Diluting system and method

• US 6,845,298 B2
• Filed: 08/27/2002
• Issued: 01/18/2005
• Est. Priority Date: 08/31/2001
• Status: Expired due to Fees

• Current Assignee: Force Flow
• Original Assignee: Force Flow
• Inventors: Nelson, Mark, Davidson, Brad, Townsend, Mike
• Primary Examiner(s): Picard, Leo
• Assistant Examiner(s): RODRIGUEZ, PAUL L
• Application Number:
  US10/230,076
• Publication Number:
  US 20030050736A1
• Time in Patent Office: 875 Days
• Field of Search: 700/67, 700/68, 700/80, 700/239, 700/265, 700/281, 700/282, 700/285, 700/305, 137/403, 366/132, 366/140, 366/141, 702/50, 702/55
• US Class Current: 700/265
• CPC Class Codes: B01F 23/483 using water for diluting a liquid ingredient, obtaining a predetermined concentration or making an aqueous solution of a concentrate
• CPC Class Codes: B01F 23/49 Mixing systems, i.e. flow charts or diagrams
• CPC Class Codes: B01F 35/21 Measuring
• CPC Class Codes: B01F 35/2111 Flow rate
• CPC Class Codes: B01F 35/2117 Weight
• CPC Class Codes: B01F 35/2132 Concentration, pH, pOH, p(ION) or oxygen-demand B01F35/2133 takes precedence
• CPC Class Codes: B01F 35/2211 Amount of delivered fluid during a period
• CPC Class Codes: B01F 35/88 by feeding the materials batchwise
• CPC Class Codes: B01F 35/883 using flow rate controls for feeding the substances
• CPC Class Codes: G05D 21/02 characterised by the use of electric means

Abstract

A system and a method for automatically, accurately diluting chemical solutions on an industrial scale based upon real time weight measurements of chemical and diluent weight is disclosed.

Claims

1. A dilution system for a chemical comprising:

a dilution tank of known capacity for preparing the chemical in a desired diluted concentration, the tank mounted upon an electronic scale, the scale being capable of generating a series of weight signals related to the weight of the tank when empty and at various levels of filling;

a source of liquid concentrated chemical feed having a first, but variable, concentrated chemical concentration;

a chemical feed flow controller for controlling the flow of concentrated chemical feed to the dilution tank;

a source of liquid diluent;

a diluent flow controller for controlling the flow of diluent to the dilution tank;

a system controller;

for receiving;

(a) a value related to the dilution tank capacity;

(b) a value related to the variable, concentrated chemical concentration;

(c) a value related to the desired diluted concentration; and

(d) a series of weight signals from the scale;

for calculating the amounts of concentrated chemical and diluent required to provide a target amount of diluted chemical of desired diluted concentration which does not exceed the known capacity of the dilution tank;

for controlling the chemical feed flow controller and the diluent flow controller based upon the series of weight signals to produce a produced quantity of diluted chemical, the produced quantity related to the target amount of diluted chemical and not exceeding the capacity of the dilution; and

wherein the chemical undergoes degradation over time and the value related to the variable concentrated chemical concentration is a value usable by the system controller to calculate a concentrated chemical concentration value.

2. The dilution system of claim 1, additionally comprising a working tank in liquid communication with the dilution tank and into which the diluted chemical can be passed.

3. The dilution system of claim 2, additionally comprising at least one vent line in outlet liquid communication with said working tank.

4. The dilution system of claim 3, additionally comprising a check valve and a flow switch wherein said flow switch is able to shut down the system if flow is detected in said vent lines.

5. The dilution system of claim 1, wherein the value related to the variable concentrated chemical concentration is a concentrated chemical concentration.

6. The dilution system of claim 1, additionally comprising a readable memory into which weight signals are stored, said weight signals being from the series of weight signals related to at least one of:

the target amount of diluted chemical produced by the dilution system;

a weight of chemical present in the target amount of diluted chemical produced by the dilution system; and

a weight of diluent present in the target amount of diluted chemical produced by the dilution system.

