DIY Ozone - Let’s Make Some Ozone!

[Flyer]

Let’s Make Some Ozone!

Ozone is a very interesting gas that is often present in the vicinity of electrical arcing. It has a very distinctive smell and that's why its name was derived from the Greek word ozein which means "to smell".
It is a strong airborne oxidant that can be used to refresh the air by destroying atmospheric germs and odors, care must be taken with the quantity produced though, since levels that can be smelled are capable of causing irritation to sensitive areas of the body like the eyes and nose.
Because of its strong odor destroying properties ozone is often used to refresh the air in public facilities and can be used to reduce the smell of smoke damage in a building, or bubbled through water to provide a more effective sterilization than chlorine without any residual taste or smell. It's most notorious use must be for the suppression of the smell from cannabis plants in illegal growing rooms.

It's very easy to make ozone, since it is done by applying Ultra Violet energy or electrical discharge energy to either pure oxygen, or more commonly just plain air. The energy of the UV or arc causes the two atoms of a molecule of oxygen to separate, and some recombine temporarily in an unstable three atom molecule of ozone. The third oxygen atom is quickly donated to anything in the vicinity and oxidizes it in the process. Ozone must be made on demand since it cannot easily be stored.

Here are three approaches to making ozone. The first is a simple low level ozone maker which is ideal as an air freshener while the second is a UV technique. The third is a planar plasma technique which can produce a lot of ozone.


http://www.cannabis-world.org/cw/picture.php?albumid=107&pictureid=941&thumb=1 (http://www.cannabis-world.org/cw/picture.php?albumid=107&pictureid=941)


Here's a simple unit for creating low levels of ozone on a continuous basis. It's a very reliable design and has a few rather unique features. The hand in front of the unit is to indicate its size and also indicate that quite a strong electronic draught comes from the front despite the unit having no moving parts!

http://www.cannabis-world.org/cw/picture.php?albumid=107&pictureid=942&thumb=1 (http://www.cannabis-world.org/cw/picture.php?albumid=107&pictureid=942)

Here's how it works... A voltage multiplier like the one on the ionizer page is used to apply a high negative voltage to a needle. Unlike an ionizer which projects ions straight into the air, this unit is encouraged to emit ions by having a short metal tube at the opposite potential placed in front of the needle. This causes a strong corona to appear at the needle tip, and the high volume of ion discharge over to the tube causes a strong airflow which carries ozone from the needle tip corona out into the room.
The schematic above shows a couple of resistors between the power supply and the tube. This is to avoid having the tube at mains potential when the circuit is used with a mains powered voltage multiplier.

http://www.cannabis-world.org/cw/picture.php?albumid=107&pictureid=943&thumb=1 (http://www.cannabis-world.org/cw/picture.php?albumid=107&pictureid=943)

This unit was thrown together experimentally, and uses a 30 stage 220n mains powered (240V) voltage multiplier which has been split into sections to save space. There's more information on these multipliers on the ionizer page.

The connections between the sections of voltage multiplier are just thin hookup wire, since the potential between stages is relatively low at a few hundred volts. The output goes via the usual safety resistor/s and also passes through a neon and capacitor based current flow indicator as used on the ionizer page. The final output is on three needles pointing at three short tubes made from brass eyelets soldered to self adhesive copper tape. The tubes are all connected to mains neutral via a few safety resistors.

http://www.cannabis-world.org/cw/picture.php?albumid=107&pictureid=944&thumb=1 (http://www.cannabis-world.org/cw/picture.php?albumid=107&pictureid=944)

Here's a close-up view showing the emitter and tube, and also the neon output level indicator.

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This is an experimental ozone generator based on a mercury discharge lamp. It has a fan and uses a resistor to limit the current through a quartz tube mercury discharge lamp which has been removed from a commercial mercury vapor lamp.

It must be stressed that without the glass envelope of the lamp to act as a filter, the quartz tube passes the more harmful ultraviolet wavelengths which CAN CAUSE EYE DAMAGE and sunburn. Even though the tube in this design was operated at a very low current, it was still shielded completely in a metal case to prevent anyone from staring at the lamp and suffering possible eye damage.

