Retrofittable control unit for a softening apparatus

• US 20110132818A1
• Filed: 07/09/2009
• Published: 06/09/2011
• Est. Priority Date: 08/09/2008
• Status: Active Grant

• Current Assignee: Judo Wasseraufbereitung Gmbh (Dopslaff Grundstuecksgesellschaft)
• Original Assignee: Judo Wasseraufbereitung Gmbh (Dopslaff Grundstuecksgesellschaft)
• Inventors: Dopslaff, Carsten, Neidhardt, Klaus, Haug, Alexander, Soecknick, Ralf, Melcher, Siegfried
• Granted Patent: US 8,709,241 B2
• Time in Patent Office: Days
• US Class Current: 210/96.1
• CPC Class Codes: B01J 47/14 Controlling or regulating
• CPC Class Codes: B01J 49/85 Controlling or regulating devices therefor
• CPC Class Codes: C02F 1/008 Control or steering systems not provided for elsewhere in subclass C02F
• CPC Class Codes: C02F 1/42 by ion-exchange ion-exchange in general B01J
• CPC Class Codes: C02F 2209/001 Upstream control, i.e. monitoring for predictive control
• CPC Class Codes: C02F 2209/003 Downstream control, i.e. outlet monitoring, e.g. to check the treating agents, such as halogens or ozone, leaving the process
• CPC Class Codes: C02F 2209/05 Conductivity or salinity
• CPC Class Codes: C02F 2209/055 Hardness
• CPC Class Codes: C02F 2209/40 Liquid flow rate
• CPC Class Codes: C02F 2301/043 Treatment of partial or bypass streams
• CPC Class Codes: C02F 2303/16 Regeneration of sorbents, filters

Abstract

A control unit (1, 1a) for a softening device (2), comprising a primary inlet (4) for untreated water, a primary outlet (7) for blended water, a sensor for determining the water hardness of the untreated water WH_raw or the blended water WH_blend, a secondary outlet (5), a secondary inlet (6), a bypass line (9), a blending means which can be automatically adjusted for mixing a blended water flow V_blend(t) from a first partial flow (V(t)_part1soft of the secondary inlet (6) and a second partial flow V(t)_part2raw of the bypass line (9), and an electronic control means (11, 11a), wherein the control means (11, 11a) is designed to readjust the adjustment position of the blending means by means of the determined water hardness in such a fashion that the water hardness in the blended water flow V_blend(t) is adjusted to a predetermined desired value, is characterized in that the control unit (1, 1a) is designed in the form of an external control unit (1, 1a) for the softening device (2), wherein the control unit (1, 1a) has a control unit housing (3), the outer side of which is provided with the primary inlet (4), the primary outlet (7), the secondary outlet (5), and the secondary inlet (6), and wherein the control unit housing (3) contains the sensor, the bypass line (9), the blending means and the electronic control means (11, 11a). The inventive control unit enables partial softening of water on the basis of fully automatic blending, thereby utilizing already existing softening devices.

Claims

1. Control unit (1, 1a) for a softening device (2), wherein the control unit (1, 1a) comprises

a primary inlet (4) for untreated water,

a primary outlet (7) for blended water,

a sensor for determining the water hardness of the untreated water W_raw or the blended water WH_blend,

a secondary outlet (15) which is supplied with untreated water from the primary inlet (4),

a secondary inlet (6) which is supplied to the primary outlet (7),

a bypass line (9) which is guided parallel to the secondary outlet and the secondary inlet (6),

a blender which can be automatically adjusted for mixing a blended water flow V_blend(t) from a first partial flow V(t)_part1soft of the secondary inlet (6) and a second partial flow V(t)_part2raw of the bypass line (9),

an electronic control means (11, 11a), wherein the control means (11, 11a) is designed to readjust the adjustment position of the blender according to of the determined water hardness WH_raw or WH_blend in such a fashion that the water hardness in the blended water flow V_blend(t) is adjusted to a predetermined desired value, wherein

the control unit (1, 1a) is designed in the form of an external control unit (1, 1a) for the softening device (2), wherein the control unit (1, 1a) has a control unit housing (3), the outer side of which is provided with the primary inlet (4), the primary outlet (7), the secondary outlet (5) and the secondary inlet (6), and wherein the control unit housing (3) contains the sensor, the bypass line (9), the blender and the electronic control means (11, 11a).