7. The dilution system of claim 6, additionally comprising a chamber of known volume in inlet liquid communication with the source of concentrated chemical feed and in outlet liquid communication with said dilution tank for adding a known volume of concentrated chemical feed to the dilution tank.

8. The dilution system of claim 7, said chamber additionally comprising an overflow line, said overflow line in outlet liquid communication with said chamber and inlet liquid communication with said source of concentrated chemical feed.

9. The dilution system of claim 7, said chamber additionally comprising an overflow line, said overflow line in outlet liquid communication with said chamber and inlet liquid communication with said source of dilution tank.

10. The dilution system of claim 1, additionally comprising a slow neat chemical transfer alarm which compares a weight of concentrated chemical measured by the scale with a minimum weight value and triggers an alarm if the measured weight is less than the minimum value.

11. The dilution system of claim 1, additionally comprising a slow diluent transfer alarm which compares a weight of diluent measured by the scale with a minimum weight value and triggers an alarm if the measured weight is less than the minimum value.

12. The dilution system of claim 1, additionally comprising a slow dilute chemical feed alarm which compares a weight of dilute chemical measured by the scale with a maximum weight value and triggers an alarm if the measured weight is greater than the maximum value.

13. The dilution system of claim 1, additionally comprising a maximum chemical usage alarm which compares a weight of dilute chemical measured by the scale with a minimum weight value and triggers an alarm if the measured weight is less than the minimum value.

14. The dilution system of claim 1, additionally comprising a dilution tank high level alarm which compares the weight of material in the dilution tank, as measured by the scale with a maximum value related to the capacity of the dilution tank and triggers an alarm if the measured value is equal to or exceed the maximum value and the desired dilution concentration had not been achieved.

15. The dilution system of claim 1, additionally comprising a batch strength not available alarm which compares a measured weight of chemical or diluent and based upon a target dilution value triggers an alarm if dilution of the measured weight to the target dilution value will result in overfilling the dilution tank before the target dilution is obtained.

16. The dilution system of claim 1, additionally comprising:

(a) a slow neat chemical transfer alarm which compares a weight of concentrated chemical measured by the scale with a minimum weight value and triggers an alarm if the measured weight is less than the minimum value;

(b) a slow diluent transfer alarm which compares a weight of diluent measured by the scale with a minimum weight value and triggers an alarm if the measured weight is less than the minimum value;

(c) a slow dilute chemical feed alarm which compares a weight of dilute chemical measured by the scale with a maximum weight value and triggers an alarm if the measured weight is greater than the maximum value;

(d) a maximum chemical usage alarm which compares a weight of dilute chemical measured by the scale with a minimum weight value and triggers an alarm if the measured weight is less than the minimum value;

(e) a dilution tank high level alarm which compares the weight of material in the dilution tank, as measured by the scale with a maximum value related to the capacity of the dilution tank and triggers an alarm if the measured value is equal to or exceed the maximum value and the desired dilution concentration had not been achieved; and

(f) a batch strength not available alarm which compares a measured weight of chemical or diluent and based upon a target dilution value triggers an alarm if the measured weight and the target dilution value will result in overfilling the dilution tank before the target dilution is obtained.

17. The dilution system of claim 1, additionally comprising at least one vent line in outlet liquid communication with said dilution tank.

18. The dilution system of claim 17, additionally comprising a check valve and a flow switch wherein said flow switch is able to shut down the system if flow is detected in said vent lines.

19. The dilution system of claim 1, additionally comprising a pump for feeding diluted chemical to a source of water wherein said system controller receives a value related to a speed of said pump and calculates the amounts of concentrated chemical and diluent required to provide a target amount of diluted chemical of desired diluted concentration for operating said pump at an optimum efficiency.