The design certainly produced ozone, but I think I'm under-running the lamp to the point that it has blackened inside quite severely, although running it at a higher current briefly might help clear the blackening. I might re-visit this project at some point.

http://www.cannabis-world.org/cw/picture.php?albumid=107&pictureid=946&thumb=1 (http://www.cannabis-world.org/cw/picture.php?albumid=107&pictureid=946)

To help the mercury tube strike, a resistor of about 220K should be wired between one end of the tube and the little auxiliary electrode at the other end. The tube MUST be in series with a resistor or choke to limit the current through it.

http://www.cannabis-world.org/cw/picture.php?albumid=107&pictureid=950&thumb=1 (http://www.cannabis-world.org/cw/picture.php?albumid=107&pictureid=950)

Here's the really violent way to make tons of ozone. It's basically a thin piece of glass with metal mesh stuck to both sides. When about 5kV is applied to the meshes, a large area corona discharge occurs between the mesh and glass on both sides. This makes a LOT of ozone.

http://www.cannabis-world.org/cw/picture.php?albumid=107&pictureid=951&thumb=1 (http://www.cannabis-world.org/cw/picture.php?albumid=107&pictureid=951)

The mesh is tacked to the glass at regular intervals by squirting hot melt glue directly through it and onto the glass. Silicon would probably stick better and withstand the oxidizing effect of the ozone, but hot melt is much easier.

The mesh must be cut smaller than the glass to avoid arcing at the edges, and it must be tacked frequently while leaving a small gap between the mesh and glass to allow airflow through the corona. If it is tacked too far apart it will buzz noisily when powered up.

http://www.cannabis-world.org/cw/picture.php?albumid=107&pictureid=952&thumb=1 (http://www.cannabis-world.org/cw/picture.php?albumid=107&pictureid=952)

The neon transformer wires are attached directly to the metal mesh which should be stainless steel to avoid oxidation problems. I used copper mesh since it was freely available in the prop-shop where it is used as a malleable form for clay structures.

I've really gone to town on tacking the wires down with hot melt glue, although in hindsight if I had attached the wires centrally along one edge, the whole panel could have been suspended from the ceiling by it's wires. I suppose silicon would be better for this bit, since it would definitely adhere to the glass better for hanging.

The unit makes a soft FRRRRRR! Noise while powered and a very faint corona discharge is visible in a very dark room. The current involved is very low with an A4 sized panel passing about 1mA at 5kV.
The reason for the glass is as a barrier between the mesh electrodes. If it wasn't there they would just arc across noisily, however with the glass in place the whole arrangement turns into an air and glass dielectric capacitor, and the controlled charge transfer across the air (corona) splits the oxygen into ozone.

http://www.cannabis-world.org/cw/picture.php?albumid=107&pictureid=947&thumb=1 (http://www.cannabis-world.org/cw/picture.php?albumid=107&pictureid=947)

Here's a commercial British ozone generator that is often found in public restrooms as an air sanitizer.
The fact that it uses no chemicals, and genuinely destroys airborne bacteria and odors means that it is a cost effective alternative to traditional air freshener sprays and gels. Just fit and forget.

http://www.cannabis-world.org/cw/picture.php?albumid=107&pictureid=948&thumb=1 (http://www.cannabis-world.org/cw/picture.php?albumid=107&pictureid=948)

The round electrodes are very smart and robust, and the tubular arrangement gives the mesh rigidity which reduces noise to a faint fizz.
The transformer at the right hand side is a continuously rated 5kV boiler ignition transformer with one end of the 5kV secondary grounded internally. Its HT output is connected to the corona tubes by terminals at their ends.

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The electrodes couldn't be simpler. A scroll of stainless steel mesh is pushed into a Pyrex test-tube where it unfurls against the walls and a lug on the end makes connection to the circuit through a nut and bolt through the screw-on lid.

A stainless steel mesh tube on the outside of the test-tube acts as the other mesh electrode and is connected to ground via the terry clip mountings that hold the assembly in place.

