It's good idea. During my 15 years at Nainital, I used two Nicrome wires, a PVC pipe and mains 230V to kill bacteria. I worked on XRF coating thickness measuring equipment. The high voltage generator of X-Ray tube was SMPS (TL 3842) based and they used voltage doubler circuit. The other possibility is to use (adopt) commercially available air ionizer HV power supply. Chinese make ionizer available from Rs. 400/- onwards.

Blumlein HV pulsers are very big in size and can generate 100kV to 300kV with 100A current in just few hundreds of ns duration pulses. This is something I will like to try to design for cleaning water for the entire city or at least the drinking water supply for a small town where I live.

Mr. Subramanyam,

We need to respect the basics of :

Internal Impedance of Generator(any type)AND

Impedance of LOAD

Please remember that the water bath has near-zero Impedance at nanoseconds.

That will mean Near zero Transfer of energy!

mikemahant@hotmail.com

There will be impulse current flow through water running to 100s of amps is a fact. Water then will get charge like a capacitor with internal field gradient enough to kill the pathogens with about 100kV/cm electric field. In short pulses even though current is very high, water does not heat up as total amount of energy is low. pathogens experience high potential gradient in water and their lipid membrane breaks open and external fluid enter the cell core and kills ts.

There are by now few thousands of research papers on it and was also part of the NASA workshop in 2003 or near to that time. This process is better than ark discharge process which ionizes the media and radicals kills the pathogens. radicals may be unwanted thing in the last.

While this technology of high voltage impulse field in food disinfection process now have become a usable technology, it has many advantages over Gamma Radiation, Ark Discharge and Chemical preservatives.

Apple juice with this technique is easily disinfected.

About 10W energy may be required for 1L volume of apple juice to disinfect using this process. In India we pay INR 4 for 1000W per hour power use. In $1 we can disinfect / sterilize about 1000L of apple juice.

Well, this is certainly one of the more interesting threads. My experience in designing special-application (and humane I might add) electrocution devices is in animals much larger than what you are proposing (with a voltage a lot lower).

I would suggest that initially you keep your experiments very small scale (like a petri dish). This will certainly help if (when) you have to redesign (altering voltage, pulse time, multiple rather than single pulses, etc), and will give you much more flexibility. Liquid conductivity may cause you problems (such as repeatability), so don't forget about it. I am not too sure about what voltage is necessary to break down the organic pathogens (viruses, bacteria). I have a feeling that you may have to reduce the distance between your plates considerably to get a voltage high enough across the tiny bacteria (1mm down to about 1um) and viruses (0.3um down to about 0.02um) to kill them. Don't forget too that if they are side-on the voltage across them will be less in many cases (due to them being narrower).

I don't know how far you are in to your research (I will assume early just in case) but I would suggest first starting with learning about what you want to kill (always a good start), and then the medium you want to kill them in (especially the way it acts when voltage is applied, and when it has other compounds mixed into it).

How are you planning to monitor the results?

One final point. Zapping water is all well and good, but take special care when trying it on liquids like apple juice. You may find that you breakdown or alter the organic compounds in it, damaging the flavour or making it toxic. I would advise against trying to sterilise juices and just stick with water (atleast for now) as it is complicated enough as it is (especially if the process works as you will have to thoroughly prove safety and repeatability).

Keep us up to date with your experiments and findings. I will do some further research into the subject so I may be of more assistance. Just yell out (well not literally) if you have any problems or questions.

This idea is basically for all types of food items to sterilize the food after production and before packaging or in packaged form. Few items that need this is juice and bread. We often find bread gets fungus and juice is full of pathogens and more harmful than doing any good.

This experiment is funded by the Government and is for large scale production units. Test data are available all over the world on the effect of HV pulse shock to pathogens. There is no plasma generation and there is no great breakdown of fluid to cause massive damage and pulse current is not going to cause any temperature change. In my experiment there is no DC current and only capacitive field formation using insulated electrodes is used. In this experiment we will look for the radiacls also that get formed and will keep them to minimum.

This is an emerging field and easy to use technology, it can reach the entire world to make it safer.

I came across this article in Journal of Food Process Engineering - Blackwell Synergy

I will like to thank the Journal in advance for this article reference here.

