JPH07171560A - Activated carbon filter device and method for removing hydrogen peroxide from fluid - Google Patents

Abstract

PURPOSE: To remove hydrogen peroxide from a fluid containing hydrogen peroxide by bringing the fluid successively into contact with a gravel layer and an activated carbon layer.

CONSTITUTION: A waste liquid containing hydrogen peroxide enters an entrance means 18 through a valve 62 and ascends through a main inlet conduit 20 to the bottom 3 of a filter F. Then the fluid enters a gravel layer 8 (acid-resistant high silica sand), permeates through gravel layers 10, 12, 14 and moves into the filter F. When the fluid reaches the activated carbon layer 16, the fluid with oxygen gas released along the passage passes through the activated carbon layer 16 for filtration. The oxygen gas with the fluid without peroxide is reserved in an upper reservoir 45. The fluid thus treated and collected in the reservoir 45 passes through a polypropylene cloth filter 42, passes through a main outlet conduit 26 and enters a reservoir 78. Thereby, hydrogen peroxide can be removed from the fluid containing hydrogen peroxide.

COPYRIGHT: (C)1995,JPO

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to an apparatus and method for removing hydrogen peroxide from a fluid by passing the fluid through an activated carbon filter device. More specifically, the present invention relates to the removal of hydrogen peroxide from an electroplating waste liquid produced in an iron-based plating process.

[0002]

It is well known in the industry that the surface of iron or steel is easily corroded. A metal coating of nickel or zinc, or a mixture thereof, is often applied to the surface to protect them from the progress of corrosion. Zinc and nickel have been electroplated onto iron or steel substrates with various plating solutions, preferably acid plating solutions, to protect their surfaces for various industrial uses.

One such electroplating apparatus is US Pat. 4,84
0,712. It discloses a pair of conductor rolls that direct a steel strip between a pair of plating anodes in a plating solution. The electroplating process uses a zinc sulphate electroplating solution in addition to the sulfuric acid cleaning solution, which causes the stainless steel conductor rolls to be constantly exposed to electrochemical corrosion and mechanical wear. The Steinvicker patent discloses a method of improving the wear life of conductor rolls by using hydrogen peroxide as a passivation film forming agent in the cleaning solution.

In recent years, the electroplating industry has experienced a solid increase in the cost of some metals used in iron and steel based coatings. This is particularly remarkable in the case of nickel. Nickel prices have fluctuated dramatically over the last few years. Large cost fluctuations have led to the development of many means to recover these valuable plated metals from the exhaust for ultimate reuse in electroplating processes.

One of the methods for recovering nickel, zinc, and other plating metals from a plating treatment solution or a cleaning solution is a cleaning solution involving an ion exchange resin that selectively attracts nickel or zinc cations onto the resin. It has the initial processing of. The subsequent acid cleaning step removes the recovered metal from the resin for ultimate reuse of the plating process. The use of ion exchange resins to remove useful metals from electroplating solutions and wash water is disclosed in US Pat.
o. No. 4,783,249, Hayashi US Patent No.
No. 4,009,101, US Patent No. Three
761,381, Sivers et al., US Patent No. Three
681, 210, Haas et al., US Patent No. 3,63
No. 0,892, etc.

[0006]

However, while the use of ion exchange resin systems has significantly improved the recovery efficiency of zinc and nickel from the plating waste stream, it has been used in cleaning solutions to minimize corrosion of the conductor rolls. Hydrogen peroxide added has the opposite effect on the cation exchange resin beads. Applicants have determined that traces of hydrogen peroxide in the waste stream oxidize internal bonds that maintain the resin shape, thereby causing swelling and ultimate depolymerization of the resin. Resin expansion results in a gradual increase in the pressure drop of the ion exchange resin bed, reducing efficiency and ultimately necessitating replacement.

Therefore, there is a need for a technique for removing the hydrogen peroxide passivation film forming agent from the wash solution before the wash solution passes through the ion exchange resin bed. The main object of the present invention is to provide a filter device and method for removing this hydrogen peroxide.

[0008]

A filter device according to the present invention for achieving the above object is an activated carbon filter device for removing hydrogen peroxide from a fluid, the first end being located around a vertical axis. And a second end, a bed of gravel located at the first end of the apparatus, an activated carbon bed located at the second end of the apparatus above the bed of gravel, and first distributing the fluid to be treated. It is characterized by comprising inlet means for contacting the gravel bed and subsequently for contacting the activated carbon bed, and outlet means for receiving the treated fluid emerging from the device.

