CA1331686C - Oxidation chamber - Google Patents

Abstract

OXIDATION CHAMBER

ABSTRACT OF THE DISCLOSURE

An oxidation chamber for use in the treatment of organically contaminated water and waste liquids includes a lamp seal assembly that accommodates the thermal expansion of an ultraviolet lamp while at the same time protecting the lamp from direct contact with the liquid being treated.
The lamp seal assembly facilitates replacement of burned out lamps and cleaning of the protective tube that surrounds the lamp. In another aspect of the invention, a specially designed family of baffles and distributors are provided so that the chamber can accommodate a wide range of flow rates simply by replacing one set of distributors by a different set of distributors.

Description

Docket No. D-6623 ' ~3~t ~8~
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3 of 7 for 8 ~-g OXIDATION CHAMBER
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14 Field of the Invention The present invention is in the field of water or 16 wastewater treatment and specifically relates to apparatus 17 for use in destroying dissolv-d organic contamlnants in 18 the water or wastewater.
19 Hydrogen peroxide is added to the water or waste-water,~ which is then s~ubjected to intense ultraviolet 21 radiation. The ultraviolet radiation breaks the hydrogen 22 peroxide into hydroxyl radicals which are powerful oxidants.
23 These radicals attac~ and oxidize the organic contaminants 24 whioh~are also being~broken down by the ultraviolet radia- -25~ ~tion.~ Appl~ications~of~ the;apparatus include the detoxi-26~ fication of i~ndustria1 wastewater or the complete destruc-27~ tlon~o organLc contaminants in the water, the destruction 28~ of soLvents, pesticides and fuels, or other organic `
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"'' 1 contaminants found in groundwater, the destruction of 2 concentrated organically contaminated aqueous wastes, and 3 the production of high quality organic-free water for 4 industrial processes.
6 The Prior Art 7 The present invention is a part of a system for 8 treating liquids, usually water, containing undesirable g organic compounds to render those compounds harmless through the action of strong ultraviolet radiation and 11 through chemical oxidation.
12 The overall system includes an electrical power 13 supply, controls, an oxidation chamber, piping and wiring, 14 and a steel skid on which the other components are mounted.
The present invention relates to the oxidation chamber.
lB The li~uid to be trea~ed is caused to flow through the 17 oxidation chamber.
18 Full-scale systems have been installed at several 19 locations throughout the country and are operating routinely. -That this system operates with high reliability and safety 21 is attributable in large part to the engineering innovations 22 to be disclosed below, and is particularly surprising in view 23 of the potentiaI ~azards involved.
24 One model of the system is 15 feet long, 7 feet wide, and 8 feet high; it weighs 12,000 pounds. This unit 26 can process 500 gallons per minute of liquid, and uses 27 425 KVA of 3-phase a80 volt electrical power. A large part 28 Of this electrical power flows through quartz ultraviolet ///
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~331~86 1 lamps that are mounted within the oxidation chamber and 2 that are surrounded by the liquids that are being 3 treated. Clearly the system includes a number of poten-4 tially antagonistic elements--high voltages and currents in close proximity to li~uids and powerful reagents--.
6 In a very real sense, the inventions disclosed below have 7 made it possible for these antagonistic elements to 8 cooperate in achieving safe and reliable operation on a 9 scale never before attempted.
One can appreciate that the dissipation of 11 hundreds of kilowatts in a cold pressurized liquid 12 poses major challenges in materials sele:tion, in accom-13 modating thermal expansion, and in maintaining good sealing 14 of the chamber.
The unprecedented size and power of the apparatus 16 gave rise to a number of problems for which the prior art 17 provided no solutions, as will be described below.
18 For exam~ple, in U.S. Patent ~o. 3,485,576 issued 19 December 23, 1969 to McRae, et al., there is described an ultraviolet disinfection system in which a quartz lamp is 21 in direct contact with the liquid to be disinfected, and a `-~
22 simple O-ring seal is provided at each end of the lamp. In 23 contrast, the amount of power dissipated in the lamps of 24 the present inventîon ma~es it essential that the lamps be kept from direct contact with the liquid.
26 In U.S. Patent No. 4,273,660 issued June 16, 1981 27 to Beitzel, there is described a wat~r purification s~stem 28 ~i/