***Please do not jump into this project without fully reading, asking questions and understanding first. ***

[Monseigneur Stroganoff]

moahaha

[memyselfandi]

the lamps are safer, the high voltage ozone generator as some side effects.

i am going to find the info i have it somewhere

Can you post more info on the lamp version, that would be great

[memyselfandi]

ps: you rock

Hooo found what i wanted ( not really but the info is there, i am on holidays so forgive me)

The corona needs air humidity and produces nitric acids and you can't really control it

http://www.o3ozone.com/compare_features/ultraviolet_vs.htm

[Flyer]

the lamps are safer, the high voltage ozone generator as some side effects.

i am going to find the info i have it somewhere

Can you post more info on the lamp version, that would be great

Thanks for the replies.

I absolutely agree that the lamps are safer, it is what I use.

But the lamps are not always available. It is always best to get a comercially available bulb like those sold by http://www.blueairproducts.com/index.html. If the bulb is unavailable, you can use a mercury vapor lamp. If you remove the inside bulb, this will produce ozone as pictured above. If mercury vapor bulbs are not available, corona arc type is your next choice.

The ion generator pictured above in the first couple of pictures is also nice in that it creates negative ions which attach themselves to odor molecules. After attaching themselves, they become negatively charged and tend to fall to the ground or attach themselves to items close by. This works really well for odor control.

One great thing about ozone is that it oxidizes. It will remove odors and destroy living matter. Therefore it must be regulated in the grow room. Too much may harm you or your plants, but at the correct dialed amount, it can destroy small pests like gnats and spider mites and nutralize unwanted odor.
:kind:

[Flyer]

Need some cheap ozone?

Here's an experimental ozone generator based on readily available parts that you can build cheaply to clean up the air in your surroundings or get rid of strong odors. I think the latter will appeal to the people who grow exotic herbs in their homes, or live in damp climates where mould is a problem.

This project generally works well, but its output depends on the components used. It's also very much a bare-bones experimental device so you build it entirely at your own risk.

http://www.cannabis-world.org/cw/picture.php?albumid=108&pictureid=953&thumb=1 (http://www.cannabis-world.org/cw/picture.php?albumid=108&pictureid=953)

This project generates ozone using corona discharge. This involves generating a high voltage electrical discharge and then blowing air past it. As the air passes through the corona the oxygen molecules are temporarily separated into individual oxygen atoms and when clear of the corona they start to recombine back into oxygen (O2) and ozone (O3). Since ozone is unstable it will readily donate the extra atom of oxygen to anything that will take it, and this results in a strong oxidizing effect which can destroy odors and kill airborne viruses and mould.
Ozone has a very short lifetime, typically reverting back to oxygen again within an hour.

http://www.cannabis-world.org/cw/picture.php?albumid=108&pictureid=954&thumb=1

The most efficient way of creating ozone is with corona discharge. To create a controlled corona discharge you place an insulator between two high voltage electrodes. Without the insulator the current will arc between the electrodes and generate some ozone but also produce a lot of heat. With the insulator in place the current can't arc directly across and instead a charge is transferred back and forth in the style of a capacitor with the charge manifesting itself as a purple corona discharge. This requires the use of AC and you can get more coronas in a smaller area using high frequency AC.

http://www.cannabis-world.org/cw/picture.php?albumid=108&pictureid=955&thumb=1 (http://www.cannabis-world.org/cw/picture.php?albumid=108&pictureid=955)

A very common method of producing corona in a very compact form is the use of a corona plate. This is a piece of thin ceramic or glass with an electrode on each side that mirrors the other side without any significant overlap. When a high voltage is applied across the electrodes a corona line forms at the points where the top and bottom electrodes would touch if the insulator was not in the way. This arrangement is extremely efficient since the insulator can be very thin and this allows use of a much lower voltage, typically one to two kilovolts per millimeter.

