Process water sampling immersion probe

Abstract

The present invention relates to a process water sampling immersion probe (10) comprising a filter module (20) comprising a flat filter screen (22, 23) and a sample suction opening (28) through which filtered sample water is pumped from the filter module (20) to an analyzer unit (80), and a rigid retention mechanism (90), the invention relates to a filter module (20) comprising a rigid holding mechanism (90) for holding the filter module (20), a swivel bearing arrangement (30) being provided, which defines a stationary axis of rotation (R) and connects the filter module (20) to the rigid holding mechanism (90) such that the filter module (20) can be rotated within a rotation sector (S) having a rotation angle of at least 10 DEG.

Description

Process water sampling immersion probe Technical Field

[0001] This invention relates to a process water sampling immersion probe for continuously filtering water samples from water. Background Technology

[0002] The process water sampling immersion probe is used as part of a process water analysis setup to analyze one or more analytes in the water, such as one or more analytes in wastewater in a wastewater tank (which is part of a wastewater treatment plant).

[0003] US 6,379,621 B1 discloses a fixed water sampling immersion probe arrangement. This arrangement includes a streamlined filter module held in place within a wastewater tank by a robust retaining structure. Wastewater in the tank flows in the general flow direction, but due to various influencing factors, the flow direction may vary within an angle of + / -30° or even greater, causing the wastewater to impact the filter module from different angles. When the filter module is not perfectly collinear with the wastewater flow, blockage may occur on the back side of the filter module. Summary of the Invention

[0004] The purpose of this invention is to provide a process water immersion probe with improved self-cleaning quality.

[0005] This objective is achieved by using the process water sampling immersion probe featured in claim 1.

[0006] A process water sampling immersion probe for continuously filtering water samples from water (preferably from wastewater) includes a filter module having a filter screen, which is preferably a substantially planar filter screen, more preferably a planar filter screen standing in a vertical plane.

[0007] The filter module is equipped with a suction opening through which filtered sample water is pumped from the filter module to the land-based analyzer unit. During operation, the filter module is immersed in wastewater in the wastewater tank. Rigid retaining mechanisms and static retaining structures fixed to the wastewater tank assembly hold the filter module in the proper position within the wastewater tank.

[0008] The process water sampling immersion probe is equipped with a rotary bearing arrangement having a defined axis of rotation and mechanically connecting the filter module to a robust retaining mechanism and rigid retaining structure, allowing the filter module to rotate about the axis of rotation within a rotating sector. The rotating sector of the rotary bearing arrangement has an angle of at least 10°, allowing the filter module to rotate relative to its central position at a rotation angle of + / - 5°. The central position of the rotating filter module corresponds to the overall flow direction of the wastewater within the wastewater tank.

[0009] Because the filter module can rotate, it can be oriented to adapt to the local direction of wastewater flow, keeping the flow characteristics at the surface of the planar filter screen substantially constant. Therefore, the planar filter screen is typically not located on the back side, ensuring that tangential laminar flow and / or directly adjacent water flow are always present at the surface of the filter screen. This tangential laminar flow and / or directly adjacent water flow prevents substantial clogging and growth of clogging structures at the filter screen.

[0010] Since the filter module is typically collinear with the wastewater flow, the holding force required to keep the filter module in place is relatively low, allowing the rigid holding structure to be configured to be less rigid.

[0011] Preferably, the defined axis of rotation of the rotary bearing arrangement is arranged completely vertically.

[0012] Preferably, the filter module is fixed to the rotary bearing arrangement using its end portion, such that the filter module is hinged to the rigid retaining structure via the rotary bearing arrangement as a marker to the marked pole. The complete filter module is always located downstream of the rotary bearing arrangement.

[0013] Preferably, the rotary bearing arrangement comprises at least two separate rotary bearing units, more preferably located at two vertical end portions of the filter module. Preferably, the rotary bearing arrangement comprises at least one bearing unit of the friction bearing type. Friction bearings are mechanically simpler and more reliable than rolling bearings in harsh environments.