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, i 1~3i686 1 in which the cylindrical treatment chamber has an annular 2 cross-section. A tubular ultraviolet lamp extends axially 3 through the center hole. The cham~er appears to be of 4 unitary construction, and therefore localized thermal expansion will be a problem if a large amount of heat i9 6 dissipated by the ultraviolet lamp. Also, fouling of the q chamber wall adjacent the ultraviolet lamp will necessitate 8 replacing the entire chamber.
9 In U.S. Patent No. 4,694,179 issued September 15, 1987 to Lew, et al., there is described a device for puri-11 fying fluid media. The treatment chamber is cylindrical 12 in shape and the ultraviolet lamp is protected from the 13 fluid being treated by a tube that surrounds the ultra-14 violet lamp. End members at opposite ends of the tubular housing are said to include seals, but the sealing arrange-16 ment is neither shown nor specifically described. If the 17 drawings are indicative, the device does not appear to be 18 able to withstand an appreciable amount of thermal expansion g of the tube surrounding the lamp, rendering this approach unsuitable for use at high power levels such as those used 21 in the apparatus of the present invention.
22 Thus, the known prior art does not appear to provide 23 satisfactory approaches for use in the present large-scale 24 high power apparatus wherein multiple lamps are operated in Z5 a rectangular chamber.

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3 Prior to the present invention, conventional 4 thinking was that low pressure ultraviolet lamps should be used for an oxidation chamber because they are more effi-6 cient in the sense of producing more ultraviolet radiation 7 for each kilowatt of input power. Typically, the low 8 pressure ultraviolet lamps have smaller dimensions than the 9 medium pressure lamps used in the present invention and i~ 10 considerably lower power ratings per lamp than the medium 11 pressure ultraviolet lamps. The conventional approach 12 would therefore be to use a larger number of low pressure 13 lamps arranged around a transparent tube through which the 14 wastewater flows.
In a conventional design of that type, a reflector 16 is usually positioned behind the lamps in an effort to re-17 direct the part of the radiation that would not normally 18 enter the chamber. Reflectors for ultraviolet light are 19 not efficient, and in any case, some of the reflected light 20 will fall upon other lamps before reaching the water in the :~
21 transparent tube. Also, when large numbers of closely 22 spaced lamps are used,ian appreciable part of the radiation `-23 produced falls on adjacent lamps where it is lost by absorp-24 tion. All of these factors combine to impair the effi-.25 ciency of the conventional design.
26 Departing from this conventional design approach, 27 the present inventor chose to use a smaller number of 28 medium pressure lamps, each of considerably higher power 29 than the low pressure lamps. Because in the present inven-tion the lamps are completely surrounded by the water to be 31 treated, no radiation leaving the lamp is wasted and no 32 reflectors are needed.