Also, in the method of removing hydrogen peroxide from a fluid according to the invention, the fluid containing hydrogen peroxide is treated by first contacting the fluid with activated carbon to catalytically destroy the hydrogen peroxide. It The hydrogen peroxide free fluid is then collected for later use.

[0010]

The inlet means distributes the fluid containing hydrogen peroxide to first contact the gravel bed and then the activated carbon bed. The gravel bed filters fine particles contained in the fluid, and the activated carbon bed catalytically decomposes hydrogen peroxide. The decomposition of hydrogen peroxide is carried out quickly and effectively by contacting the high surface area of activated carbon.
Outlet means direct the treated fluid out of the filter device.

[0011]

Embodiments of the present invention will now be described in detail with reference to the drawings. Filter F is shown generally in FIG. 1 and has a housing 2 made of metal or other fluid impermeable material. The housing 2 further has a first end 4 located on the bottom 3 of the filter F and a second end 6 located near the top 5 of the filter F. The first end 4 and the second end 6 are located side by side around the vertical axis of the filter F.

The filter F is generally sized according to the relationship between the flow rate of the fluid being treated and the area within the filter F that receives the flow. In the preferred embodiment, filter F has a height of about 54 inches. The 54 inch filter has a nominal area of 15.9 square feet and operates at about 2.0 gallons / square foot / minute.

Within the first end 4 of the housing 2 is a multi-layered gravel bed 8. The gravel bed 8 assists the introduction of the fluid into the filter F in the distribution process and also serves as a support portion for the activated carbon bed 16 described later. The preferred gravel is a high silica stone that is acid resistant. The gravel bed 8 may be uniform throughout. However, the preferred embodiment of the present invention provides a gravel bed 8 consisting of a succession of individual layers, each containing gravel of different sizes.

As best shown in FIG. 1, coarse gravel is located within the first gravel bed layer 10. This first gravel bed layer 10 comprises 1 / 2x1 / 4 standard mesh stone and has a height of about 10 inches. A second gravel bed layer 12 containing medium sized stones is located on top of the first gravel bed layer 10. This second gravel bed layer 12 has about 3
It has an inch height and contains 1 / 4x1 / 8 standard mesh stone. A third gravel bed layer 14 containing fine stones is located in contact with the top of the second gravel bed layer 12. The third gravel bed layer 14 has a height of about 3 inches and is 1 / 8x1 /
16 standard mesh stones containing fine gravel. In this way, the gravel bed 8 is a continuous grade of concentric gravel bed layers containing gravel of different sizes, each of which gradually becomes coarser to finer stones from the bottom 3 of the housing 2 toward the second end 6. Contains.

An activated carbon bed 16 is provided above the multi-layered gravel bed 8. In the preferred embodiment, the 54 inch filter has an activated carbon bed 16 that is approximately 36 inches high.
The activated carbon used in the filter is of commercial grade,
Acid-cleaned, readily available commercially available activated carbon.
A suitable activated carbon is Calgon Corp.
registered trademark "CPG
It is a product based on bituminous coal sold at "LF". The actual size of the activated carbon particles used in the activated carbon bed 16 is related to peroxide destruction. Applicant is 1
It has been found that 2x40 standard mesh size carbon gives the best peroxide destruction results. Almost complete peroxide destruction using Calgon's "CPG LF" 12x40 mesh activated carbon with plating cleaning solution flow rate of 2.6 gpm (gallons per minute) / square foot or more and inlet peroxide concentration of 1,500 ppm or more. Has been done. However, most commercially available activated carbons can be used in the present invention with good results. Any other brand of activated carbon available on the market is included within the scope of the present invention.

FIG. 4 outlines the effectiveness of hydrogen peroxide destruction using activated carbon according to the present invention. The graph represents the percentage of failure over time in static tests. In this laboratory test, for the duration of the test, about 500 ppm of peroxide was added to the diluted plating solution (20: 1) and heated to about 60 ° C. to 1% of its weight.
/ 10 activated carbon was mixed. At first, there was a sudden generation of oxygen gas. At the end of the test period, the carbon was filtered off and the solution was examined for residual peroxide. The result of the test is shown in FIG.
It can be seen that in 0 minutes about 99% of the peroxide was destroyed.

