Decontam with UHP water jet

[canduman]

Greetings to all of you,
I am looking for info regarding the use of Ultra High Pressure water jet application in decon work.
Thank you in advance
canduman

[Already Gone]

We do it all the time.  It is called hydrolasing. (a reference to the water jet being focused and intense like a laser beam).  Mostly we use it inside refuel cavities, which you don't have.  I did use one once at Pickering in the irradiated fuel bay, but it was all underwater.

Some things to consider:
The water spray will create a mist which can often carry contamination aloft and deposit it outside the area.
The jet can be dangerously powerful.  It can cause injury if not used properly.
It can take off more material than you might have intended.  If the surface is painted or coated, a lot of that will be removed if you aren't careful.  Some of it will be removed even if you are careful.
If you get a little Karcher at Canadian Tire, it may not have enough power to do the job on a large area, but it could do quite well for smaller things like tools and parts.
If your machine has a steam option, do not use it unless you need to remove oily or greasy contamination.  Otherwise, it won't help you clean and it will increase the airborne contamination a lot.
If you are using it to clean parts or tools inside a glove box, it is a really effective method for getting off loose contamination in tight areas, but CO2 pellets or sandblasting are better for removing fixed.
They use incredibly high volumes of water, thereby increasing your liquid rad waste volume and eating up your pure water supply.

It would be helpful to know what you intend to use it for. 
I hope this helps.

[canduman]

I am working on the design of a decon cell utilizing UHP water jet ( Hydro lasing ) and Dry Ice blasting as the primary. Water pressure is approx. 32000-55000 PSI and flow rates around 1.5 -3Gpm. There are different jet configurations depending on application, fixed jet , rotary jet and so on. Aside from loading and unloading the process is fully automated or manual via PC using a gantry type XYZ table. Water and air are filtered for recirculation thus reducing waste.   

[Already Gone]

Wow, sounds like there is some money behind this rig.  What are you going to use it for?  An American plant would never shell out the cash for that.  They have to make a profit without government subsidy.  Well, mostly. 
This setup is more like something a vendor would have to decon their equipment at their own facility, or maybe something you would find at a government installation.

[Jr8black3]

 I second Beer Court. WOW!! Sounds more like a cutting tool to me then a decon tool,,, 32,000-55,000 PSI @ 1.5-3 GPM,,, Thats wicked......

Good luck, I hope you don't cut your plant apart if that thing gets out of control......

[KevsHarley]

I worked with OLD ARC when we did alot of water jetting. We used portable Diesel engines to and we shot water at 50,000 psi. We did everything from Roters, to the coal burners in the coal plants. It is a messy job and alot of water to dispose of. The pressure would cut through a foot of steel in about an hour if you left it in one place. You had to hang on to the guns so that they didn't get away from you. They would almost knock you to the ground when you pulled that triger. There is still a couple companies out there doing this form of work. Keith Blanton is still running the show last I heard, but not sure what company he was with the last time I saw him. I think they are still out of Georgia. Good Luck and Please becareful.

[Jr8black3]

Yes please becareful, your messing with a beast that can bite you so fast you don't have a chance... I learned all my hydolasing experince from the great old Green Machine ( HYDRO) and some with ARC and Bartlett.. OOPS I forgot the old PSESI....If anybody remembers what happened to Mark Mathews @ DC cook knows how fast it can happen.....I prefer to walk away from a job with both my nuts!!!!

So be safe, and watch your co- workers back, make no mistakes!!!!!

[canduman]

Yes there is money behind this project and for a good reason. Consider the cost of disposal \ storage of one Cubic meter of solid waste @ 40K$ A POP. Lot's of incentive to free release decon. NO government subsidy here either.

[Already Gone]

Gee! After 23 years working in Nuclear power, I finally get a lecture about the expense of radioactive waste.  I almost made it to retirement without gaining that valuable nugget of information.

Yes, I'm being sarcastic.  My point was that the machine sounds expensive, and profit-making utilities rarely make the investment when they can just hire the work out to a contractor.

Yeah, live in the dream world where the OPG is not being constantly fed money by the taxpayers.  In your case, however, it is a little different.  The last I read was that British Energy had to return the Bruce to OPG because they couldn't afford the lease payments any longer.  This was about the same time that the  Crown had to bail them out of a financial jam to the tune of $1billion U.S.