~33~686 1 A number of advantages, not expected at the time 2 of the original design, have since been noted. The high 3 ultraviolet radiation intensity obtained from the medium 4 pressure lamps produces hydroxyl radicals from the hydrogen peroxide at a greater rate, and this causes the oxidation 6 reaction to proceed at a high rate, reducing the size of 7 the oxidation chamber required.
8 The presence of the medium pressure ultraviolet 9 lamps within the wastewater in the oxidation chamber results in considerable heatins of the wastewater, and this also 11 speeds up the reaction. Thus, the heat output of the medium 12 pressure lamps is not wasted.
13 Other advantages result from the use of the larger 14 medium pressure ultraviolet lamps. The number of medium pressure lamps required is only a fraction of the number 16 of low pressure lamps that would be required to obtain 17 equal radiation intensity. With fewer lamps, cleaning of 18 the ~uartz tubes surrounding the lamps can be performed 19 more often, and the cleaner tubes deliver more ultraviolet radiation.
21 The efficiency of low pressure lamps is high over 22 a relatively narrow operating temperature range. This tem-23 perature range is relatively close to the temperature of 24 the water being treated. Consequently, changes in the water temperature during treatment will appreciably change 26 the operating temperature of such a lamp. The end result 27 is that at the entrance to the oxidation chamber low pre-28 sure lam~s would operate below their optimum temperature 29 while at the exit of the oxidation chamber they would operate ab~ove their optimum temperature. This reduces the 31 overall efficiency of the low pressure lamp system.
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1 In contrast, medium pressure lamps are less 2 sensitive to changes in operating temperature and in any 3 case, they operate at such a high temperature that changes 4 in water temperature within the normal operating range have little effect on the lamp temperature. The end result ~S 6 is that the medium pressure lamps operate at near their 7 highest efficiency throughout the oxidation chamber.
8 Because the medium pressure ultraviolet lamps g are large enough to span the entire width of the oxidation chamber, end effects are proportionally smaller, resulting 11 in greater efficiency.
12 An additional advantage of using the larger 13 medium pressure ultraviolet lamps is that their drives 14 are more efficient in converting incoming power to lamp power than are the drives of smaller lamps.
~ 16 In summary, the use of medium pressure lamps has ;~ 17 resulted in the use of fewer lamps, leading to lower capital ,-18 costs, lower maintenance costs, and lower operating costs.
``~`~ 19 Although the use of medium pressure ultraviolet lamps in the oxidation chamber has proven to be a significant 1 21 advance in the art, it was not without some problems, which .-~ 22 the present invention has solved. Probably the most apparent ~-! ; ~
23 problem is the rather intense heating that occurs in the 24 ultraviolet lamp. To avoid placing too great a temperature gradient across the envelope of the lamp, it is necessary 26 to isolate the lamp envelope from the liquid being treated.
27 In accordance with the present invention, chis is accomplished 28 by enclosing the ultraviolet lamp within a quartz tube that 29 extends the entire width of the oxidation chamber and pro-` 30 jects at each end beyond the wall of the chamber.
31 Quartz was chosen as the preferred material for the 32 tube, because it provides the most favorable combination of ,~
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heat resistance, chemical resistance, ability to transmit 2 ultraviolet radiation, ability to withstand prolonged 3 exposure to ultraviolet radiation, and mechanical strength.
4 Another problem that was aggravated by the use .'! 5 of the longer medium pressure ultraviolet lamps is the 6 correspondingly larger amount of thermal expansion of the q lamp. Not only must the thermal expansion of the lamp be 8 accommodated, but also the thermal expansion of the quartz 9 tube that surrounds the lamp. In accordance with the present invention, a cylindrical aluminum plug is located ll at each end of the lamp and within the quartz tube. The 12 ends of the lamp extend into a central hole in the plug ~ ~ .
13 in a loose sliding fit. The plug also fits within the 14 quartz tube in a sliding fit. In this way, the plug supports the ends of the lamp, and by sliding, the plugs accommodate 16 the differential thermal expansion between the lamp and the 17 ~urrounding quartz tube. Each end of the quartz tube extends 18 through an 0-ring that encircles the quartz tube circum-l9 ferentially so as not to restrict its thermal expansion, while at the same time the O-ring serves as a seal.
21 This arrangement makes it possible to re ve the 22 quartz tube from the oxidation chamber for such purposes as 23 cleaning the quartz tubé when it has become foulèd. It 24 a}so allows for~replacing the quartz lamp without removal ~of th- quartz tube or draining the chamber.
26 Because of the relatively high currents and 27 volt_ges a~plied to the medium pressure ultraviolet lamps, 28 radio frequency interference radiated from the projecting ///

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1 portion of the lamp was found to reach undesirable levels.
2 This problem was solved by the addition of a tubular 3 member composed of phenolic that surrounds the projecting 4 end of the lamp and that is held in place by a phenolic cover plate. Comparatively little interference radiates 6 from the lead conductors, since they can employ a shielded 7 construction.
8 It is inevitable that variations in ultraviolet 9 intensity will exist between various points within the ~-oxidation chamber. Accordingly, it is highly desirable 11 that the flow of the liquid to be treated should be fully 12 mixed, rather than laminar. In accordance with the present 13 invention, this is accomplished by providing turbulence--14 introducing indentations on the oxidation chamber wall.
This arrangement serves to redirect any flow tending to 16 move along the wall past a lamp, eliminates an area farthest 1~ from the lamp that would tend to receive marginal ultraviolet 18 radiation, and also serves to strengthen the chamber wall.
19 To prevent objectionable material from collecting on the indendations, the sides of these indentations are sloped, 21 and the indentations extend without interruption along 22 the chamber wall.
23 It was recognized that the flow rate, in gallons 24 per minute, might change drastically from one installation to the next, and from time-to-time in response to changes 26 in the regulatory requirements. Also, it was recognized 27 that one installation may reauire flow to enter the 28 near side and exit the far side of the oxidation chamber, 29 while the next installation may be the opposite, or may 3 30 require that flow enter and leave the same side of the 31 oxidation chamber. In particular, rental units may require '`l ' " _ g _ ,~

