CA2675338A1

CA2675338A1 - Use of blow down water in a cooling tower

Info

Publication number: CA2675338A1
Application number: CA2675338A
Authority: CA
Inventors: Claude L. Hebert
Original assignee: Individual
Current assignee: Individual
Priority date: 2009-08-12
Filing date: 2009-08-12
Publication date: 2011-02-12
Also published as: CA2712708A1; US20120036867A1

Description

USE OF BLOW DOWN WATER IN A COOLING TOWER
FIELD OF THE INVENTION

The present invention relates to a method and more particularly, relates to a method of irrigation.

BACKGROUND OF THE INVENTION

Catalytic water treatment for cooling towers and evaporative condensers are known in the art. These systems are generally used in closed loop arrangements wherein they prevent scaling and can be used even for removal of scale.

These devices use magnetic treatment means which generate magnetic lines of flux wherein water is directed in a spiral fashion such that it is subject to the magnetic lines of flux at an angle along with the filters arranged to filter the fluid passing through the magnetic treatment means.

The water is usually relatively high concentration of calcium. Periodically, the cooling towers must be blown down. Conventionally, the blow down liquid is dumped to the sewer system.

SUMMARY OF THE INVENTION

According to the present invention, the water from the blow down is utilized for irrigation in lieu of dumping it to the sewer system.

The irrigation water is preferably utilized in close proximity to the cooling towers. In many operations, greenery is growing nearby. This can range from rooftop greenery to greenery or shrubbery on the grounds.

The soil needs substantial quantities of calcium in order to grow healthy and fruit-bearing plants. Calcium plays a role in the fertility of the soil by reducing its acidity.
This is well known in the art and frequently calcium is added to the soil in the form of limestone or calcium carbonate.

Finely ground lime is conventionally used as it is easily absorbed by the soil and reacts readily with other substances to produce top results.

When the water in the cooling tower is subjected to a catalytic treatment, the blow off is typically less than M. The bleed off water is concentrated with minerals such as calcium, magnesium and iron which can be used as nutrients for grass and plants. A 400 ton cooling tower normally circulates at approximately 1200 gpm with the bleed off being 12 gpm which is equal to approximately 17,000 gallons of water per day.
BRIEF DESCRIPTION OF THE DRAWINGS

An example of a catalyser utilized in the treatment of industrial water is shown wherein:

Figure 1 is a schematic view of a system according to one embodiment; and Figures 2 to 5 are schematic views of other types of systems.

DETAILED DESCRIPTION OF THE INVENTION

Referring to the drawings in greater detail and by reference characters thereto, there is illustrated a treatment system such as may be used in the present invention. The system is designed to be used with a closed circuit heat exchanger which includes a pipe 10 having fluid circulating in the direction indicated by arrow 12.

The system will include a conduit 14 which is tapped into pipe 10 such that a certain portion of the water within the heat transfer circulation will be diverted thereto. Preferably, the amount is between 5 and 15 percent and even more preferably between 8 and 10 percent of the total flow.

Conduit 14 includes a valve 16 thereon and there may be provided a pump on the

-2-line, depending upon the desired pressures.

A system inlet 20 has a bypass conduit 22 located thereat. On bypass conduit there are provided pressure gages 24 and 25 with a valve 26 therebetween.

Treatment line 28 has a valve 30 thereon. A filter 32 having the desired filtering media therein filters the water to be treated. From filter 32, there is provided a conduit 34.
On conduit 34, there is provided a discharge line 36 and associated valve 38.
A magnetic treatment device 40 is of the type shown in United States Patent Number 5,149,438, the teachings of which are hereby incorporated by reference. After magnetic treatment device 40, there is also provided a discharge line 42 with associated valve 44. On conduit 45, there is provided a valve 46 and this is connected to a return line 48 feeding back into main pipe 10.

During the process iron oxide is picked up within the magnetic treatment device and retained therein. These iron oxide particles can be removed through discharge line 42 when required.

Figures 2 to 5 illustrate other arrangements which may be utilized. It is believed that the circuits are self-explanatory with reference numeral 52 designating the pipe through which the liquid is circulated and from where the liquid to be treated is taken. Reference numeral 54 designates the magnetic treatment unit while reference numeral 56 is utilized for gauges. The ball valves are designated by reference numeral 58 while cartridge filters are designated by reference numeral 60. As an alternative to cartridge filters 60, bag filters 62 may be employed. Reference number 66 designates a manifold which may be utilized in cases of limited space.

In the above arrangement, the water being treated will be rich in potential nutrients

-3-for plants and the blow down from the tower may be utilized for irrigation.

It will be understood that the above described embodiment is for purposes of illustration only and that changes and modifications may be made thereto without departing from the spirit and scope of the invention.

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