The insulating material must be able to stand up to the high voltage, corona discharge and ozone, so it is generally glass or ceramic with ceramic the most common choice. The electrodes must also be able to withstand the arduous corona and ozone environment and would ideally be stainless steel with aluminum also being fairly suitable.

http://www.cannabis-world.org/cw/picture.php?albumid=108&pictureid=956&thumb=1 (http://www.cannabis-world.org/cw/picture.php?albumid=108&pictureid=956)

This is an example of a typical manufactured corona plate. The bottom electrode is mirrored on the back so that there is minimal overlap, and the high voltage is connected to the plate by the same spring clips that hold it in place.

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As you can see, the ceramic is very thin at less than a millimeter. One of the main benefits of ceramic plates is that they have a very high dielectric strength, which basically means they can handle a much higher voltage without arcing through.

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This was the result of an experiment I did with a bit of very thin PCB laminate with copper electrodes etched on either side. It worked for several hours with the corona visibly destroying the resin that bonds the glass fiber together, until it suddenly arced through. When a plate fails the current will all tend to arc through in one small point and cause a lot of heat in that area.

http://www.cannabis-world.org/cw/picture.php?albumid=108&pictureid=959&thumb=1 (http://www.cannabis-world.org/cw/picture.php?albumid=108&pictureid=959)

In my search for suitably thin insulating material to make cheap corona plates from I completely failed to find thin ceramic sheet at anything near an affordable price. Instead I found that glass microscope slides are pretty good with a thickness of about 1mm. I also tried large slide covers that were a very fragile .2mm thick, but they were very hard to apply the electrodes to without breaking them, and also failed electrically at about 2kV.

http://www.cannabis-world.org/cw/picture.php?albumid=108&pictureid=960&thumb=1 (http://www.cannabis-world.org/cw/picture.php?albumid=108&pictureid=960)

There are a few electrode arrangements you can make that determine the number of corona lines and thus the corona output, although that will also be determined by the output current capability of your high voltage supply.
I've shown two electrode arrangements, with yellow tape representing the bottom electrode and blue representing the top one. I'll mention again that there should not be excessive overlap, since any overlap will just pass AC current like a capacitor without producing any corona.
In the above designs the two part version produces two lines of corona (one top and one bottom) while the three part electrode arrangement produces four lines of corona. Try the simple two electrode version first though, since it's much easier to make.

http://www.cannabis-world.org/cw/picture.php?albumid=108&pictureid=961&thumb=1 (http://www.cannabis-world.org/cw/picture.php?albumid=108&pictureid=961)

I used self adhesive aluminum foil for my prototype. I started by applying a piece over half the glass plate as shown above.

http://www.cannabis-world.org/cw/picture.php?albumid=108&pictureid=962&thumb=1 (http://www.cannabis-world.org/cw/picture.php?albumid=108&pictureid=962)

I then used a sharp knife to cut and peel the ends away from either side so that there was no risk of arcing around the side of the glass if the electrodes were too close to the edge.

http://www.cannabis-world.org/cw/picture.php?albumid=108&pictureid=963&thumb=1 (http://www.cannabis-world.org/cw/picture.php?albumid=108&pictureid=963)

Then I used the knife to trim away the excess foil by slicing it against the glass. (Quite a satisfying slicing action I should add.)

http://www.cannabis-world.org/cw/picture.php?albumid=108&pictureid=964&thumb=1 (http://www.cannabis-world.org/cw/picture.php?albumid=108&pictureid=964)

Then I put an identical electrode on the other side making sure to align the edges on either side accurately without too much overlap.

http://www.cannabis-world.org/cw/picture.php?albumid=108&pictureid=965&thumb=1 (http://www.cannabis-world.org/cw/picture.php?albumid=108&pictureid=965)

Aluminum is extremely hard to bond wires to, so I simply stripped some thin stranded wires and formed loops.

http://www.cannabis-world.org/cw/picture.php?albumid=108&pictureid=966&thumb=1 (http://www.cannabis-world.org/cw/picture.php?albumid=108&pictureid=966)

Then we stick them onto the electrodes with more aluminum tape. This should be fairly reliable, since the current is very low.

http://www.cannabis-world.org/cw/picture.php?albumid=108&pictureid=967&thumb=1 (http://www.cannabis-world.org/cw/picture.php?albumid=108&pictureid=967)