133168~

one arrangement for a first installation and yet another 2 arrangement with a different flow requirement, at the 3 next installation. The present inventor addressed this need for flexibility in his design of the oxidation chamber.
In accordance with the present invention, each end ~ 6 of the oxidation chamber includes an upper port and a lower j 7 port. When not in use, these ports are sealed by steel 8 plates. Liquid is supplied to the oxidation chamber and 9 removed from it through specialized pipes, called distributors herein and sometimes referred to in the art as headers, that Il are inserted into the oxidation chamber through the ports.
12 Two types of distributors are used, as will : ~
13 become apparent hereinafter. The first type 14 has holes along its entire length for adding or removing liquid all across the oxidation chamber. The second type 16 has holes confined to a particular interval along its 17 }ength for adding or removing liquid to a localized region 18 of the oxidation chamber.
19 As will be seen below, when distributors of the first type are used, the liquid flows through the various 21 segments of the oxidation chamber in parallel, and when 22 distributors of the second type are used, the liquid flows 23 on~a serpentine path through the various segments of the 24 oxidation chamber in series. ~y providing these alternative types of distributors, the flow rate can be greatly altered 26 to suit the need of a particular installation while maintain- -27 ing;maximum turbulence and optim~m flow d~stribution The ~, 'J~ ~ 28 same oxidation chamber is used for all installations, and ; 29 only the relatively inexpensive distributors are changed to ` 30 alter the flow rate.
,~ 31 Additional design flexibility~is provided by the 32 lamp mounting arrangement which permits the number of lamps .

133168~
1 actually employed for a particular installation to be 2 selected in accordance with the needs of that installation. -~
3 Monitoring and control of oxidation chamber 4 performance is achieved by the use of sight ports and sensors that are inserted through the wall of the oxi-6 dation chamber. These sight ports permit a human operator 7 to safely view what is taking place within the oxidation 8 chamber. In addition, the site port can be altered to 9 accommodate an ultraviolet sensor for use in measuring the lamp output.
11 The novel features which are believed to be l 12 characteristic of the invention, both as to organization ¦ 13 and method of operation, together with further objects ¦ 14 and advantages thereof, will be better understood from the following description considered in connection with the 16 accompanying drawings in which a preferred embodiment of 17 the invention is i}lustrated by way of example. It is to 18 be expressly understood, however, that the drawings are for 19 the purpose of illustration and description only and are ~`20 not intended as a definition of the limits of the invention.

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J~ 24 BRIEF DESCRIPTION OF T~E DRAWINGS
1~ 25 i 26 Figure 1 is a perspective view of the oxidation ~7 chmber in a preferred embodiment of the invention, '3 ~ 28 ///

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1 partially cut away so that the parts inside the chamber 2 can be seen;
~ 3 Figure 2 is a fractional side elevational view j 4 partly in cross-section showing the lamp seal assembly;
Figure 3 is a diagram showing a flow arrangement 6 that can be produced in the oxidation chamber of Figure l;
7 Figure 4 is a diagram showing another flow 8 arrangement that can be produced in the oxidation chamber 9 of Figure l;
Figure 5 is a diagram showing another flow 11 arrangement that can be produced in the oxidation chamber 12 of Figure l;
13 Figure 6 is a diagram showing another flow arrange-14 ment that can be produced in the oxidation chamber of Figure l;
16 Figure 7 is a diagram showing yet another flow ~: 17 arrangementthat can be produced in the oxidation chamber 18 of Figure;
i~ 19 Figure 8 is an elevational view showing a : 20 baffle used in the oxidation chamber of Figure l; and, .~ 21 Figure 9 is a side elevational view in cross-22 section showing a sight port used in the oxidation 23 chamber of Figure 1.

