Method for the prevention of biofilm and sedimentation in springs

Abstract

Method for the prevention and/or removal of biofilm and sediment formation in borehole tubes or distribution tubes, with the following steps: (i) mounting one or more ultrasonic transducers (9, 9′) on an aboveground part of the tube; (ii) sending the ultrasonic waves whereby both the power and the frequency of the ultrasonic waves are varied in time, with a frequency between 20 and 60 kHz and a power between 1 and 6 Watt for smaller tubes and between 6 and 40 Watt for larger tubes; (iii) sending the varying ultrasonic waves through the water that flows or is pumped through the tube; (iv) providing an automatic interruption of the effect of the ultrasonic waves when the flow of the water through the tube stops, either by shutting off the transducers, or by the automatic operation of a non-return valve which interrupts the water column between the transducer and the underlying mass of water.

Claims

1. A method for prevention and/or removal of biofilm and for prevention of sediment formation in a borehole tube or a distribution tube of a water spring, the method comprises: (i) mounting one or more ultrasonic transducers on an aboveground part of the borehole tube or the distribution tube; (ii) sending ultrasonic waves of the one or more ultrasonic transducers whereby both a power and a frequency of the ultrasonic waves are varied in time, and whereby the frequency is controlled between 20 and 60 KHz and the power is controlled between 1 and 6 Watt for smaller tubes with a diameter <5 cm and between 6 and 40 Watt for larger tubes with a diameter >5 cm; (iii) sending the varying ultrasonic waves through a water that flows or is pumped through the borehole tube or the distribution tube to prevent and/or remove the biofilm and to prevent the sediment formation in the borehole tube or the distribution tube; and (iv) automatically interrupting an effect of the ultrasonic waves when the flow of the water through the borehole tube or the distribution tube stops, whereby the effect of the ultrasonic waves is interrupted, either due to the one or more ultrasonic transducers shutting off automatically immediately or after an elapse of a waiting period of time from when the flow of the water through the borehole tube or distribution tube stops, or immediately due to automatic operation of a non-return valve in the borehole tube or the distribution tube, the valve interrupting a water column between the one or more ultrasonic transducers and an underlying mass of the water as soon as a pump no longer pumps or there is no more waterflow from the water spring from which the water is pumped by the pump, wherein the non-return valve interrupting the water column between the one or more ultrasonic transducers and the underlying mass of water, is mounted upstream from the one or more ultrasonic transducers.

2. The method according to claim 1, wherein over a time span of 10 seconds at least five to eight different frequencies are sent through the one or more ultrasonic transducers.

3. The method according to claim 1, wherein the one or more ultrasonic transducers are mounted on the aboveground part of the borehole tube or the distribution tube against a steel of the borehole tube or the distribution tube itself, and do not make direct contact with the underlying mass of the water in the borehole tube or the distribution tube.

4. The method according to claim 1, wherein the one or more ultrasonic transducers are mounted on the aboveground part of the borehole tube or the distribution tube and via an opening in the borehole tube or the distribution tube itself, make direct contact with the mass of water in the borehole tube or the distribution tube.

5. The method according to claim 1, wherein a sediment filter is provided with which an amount of sediment in the water pumped by the pump can be filtered and measured, such that when the measured amount of sediment over a certain time span falls under a certain limit value, the one or more ultrasonic transducers is shut off.

6. A method for prevention and/or removal of biofilm and for prevention of sediment formation in a borehole tube or a distribution tube of a water spring, the method comprises: (i) mounting one or more ultrasonic transducers on an aboveground part of the borehole tube or the distribution tube; (ii) sending ultrasonic waves of the one or more ultrasonic transducers whereby both a power and a frequency of the ultrasonic waves are varied in time, and whereby the frequency is controlled between 20 and 60 kHz and the power is controlled between 1 and 6 Watt for smaller tubes with a diameter <5 cm and between 6 and 40 Watt for larger tubes with a diameter >5 cm; (iii) sending the varying ultrasonic waves through a water that flows or is pumped through the borehole tube or the distribution tube to prevent and/or remove the biofilm and to prevent the sediment formation in the borehole tube or the distribution tube; and (iv) automatically interrupting an effect of the ultrasonic waves when the flow of the water through the borehole tube or the distribution tube stops, whereby the effect of the ultrasonic waves is interrupted, either due to the one or more ultrasonic transducers shutting off automatically immediately or after an elapse of a waiting period of time from when the flow of the water through the borehole tube or distribution tube stops, or immediately due to automatic operation of a non-return valve in the borehole tube or the distribution tube, the valve interrupting a water column between the one or more ultrasonic transducers and an underlying mass of the water as soon as a pump no longer pumps or there is no more waterflow from the water spring from which the water is pumped by the pump, wherein a sediment filter is provided with which an amount of sediment in the water pumped by the pump can be filtered and measured, such that when the measured amount of sediment over a certain time span falls under a certain limit value, the one or more ultrasonic transducers is shut off.

7. The method according to claim 6, wherein over a time span of 10 seconds at least five to eight different frequencies are sent through the one or more ultrasonic transducers.

8. The method according to claim 6, wherein the one or more ultrasonic transducers are mounted on the aboveground part of the borehole tube or the distribution tube against a steel of the borehole tube or the distribution tube itself, and do not make direct contact with the underlying mass of the water in the borehole tube or the distribution tube.