20. The dilution system of claim 1, additionally comprising:

a chemical supply tank of known capacity having a source of liquid concentrated chemical feed, the chemical supply tank mounted upon a feed tank scale, the feed tank scale being capable of generating a series of weight signals related to the weight of the tank when empty and at various levels of filing;

a plurality of level sensors located inside the chemical supply tank, the level sensors being capable of generating a series of level signals related to the level of the chemical supply tank at various levels of filing; and

wherein the system controller calculates and displays an amount of concentrated chemical feed in a weight equivalent.

21. The dilution system of claim 1, wherein the chemical is sodium hypochlorite and the diluent is water.

22. A dilution control system for aqueous sodium hypochlorite comprising:

a dilution tank of known capacity for preparing the sodium hypochlorite in a desired diluted concentration, the tank mounted upon an electronic scale, the scale being capable of generating a series of weight signals related to the weight of the tank when empty and at various levels of filling;

a source of liquid concentrated sodium hypochlorite feed having a first, but variable, concentrated sodium hypochlorite concentration;

a sodium hypochlorite feed flow controller for controlling the flow of concentrated sodium hypochlorite feed to the dilution tank;

a source of water;

a water flow controller for controlling the flow of water to the dilution tank; and

a system controller;

for receiving;

(a) a value related to the dilution tank capacity;

(b) a value related to the variable, concentrated sodium hypochlorite concentration;

(c) a value related to the desired diluted sodium hypochlorite concentration; and

(d) a series of weight signals from the scale;

for calculating the amounts of concentrated sodium hypochlorite and water required to provide a target amount of diluted sodium hypochlorite of desired diluted concentration which does not exceed the known capacity of the dilution tank; and

for controlling the sodium hypochlorite feed flow controller and the water flow controller based upon the series of weight signals to produce a produced quantity of diluted sodium hypochlorite, the produced quantity related to the target amount of diluted sodium hypochlorite and not exceeding the capacity of the dilution tank; and

wherein the chemical undergoes degradation over time and the value related to the variable concentrated chemical concentration is a value usable by the system controller to calculate a concentrated chemical concentration value.

23. A method for diluting a chemical to a desired dilution comprising the steps of:

(a) obtaining a dilution control system comprising;

a dilution tank of known capacity for preparing the chemical in a desired diluted concentration, the tank mounted upon an electronic scale, the scale being capable of generating a series of weight signals related to the weight of the tank when empty and at various levels of filling;

a source of liquid concentrated chemical feed having a first, but variable, concentrated chemical concentration;

a chemical feed flow controller for controlling the flow of concentrated chemical feed to the dilution tank;

a source of liquid diluent;

a diluent flow controller for controlling the flow of diluent to the dilution tank; and

a system controller;

for receiving;

(i) a value related to the dilution tank capacity;

(ii) a value related to the variable, concentrated chemical concentration;

(iii) a value related to the desired diluted concentration; and

(iv) a series of weight signals from the scale;

for calculating the amounts of concentrated chemical feed and diluent required to provide a target amount of diluted chemical of desired diluted concentration which does not exceed the known capacity of the dilution tank; and

for controlling the chemical feed flow controller and the diluent flow controller based upon the series of weight signals to produce a produced quantity of diluted chemical, the produced quantity related to the target amount of diluted chemical and not exceeding the capacity of the dilution tank;

(b) inputting into the system controller;

(i) the value related to the dilution tank capacity;

(ii) the value related to the variable, concentrated chemical feed concentration; and

(iii) the value related to the desired diluted concentration;

(c) calculating in the system controller the amount of concentrated chemical feed required to provide a target amount of diluted chemical of desired diluted concentration which does not exceed the dilution tank capacity;

(d) charging to the dilution tank the amount of concentrated chemical feed calculated in step (c), the amount charged being controlled by the chemical feed flow controller and the system controller based upon a series of weight values generated by the scale during the charging, wherein the series of weight values of concentrated chemical feed concentration are transmitted to the system controller;

(e) calculating in the system controller the amount of diluent required to provide a target amount of diluted chemical of desired diluted concentration which does not exceed the dilution tank capacity;

(f) charging to the dilution tank the amount of diluent calculated in step (e), the amount charged being controlled by the diluent feed flow controller and the system controller based upon a series of weight values generated by the scale during the charging, wherein the series of weight values of diluent are transmitted to the system controller; and

(g) feeding diluted chemical from a working tank via a working tank pump to a source of water wherein said system controller receives a value related to a speed of said pump and calculates the amounts of concentrated chemical and diluent required to provide a target amount of diluted chemical of desired diluted concentration for operating said pump at an optimum efficiency.

