System for Controlling the Concentration of a Detrimental Substance in a Sewer Network

• US 20090242468A1
• Filed: 10/17/2005
• Published: 10/01/2009
• Est. Priority Date: 10/17/2005
• Status: Abandoned Application

• Current Assignee: YARA International ASA
• Original Assignee: YARA International ASA
• Inventors: Weissenberger, Jürgen, Aesoy, Anette, Corben, Tim
• Application Number:
  US12/083,635
• Publication Number:
  US 20090242468A1
• Time in Patent Office: Days
• US Class Current: 210/96.100
• CPC Class Codes: C02F 1/008 Control or steering systems not provided for elsewhere in subclass C02F
• CPC Class Codes: C02F 1/72 by oxidation C02F1/4672 takes precedence
• CPC Class Codes: C02F 2201/009 Apparatus with independent power supply, e.g. solar cells, windpower or fuel cells
• CPC Class Codes: C02F 2209/008 comprising telecommunication features, e.g. modems or antennas
• CPC Class Codes: C02F 2209/02 Temperature
• CPC Class Codes: C02F 2209/265 in the gas phase
• CPC Class Codes: C02F 2209/40 Liquid flow rate
• CPC Class Codes: C02F 2303/02 Odour removal or prevention of malodour
• CPC Class Codes: C02F 2307/08 Treatment of wastewater in the sewer, e.g. to reduce grease, odour
• CPC Class Codes: Y02A 20/212 Solar-powered wastewater sewage treatment, e.g. spray evaporation

Abstract

The invention relates to a system for controlling the concentration of a detrimental substance, in particular H₂S, in a sewer network. The system comprises a monitoring device arranged at a monitoring location in the sewer network and at least one dosing controller arranged at a dosing location upstream the monitoring location. The monitoring device is arranged for providing a signal indicating a measured H₂S concentration at the monitoring location and for transmitting a radio frequency signal carrying information about the H₂S concentration. The dosing controller is arranged for receiving the radio frequency signal, deriving a concentration signal based on the radio frequency signal, calculating a dose of a preselected additive based on the derived concentration signal, and supplying a dosing signal to a dosing device, causing the dosing device to add the calculated dose at the dosing location. Advantageously, the calculating of a dose also takes into account critical process indicators acquired at the dosing location. A main controller is arranged to communicate with the at controllers, and various control tasks are distributed among the main controller and the dosing controllers.

Claims

1-18. -18. (canceled)

19. System for controlling the concentration of a detrimental substance in a sewer network, comprising:

a monitoring device (200), arranged for

providing a signal indicating a measured concentration of said detrimental substance at a monitoring location (270) in said sewer network, and

transmitting a signal carrying information about said concentration, and a dosing controller (100), arranged for

receiving said signal carrying information about said concentration,

deriving a concentration signal based on said received signal,

calculating a dose of an additive based on said derived concentration signal, said additive being selected in order to counterbalance the effect of the detrimental substance, and

supplying a dosing signal to a dosing device (160), causing the dosing device (160) to add said calculated dose at a dosing location (182) in said sewer network, wherein

said monitoring device comprises a time controlled radio frequency transmitter adapted to transmit said signal carrying information about said concentration as a radio frequency signal, the radio frequency transmitter being activated

at regular time intervals or

whenever the concentration indicating signal has changed, with an adjustable threshold for trigging transmission.

20. System according to claim 19, wherein said dosing controller is further arranged to calculate said dose of said additive based on a critical process indicator measured at the dosing location (182).

21. System according to claim 20, wherein said critical process indicator is included in the following group of signals:

a flow measurement signal, a temperature measurement signal, a sewage pump operation signal, and a water quality signal.

22. System according to claim 19, wherein

said dosing location (182) is at an upstream point in a sewer conduit with respect to said monitoring location (270).

23. System according to claim 19, wherein

said monitoring location (270) comprises a manhole in said sewer network.

24. System according to claim 19, wherein

said detrimental substance is a reduced organic substance.

25. System according to claim 24, wherein

said detrimental substance is a reduced sulphuric compound.

26. System according to claim 25, wherein

said detrimental substance H₂S, and

said additive is a nitrate-based H₂S controlling substance.

27. System according to claim 19, wherein said monitoring device (200) comprises:

an internal bus (210), interconnecting

a processor (230), a memory (220), an input adapter (240) and an RF transmitter (250),

said input adapter (240) being connected to a sensor (260) for providing said measured concentration.

28. System according to claim 19, wherein said dosing controller (100) comprises:

an internal bus (110), interconnecting

a processor (130), a memory (120), an output adapter (140) and an RF receiver (150), said output adapter (140) being connected to said dosing device (160).

29. System according to claim 28, wherein said dosing controller further comprises:

an input adapter (180) connected to a critical process indicator input device (190) at the dosing location, said input device being selected from a group comprising a flow meter, a temperature sensor, a sewage pump control system, and a water quality sensor.

30. System according to claim 19,

further comprising a radio frequency repeater (310) arranged above ground between said monitoring device (200) and said dosing controller (100).

31. System according to claim 19,

further comprising a main controller (400), operatively connected to said dosing controller (100) via a communication network (410), said main controller being arranged to perform at least one of the following steps:

coordinating the overall balance of chemical dosing in the sewer network, and

in the event of a failure in a dosing controller, to re-distribute the control task of the failed dosing controller to another dosing controller.

32. System according to claim 19, wherein said dosing controller (100) is arranged for calculating said dose of said additive based on said derived concentration signal by means of a regular feedback control method, such as a PI or PID control method.

33. System according to claim 32,

wherein said dosing controller (100) is further arranged for calculating said dose of said additive based on historical concentration signal data, including concentration signal values measured at the same time on a previous day.

34. A dosing controller (100) for use in a system for controlling the concentration of a detrimental substance in a sewer network, the system comprising a monitoring device (200), arranged for

providing a signal indicating a measured concentration of said detrimental substance at a monitoring location (270) in said sewer network, and

transmitting a signal carrying information about said concentration, the dosing controller (100) being arranged for

receiving said signal carrying information about said concentration,

deriving a concentration signal based on said received signal,

calculating a dose of an additive based on said derived concentration signal, said additive being selected in order to counterbalance the effect of the detrimental substance, and

supplying a dosing signal to a dosing device (160), causing the dosing device (160) to add said calculated dose at a dosing location (182) in said sewer network, wherein

said monitoring device comprises a time controlled radio frequency transmitter adapted to transmit said signal carrying information about said concentration as a radio frequency signal, the radio frequency transmitter being activated

at regular time intervals or

whenever the concentration indicating signal has changed, with an adjustable threshold for trigging transmission.

35. Dosing controller according to claim 34,

the dosing controller (100) being further arranged for calculating said dose of said additive based on said derived concentration signal by means of a regular feedback control method, such as a PI or PID control method.

36. Dosing controller according to claim 35,

the dosing controller (100) being further arranged for calculating said dose of said additive based on historical concentration signal data, including concentration signal values measured at the same time on a previous day.