The easiest source of a modestly high voltage supply was from a cold cathode kit as sold for modifying PC cases. I got mine from ebay, and it came with two rather neat 12" (300mm) blue cold cathode tubes.

http://www.cannabis-world.org/cw/picture.php?albumid=108&pictureid=968&thumb=1 (http://www.cannabis-world.org/cw/picture.php?albumid=108&pictureid=968)

Most of these 12V cold cathode supplies are very similar inside. They have a simple push-pull transformer driver with feedback windings, and a high voltage output that is usually divided into two outputs using high voltage series capacitors which also serve to limit the current through each tube.

http://www.cannabis-world.org/cw/picture.php?albumid=108&pictureid=969&thumb=1 (http://www.cannabis-world.org/cw/picture.php?albumid=108&pictureid=969)

I cut the two output capacitors off since they interfered with the operation.

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And connected my home built corona plate directly across the output of the high voltage transformer.

http://www.cannabis-world.org/cw/picture.php?albumid=108&pictureid=971&thumb=1 (http://www.cannabis-world.org/cw/picture.php?albumid=108&pictureid=971)

When powered up, a thin line of purple corona should appear on both sides where the electrodes meet. If it's just a few patches of corona then you could try boosting the supply voltage up from 12V to 14V, although going higher may risk causing the high voltage transformer to fail internally. These little power supplies are not designed for open circuit operation like this, so don't push them too hard.
At this point you should be smelling ozone as a fresh smell a bit like chlorine bleach (also a strong oxidizer).

http://www.cannabis-world.org/cw/picture.php?albumid=108&pictureid=953&thumb=1 (http://www.cannabis-world.org/cw/picture.php?albumid=108&pictureid=953)

And here's the finished unit. It uses a standard 12V case fan to push air across the corona and mix the resulting ozone into the room air. The corona plate is attached to the fan with two bits of binding strip normally used to hold documents together. I put a blank glass plate in it to align the two bits, and then glued them to the fan with resin. A proper mounting clip would have been nice, particularly one that also made the connections onto the plate.
I powered the whole assembly from an ordinary linear plug-in power supply which was rated at 12V 500mA. I deliberately used an unregulated supply running at less than full load to try and nudge the output voltage up a bit for a better corona.
It works well and soon makes a strong smell of ozone permeate my large flat which means there's actually too much ozone being generated for an occupied area. The output can be tamed down if you reduce the voltage a bit. You should be able to gauge ozone output by looking at the corona in a dark room. For low levels it may even just be a few small patches here and there on the plate.
Alternatively you can run the unit on a time switch to cycle it on and off at various points throughout the day.

http://www.cannabis-world.org/cw/picture.php?albumid=108&pictureid=972&thumb=1 (http://www.cannabis-world.org/cw/picture.php?albumid=108&pictureid=972)

I added a 100 ohm 1W resistor in series with the fan I used to make it run quieter at the expense of airflow. This is only needed if you want to use the assembly in a quiet area where the whoosh of the fan could cause annoyance.
Although this unit uses high voltage it is at low current and high frequency, so if you should make contact with the high voltage side it is not really dangerous. Do keep in mind that if anything goes wrong then the high voltage could arc and cause sustained smoldering of whatever failed. As such, make sure that the unit is not used near anything flammable.

[hays]

looks great i would like to give it a bump.

[Green Supreme]

Sorry to be a negative nancy, just thought I would remind folks that excess ozone causes perforations in human lung tissue. Be safe. Peace GS

[hays]

bump

[vapor]

great thread!

[Flyer]

My ozone generators go straight to exaughst. I do not use any carbon filters what so ever, only ozone. I use very small amounts to kill pests and it is the only thing that will kill fungas gnats completely that I have found.

A good rule of thumb is that if you can smell it, its too strong. I get slight wiffs of it now and again and thats ok. Besides, it will keep GS out of your grow room! :muahaha:

[memyselfandi]

just some info

http://www.senlights.com/lamp/ozon/ozon.htm