24. The method of claim 23, wherein the value related to the variables concentrated chemical concentration is a value related to the weight of a measured known volume of concentrated chemical feed.

25. The method of claim 24, wherein the value related to the weight of a measured known volume of concentrated chemical feed is generated by the scale.

26. The method of claim 23, additionally comprising:

a chemical supply tank of known capacity having a source of liquid concentrated chemical feed, the chemical supply tank mounted upon a feed tank scale, the feed tank scale being capable of generating a series of weight signals related to the weight of the chemical supply tank when empty and at various levels of filing;

a plurality of level sensors located inside the chemical supply tank, the level sensors being capable of generating a series of level signals related to the level of the chemical supply tank at various levels of filing; and

wherein the system controller calculates and displays an amount of concentrated chemical feed in a weight equivalent.

27. The method of claim 23, wherein the chemical is sodium hypochlorite and the diluent is water.

28. The method of claim 23, wherein the chemical is sodium hypochlorite and the diluent is water.

29. A system for adjusting a flow of diluted chemical comprising:

a tank of known capacity for preparing a chemical in a desired diluted concentration, the tank mounted upon an electronic scale, the scale being capable of generating a series of weight signals related to the weight of the tank when empty and at various levels of filling;

a source of liquid concentrated chemical feed having a first, but variable, concentrated chemical concentration;

a chemical feed flow controller for controlling the flow of concentrated chemical feed to the tank;

a source of liquid diluent;

a diluent flow controller for controlling the flow of diluent to the tank;

a pump for feeding a diluted concentration to a water system from the tank, the pump being capable of generating a series of signals related to an amount of diluted concentration being fed to the water system; and

a system controller;

(a) for receiving;

(i) a value related to the tank capacity;

(ii) a value related to the variable, concentrated chemical concentration;

(iii) a value related to the desired diluted concentration;

(iv) a series of weight signals from the scale; and

(v) a series of signals from the pump;

(b) for calculating the amount of diluted concentration being fed to the water system and a pump speed;

(c) for calculating the amounts of concentrated chemical feed and diluent required to provide a target amount of diluted chemical of desired diluted concentration which does not exceed the known capacity of the tank wherein said pump speed is within a defined range; and

(d) for controlling the chemical feed flow controller and the diluent flow controller based upon the series of weight signals to produce a produced quantity of diluted chemical, the produced quantity related to the target amount of diluted chemical and not exceeding the capacity of the tank.

30. The system of claim 29, wherein the system controller automatically adjusts the target amount of diluted chemical of desired diluted concentration being fed to the water system based on the pump speed.

31. A method for adjusting a flow of diluted chemical comprising:

a tank of known capacity for preparing a chemical in a desired diluted concentration, the tank mounted upon an electronic scale, the scale being capable of generating a series of weight signals related to the weight of the tank when empty and at various levels of filling;

a source of liquid concentrated chemical feed having a first, but variable, concentrated chemical concentration;

a chemical feed flow controller for controlling the flow of concentrated chemical feed to the tank;

a source of liquid diluent;

a diluent flow controller for controlling the flow of diluent to the tank;

a pump for feeding diluted concentration to a water system from the tank, the pump being capable of generating a series of signals related to an amount of diluted concentration being fed to the water system; and

a system controller;

(a) for receiving;

(i) a value related to the tank capacity;

(ii) a value related to the variable, concentrated chemical concentration;

(iii) a value related to the desired diluted concentration;

(iv) a series of weight signals from the scale; and

(v) a series of signals from the pump;

(b) for calculating the amount of diluted concentration being fed to the water system and a pump speed;

(c) for calculating amounts of concentrated chemical feed and diluent required to provide a target amount of diluted chemical of desired diluted concentration which does not exceed the known capacity of the tank wherein said pump speed is within a defined range; and

(d) for controlling the chemical feed flow controller and the diluent flow controller based upon the series of weight signals to produce a produced quantity of diluted chemical, the produced quantity related to the target amount of diluted chemical and not exceeding the capacity of the tank.