So the very existence of the station is due to the generosity of TWO governments and the bloated beaurocracy of TWO government-owned companies.

Wish I could get the Feds to buy me a new decon machine.  The cheapskates here make us launder and reuse mopheads.  That's about as high-tech they're going to go.

[PWHoppe]

There are still companies that do water blasting. I would suggest Master-Lee/Hydro-Blast Inc. out of N.J. They have alot of experience and the equipment to do what you want. They are comprised of many of the old hydo boys and are a good group of folks. If you need contacts e-mail me.

Also as everyone here has said this is something you want to be very careful with, or you may not end up with both of your nuts, that wasn't a joke but a real life scenario. I was there.

[canduman]

Sorry, no lecture intended. I am way past that after 30 years in nuclear. Commentary is great, keep it going. That news on government and British Energy ak. Bruce Power never got here, must have gotten frozen on the way north. How about some more detail on that. 

[Already Gone]

This is way off topic, so I'll just say that it was on the grapevine at OPG when the news broke that BE was in deep financial straits.  The British Government did have to bail them out, and they were talking of divesting themselves of their interest in North American nuclear plants.  So, if they're still leasing the Bruce, it is at the expense of the British government.

But let's get back to your machine.  How big is it?  Are wee talking about a booth, a room, or just a little box?  Is it for tools only, or for larger equipment?

I take it that this entire operation is remotely controlled, taking some of the hazards away.  Still, I would propose  "dead-man" switch to keep the operator from entering with pressure available to the jets.  There have been lots of stories of people who defeated safety interlocks to speed up the work, only to hasten their own deaths.

[slattmandu]

I started this nuclear adventure shooting water for the "Green Machine". That was of 10,000 psi variety and then after working a job for ARC. I recieved the offer to play with ultra high pressure in Newport News shipyard. I was aware of the dangers of high pressue water blasting. I was 1 of the cleanup crew when Mark got hurt at Cook. So after arrival in Va. and completion of 0 hrs of training I was shooting 40,000 psi of water. Very effective removing rust from steel in prep for paint. The recoil of gun was about the same as 10,000 psi at 6-8 gpm. We did have 1 injury in Ballast tanks, tech manually freed up jammed rotating head on gun and shot a jet of water thru 1 finger almost severing other 3 fingers on that hand. So hopefully you can include some failsafe guard into the design of your UHP Booth. So operators don't leave behind pieces and parts that were once attached to thier bodies. 

[bikerdad]

I presently do High Pressure Water Jetting and work for 3 different companies that do this type of work. They also do cryogenic cleaning, dry ice, and can give you names of several individuals that can help you out. Feel free to email me.
Bikerdad

[canduman]

OK. Back to the machine. Safety first. Considering human nature and taking all the horror stories in to account it is my goal to include some smart safeguards into the design. Key interlocks are part of the control circuit that drives the water jet. The working envelop of the table is 3' X 6 ' X 3' as in XYZ. Of course the beast is totally enclosed. Defeating the safety interlocks will be a challenge and as we all know a lock keeps only an honest man out. There will be training of a dedicated crew. Water and air filtration is included to minimize secondary waste. Water is recycled and some of it evaporated reducing volume to be managed. 

[DecommMan]

I would have a problem with all the secondary waste - water and grit both - this beast creates not to mention the safety issues.  Disposal is too cheap for us to get too excited about decon anymore at many Govt sites. 

The Japanese have done lots of cutting of concrete bioshield concrete with AWJ and have also done and are doing lots of work in laser cutting.

[glhotdogs]

Hi I'm a first time poster.

Sory to butt into the conversation but it kinda fits and I didn't know where else to post.  I did post on the geneal board too.
To be upfront with you I am not a "nuke handler" I am invested in Universal Ice Blast Inc.  They reportedly delivered two Ice Blast machines to Bruce, in 2002.  This is not the Dry Ice method.  This was a new method which seemed to have the bennifits of lower water usage and more scrubbability do to the abrasiveness of ice over water. I was wondering if anybody out there has had any experiance or heard of the machine? Thank you in advance.
The website for the company is below.  They claim to be making inroads in the Nuclear industry.  This is a small company that is struggling and I am trying to do some research to see if they are doing what they say.
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http://www.iceblast.net/
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Regards The Hotdog

[DecommMan]

Why does this project stand?