INACTIVATION OF ESCHERICHIA COLI IN SKIM MILK BY HIGH INTENSITY PULSED ELECTRIC FIELDS

• O. MARTÍN¹¹Food Technology Department University of Lleida Lleida, Spain,
• B.L. QIN²²Department of Biological Systems Engineering, WA 99164–6120,
• F.J. CHANG²²Department of Biological Systems Engineering, WA 99164–6120,
• G.V. BARBOSA-CÁNOVAS²²Department of Biological Systems Engineering, WA 99164–6120⁴⁴ Author to whom correspondence should be addressed. and
• B.G. SWANSON³³Department of Food Science and Human Nutrition Washington State University Pullman, WA 99164–6120

• ¹Food Technology Department University of Lleida Lleida, Spain ²Department of Biological Systems Engineering, WA 99164–6120 ³Department of Food Science and Human Nutrition Washington State University Pullman, WA 99164–6120

⁴ Author to whom correspondence should be addressed. ABSTRACT

The inactivation of microorganisms is the most important function in the processing of milk and dairy products. Traditionally, this purpose is realized by thermal treatment, but heat produces alterations to flavor and taste in addition to nutrient loss. The high intensity pulsed electric field (PEF) treatment should be a good alternative to heat because demonstrations have shown PEF can reduce the Escherichia coli survival fraction in aqueous solutions and model foods. In this study, PEF treatment was found to inactivate E. coli in skim milk (inoculum 10⁹ CFU/mL) at 15C. The microorganism inactivation satisfied Hülsheger's model following a first order kinetic for both the electric field intensity and number of pulses when skim milk inoculated with E. coli was treated in a static or continuous flow chamber. PEF treatment in a continuous system when the critical electric field (E_c) and minimum number of pulses (n_min) were 12.34 kV/cm and 2.7 at 30 kV/cm and 30 pulses (0.7–1.8 μs pulse width) inactivated more microorganisms than in a static system. It has also been proven that increasing the pulse duration increases the E. coli inactivation. The inactivation of E. coli using PEF is more limited in skim milk than in a buffer solution when exposed to similar treatment conditions of field intensity and number of pulses due to the complex composition of skim milk, its lower electrical resistivity and the presence of proteins.

i am not an electronic man but i am definitely involved in purification of water for potable purpose. i am involved in rainwater harvesting which may not need filtering/cleaning. but for acceptability by people for drinking, some device(gimmick?) need to be employed.

you must be aware of stun gun, a self defence device, which on contact with the target gives a surge voltage of upto 200000 volts, said to be harmless. this is available for less than 200 dollars. i can get one for you if you like.

i would be eager to know the outcome of your trials.

No, not enough power to clean water. That stuff charges small capacitor only to give small shock in local area on the body. We need to give shock to all that is present in 1000L tank and finish then in just less than a micro second. Think of doing it in a swimming pool with so much of water in it.

Perhaps in a glass of water, this thing may work but will require some modififation.

Long ago I invented this electrostatic discharge GUN and it was published as design idea in EDN magazine. Search results for my name at www.edn.com resulted in this design idea. You can search my name to get more ideas.

http://www.edn.com/archives/1996/091296/19di1.htm?q=shyam+sunder+tiwari

got it. perhaps, it was like,as they say in my local language, 'teaching tirumantra to guru' guru both real and figurative. i would be interested to visit and know about your invention on the site indicated by you. so, i am back in square one - having to depend upon conventional filtration for rain water like sand, activated carbon, nano filtration, reverse osmosis, ozone, uv etc. etc. i hope you will come out something practical on the scale required for my applications.

Sedimentation of floating mass and filtration process for unwanted ions are still OK. This process does what UV does and in some what better way. For food items this one works well as electric field can be created across a solid mass like bread. Hence, now on wards the dielectric media is your food and HV pulser does the killing job of pathogens in few pulses of 100ns to 1000ns each pulse having 100kV/cm electric field. Short pulse do not move ions to large distance. Plasma processes generate avalanche and chain of ions which is bad. Here just short pulses separated from each other with little average energy. Hence if you use this in your coke or apple juice it will not warm the juice and you will have apple juice + dead pathogen protein juice to drink. That is what you have with UV exposure also. Have a nice time.

Hi- want to wish you luck and when you do get it up and running maybe consider another app as being a way to sterilize liquids. some cant take heat or other processes. I may in the fyture need to have that ability for medical purposes.

Thanks

Yes, it is not just water, but all types of food items are being put to test on this technology. Only highly solid like potato etc have to go through gamma irradiation and for medicine gamma is the best thing to do as you can expose the medicine in packed condition. This process will not replace the gamma process but is useful in a limited way for some food items only.

Dear Shyam

It´s great to know of hew water purification technologies like yours, in my country 90% of all rivers are already contaminated by citys sewage and an echonomical mean to clean them would be very wellcome. I comercialize industrial technologies here in El Salvador and please let me know when you are ready to market.