[0014] Preferably, the rotary bearing arrangement is provided with a rotation limiting device that limits the maximum rotation angle of a possible rotary sector. Preferably, the rotation limiting device limits the maximum total rotation angle of the rotary sector to less than 91°, more preferably less than 75°. In a more preferred embodiment, for a total rotation angle of at least 30°, the rotation angle is at least + / - 15°. In another preferred embodiment, the total rotation angle is between 30° and 75°.

[0015] The rotation limiting device prevents the filter module from rotating completely 360° relative to the rigid retaining structure, making it relatively simple and durable to achieve fluid and electrical connections between the rotating filter module and the rigid retaining structure.

[0016] Preferably, at least one bearing housing of the friction bearing unit is made of plastic, so that the friction of the friction bearing unit is relatively low.

[0017] Preferably, the rotating bearing arrangement includes a wet bearing unit that is open to ambient fluids, particularly to the wastewater in which the filter module is immersed. The wet bearing concept eliminates all the sealing measures required for dry bearing units. However, the wet bearing unit needs to be configured and constructed to be relatively robust against water, debris, and clogging.

[0018] Preferably, a flexible fluid hose is provided for fluidly connecting the sample aspiration opening of the filter module to a downstream fixed sample line fixed to the rigid retaining structure. Because the rotary bearing arrangement is equipped with a rotation limiting device, a fluid connection can be achieved relatively simply and cost-effectively between the filter module and the fixed fluid line (at the rigid retaining structure).

[0019] Preferably, the rotary bearing arrangement includes at least one rotary bearing unit and a vertical protective cover surrounding the rotary bearing unit. The vertical protective cover is positioned upstream of the rotary bearing unit, thus protecting the rotary bearing unit from any direct impact from particulate components in the wastewater flow. Attached Figure Description

[0020] An embodiment of the invention is described below with reference to the accompanying drawings, wherein

[0021] Figure 1 schematically illustrates a process water analysis setup including a process water sampling immersion probe, which is immersed in wastewater in a wastewater tank.

[0022] Figure 2 shows the vertical cross-section II-II of the process water sampling immersion probe in Figure 1, and

[0023] Figure 3 shows the horizontal profile III-III of the process water sampling immersion probe in Figures 1 and 2. Detailed Implementation

[0024] Figure 1 schematically illustrates a process water analysis arrangement 100 for continuously analyzing water samples from wastewater W. Wastewater W continuously flows into wastewater tank 110 through tank inlet 112 and continuously flows out of wastewater tank 110 through tank outlet 114, resulting in a substantially continuous wastewater flow F with a substantially constant flow direction. Wastewater tank 110 is part of a wastewater treatment plant (not shown). The process water analysis arrangement 100 is provided for almost continuously determining the concentration of one or more analytes (e.g., ammonium and / or phosphate) in wastewater W.

[0025] The process water analysis setup 100 includes a process water sampling immersion probe 10, which is fully immersed in the wastewater W and held in place by a robust holding structure 90 or rigid holding structure mounted to the boundary of the wastewater tank 110. The immersion probe 10 is fluidly and electronically connected to a land-based analyzer unit 80, which includes an electric sampling pump 82 and an analyzer device 84 for analyzing the concentration of one or more analytes in a filtered water sample of the wastewater W.

[0026] The immersion probe 10 includes a flat, planar, and rectangular filter module 20 located in a vertical plane xz and having two parallel vertical filter screens 22 and 23 that define a filter module cavity 25 therebetween. The filter module 20 includes a horizontal top filter module wall 29 with a sample aspiration opening 28 through which filtered sample water is pumped by a sample pump 82. The sample water is pumped from the filter module 20 to the analyzer device 84 of the analyzer unit 80 via a flexible fluid hose 92' and a downstream fixed sample line 92. The filter module 20 is not equipped with any mechanical cleaning devices, and in particular, it is not equipped with any air bubble generator to create an air bubble curtain.