26 DETAILED DESCR}PTION OF THE PREFERRED EM30DIMENT

28 Turning now to the drawings all of which relate 29 to the same preferred embodiment, and in which like parts : ~ 30 ///
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1 are denoted by the same reference numeral throu~hout, the 2 compactness of the structure of the oxidation chamber can 3 readily be appreciated from ~igure 1.
3 4 As seen in Figure 1, the oxidation chamber is a 5 box-like structure that includes a top wall 12, a bottom 6 wall 14, a front wall 16, a rear wall 18, a first end 4 7 wall 20, and a second end wall 22 (visible in Figure 6).
8 The liquid to be treated is supplied by the inlet 9 distributor 24, and the treated liquid is conducted from 10 the oxidation chamber through the outlet distributor 26.
11 The interior of the oxidation chamber is parti-12 tioned by a first baffle 28 and a second baffle 30. These 13 baffles, in association with various distributors, determine 14 the flow path of the liquid through the oxidation chamber, 15 as wiIl be discussed below in connection with Figures 3-7.
16 Also visible in Figure 1 are the tubes, of which 17 the tube 32 is typical~ which contain the ultraviolet lamps lB used for irradiating the liquid being treated. These tubes 19 pass through holes, of which the hole 34 is typical, in the 20 baffles.
` 21 Each of the lamp-enclosing tubes terminates at each 22 end in a lamp seal assembly, of which the assembly 36 is `1 23 typical. The assèmbly 36 is shown in greater detail in :
24 Figure 2.
As described above, it is vitally important that 26 the oxidation chamber be liquid-tight and that the ultra-27 vlolet lamps be prevented from c m-ng into direct c^r.t~ct ///

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.,' 1 with the liquid being treated. ~urther, the lamp should be 2 electrically insulated from the wall of the oxidation chamber 3 and also thermal expansion of the ultraviolet lamp and of its 4 protective tube must be accommodated. These requirements are met by the lamp seal assembly 36 shown in Figure 2.
6 In accordance with the preferred embodiment, the 7 lamp 42 extends across the entire width of the oxidation 8 chamber, from the first wall 20 to the wall 22, and --g actually extends outwardly beyond the walls of the chamber a short distance. The end portion 44 of the lamp 42 fits 11 into the cylindrical plug 52, which serves as a spacer to 12 keep the lamp centered within but spaced radially from the 13 tube 32. The cy}indrical plug 52 is composed of aluminum 14 or other heat and ultraviolet resistant material, and it fits with a loose sliding fit within the tube 32. Likewise, 16 the end portion 44 of the lamp fits into the cylindrical 17 plug 52 in a loose sliding fit.
18 The tube 32 is composed of quartz in the preferred 19 embodiment and passes through the aperture 48 in the chamber ~' ; 20 wall 20. An annular gasket 54 surrounds the aperture 48, 21 and a sealing contact is established between the chamber 22 wall 20 and the 0-ring retainer 56 by means of the gasket 54.
23 This sealing contact is maintained by pressure exerted.by 24 the compression plate 60 against the 0-ring retainer 56 when .~ ~ ~
the nuts 62 are tightened on the studs 64. The 0-ring 58 26 esta.blishes a seal between the tube 32 and the 0-ring 2~. retainer 56.
2~ Conventional practice would have suggested sealing 30 /// .