As mentioned above, the need to remove hydrogen peroxide from the plating solution is most apparent when examining the effect of hydrogen peroxide on cation exchange resins. First 1
5 grams of resin sample each from 1000 ppm to 5
By placing in a series of beakers with a waste aqueous solution of zinc and nickel with a peroxide concentration of ppm, Applicants have tested the performance of Eco-Tec® 3970 cation resin (Echotech, Pickering, Canada). Demonstrate the effect of hydrogen oxide. The resin was equilibrated in a synthesis solution without hydrogen peroxide and then hydrogen peroxide was added to the target concentration. Two methods of evaluation were used to investigate the effect of peroxides on the resin.
The first test is a resin expansion test that involves heating the resin to determine its water content. The second test is a total organic carbon (TOC) analysis process that analyzes the amount of resin dissolved or decomposed by peroxide.

The data in Table 1 show that at peroxide levels of 500 ppm or higher, the resin dissolves within 24 hours in the prepared solution. At low peroxide concentrations, the humidity measurements measured by the resin swell test did not significantly change from sample to sample.
That is, the result is not proportional to the peroxide concentration. However, total organic carbon analysis is sensitive to very low peroxide concentrations and is a more accurate method of predicting resin life than the resin expansion test. TOC evaluation involves measuring TOC in the supernatant solution recovered after 7 days of testing. The data in Table 1 further show that the resin is severely affected by peroxide concentrations on the order of 5 ppm. During the test period, the peroxide concentration was measured by two different methods. Peroxide concentrations greater than 50 ppm were determined by the use of permanganate titration,
The low concentration was evaluated using EM Quant Paper® (manufactured by Merek Chemical Co.), which is sensitive to very low ppm concentrations of hydrogen peroxide.

Table 1 Experimental Results of Resin Life in Zinc Nickel Conductor Roll Cleaning Test Number Peroxide Concentration Temperature Resin Breaking Time Expansion Test Final Solution TOC (ppm) (° C) (days) Humidity (%) Analysis (ppm) 1 1000 60 1 dissolution 2 500 60 1 83.2 3 500 60 1 1 dissolution 4 250 60 60 1 81.8 5 100 60 60 2 66.1 6 50 60 2 63.2 7 50 50 60 2 62.6 8 25 60 2 51.7 9 0 60 40.1 10 25 60 4 76.0 11 15 60 4 65.9 12 15 60 4 66.6 13 10 60 7 69.2 183 14 7.5 7.5 7 62.7 126 15 15 7.5 60 7 57.2 131 16 5 60 11 63.8 104 17 0 60 52.9 2.2

Here again, as shown in FIG. 1, inlet means 18 is provided at the inlet of the bottom 3 of the housing 2 at the first end 4 of the filter F. The inlet means 18 has a main inlet conduit 20. Main inlet conduit 20 is filter F
Into the housing 2 and terminates at the inlet distribution manifold 22 located in the first gravel bed layer 10. The outlet means 24 extends from the second end 6 of the housing 2,
It has a main outlet conduit 26 and an outlet distribution manifold 28. The outlet distribution manifold 28 is located in the second end 6 of the housing 2 at a distance above the activated carbon bed 16.

An inlet distribution manifold 22 cooperating with the inlet means 18 is arranged horizontally and has an upper through hole 3
2 and a rectangular grid of PVC (polyvinyl chloride) tubing 30 with a lower through hole 34. The fluid entering the inlet means 18 passes through the through holes 32 and 34 and comes into contact with the gravel bed 8.
The tubes 30 are connected to form a series of equal sized individual rectangles or geometric shapes. The effect of this arrangement is to ensure a uniform distribution of fluid over the cross-sectional area of the filter device. The arrangement of inlet distribution manifold 22 further prevents high velocity flow from entering the filter and disrupting the filtration of fluid passing through the bed layer.
The inlet distribution manifold 22 is connected to the main inlet conduit 20 at a crossbar section 36 branching from the rectangular tube section 30. In addition, within the scope of the present invention, various geometrical lattice structures are included so that the dispersion of the fluid entering the filter is evenly distributed over the entire cross section of the gravel bed 8.