A friend from US a few year ago started a company to clean soil from pathogens by running two electrodes pulled by a tractor+generator and sterilizing soil by an electrostatic flow but didn´t succed. Maybe you r system could also be aplied for soils! in agriculture sometimes is very hard to get rid of some pathogens and your technology would help clean our enviroment by no tusing some chemical products, and increasing production. The company name was Electrofrac.-

It is not good to temper with soil as bacteria in soil are often nitrogen fixer for plants and if you kill them then plants will not grow. One way to remove or reduce the pathogen is tilting the soil in summer and leaving it to expose to sun for a while for few months and then using it. Human excreta is often heavily loaded with bacteria and hence not a good fertilizer unless pathogens are destroyed. Water sterilization and rice farming may also be the cause of greater pathogen in the zone and hence crop changing may be ideal.

We had an experimental Garden called a Gamma Garden. This experiment may be useful for you so please contact the writers of the papers below. You can easily take help from www.barc.ernet.in the Government of India Atomic Research Center for easy removal of pathogen from agriculture and food items. They may sell the entire facility to your Government. I am afraid they will not give it to individuals due to safety concerns. I was one of their scientists not directly involved in this project but have knowledge of it to some extent. These doses given to plants and soil are fatal for man. Hence, there is concrete wall all around the garden and control over the radiation source to make it safe for use. Dose also kills the insects and products are free from bacterial contamination, and generally grow larger than normal size with much greater yield. In India, we use this technology at limited places even though we have all resources, millions of trained scientists. Funny thing is we are not for money and if your Presidents gives a call to our Government, then most likely can get it as a gift and free training to your scientists.

This information is copyright of Journal of Food Science and is placed only for reference for further reading from the Journal. I will like to thank them in advance.

Microbial Decontamination of Tea (Camellia sinensis) by Gamma Radiation

• B.B. Mishra¹¹The authors are with Food Technology Div., Bhabha Atomic Research Centre, Mumbai-400085, India. Direct inquiries to author Sharma (E-mail: ksarun@barc.gov.in).,
• S. Gautam¹¹The authors are with Food Technology Div., Bhabha Atomic Research Centre, Mumbai-400085, India. Direct inquiries to author Sharma (E-mail: ksarun@barc.gov.in)., and
• A. Sharma¹¹The authors are with Food Technology Div., Bhabha Atomic Research Centre, Mumbai-400085, India. Direct inquiries to author Sharma (E-mail: ksarun@barc.gov.in).

• ¹The authors are with Food Technology Div., Bhabha Atomic Research Centre, Mumbai-400085, India. Direct inquiries to author Sharma (E-mail: ksarun@barc.gov.in).

Abstract

ABSTRACT: Processed dry tea leaves are prone to microbial contamination during post-processing handling and storage. The dry tea leaves may thus carry bacteria and fungi of potential health risk to consumers. Also, during storage under high humidity, absorption of moisture may encourage fungal growth and result in caking of the product. Gamma radiation processing was tried as a method for microbial decontamination. A radiation dose of 5 kGy was found to be effective for this purpose. No significant effect was observed on total phenolics in radiation-processed tea leaves. The antioxidant and biological properties of tea such as free radical scavenging activity, inhibition of xanthine oxidase and lipid peroxidation, and superoxide and nitrite scavenging activities were not affected due to radiation treatment within a dose of 10 kGy. The antimicrobial and sensory properties were also unaffected by the radiation treatment.

Thank you Shyam

This is a great site, and congratulations for the service your country offers, I found a lot of very interesting technolgies but the one we are talking now, but I mailed them asking for information. Thank you

I hope it can be used for water, although irradiation here, though is used by some industries, is hard to sell as an option due to enviromental matters, or ignorance!

When my father used to plant rice he used to tilt the for solarization, you are right.

Is there a company that comertializes water irradiation technology?

In India all radiation sources are regulated through Atomic Energy regulatory Board (AERB). They follow the International Atomic Energy norms. They are only authority to produce and sell radiation sources and also account for these each year wherever these are in use or stored. BARC also provides WHO supported training for radiological Physicist who are allowed to handle radiation sources. I was trained by them in 1974-1975 for full one year and that also resulted in a degree certificate.

Hence, all purchase of sources in India is through Isotope division of BARC to an agency which has followed their norms and has trained person to handle the radiation sources. Gamma radiation sources are transported in heavy lead shield with lots of care. These are much larger sources than one used in cancer radiation therapy.