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`-` 133~6~6 . . , 1 the tube 32 directly to the chamber wall 20 by a single 2 0-ring seal, in the manner suggested by the aforementioned 3 U.S. Patent ~o. 3,485,576. However, that approach would -~
4 have required machining of the chamber wall, with the result that any damage to the machined surfaces would 6 require replacement of the entire chamber.
7 In contrastj the present invantor has devised a ~ 8 seal that requires no machining of the chamber wall (except, x 9 of course, for providing the aperture 48) and which maintains 10 a tight seal even as the tube 32 expands and contracts. In 11 accordance with the present invention, ~his is achieved by 12 first establishing a seal between the chamber wall 20 and 13 the 0-ring retainer 56 by means of the gasket 54, and then 14 achieving a seal between the tube 32 and the 0-ring retainer 56 15 by means of the 0-ring 58. In this preferred embodiment, if 16 the gasket 54, the 0-ring 58, or the 0-ring retainer 56 be-17 comes defective, the defective part can be readily replaced.
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18 The portlon of the lamp that projects outslde of 19 the chamber wall 20 acts like a radio antenna when electric 20 current is applied to the lamp 42 on the wire~66, which is 21 insulated from the cover plate 68 by means of the feed-through 70.
22 To reduce the electromagnetic emanations, in the preferred 23 embodiment the pro~ectinq portion of the lamp 42 is surrounded 24 by the cover tube 72, which is composed of phenolic. A first 25 end 76 of the cover tube 72 bears against the compression 26 plate 60, and the second end 78 of the cover tube 72 bears 27 again~t .he co-~cr plate 68. The cover tube 72 is held in 28 position by pressure exerted by the cover plate 68 when i, .
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~3~16~6 1 the nuts 74 are tightened. The cover tube 72 includes a 2 downwardly directed hole 80 through which liquid can be 3 discharged in the unlikely event that the tube 32 breaks 4 or o-ring 58 leaks.
Figures 3-7 are a set of diagrams that show a 6 number of ways in which the oxidation chamber can be con-figured to alter the lccations of the input and output 8 distributors and, more importantly, to permit the oxidation g chamber to be adapted for use with an extremely wide range of volumetric flow rates. It will be noted that in 11 Figures 3-5, the inlet and the outlet are on opposite ends 12 of the chamber, while in Figures 6 and 7, the inlet and 13 outlet are on the same end of the chamber. Further, it 14 will be noted that in Figures 3, 4 and 6, the liquid follows a serpentine flow path that passes through the three segments 16 of the chamber in series. In contrast, in Figures 5 and 7, 17 the liquid flows in parallel through the three segments of 18 the chamber. Thus, Figures 3-7 cover the four possible 19 combinations cf connections and flow paths. It is also -noteworthy that no change to the oxidation chamber itself 21 is required witi any of these configurations, and the 22 positions of the baffles remain the same in Figures 3-7. ;
23 The difference i~ the flow paths is not produced by a!lter-24 ing the positions of the baffles, but instead is produced by the selection and installation of the inlet distributor 26 and the outlet-distributor.
27 Prom Figures 3-7 it can a'so be seen that there 28 are three types of distributors used: a short distributor 29 such as the distributor 90 of Figure 3 which spans one segment of the chamber; a long distributor of the type 31 exemplified by the distributor 92 of Figure 4 having holes , ~_7 -- ~33~ ~8~
1 only in the last segment of its length; and, a long dis-2 tributor such as the distributor 94 of Figure 5 that has 3 holes throughout its entire length.
4 All of the possible combinations shown in Figures 3-7 can be constructed if two distributors of each of the 6 three types are provided. These six distributors and the 7 oxidation chamber may be thought of as constituting a kit 8 of parts from which any of the configurations of Figures 9 3-7 can be constructed by selection of the appropriate distributors.
11 The distributors are relatively simple and in-12 expensive parts, and by appropriate selection of these 13 distirubtors, the basic oxidation chamber can be adapted 14 to any of the configurations shown in Figures 3-7. This 15 feature of the preferred embodiment greatly extends the ~-16 versatility of the basic oxidation chamber.
17 The basic oxidation chamber is provided with upper 18 ports 100, 102 on its first end wall 20 and second end 19 wall 22, respectively and is provided with lower ports 104, ~ 20 L06 on the first end wall 20 and second end wall 22, `~ 21 respectivély. Only one upper port and one Iower port are 22 used at any particular time, and the unused ports are `
23 sealed with covers, of which the covers 96~and 98 are! typical.
24 The distributors, of which the distributor 92 of Figure 4 is typical, include a length 108 of pipe closed at 26 the end 110 that is inserted into the chamber, and provided 27 at its opposite~end 112 with a flange 114. ~he length of `-~ 28 pipe 108 includes a number of holes, the location of which `~ 30 ///
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1 depends on the type of distributor. For example, in the 2 short distributor 90 of Figure 3, the holes are located to 3 supply liquid only to the first segment of the chamber;
4 in the longer distributor 92 of Figure 4, the holes are located near the end 110 for supplying liquid to or removing 6 liquid from only one segment of the chamber; the long dis-7 tributor 94 of Figure 5 is provided with holes along its 8 entire length so as to permit it to supply liquid to or 9 remove liquid from all of the segments of the chamber simultaneously.
11 All of the configurations in Figures 3-7 make use -12 of a single pair of baffles 28, 30. It is considered to be within the scope of the present invention to add additional 14 pairs of baffles, and in general to have N pairs of baffles, which would partition the oxidation chamber into 2N+l 16 segments. The segment nearest the wall 20 would be referred 17 to as the first segment, while the segment adjacent the 18 wall 22 would be referred to as the last segment. Likewise, 19 the baffles closest to the walls20 and 22 would be called, respectively the first and last baffles.
21 Further versatility with regard to flow rate can 22 be obtained through the use of larger or smaller holes in 23 the distributors. 1 ~
24 Figure 8 shows a typical baffle 120. It should be noted that the baffles 28 and 30 are identical in shape.
26 Each baffle includes a relatively larger hole 122 to permit 27 passage of a distributor, and also includes a number of smal;er 28 holes, of which the hole 124 is typical, to permit passage of 29 /~/
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1 the tubes 32 that contain the ultraviolet lamps 42. Because 2 the baffles all have the same shape, and because they are 3 mounted on the planar walls of the chamber, it is clear 4 that the holes are in registration. The notches in the edges of the baffle, of which the notch 126 is typical, 6 accommodate grooves in the front wall 16 and rear wall 18.
7 These grooves introduce turbulence to the flow of liquid 8 through the chamber. They also prevent the liquid from g occupying a space where the ultraviolet radiation is less 10 intenSe.