As shown in FIG. 1, an outlet distribution manifold 28 cooperating with the outlet means 24 is located above the activated carbon bed 16 at a distance. As shown in FIG. 2, the outlet distribution manifold 28 has a grid of PVC tubes 38 connected in series to form a horizontally located rectangle. As with the inlet distribution manifold 22, the arrangement of outlet tubes 38 is not limited to any particular geometry,
It also includes various geometric lattice structures that can evenly spread the fluid over a large cross-sectional surface area of the filter F. The crossbar portion 40 of the outlet distribution manifold 28 branches toward the rectangular tube portion 38, thereby connecting the main outlet conduit 26 to the outlet distribution manifold 28. The outlet distribution manifold 28 further includes a seamless woven polypropylene cloth filter 42 that completely covers the outlet tube 38. As best shown in FIG.
The polypropylin cloth filter 42 completely surrounds the outer peripheral surface of the outlet pipe 38. The outlet pipe 38 also has an upper vent or through hole 45 and a lower vent or through hole 47 through which fluid is collected and drawn into a reservoir 45 above the top of the activated carbon bed 16.

The action of the polypropylene cloth filter 42 is that the lumps of carbon and fine stones of the activated carbon bed 16 cause the outlet pipe 3
It is to prevent entering 8. These carbon lumps and particles are fluidized during the operation of the filter F and emerge from the activated carbon bed 16. The use of polypropylene cloth filter 42 over outlet distribution manifold 28 prevents the discharge of such a mass through outlet means 24 to an ion exchange resin bed or other device downstream of filter F. It Although polypropylene is a preferred cloth filter material, the invention is not so limited and various natural and synthetic fibers can be used.

As best shown in FIG. 1, a water level control sensing switch 44 is provided at the second end 6 of the housing 2 to control the oxygen vent 46 at the top 5 of the housing 2. There is. Treated fluid is activated carbon bed 1
Once filtered through 6, they collect to create a reservoir 45 in the second end 6 of the housing 2. The water level control sensing switch 44 has a float lever 48 that moves up and down in response to rising and falling of the fluid collected in the storage tank 45. The water level control sensing switch 44 opens the oxygen exhaust hole 46 and opens the housing 2 when the water level of the fluid in the storage tank 45 falls below the set point.
The oxygen collected in the area 79 is discharged.

The oxygen exhaust hole 46 has a suitable fluid line (not shown) for guiding the discharged oxygen gas to a region away from grease, oil or the like which can be safely treated. A further safety feature is the provision of a 2-inch pressure relief flange with a 15 psig burst disc 50. If the water level control sense switch 44 fails, the excess pressure created in the filter area 79 is released. The rupture disc 50 also has a fluid line (not shown) that allows gas to be removed from the filter F.

The inlet means 18 has a pressure switch 52 for measuring the differential pressure across the activated carbon bed 16. When a given change in differential pressure is measured, the filter F will automatically flow back to clean the activated carbon bed 16 of fine stones, suspended solids, organics and other traps.
Backflow is achieved by opening valve 54 which allows deionized water of backflow fluid source 56 to enter main inlet conduit 20 of inlet means 18. There is also a valve and conduit means 58 for guiding the backflow fluid through the gravel bed 8 and the activated carbon bed 16 to a collection reservoir 60 for subsequent processing.
Is provided at the second end 6. The inlet means 18 also has a valve 62 connected to an inlet fluid source 64 containing the fluid to be treated. A filter discharge pipe 68 that cooperates with the valve 66 is also provided.

A second pressure switch 70, similar in construction to the inlet pressure switch 52, is provided to cooperate with the outlet means 24. The second pressure switch 70 measures the differential pressure change across the outlet distribution manifold 28. As mentioned above, during the filtering operation, the carbon granules, agglomerates or entrapments from the activated carbon bed 16 are carried upward in the stream by the oxygen which is fluidized and released. These are collected in the treated fluid reservoir 45 and finally accumulated on the polypropylene cloth filter 42 of the outlet distribution manifold 28. The second pressure switch 70 detects the differential pressure change caused by the overly clogged cloth filter 42.

Air cleaning means are provided for periodically injecting air into the main outlet conduit 26 when a predetermined pressure drop across the outlet distribution manifold 28 is detected. This air cleaning means is a valve 74 for supplying pressurized air to the main outlet conduit 26 and outlet distribution manifold 28.
And a pressurized air supply source 72. These periodic jets of air blow off the lumps and carbon fine particles collected from the outside of the polypropylene cloth filter 42, and the outlet means 2
Ensure collection of processed fluid through 4. The outlet means 24 also has a valve 76 which collects in the reservoir 78 the fluid processed for final treatment by an ion exchange resin bed (not shown).

The relative positioning of the inlet means 18 at the bottom 3 with respect to the outlet means 24 at the top 5 results in a process cycle that is ascending. In this upflow, gas and liquid flow simultaneously through the filter. Applicant's studies have found that better hydrogen peroxide removal is achieved when the fluid to be treated is treated through activated carbon by ascending rather than descending. Although the present invention also works in downflow, downflow beds exhibit poorer results, especially at high flow rates.