32. The method of claim 31, wherein the system controller automatically adjusts the target amount of diluted chemical of desired diluted concentration being fed to the water system based on the pump speed.

33. A system for preparing a chemical in a desired diluted concentration comprising:

a tank of known capacity for preparing a chemical in a desired diluted concentration, the tank mounted upon an electronic scale, the scale being capable of generating a series of weight signals related to the weight of the tank when empty and at various levels of filling;

a source of liquid concentrated chemical feed having a first, but variable, concentrated chemical concentration;

a chemical feed flow controller for controlling the flow of concentrated chemical feed to the tank;

a source of liquid diluent;

a diluent flow controller for controlling the flow of diluent to the tank;

a pump for feeding the chemical in a desired diluted concentration to a water system from the tank; and

a system controller;

(a) for receiving;

(i) a value related to the tank capacity;

(ii) a value related to the variable, concentrated chemical concentration;

(iii) a value related to the desired diluted concentration;

(iv) a series of weight signals from the scale; and

(v) a series of signals from the water system as to an amount of water in the water system;

(b) for calculating the desired diluted concentration based on the amount of water in the water system;

(c) for calculating amounts of concentrated chemical feed and diluent required to provide a target amount of diluted chemical of desired diluted concentration which does not exceed the known capacity of the tank; and

(d) for controlling the chemical feed flow controller and the diluent flow controller based upon the series of weight signals to produce a produced quantity of diluted chemical, the produced quantity related to the target amount of diluted chemical and not exceeding the capacity of the tank.

34. The system of claim 33, wherein the system controller automatically adjusts the desired diluted concentration based on the amount of water in the water system.

35. A method for preparing a chemical in a desired diluted concentration comprising:

a tank of known capacity for preparing a chemical in a desired diluted concentration, the tank mounted upon an electronic scale, the scale being capable of generating a series of weight signals related to the weight of the tank when empty and at various levels of filling;

a source of liquid concentrated chemical feed having a first, but variable, concentrated chemical concentration;

a chemical feed flow controller for controlling the flow of concentrated chemical feed to the tank;

a source of liquid diluent;

a diluent flow controller for controlling the flow of diluent to the tank;

a pump for feeding the chemical in a desired diluted concentration to a water system from the tank; and

a system controller;

(a) for receiving;

(i) a value related to the tank capacity;

(ii) a value related to the variable, concentrated chemical concentration;

(iii) a value related to the desired diluted concentration;

(iv) a series of weight signals from the scale; and

(v) a series of signals from the water system as to an amount of water in the water system;

(b) for calculating the desired diluted concentration based on the amount of water in the water system;

(c) for calculating the amounts of concentrated chemical feed and diluent required to provide a target amount of diluted chemical of desired diluted concentration which does not exceed the known capacity of the tank; and

(d) for controlling the chemical feed flow controller and the diluent flow controller based upon the series of weight signals to produce a produced quantity of diluted chemical, the produced quantity related to the target amount of diluted chemical and not exceeding the capacity of the tank.

36. The method of claim 35, wherein the system controller automatically adjusts the desired diluted concentration based on the amount of water in the water system.