[0027] The process water sampling immersion probe 10 is provided with a rotary bearing arrangement 30 defining a vertical axis of rotation R. This rotary bearing arrangement 30 connects the rotary filter module 20 to a vertical hollow bearing axis tube 90' ​​held in place by a rigid retaining structure 90. The rotary bearing arrangement 30 includes two separate wet and friction rotary bearing units 32, 32'. Each rotary bearing unit 32, 32' includes an inner bearing housing 34, 34' made of a plastic body, which defines a radial bearing cylinder 36 and an axial bearing ring body 35, and includes an outer bearing housing 40, 40' as shown in Figures 2 and 3. The cylindrical outer bearing housing 40, 40' is defined by a complex metal or plastic body 42, which also defines a radially fixed nose 47. This fixed nose 47 is fixed to the filter module end portion 20' of the filter module 20, such that the filter module 20 is hinged to the bearing axis tube 90' ​​as a marker post.

[0028] As shown in Figure 3, both rotary bearing units 32 and 32' are further provided with a rotation limiting device 60, which limits the rotary sector S to a maximum total rotation angle of 60°. The rotation limiting device 60 is limited by two tangential rotation stops 46 and 46' in each outer bearing housing 40 and 40', and by two cooperating tangential rotation stops 48 and 48', which are limited by stop noses 49 in the corresponding inner bearing housings 34 and 34'.

[0029] The rotary bearing units 32 and 32' are protected by cylindrical vertical protective covers 99 surrounding the rotary bearing units 32 and 32', thus protecting the rotary bearing units 32 and 32' from the direct impact of particulate components in the wastewater flow.

[0030] In the attached diagram, the vertical direction is indicated by z, the horizontal longitudinal direction of the water flow F is indicated by x, and the horizontal direction is indicated by y.

Claims

1. A process water sampling immersion probe (10), comprising: A filter module (20) includes a planar filter screen (22, 23) and a sample aspiration opening (28) through which filtered sample water is pumped from the filter module (20) to the analyzer unit (80), and a rigid holding structure (90) for holding the filter module (20), wherein a rotary bearing arrangement (30) is provided, the rotary bearing arrangement (30) defining a stationary axis of rotation (R) and connecting the filter module (20) to the rigid holding structure (90) so that the filter module (20) can rotate within a rotating sector (S) having a rotation angle of at least 10°.

2. The process water sampling immersion probe (10) as claimed in claim 1, wherein the axis of rotation (R) defined by the rotary bearing arrangement (30) is arranged vertically.

3. The process water sampling immersion probe (10) as described in any of the preceding claims, wherein, The filter module (20) is secured to the rotary bearing arrangement (30) using the end portion (20') of the filter module.

4. The process water sampling immersion probe (10) as described in any of the preceding claims, wherein the rotary bearing arrangement (30) is provided with at least two separate rotary bearing units (32, 32').

5. The process water sampling immersion probe (10) as claimed in any of the preceding claims, wherein the rotary bearing arrangement (30) is provided with at least one bearing unit (32, 32') of the friction bearing type.

6. The process water sampling immersion probe (10) as claimed in any of the preceding claims, wherein the rotary bearing arrangement (30) is provided with a rotation limiting device (60) that limits the maximum rotation angle of the possible rotary sector (S).

7. The process water sampling immersion probe (10) as claimed in claim 6, wherein the rotation limiting device (60) limits the maximum rotation angle of the rotating sector (S) to less than 91°, preferably less than 75°.

8. The process water sampling immersion probe (10) as described in any one of claims 5 to 7, wherein at least one bearing housing (34) of the bearing unit (32, 32') is made of plastic.

9. The process water sampling immersion probe (10) as claimed in any of the preceding claims, wherein the rotary bearing arrangement (30) is provided with wet bearing units (32, 32') that are fluidly open to the environment.

10. The process water sampling immersion probe (10) as described in any of the preceding claims, wherein, A flexible fluid hose (92') is provided, which fluidly connects the sample aspiration opening (28) of the filter module (20) to a downstream fixed sample line (92) fixed to the rigid retaining structure (90).

11. The process water sampling immersion probe (10) as claimed in any of the preceding claims, wherein the rotary bearing arrangement (30) is provided with at least one rotary bearing unit (32, 32') and a vertical protective cover (99) surrounding the rotary bearing unit (32, 32').

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