In the downflow operation, gas is first formed at the top of the bed, and instead of escaping from the top, it accumulates in the bed where it is mixed with fluid and discharged through the bottom of the bed. It Applicants believe that the performance of the downcomer is poor.
It is believed to be due to the greater tendency of the countercurrent to trap gas in the floor waterways or "rat holes", lowering efficiency. On the contrary, the upflow design allows the oxygen gas generated during the catalytic destruction of hydrogen peroxide to be upflowed with the fluid and exhausted from the top of the filter.

In the preferred embodiment, the disclosed filter F operates in parallel with the second activated carbon filter except during backflow as described further below. The riser bed according to the preferred embodiment operates at 1-2 gpm / square foot. Applicants have selected a filter having a diameter of 54 inches and a depth of activated carbon bed 16 of about 30 inches. The nominal flow rate for a filter of that size is about 30 gpm. This is associated with a nominal flow rate of about 2 gpm / square foot with a dwell time of about 4 minutes. Generation of oxygen gas is about 0.6C
It is estimated by FM.

In operation, a waste liquid reservoir 64 containing hydrogen peroxide enters the inlet means 18 via the valve 62. This fluid containing peroxide rises up the main inlet conduit 20 at a rate of about 40 gpm and enters the bottom 3 of the filter F. There, the flow is split and directed by the crossbar tube section 36 into the inlet pipe 30 of the inlet distribution manifold 22. Fluid flows through the upper and lower through holes 32 and 34 to the inlet distribution manifold 28.
To enter the first gravel bed layer 8. Then, by flowing into the filter F, the fluid flows into the gravel bed layers 10, 1
Soak through 2 and 14.

As the fluid reaches the activated carbon bed 16, it continues to be filtered through the activated carbon bed 16 with the oxygen gas released along the way. Since the generated gas is mainly oxygen, it is considered that the main mechanism of peroxide destruction according to the present invention is not a reaction with activated carbon fine particles but an autocatalytic phenomenon.

As the fluid continues to rise through filter F, the oxygen gas with the peroxide-free fluid will be activated carbon bed 16
Begins to gather in the storage tank 45 above. Oxygen passes through the liquid,
Gather in area 79. The fluid that has been processed and collected in the reservoir 45 then passes through the polypropylene cloth filter 42 and the upper through hole 45 of the outlet tube 38 of the outlet distribution manifold 28.
And into the lower through hole 47.

Carbon agglomerates, granules and contaminants fluidized during operation of filter F are prevented from entering outlet manifold 28 by polypropylene cloth filter 42. In this way, the treated contaminant-free solution passes through the polypropylene cloth filter 42, into the outlet distribution manifold 28, and into the collection reservoir 78 through the main outlet conduit 26. This hydrogen peroxide free fluid is then directed to an ion exchange resin bed (not shown) without damaging the resin beads. Of course, within the scope of the invention,
It also includes the use of filters and treatments to remove hydrogen peroxide from solutions obtained from treatments other than electroplating wastewater regeneration systems.

When the hydrogen peroxide is catalytically destroyed during the treatment, the generated oxygen gas is filtered through the activated carbon bed 16 together with the purified liquid. This liquid is activated carbon bed 1
It is collected in the storage tank 45 above 6. Since the amount of released oxygen gas collected in region 79 is constantly increasing, the liquid level above activated carbon bed 16 is lowered. Then, when the bottom position is reached, the water level control sensing switch 44 is actuated by the movement of the float lever 48 of the water level control sensing switch 44, the oxygen exhaust hole 46 is opened, and the gas collected in the area 79 is removed from the filter F. Get out. On the other hand, the water level of the liquid starts to rise again due to the exhaust. The float lever 48 allows the level control sensing switch 44 to be actuated again and the oxygen vent hole 46 closed once the collected fluid reaches the top position.

During normal operation, the activated carbon fines fluidized in the activated carbon bed 16 accumulate outside the polypropylene cloth filter 42 surrounding the outlet distribution manifold 28, resulting in a reduced outflow of filter F. To do. To alleviate clogging of the polypropylene cloth filter 42, the second pressure switch 70 is activated when a predetermined pressure change due to clogging is sensed. At this time, the outlet valve 76 is closed while the valve 74 of the compressed air supply source 72 is opened. Pressurized air is injected into the outlet distribution manifold 28, which removes debris and particles that have accumulated outside the polypropylene cloth filter 42. This low pressure air flow reverses the direction of flow and removes particulates from the polypropylene cloth filter 42.