2. Control unit (1, 1a) according to claim 1, wherein the sensor is designed as a conductivity sensor (16).

3. Control unit (1, 1a) according to claim 1 wherein the sensor is arranged in the untreated water area of the control unit (1, 1a).

4. Control unit (1, 1a) according to claim 1 wherein the control unit housing (3) is designed as an intermediate connecting piece.

5. Control unit (1, 1a) according to claim 1 wherein the control unit (1, 1a) further comprises at least two flow meters (12, 13) for direct or indirect determination of the partial flows V(t)_part1soft and V(t)_part2raw,

that the electronic control means (11, 11a) is designed to also readjust the adjustment position of the blender on the basis of the determined partial flows V(t)_part1soft and V(t)_part2raw, and that the control unit housing (3) also contains the at least two flow meters (12, 13).

6. Control unit (1, 1a) according claim 1 further comprising a first flow meter (12) arranged between the primary inlet (4) and the branching point (8) of the bypass line (9) for determining an overall untreated water inflow V(t)_rawall, and that-a second flow meter (13) arranged in the bypass line (9) for determining the second partial flow V(t)_part2raw.

7. Control unit (1, 1a) according to claim 6, wherein the control unit (1, 1a) has a measuring input (20) for a third flow meter (21) in order that a rinsing water flow V(t)_part3rinse can be determined for the electronic control (11, 11a),

and that the electronic control (11, 11a) is designed to determine the first partial flow V(t)_part1soft in accordance with the equation V(t)_part1soft=V(t)_rawall−

V(t)_part2raw−

V(t)_part3rinse.

8. Control unit (1, 1a) according to claim 1 further comprising a measuring device (17) is arranged in the blended water area in addition to the sensor for determining the concentration of the hardness components calcium and magnesium C_{hardnessblend} in the blended water flow V(t)_blend.

9. Control unit (1, 1a) according to claim 8, wherein the measuring device (17) is designed as titrator for titrimetric determination of the hardness components, or that the measuring device (17) comprises an ion-selective sensor, in particular, an ion-selective electrode.

10. Control unit (1, 1a) according to claim 1, further comprising an automatically actuatable stop valve (18) disposed directly downstream of the primary inlet (4), and that the electronic control (11, 11a) is designed to automatically close the stop valve (18) in case of a leakage.

11. Control unit (1, 1a) according claim 1 wherein the control unit (1, 1a) has a control terminal (22) for triggering regeneration of the softening device (2), and that the electronic control (11, 11a) is designed to determine, in dependence on the soft water withdrawals performed since the last triggered regeneration and on one or more associated defined untreated water hardnesses, a residual capacity of the softening device (2), and upon depletion thereof, to automatically issue a control pulse to the control terminal (22) for triggering regeneration.

12. Control unit (1, 1a) according to claim 11, wherein the sensor is designed as a conductivity sensor (16) for measuring the conductivity of the untreated water L_raw, and that the electronic control (11, 11a) is designed to derive an overall hardness I of the untreated water, which is used to control regeneration triggering, from the measured conductivity L_raw by way of a first calibration characteristic (F1), and to derive an overall hardness II of the untreated water, winch is used to control the blender, from the measured conductivity L_raw by way of a second calibration characteristic (F2).

13. Water softening system comprising a softening device (2) with a softener housing (2a) and an external control unit (1, 1a) according claim 1 wherein the control unit (1, 1a) is disposed outside of the softener housing (2a) and wherein the softener device (2) is connected at the secondary outlet (5) and the secondary inlet (6) of the control unit (1, 1a) to the outer side of the control unit housing (3).

14. Water softening system according to claim 13 with a control unit (1, 1a) according to claim 11 wherein the water softening system has a supply container (23) for regenerant solution (23a) and also means for automatic performance of regeneration of the softening device, in particular, comprising a regeneration valve (24) that can be driven by a servomotor (25), and that the control terminal (22) is connected to the means for automatic performance of regeneration.

15. The use of a water softening system according to any one of the claim 13,

wherein the softening device (2) has its own blender, and wherein the separate blending of the softening device (2) is closed such that the softening device (2) only provides completely softened water.