11 The length of the baffle 120 is less than the ~ 12 internal height of the oxidation chamber, so that when the ! 13 edge 128 is attached to the top or bottom wall of the chamber, 14 the opposite edge 130 is spaced from the opposite wall. This permits the construction of the serpentine flow paths shown 16 in Figures 3, 4 and 6.
17 Although the baffle 120 includes a number of holes 124 18 for installation of ultraviolet lamps, it is not necessary for 19 aIl of the lamp positions to be filled. This permits the number of lamps and their location to be altered as might 21 be required by changing flow rates, concentrations of con-22 taminants, contaminant characteristics, or regulatory require-23 ments. I
24 The apertures 48 in the first end wall 20 and second end wall 22, through which the tubes 32 extend are arranged 26 in a pattern that matches the pattern of the holes 124 on 27 the baffle 120. When not all or the possible ultraviolet :

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1 lamps are used, the unused apertures can be close~ by plugs 2 (not shown).
3 Monitoring and control of the performance of the 4 oxidation chamber is facilitated by sight ports of which the sight port 136 shown in Figure 1 and in greater detail 6 in Figure 9 is typical. In the preferred embodiment, the 7 sight port 136 includes a housing 138 that is welded to the 8 front wall 16 of the oxidation chamber. A quartz window 140 g fits snugly within a bore in the housing 138 and is sealed by the gaskets 142, 144, which are maintained in compression 11 by the threaded retainer 146. An acrylic window 148 is 12 located on the outside of the ~uartz window, and the window 13 148 is held in position by a readily removable 0-ring 150.

14 This arrangement allows safe viewing of lamp performance because the window 148 absorbs potentially harmful ultra-16 violet radiation, while the required heat, chemical 17 resistance,and strength,along with good ultraviolet trans-18 missivity~is provided by th quartz window 140. When the 19 ultraviolet radiation intensity is to be measured, an authorized serviceman removes the 0-ring 150 and the 21 acrylic window 148 to permit an ultraviolet radiation 22 sensor to be positioned directly in front of the quartz 23 lens so that the ultraviolet intensity can be measured to 24 determine the need for lamp replacement and/or tube cleaning, 25 ~without disassembly of any water-retaining part of the 26 oxidation chamber.~
27 Thus, there has been described an oxid~ion chamber ~ :

1~31686 1 having a structure that permits it to be readily adapted 2 to a wide range of flow rates and conditions by the 3 relatively simple operation of substituting one set of ~,4 distributors for another set.
~5 The oxidation chamber employs a novel lamp sealing i~6 assembly which facilitates cleaning of the tube which 7 protects the ultraviolet lamp and allows for convenient 8 replacement of the ultraviolet lamp when necessary.
9 The foregoing detailed description is illustrative ~10 of one embodiment of the invention, and it is to be under-n11 stood that additional embodiments thereof will be obvious 12 to those skilled in the art. The embodiments described 13 herein together with those additional embodiments are 14 considered to be within the scope of the invention.
What is claimed is:

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Claims (6)