The pressurized air entering the outlet distribution manifold 28 is a relatively delicate polypropylene cloth filter 4.
It is maintained to minimize damage to 2. Compressed air is typically about 40 SCFM at 15 psig for about 15 seconds
It is injected at the above rate. When this cleaning is completed and the polypropylene cloth filter 42 is cleaned, the air control valve 74 is closed and the filter returns to the normal state. The outlet valve 76 and the inlet valve 62 reopen,
The fluid reenters the filter F for processing.

The filter continues to operate until excess solids are collected in the activated carbon bed 16 thereby creating a pressure drop across the filter. When a predetermined pressure drop is detected, the inlet valve is opened while the backflow valve 54 is opened to allow deionized water from the source 56 to enter the filter F via the inlet means 18. 62
And the outlet valve 76 is closed. The backflow pump (not shown) was started, and 160 gp in the filter F for about 10 minutes.
Send backflow fluid of m or more. This high rate water carries the liberated, floating solids out of the backflow conduit and valve 58 and into storage tank 60 for further processing. As can be seen, the filter F is backflowed in the upflow mode when the activated carbon bed 16 expands between 125% and 150% in size.

After backflow, the filter F is rested for about 3 minutes so that the activated carbon bed 16 slowly settles by gravity and is regenerated for further processing. During this time, the backflow outlet and valve 58 are closed while the drain valve 66 is open to allow fluid left in the filter F to exit the main inlet conduit 20 and enter the storage tank 68.

During the three minute exhaust period, valve 74 is opened and air flow from pressurized air source 72 enters filter F from top 5. The flow is about 15 SCRMs at 15 psi. This moderate air pressure helps drain backflow fluid through the outlet valve 66. The backflow fluid and the jetted air flow out of the filter F and enter the storage tank 68 for further processing. After draining, the backflow inlet valve 5 while the inlet valve 62 is open to supply the fluid 64 containing peroxide to the filter for the start of a new cycle.
4, the outlet valve 58, and the exhaust valve 66 are closed.

When the differential pressure switch 52 does not cause backflow, a timer assisting means (not shown) is provided to put the filter in the backflow mode at regular time intervals, and the activated carbon bed is irrespective of the state of the activated carbon bed. Reset the floor.

If multiple filters are used, they are combined so that they do not backflow at the same time. For example, in an electroplating waste metal recovery plant, the filter is sized to operate without interruption of the ion exchange bed while one of the two filters is being backwashed. By doing so, hydrogen peroxide can be removed continuously.

Although the present invention has been described with reference to the embodiments, the present invention is not limited thereto, and various further modifications, usage methods and / or applications are possible within the scope of the invention and the scope of the claims. is there.

[0045]

As described above in detail with reference to examples, according to the present invention, hydrogen peroxide can be effectively removed from a fluid by using activated carbon.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a filter device according to the invention, schematically showing inlet and outlet means.

2 is a sectional view along line 2-2 of the filter device shown in FIG. 1 showing an outlet distribution manifold having a cutout to expose the tube and a portion indicated by phantom lines.

FIG. 3 is a view showing a cloth filter and upper and lower through holes.
Sectional view of the distribution manifold taken along line 3-3 of FIG.

FIG. 4 is a diagram representing the percent destruction of hydrogen peroxide with time according to the present invention.

FIG. 5 is a diagram showing the efficiency of ascending filtration with respect to descending filtration according to the present invention.

[Explanation of symbols]

 2 Housing 4 First End 6 Second End 8 Gravel Bed 16 Activated Carbon Bed 18 Inlet Means 22 Inlet Distribution Manifold 24 Outlet Means 28 Outlet Distribution Manifold F Filter Device

Claims (48)