Cs-137 or Co-60 radiation sources are used. If you have a valid company with all that they want on papers, then they may give you the system. Often your own country will ask so many questions as you are handling lion in a cage. Radiation sources are very dangerous so none of here play with them else lots of us will be in hospitals with no cure. I do not know the standard of this kind of technology usage in your country. Perhaps cancer hospital doctors can tell you much better as they must have something like this one at smaller level. They may also have accelerators which are different in technology but generate a bean of accelerated particles. We use them for cancer therapy but not in agriculture so far.

Food irradiation using radiation source is now very common. That kills pathogens inside the fruits and also on the surface. Radiation source goes into water tank when not is use and the entire building is made radiation shield for public.

I have some experience with radiation, from the folks perfomring NDT in my welding projects and they are qualified to handle this materials.

Do you have any idea of echonomical matters on irradiation for sewage? it would be interesting to teach my goverment to use it.-

Are you producing radioactive materials in India? do you know who to contact?

Let me answer your questions one by one

Sewage treatment using radioactive ionization process is very much possible but who is going to put the bill? In Chennai, Madras Refinery Limited MRL is taking sewage water of Chennai city and processing it to make drinking water with number of processes. I have looked at their plant and it starts with sediment removal first in large tanks, then trapping of small particles in Calcium Oxide and then reverse osmosis for mineral removal and finally UV for bacterial killing. Only thing here can be replaced is the UV to Ionizing Radiation. The only advantage will be zero power requirement for generating radiation but will also call for industrial safety and special room design to shield the radiation. Perhaps the radiation source can be under ground and pipes can pass through it to receive radiation exposure. Even an entire water tank can be exposed to radiation by keeping the radiation source in the middle.

Unless you use the water, the cost will be prohibiting type.

BRIT in BARC manufactures and sells the radiation sources. Radiation sources are under control of Isotope Division of BARC. If you do not know to whom to write then write to the Director Board of Radiation & Isotope Technology (BRIT) a unit of the Department of Atomic Energy, Anushakti Nagar, BARC, Mumbai 400 094.

You can also visit

SCTIMST, Thiruvanantapuram

RVNRL, Kottayam

These two organizations have Irradiation facilities developed with the help of BARC near your place.

If you have more questions then write to me.

I agree and really don´t know what the cost would be, but my idea was to treat the whole flow, without building a complete treatment plant. So this way all the sewage without bacterias could be sent to the rivers so there is no contamination for those using the water downstream or using it directly for agriculture purpose and with fertilizer added. So an irrigation field could pay some of the investment or all of it? and the health improvement of downstream villages, so the goverment of the contaminating town could provide another part of the cost.-

What would the cost be for a certain flow?

Any way, hurry with your system that is a lot simpler to maintain !!!!!!!

You can't do it for a river. Micro organisms are food chain for other bigger organisms elese this world by now should have flooded by them. You need not too much worry about them in nature. All you have to do is to make the drinking water OK. Perhaps the drinking water for live stock may still be a problem as they will be fed unprocessed water. That is one way pathogen survive.

. M/s Ardee Hi-Tech Pvt. Ltd.,
9-30-4, Balaji Nagar, Siripuram,
Vishakhapatnam – 530003 (India) Phone : +91 0891 2702852/2702853 Fax: +91 0891 2755507 Email: gsnmur@sancharnet.in M/s Genesis Power Equipments Limited.,
7/1, Srinivagalu Main Road, Eg Pura, Vivek Nagar Post,
Bangalore – 560047.(India) Phone:+91 080 25712727/13514 Email:gpel@bgl.vsnl.net.in

I tried to contact this 2 companies for water treatment equipment but it seems the mails are wrong,(from BARC site). do you see anything wrong with the adresses?

Search for company name on the net putting India along with their name. Their email service may be old and not working. Here in India many service provider for email close very often and some time people close their email due to junk mails poring in. I agree that making contact with government people in India on net is absolutely difficult. many organizations also inhibit external direct contact. However phone lines often work. Just use them.

Why not buy one of these and reverse engineer it?

Press Release

Release date: August 15, 2006


PEF Sterilization System Produces No Chemicals, Heat or Byproducts



An industrial-scale system that utilizes PEF (pulsed electric field) technology, resulting in >5 log bacteria kill for food pasteurization and water purification applications, rather than harmful heat or chemicals, is being introduced by Diversified Technologies, Inc. of Bedford, Massachusetts.