9. The method according to claim 6, wherein the one or more ultrasonic transducers are mounted on the aboveground part of the borehole tube or the distribution tube and via an opening in the borehole tube or the distribution tube itself, make direct contact with the underlying mass of the water in the borehole tube or the distribution tube.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) With the intention of better showing the characteristics of the present disclosure, a few applications of the method for preventing biofilm and sedimentation in water springs according to the present disclosure are described hereinafter by way of an example, without any limiting nature, with reference to the accompanying drawings, wherein:

(2) FIG. 1 schematically and in cross-section shows a water spring equipped with an ultrasonic sound source according to the present disclosure;

(3) FIG. 2 shows a part of FIG. 1 indicated with F2 on a larger scale;

(4) FIG. 3 schematically shows a series of different frequencies sent by an ultrasonic sound source over a time span of 10 seconds through the transducer;

(5) FIG. 4 in cross-section shows a non-return valve according to the present disclosure upstream from the ultrasonic transducer.

DETAILED DESCRIPTION

(6) FIG. 1 schematically shows a water spring 1, from which water 2 is pumped up by a pump 3, which is located under the water table 4, and pumps the water 2 up through a vertical riser tube 5 which, once aboveground, shows an elbow 6 and continues as a horizontal tube 7 over the ground 8. An ultrasonic sound source such as an ultrasonic transducer 9 can be mounted in several locations aboveground.

(7) In a first variant the ultrasonic transducer 9 is mounted on the elbow 6, and the transducer 9 is connected to a control box 10 for sending the ultrasonic waves, whereby the transducer 9 makes contact with the metal of the riser tube 5 and not directly with the water column 11 in the tube.

(8) In a second variant the ultrasonic transducer 9′ is mounted on the horizontal tube 7 on the surface and is also connected to a control box 10′ for sending the ultrasonic waves, but in this case the transducer 9′ is in direct contact with the water in the horizontal tube 7 through an opening 12 in the tube against which the transducer 9′ is positioned.

(9) In some embodiments, a sediment filter 13 is provided with which the amount of sediment carried along in the pumped up water can be filtered and measured. When the measured amount of sediment falls under a certain limit value over a given time span, said measured amount can be used to shut off the ultrasonic transducer 9. A non-return valve 14 can be provided upstream from the transducer 9′.

(10) FIG. 2 shows a detail of FIG. 1 on a larger scale, illustrating that the ultrasonic transducer 9 which is mounted on the elbow 6 of the riser tube 5, is in direct contact with the metal wall of the elbow 6, and does not make direct contact with the water 2 that flows through the riser tube 5 to the surface. In this case the ultrasonic waves propagate via the metal of the riser tube 5.

(11) FIG. 3 schematically shows an example of a series 15 of, in this case, five different frequencies 15a-15e between 20 kHz and 60 kHz, which an ultrasonic sound source sends over a time span of 10 seconds through the transducer, controlled by a control box 10.

(12) FIG. 4 shows the non-return valve 14 indicated with F4 on FIG. 1 on a larger scale. The non-return valve 14 opens under the influence of the pumped up flow of water 2, but closes when no more water is pumped up or pushed up by the water spring with which the horizontal tube 7 is connected, such that the water column in the riser tube 5 is interrupted and the ultrasonic waves no longer penetrate into the water spring.

(13) The operation of the ultrasonic installation 1 is very simple and as follows.

(14) The one or more ultrasonic transducers 9, 9′ on an aboveground part 6.7 of the riser tube 5 send ultrasonic waves, of which both the power and the frequency of the ultrasonic waves are varied in time, and whereby the frequency is controlled between 20 and 60 kHz and the power is controlled between 1 and 6 Watt for smaller tubes with a diameter <5 cm, and between 6 and 40 Watt for larger tubes with a diameter >5 cm by a control box 10, 10′ which is connected to the one or more transducers 9, 9′.

(15) The effect of the ultrasonic waves, namely preventing and combating biofilm and sediment in the tubes, is automatically interrupted when the flow of the water through the tube stops, because the pump which makes the waterflow through the tube stops or is shut off or because of another cause. This occurs either due to the automatic shut off the one or more transducers 9, 9′, with or without a set waiting period of for example a week, or immediately due to the automatic operation of a non-return valve 14 in the tube 7, said valve interrupting the water column between the ultrasonic transducer 9′ and the underlying mass of water 2 in the water spring as soon as the pump no longer pumps or the water spring no longer produces any flow.

(16) As long as the ultrasonic waves are sent through the water in the tubes, the formation of biofilm and ultimately sediment is prevented or combated and the water spring remains operational. When the water in the water spring is stationary, it may be better to interrupt the ultrasonic waves, because after some time they can loosen already formed biofilm or sediment, such that the loosened biofilm sinks down as debris and causes blockage of the tubes or the water spring itself.

(17) The protective effect of the ultrasonic waves can extend over long distances, even kilometres in tubes with a large diameter. This does not apply to tubes with a small diameter in which the presence of regulators or constrictions to control the waterflow often prevents an unhindered propagation of the ultrasonic waves.

(18) Instead of mounting one or more ultrasonic sound sources in the form of one or more ultrasonic transducers 9 or 9′ on an aboveground part of the borehole tube 6 or the distribution tube 7, alternatively they can be provided in the water, i.e. in the borehole under the water table, that is if there is sufficient space available to this end between the wall of the borehole and the pumping tube.

(19) This variant method requires the application of the other steps of the method according to the present disclosure.

(20) The present disclosure is not limited to the embodiments described as an example and shown in the drawings, but such a method for preventing biofilm and sedimentation in water springs can be realised according to different variants without departing from the scope of the present disclosure, as is defined in the following claims.