[Claims] 1. An activated carbon filter device for removing hydrogen peroxide from a fluid: a) a first end and a second end located about a vertical axis; and b) located at the first end of the device. C) a gravel bed; c) an activated carbon bed located at the second end of the device above the gravel bed; d) distributing the fluid to be treated to first contact the gravel bed and subsequently to the activated carbon bed. Activated carbon filter device for removing hydrogen peroxide from a fluid, characterized in that it comprises inlet means for contacting; e) outlet means for receiving the treated fluid exiting the device. 2. The filter device according to claim 1, wherein: a) the inlet means is located in the gravel bed and has a distribution manifold for broadly distributing the treated fluid to a cross-sectional surface area of the bed. An activated carbon filter device that removes hydrogen peroxide from a fluid. 3. A filter device according to claim 2 wherein: a) the distribution manifold comprises a rectangular grid of perforated horizontal tubes located in the gravel bed transverse to the vertical axis of the device. An activated carbon filter device for removing hydrogen peroxide from a fluid having. 4. A filter device according to claim 3, wherein: a) an activated carbon filter for removing hydrogen peroxide from a fluid, characterized in that the rectangular grid comprises a connected series of individual rectangles of the tubes. apparatus. 5. A filter device according to claim 3, wherein: a) an activated carbon filter device for removing hydrogen peroxide from a fluid, characterized in that the tube has upper and lower through holes. 6. A filter device according to claim 3, wherein: a) an activated carbon filter device for removing hydrogen peroxide from a fluid, characterized in that the tube is polyvinyl chloride. 7. A filter device according to claim 1 wherein: a) the outlet means comprises a distribution manifold located above the activated carbon bed in the second end and from a fluid to hydrogen peroxide. Activated carbon filter device that removes. 8. A filter device according to claim 7, wherein: a) the distribution manifold comprises a rectangular grid of perforated horizontal tubes located on the activated carbon bed transverse to the vertical axis of the device. An activated carbon filter device that removes hydrogen peroxide from a fluid. 9. A filter device according to claim 8, wherein: a) an activated carbon filter for removing hydrogen peroxide from a fluid, characterized in that the rectangular grid comprises a connected series of individual rectangles of the tubes. apparatus. 10. A filter device according to claim 8, wherein: a) an activated carbon filter device for removing hydrogen peroxide from a fluid, characterized in that the tube has upper and lower through holes. 11. A filter device according to claim 8, wherein: a) an activated carbon filter device for removing hydrogen peroxide from a fluid, characterized in that the tube is polyvinyl chloride. 12. A filter device according to claim 8 wherein: a) the tubing has a woven filter means for restricting foreign matter from entering the through holes of the distribution manifold. Activated carbon filter device that removes hydrogen oxide. 13. A filter device according to claim 12, wherein: a) an activated carbon filter device for removing hydrogen peroxide from a fluid, characterized in that the filter means comprises polypropylene material. 14. The filter device according to claim 2, wherein a) the first end is located at the bottom of the filter device; and b) the second end is located at the top of the filter device. Activated carbon filter device that removes hydrogen peroxide from the fluid. 15. A filter device according to claim 14, wherein: a) the second end has hydrogen and hydrogen peroxide removed from the fluid, wherein the second end has a fluid and gas collection region extending above the activated carbon bed. Activated carbon filter device. 16. The filter device according to claim 15, wherein: a) a fluid is provided in the second end for exhausting the gas accumulated in the fluid and the gas collecting region. Activated carbon filter device that removes hydrogen peroxide from water. 17. The filter device according to claim 16, wherein: a) the exhaust means opens and closes in response to the fluid and the fluid stored in the gas collection area to remove hydrogen peroxide from the fluid. Activated carbon filter device. 18. A filter device according to claim 17, wherein: a) the exhaust means comprises water level control means for monitoring both the fluid and the fluid stored in the gas collection area. Activated carbon filter device that removes hydrogen peroxide from the fluid. 19. A filter device according to claim 18, wherein: a) an activated carbon filter device for removing hydrogen peroxide from a fluid, characterized in that the water level control means is located above the distribution manifold. 20. A filter device according to claim 1, wherein: a) an activated carbon filter for removing hydrogen peroxide from a fluid, characterized in that the filter means comprises a hood which collects gas released during operation. apparatus. 21. A filter device according to claim 14, wherein: a) the inlet means and the outlet means are located within the device to direct fluid from the bottom of the filter device through the top. An activated carbon filter device that removes hydrogen peroxide from a fluid. 22. A filter device according to claim 1, wherein: a) an activated carbon filter device for removing hydrogen peroxide from a fluid, characterized in that the gravel bed comprises acid-resistant high silica stones. 