37. A dilution system for a chemical comprising:

a dilution tank of known capacity for preparing the chemical in a desired diluted concentration, the tank mounted upon an electronic scale, the scale being capable of generating a series of weight signals related to the weight of the tank when empty and at various levels of filling;

a source of liquid concentrated chemical feed having a first, but variable, concentrated chemical concentration;

a chemical feed flow controller for controlling the flow of concentrated chemical feed to the dilution tank;

a source of liquid diluent;

a diluent flow controller for controlling the flow of diluent to the dilution tank;

a system controller;

for receiving;

(a) a value related to the dilution tank capacity;

(b) a value related to the variable, concentrated chemical concentration;

(c) a value related to the desired diluted concentration; and

(d) a series of weight signals from the scale;

for calculating the amounts of concentrated chemical and diluent required to provide a target amount of diluted chemical of desired diluted concentration which does not exceed the known capacity of the dilution tank; and

for controlling the chemical feed flow controller and the diluent flow controller based upon the series of weight signals to produce a produced quantity of diluted chemical, the produced quantity related to the target amount of diluted chemical and not exceeding the capacity of the dilution tank;

a readable memory into which weight signals are stored, said weight signals being from the series of weight signals related to at least one of;

the target amount of diluted chemical produced by the dilution system;

a weight of chemical present in the target amount of diluted chemical produced by the dilution system; and

a weight of diluent present in the target amount of diluted chemical produced by the dilution system; and

a chamber of known volume in inlet liquid communication with the source of concentrated chemical feed and in outlet liquid communication with said dilution tank for adding a known volume of concentrated chemical feed to the dilution tank.

38. The dilution system of claim 37, said chamber additionally comprising an overflow line, said overflow line in outlet liquid communication with said chamber and inlet liquid communication with said source of concentrated chemical feed.

39. The dilution system of claim 37, said chamber additionally comprising an overflow line, said overflow line in outlet liquid communication with said chamber and inlet liquid communication with said source of dilution tank.

40. A system for diluting a chemical for water treatment comprising:

a dilution tank of known capacity for preparing the chemical in a desired diluted concentration, the tank mounted upon an electronic scale, the scale being capable of generating a series of weight signals related to the weight of the tank when empty and at various levels of filling;

a source of liquid concentrated chemical feed having a first, but variable, concentrated chemical concentration;

a chemical feed flow controller for controlling the flow of concentrated chemical feed to the dilution tank;

a source of liquid diluent;

a diluent flow controller for controlling the flow of diluent to the dilution tank;

a system controller;

for receiving;

(a) a value related to the dilution tank capacity;

(b) a value related to the level of the tank at various levels of filing;

(c) a value related to the variable, concentrated chemical concentration;

(d) a value related to the desired diluted concentration; and

(e) a series of weight signals from the scale, wherein the series of weights signals are actual weights of concentrated chemical concentration and diluent;

for calculating the amounts of concentrated chemical and diluent required to provide a target amount of diluted chemical of desired diluted concentration which does not exceed the known capacity of the dilution tank;

for adjusting the amount of concentrated chemical or diluent required to provide the target amount of diluted chemical of desired concentration based on the actual weights of concentrated chemical concentration and diluent within the dilution tank;

for controlling the chemical feed flow controller and the diluent flow controller based upon the series of weight signals to produce a produced quantity of diluted chemical, the produced quantity related to the target amount of diluted chemical and not exceeding the capacity of the dilution tank; and

a pump for feeding diluted chemical to a source of water wherein said system controller receives a value related to a speed of said pump and calculates the amounts of concentrated chemical and diluent required to provide a target amount of diluted chemical of desired diluted concentration for operating said pump at an optimum efficiency.

41. The dilution system of claim 40, additionally comprising a working tank in liquid communication with the dilution tank and into which the diluted chemical can be passed.

42. The dilution system of claim 41, additionally comprising at least one vent line in outlet liquid communication with said working tank.

43. The dilution system of claim 42, additionally comprising a check valve and a flow switch wherein said flow switch is able to shut down the system if flow is detected in said vent lines.

44. The dilution system of claim 40, wherein the value related to the variable concentrated chemical concentration is a concentrated chemical concentration.

45. The dilution system of claim 40, additionally comprising at least one vent line in outlet liquid communication with said dilution tank.

46. The dilution system of claim 45, additionally comprising a check valve and a flow switch wherein said flow switch is able to shut down the system if flow is detected in said vent lines.