Diversified Technologies' PEF System is a non-thermal, chemical-free, all solid-state system which passes liquefied food products or water through a chamber and subjects it to brief pulses of very high voltage. Engineered and built to customer requirements with up to 10,000 LPH throughput, this industrial-scale sterilization system produces >5 log bacteria kill.

Unlike heat processing in food applications, Diversified Technologies' PEF System does not alter the flavor of foods or juices and requires much less energy to operate. In water purification applications, it eliminates the need for chlorine, ozonation, and other chemicals. Power levels are offered from 25 kW to 750 kW, with full control over pulse and frequency.

Diversified Technologies' Industrial-Scale PEF Systems are priced from $250,000.00, depending upon configuration.

For more information contact:
Diversified Technologies, Inc.
Michael A. Kempkes, VP of Marketing
35 Wiggins Ave.
Bedford, MA 01730-2345 USA
(781) 275-9444, x211 FAX (781) 275-6081
e-mail: kempkes@divtecs.com

Buy, yes; engineering, yes; reverse engineering, NO.

It is all right to peek but bad to poke. Let us respect others hard work also.

It is still a field of research and lot of things will come up in time. Some good new and some not so good news. Let us do things and contribute our knowledge to the world along with that of others. As we discuss here, we also share knowledge with others with a clear aim that some of you will also pick the ideas and help the world. I don't mind sharing my ideas with others because I care for the entire world and not just myself. I will not last much but my good will may just be here here for many to follow. That is what I care.

So, let us think collectively and come up with great idea of our own. We learn from each other, as we learn from our own experiences. I enjoy doing it in my way.

I have few 15kV HV power supplies and some HV pulsers so will kick off some pathogens from the experimental slide under the microscope next week to see then getting finished with 100kV/cm electric field. I also know the problems as in air it takes only 40kV/cm to spark and any air bubble in the water going to have a good ark discharge.

I did some of these experiments some 25 years ago with hope that I can make the trapped electrons in LiF to kick off other electrons under such electric field. I was wrong and experiment failed even when I placed the LiF crystals inside transformer oil as micro bubbles caused spark and that generated vacuum UV and finally registered a signature in the LiF crystals. I did get large signal recorded in the form of Thermoluminescence but it was all from a failed experiment. I discovered by accident that I can record spark information in LiF crystals and can retain it for 1000s of years.

I am not so worried about how it will go as there are many more people doing the same thing and they all must have good reason and we all have good reason to have this technology. We want sterilized food at almost zero cost and ns time. So, let us do it and do it now.

There are many things we can learn from India, like Gandhi getting independence from England without violence.

The great MK Gandhi belonged to the entire world and his philosophy will remain the greatest for ever. If you like him then he is right there where you are. Many people in the world learnt from him a new way of living. Many preached before and going to preach all the time good things but there are some who lived for it and though it looks impossible that there was this great man, it just happened that way and he made it for all of us to experience it to some extent. He lived that way for you as well.

If you want to buy that then it starts at $250,000. You can pull a train out of that for sure. I will like to design a bit lower cost device. Those MOSFETS and IGBTs are IXRF, DEI, Behlke etc. They are the only company in the world busy doing such things. Who else will make those 60kV 100A fast switches. I am going to buy all those parts all right.

Hi Shyam,

you mentioned the bubbles may be a problem: may be these can be prevented by putting some pressure on the fluid, this will not eliminate but minimise the problem.

Next: if you want to generate water waves (tidal or else) that amplify passively: this is done in letting the wave run into a narrowing channel. As the energy will not be dissipated the amplitude is amplified as the channel width is smaller and smaller.

Tidal waves go up by a factor of 30 by this mechanism and more is possible but no natural cost is existing that will perform this.

Similar technical solutions are the matching shapes (exponential) in piezo driven loudspeakers and piezo grinding and drilling of gemstones.

What is the analogon in electrical transmission lines?

I suppose if you build a transmission line with a variable C (and may be a variable L?) this will act similar (but also different as the line transformer action is altered.

This for shure can be answered by a high frequency specialist or /and calculated by some FEM program.

The realisation (my best possible guess as being a mechanical engineer) will be a coaxial line with continously varying thickness of the (teflon, quartz or sapphire) insulator.

The insulation getting thicker will yield lower capacitance and thus higher voltage per stored energy.

Additionally you can get rid of the high voltage excitation and change to high current excitation by using a quarter wave length - no idea how this will change by the variable insulator thickness. In old antenna books I saw once a continuous variable matching device made of a conical metallic part, this was either in a book from Meinke-Gundlach or from Rothammel.

Is there any information on virus killing too?

Good luck

RHABE