23. An activated carbon filter device for removing hydrogen peroxide from a fluid according to claim 14, wherein: a) said gravel bed is stepped from said bottom to said top. 24. A filter device according to claim 23: a) An activated carbon filter device for removing hydrogen peroxide from a fluid characterized in that the gravel bed has large grains at the bottom and fine grains at the top. 25. A filter device according to claim 1, wherein: a) the fluid is characterized in that the gravel bed has a plurality of layers, each of the layers having gravel of different size. Activated carbon filter device that removes. 26. An activated carbon filter device for removing hydrogen peroxide from a fluid according to claim 25, wherein: a) the layer of gravel comprises fine, medium, coarse gravel. 27. The activated carbon filter device for removing hydrogen peroxide from a fluid according to claim 1, wherein: a) the activated carbon has a size of 12 × 40 mesh. 28. The filter device according to claim 15, wherein: a) the filter has a rupture disc in fluid communication with the fluid and gas collection region to relieve excess pressure in the filter. Activated carbon filter device that removes hydrogen peroxide from the fluid. 29. The filter device according to claim 1, wherein: a) a hydrogen peroxide from a fluid characterized by having a backflow means for flowing a washing fluid through the filter to clean the gravel bed and the activated carbon bed. Activated carbon filter device that removes. 30. A filter device according to claim 29: a) The backflow means has a differential pressure sensing means for detecting a pressure change before and after the activated carbon bed. Activated carbon filter device that removes. 31. A filter device according to claim 12, wherein: a) From a fluid characterized in that it has air cleaning means for injecting air into the outlet means for cleaning the accumulated debris of the filter. Activated carbon filter device that removes hydrogen peroxide. 32. A filter device according to claim 31, wherein: a) the air cleaning device has a differential pressure sensing means for sensing a pressure change across the outlet distribution manifold. Activated carbon filter device that removes hydrogen oxide. 33. A method of removing hydrogen peroxide from a fluid, comprising: a) providing a fluid containing hydrogen peroxide; and b) adding activated carbon to the fluid to catalytically destroy the hydrogen peroxide. A method of removing hydrogen peroxide from a fluid, comprising: contacting; and c) collecting a fluid substantially free of hydrogen peroxide. 34. A method of removal according to claim 33: a) Hydrogen peroxide from a fluid comprising the step of providing a bed of granulated activated carbon for contacting the collected fluid. Removal method. 35. A method for removing hydrogen peroxide from a fluid according to claim 34, comprising: a) contacting the fluid with a bed of activated carbon by a method of ascending. 36. A method for removal of hydrogen peroxide according to claim 34: a) removal of hydrogen peroxide from a fluid comprising the step of collecting accumulated gas released during contact of the fluid with the activated carbon bed. Method. 37. A method of removing hydrogen peroxide from a fluid according to claim 36, comprising: a) venting the collected gas. 38. A removal method according to claim 36, comprising: a) sensing the water level of the collected fluid; and b) venting the collected gas when a predetermined water level is reached. A method of removing hydrogen peroxide from a fluid. 39. A method of removing hydrogen peroxide from a fluid according to claim 33, comprising the steps of: a) backflowing the bed of activated carbon to clean and reorganize the granules. 40. A method according to claim 39, comprising the steps of: a) sensing the pressure before and after the activated carbon bed; and b) backflowing the activated carbon bed when a predetermined pressure change is sensed. A method for removing hydrogen peroxide from a fluid, comprising: 41. A removal method according to claim 1, comprising: a) providing a filter; and b) filtering the substantially hydrogen peroxide-free fluid while collecting the fluid. A method of removing hydrogen peroxide from a fluid. 42. A method of removal according to claim 41: a) removal of hydrogen peroxide from a fluid comprising the step of cleaning the filter by periodically ejecting air towards the filter. Method. 43. A method according to claim 42, comprising: a) sensing the pressure across the filter; and b) cleaning the filter when a predetermined pressure change is sensed. And a method for removing hydrogen peroxide from a fluid. 44. A method of removal according to claim 33: a) the destruction of hydrogen peroxide is about 82 within the first 2.5 minutes.
%, After about 10 minutes, at a rate of about 99%, a method for removing hydrogen peroxide from a fluid. 45. A method for removing hydrogen peroxide from a fluid according to claim 33, comprising: a) removing ferric iron from the fluid before contacting with activated carbon. 46. A method of removal according to claim 45, comprising: a) raising the pH of the fluid to a sufficient amount to precipitate ferric iron; and b) filtering the precipitate. And a method for removing hydrogen peroxide from a fluid. 47. A method for removing hydrogen peroxide from a fluid according to claim 46, comprising the step of: a) increasing the pH of the fluid with zinc oxide. 48. A method for removing hydrogen peroxide from a fluid according to claim 46, comprising the steps of: a) heating the fluid to about 130 ° F. before raising the pH.