, 108, 114, 120, 122, 136, 142, 148, 150, 164, 172 and 202 can be arranged in another suitable location and that these can be applied optionally. In a preferred embodiment, pump 56 provides sufficient supply for the system. In a preferred embodiment, a current is supplied to the lines in an operating state of:

Conduit from figure 2A: Volume (m ³ / hour) Lead 54 50 Lead 62 50 Lead 60 100 Leadership 74 12 Lead 78 88

Lead 86 38 Conduit 90 62 Lead 84 100 Lead 166 11 Lead 102 89 Line 106 27 Conduit 112 73 Lead 116 100 Lead 168 9 Conduit 130 91 Lead 134 18 Conduit 140 82 Lead 144 100 Conduit 170 8 Lead 158 92 Lead 162 10 Drain 176 40

In a preferred embodiment, a current is supplied to the pipes in a cleaning state of:

Conduit from figure 2A: Volume (m / hour) Lead 54 50 Lead 62 5 Lead 60 45 Leadership 74 2 Lead 78 43 Lead 86 48 Conduit 90 3 Lead 84 45 Lead 166 1 Lead 102 44 Line 106 3 Conduit 112 47 Lead 116 45 Lead 168 1

Conduit 130 44 Lead 134 2 Conduit 140 46 Lead 144 45 Conduit 170 1 Lead 158 44 Lead 162 45 Drain 176 5

The various reverse osmosis elements can be cleaned separately by disconnecting them. Cleaning of ultra-filtration device 20 is done per module. The advantage of this is that the time that the system is out of use is reduced to a minimum. An additional advantage is that the system can remain in continuous operation.

The present invention is by no means limited to the above described preferred embodiments thereof. The requested rights are determined by the following claims within the scope of which many modifications are conceivable.

Claims (4)

Conclusions A method of operating a reverse osmosis (RO) process for treating a process stream, the method comprising: supplying a process flow to a treatment device; treating the process stream in the treatment device; cleaning and / or stopping the treatment of the process stream; and realizing a plug flow for removing an amount of process flow present in the process. A method according to claim 1, wherein the step of realizing a plug flow comprises controlling one or more process pumps with switching means. A device for operating a reverse osmosis (RO) process for treating a process stream, the device comprising: a feed for supplying a process stream to be treated; an RO installation adapted to handle the process flow; an output for discharging the treated process stream; and switching means for switching the device between operating state and a cleaning state in which a plug flow is provided for removing an amount of process flow present in the process. Device as claimed in claim 3, wherein the switching means comprise a controller for controlling one or more process pumps. 1/3 2/3 3/3