1. Apparatus for mounting an elongated ultraviolet lamp having an end portion within a liquid-filled chamber in such a way that the end of the lamp extends out through an aperture in the chamber wall, said apparatus noteworthy for not requiring any machining of the chamber wall other than that required to produce said aperture, for electrically insulating the lamp from the chamber wall, for sealing the aperture in the chamber wall, for preventing the liquid from coming into direct contact with the lamp, and for permitting thermal expansion of said lamp, said apparatus comprising in combination:
a tube surrounding said lamp but spaced radially from it, one end of said tube extending through the aperture in the chamber wall to an end located outside the liquid-filled chamber;
a cylindrical plug having an outside diameter slightly less than the inside diameter of said tube to permit said cylindrical plug to slide freely within said tube, and having a central bore of suitable size and shape to accommodate the end portion of said lamp in a sliding fit, whereby said cylindrical plug serves to maintain the radial spacing between said lamp and said tube, while permitting said lamp to expand axially within said tube;

a gasket lying against the outside of the chamber wall and surrounding the aperture in the chamber wall;
an O-ring retainer encircling said tube and lying against the side of said gasket opposite the chamber wall, and including a groove for retaining an O-ring in sealing contact with said tube;
an O-ring lodged in the groove of said O-ring retainer and sealingly engaging said tube;
a compression plate oriented perpendicular to said tube and bearing against said O-ring retainer; and, means interconnecting the chamber wall and said compression plate for drawing said compression plate against said o-ring retainer, whereby said gasket is compressed causing said gasket to sealingly engage both said O-ring retainer and the chamber wall.

2. The apparatus of claim 1 further comprising in combination:
a cover tube coaxial with said tube and surrounding it but radially spaced from it, having a first end bearing against said compression plate and extending from said compression plate away from the 1iquid-filled chamber to a second end;
a cover plate oriented perpendicular to said tube and bearing against the second end of said cover tube; and, means interconnecting the chamber wall and said cover plate for drawing said cover plate against the second end of said cover tube whereby said cover tube serves as a spacer between said compression plate and said cover plate, enclosing the end of said lamp without interfering with thermal expansion of said lamp.

3. The apparatus of claim 2 wherein said cover tube is composed of phenolic.

4. The apparatus of claim 2 further comprising a hole extending through the wall of said cover tube; whereby if a leak in the tube develops, the liquid is vented through the hole.

5. Apparatus for mounting an elongated ultraviolet lamp having an end portion within a liquid-filled chamber in such a way that the end of the lamp extends out through an aperture in the chamber wall, said apparatus noteworthy for not requiring any machining of the chamber wall other than that required to produce said aperture, for reducing electromagnetic emanations produced when the lamp is in operation, for electrically insulating the lamp from the chamber wall, for sealing the aperture in the chamber wall, for preventing the liquid from coming into direct contact with the lamp, and for permitting thermal expansion of said lamp, said apparatus comprising in combination:
a tube surrounding said lamp but spaced radially from it, one end of said tube extending through the aperture in the chamber wall to an end located outside the liquid-filled chamber:
a cylindrical plug having an outside diameter slightly less than the inside diameter of said tube to permit said cylindrical plug to slide freely within said tube, and having a central bore of suitable size and shape to accommodate the end portion of said lamp in a sliding fit, whereby said cylindrical plug serves to maintain the radial spacing between said lamp and said tube, while permitting said lamp to expand axially within said tube;
a gasket lying against the outside of the chamber wall and surrounding the aperture in the chamber wall;
an O-ring retainer encircling said tube and lying against the side of said gasket opposite the chamber wall, and including a groove for retaining an o-ring in sealing contact with said tube;
an O-ring lodged in the groove of said O-ring retainer and sealingly engaging said tube;
a compression plate oriented perpendicular to said tube and bearing against said O-ring retainer;
means interconnecting the chamber wall and said compression plate for drawing said compression plate against said O-ring retainer, whereby said gasket is compressed causing said gasket to sealingly engage both said O-ring retainer and the chamber wall;
a cover tube composed of a phenolic compound, coaxial with said tube and surrounding it but radially spaced from it, having a first end bearing against said compression plate and extending from said compression plate way from the liquid-filled chamber to a second end;

a cover plate oriented perpendicular to said tube and bearing against the second end of said cover tube; and, means interconnecting the chamber wall and said cover plate for drawing said cover plate against the second end of said cover tube whereby said cover tube serves as a spacer between said compression plate and said cover plate, enclosing the end of said lamp without interfering with thermal expansion of said lamp.

6. The apparatus of claim 5 further comprising a hole extending through the wall of said cover tube, whereby if a leak in the tube develops, the liquid is vented through the hole.