IL223080A

IL223080A - Method for treating water in steam boilers

Info

Publication number: IL223080A
Application number: IL223080A
Authority: IL
Inventors: Sherzer David
Original assignee: Sherzer David
Priority date: 2012-11-15
Filing date: 2012-11-15
Publication date: 2017-01-31
Also published as: WO2014076670A1; BR112015010901A2

Description

Method for Treating Water in Steam Boilers Method for Treating Water in Steam Boilers The present invention relates to methods for water treatment in steam boilers, 5 and more specifically a chemicals-free method for substantially reducing sedimentation of solids and minerals in the boiler and for reducing corrosion processes in the boiler. 10 BACKGROUND Steam boilers use heat to convert water to steam. It is known in the art that, in steam boilers, undesired scale products are generated in the boiler 2 itself, see Figs. 1 and 2. Furthermore, accelerated corrosion may occur. 15 Prior art methods for water treatment deal with three major problems in order to avoid or reduce the above-mentioned problems: 1. Scale formation and sedimentation is avoided by removing, from the feed water 12, the hard minerals by softeners 42 or by removing the minerals by using RO systems. 20 2. The corrosion inhibiting is currently handled by pre-heating the feed water and extracting by heat the dissolved gases such as Oxygen and C02 prior to feeding the water into the boiler. 3. Additionally, adding anti-corrosion chemicals in order to inhibit the corrosion processes. 25 Figs. 1 and 2 illustrate a system including a steam boiler 2 containing part water 21 and part steam 22. There is a water inlet 12 and a steam outlet 23. Furthermore, Fig. 2 illustrates a system including such water treatment means as a filter 41, water softener 42, deaerator 45 and condense 46, 30 as well as salt in 43 and brine out 44.

Water in boilers 2 which evaporate water into steam should be treated so as to rediice scale formation in the boiler from the remaining water, as well as to inhibit corrosion process in the boiler. The natural tendency of water at high temperatures is to form scale and corrosion products in the boiler.

The traditional methods for fighting scale and corrosion using soft water or RO water is designed to address the scale deposits problems and the 5 chemicals addition is targeted to inhibit corrosion.

Possible problems with the abovedetailed traditional technologies: 1. Using soft water as a solution to scale problems creates corrosion problems (reddish water). 10 2. Using soft water creates waste water problems due to the fact that the softener is regenerated with a high concentration of salt 44. This salt must be disposed properly and cannot be poured into to the normal sewage system. 15 3. The chemicals 43 used to inhibit the scale and corrosion formation are released into the waste water and may have an undesirable effect on the environment. 20 4. Softeners and chemicals require operating and maintenance attention as well as logistic and handling - a waste of time and money.

SUMMARY OF THE INVENTION 25 According to one aspect of the present invention, raw water is used instead of chemicals as a source for anti-corrosion inhibitors. Raw water is used in order to pre-treat only about 60% of the water. The rest, or 40% of the water, will be regular raw water leaving the Calcium in the water to be a natural corrosion 30 inhibitor.

The excess of Calcium in the raw water that can potentially form scale will cause a scale deposit in a specifically designed reactor (the UET reactor).

Thus, scale will be deposited in the UET reactor rather than in the boiler.

It is much easier to clean scale from the UET reactor than from the boiler. According to another feature of the present invention, scale precipitation in the UET reactor is stimulated using a partial electrolysis.

Furthermore, partial "hard" water will be introduced into the boiler; such water as can be used in the boiler feed without any need for softening the 5 water or introducing chemicals and while ameliorating the problems of scale or corrosion problems. The water in the boiler system will remain balanced and therefore scale or corrosion problems are reduced.

This process eliminates the need for chemical introduction.

According to yet another aspect of the invention, water is recycled between the 10 heater and the UET reactor, to accelerate the precipitation of scale, to prepare the water for use in the boiler.

Furthermore, water is recycled through the UET reactor at a faster rate (volume of water per hour) than the rate water is converted to steam in the boiler. 15 LIST OF DRAWINGS Fig. 1 illustrates, by way of example, a prior art steam boiler application. 20 Fig. 2 illustrates a prior art water treatment method in a steam boiler.

Fig. 3 illustrates a system apparatus using the present invention. 25 Fig. 4 illustrates the UET reactor(TM).

Fig. 5 illustrates the new water treatment method in a steam boiler.

DETAILED DESCRIPTION OF THE INVENTION The current invention will now be described by way of example and with reference to the accompanying drawings. 5 Figs. 1 and 2 illustrate prior art systems as abovedetailed.

Fig. 3 illustrates an apparatus using the present invention. Water fed into the system through a water inlet 12 is heated in a hot water tank 1, then transferred to a steam boiler 2 through a feed pump 31. 10 As illustrated, the boiler 2 contains part water 21 and part steam 22.

The steam exits the system through a steam outlet 23.

For example, in a steam generating system, the water in may flow at a rate of 5 cubic meter per hour through inlet 12; the system output may be about 5 ton per hour of steam, out of outlet 23. 15 In addition to this prior art path of evaporating water into steam, there is a novel path for recirculating water, from the hot water tank 1 through the recirculation pump 32 and UET reactor 33, back into the tank 1.

In an exemplary system as detailed above, water may be recirculated 20 at the rate of 50 cubic meters per hour. Preferably, in the recirculation path water moves at a faster rate than in the normal evaporation path.

This accelerated rate of recirculation causes scale deposits at a faster rate in the UET reactor, to efficiently clean the water to be transferred to the boiler 2. Thus, with scale being deposited in reactor 33, the amount of scale 25 deposited in the boiler is greatly reduced.

Thus, raw water is used as a source for anti-corrosion inhibitors; preferably, raw water is used to pre-treat only about 60% of the water. The rest, or 40% of the water, will be regular raw water transferred to the 30 boiler 2, leaving Calcium in the water to be a natural corrosion inhibitor.

The excess of Calcium in the raw water, that can potentially form scale, will cause a scale deposit in a specifically designed reactor 33 (the UET reactor).

Thus, scale will be deposited in the UET reactor 33 rather than in the boiler 2.