Gents, what is the best type of OWS you have used? Any that really stand out as being trouble free, and low maintenance? Besides boiler type that just steam the water out. Thanks in advance.
[QUOTE=Fraqrat;142388]We use these…
http://compasswater.com/productmenu/oilywatermenu.html[/QUOTE]
Hmm. If you like yours, I’ll pass this info on. The ship I’m on now has a Coffin model with a membrane. It is awful. We can’t use it to process water and are now pumping bilges to the waste oil tank (oily waste is full). We have rigged a hose to the sounding tube to do this.
Wartsila. Set up right they will process almost anything.
[QUOTE=Yeasty McFlaps;142387]Gents, what is the best type of OWS you have used? Any that really stand out as being trouble free, and low maintenance? Besides boiler type that just steam the water out. Thanks in advance.[/QUOTE]
I’ve had good experience with GEA’s ows system. If it’s only oily water, the Coffin style seem to work well. The problem I’ve run into is that if there is anything else in the water besides oil (dirt, silt, rust, carbon) the Coffin just can’t handle it, the eye thinks it’s oil and sends it back to the tank. It doesn’t really have any way of removing anything other than oil. On one ship we tried a fancy pre-filter setup for the coffin but the company axed that idea. We’d get an hour or two of running out of a filter before it would clog. At a couple of hundred bucks an element, four elements in the prefilter, it adds up quick. They were in the process of trying out a different prefilter using a sand media around the time I left. We found the problem with that to be that the sand settled in the bottom and basically turned to concrete from the vibration of the slow speed. I left shortly after so I’m not sure what the next step was.
The GEA system on my current ship is a small centrifuge that works great. The only time it’s had issues is when someone dumped a bunch of soap into one of the bilges which caused the water to suds up badly. The other issue is in the winter time when the ship rolls a lot more. The overboard opening tends to come out of the water which causes big fluctuations in the backpressure on the centrifuge. Oil, silt, carbon, rust, etc, all get taken out and the two OCMs rarely get above 0ppm. Yeah, there are two OCMs, one on the unit and a separate one locked in the whitebox. Either one of the OCMs can redirect water back to the tank.
Great input guys thanks. I like the idea of a centrifugal type, I wonder if an old fuel centrifuge could be converted to process bilge water, I’m not sure if its in the cards to get a new unit.
Coffin/Compass are not that good. I have nothing but problems with them. We had a BOSS 10 that worked great but we had to change the clay and sand in the filter often, and it was a pain in the ass. But, it was a good OWS.
[QUOTE=Louisd75;142432]I’ve had good experience with GEA’s ows system. If it’s only oily water, the Coffin style seem to work well. The problem I’ve run into is that if there is anything else in the water besides oil (dirt, silt, rust, carbon) the Coffin just can’t handle it, the eye thinks it’s oil and sends it back to the tank. It doesn’t really have any way of removing anything other than oil. On one ship we tried a fancy pre-filter setup for the coffin but the company axed that idea. We’d get an hour or two of running out of a filter before it would clog. At a couple of hundred bucks an element, four elements in the prefilter, it adds up quick. They were in the process of trying out a different prefilter using a sand media around the time I left. We found the problem with that to be that the sand settled in the bottom and basically turned to concrete from the vibration of the slow speed. I left shortly after so I’m not sure what the next step was.
The GEA system on my current ship is a small centrifuge that works great. The only time it’s had issues is when someone dumped a bunch of soap into one of the bilges which caused the water to suds up badly. The other issue is in the winter time when the ship rolls a lot more. The overboard opening tends to come out of the water which causes big fluctuations in the backpressure on the centrifuge. Oil, silt, carbon, rust, etc, all get taken out and the two OCMs rarely get above 0ppm. Yeah, there are two OCMs, one on the unit and a separate one locked in the whitebox. Either one of the OCMs can redirect water back to the tank.[/QUOTE]
That is exactly what is going on with these coffin units. Clog and send back to the tank or trip offline. In fact, they got a plastic 55 gallon drum and some hose and fittings with the intent of making a “settling tank” pre-filter but that idea has been tabled for the time being. I think they are approved for a replacement unit. I’ll be gone long before then, as in days from now.
I’ve had the best experience with the Boss units which utilize a clay/crushed rock separating media contained in a separate fiberglass vessel. Turn it on and turn it off. It’s that simple. Change the media out once per year. I’ve worked with coffin spir o lators on many different vessels and they are compete junk. The membranes are constantly getting fouled and they’re really expensive to recondition or replace. Boss is where it’s at.
[QUOTE=catherder;142449]That is exactly what is going on with these coffin units. Clog and send back to the tank or trip offline. In fact, they got a plastic 55 gallon drum and some hose and fittings with the intent of making a “settling tank” pre-filter but that idea has been tabled for the time being. I think they are approved for a replacement unit. I’ll be gone long before then, as in days from now.[/QUOTE]
The settling tank pre-filter might actually work out. We ran the coffin without the elements in the prefilter when we ran out of 'em. It worked surprisingly well and we ended up with a pile of sediment that got shoveled out on a regular basis. The C/E was concerned that we might be accused of not running the machinery as designed by leaving the filter elements out so we stopped doing that and got the sand contraption. The C/E’s concerns were based off of a COI where we had two dickhead coasties put us through the wringer over the OWS and just about everything else on the ship. The class inspector was aboard at the time and even he was getting pissed off at them. That’s a whole different story though.
As far as converting a fuel purifier, I’m sure it’s possible but I don’t know if it would be cost effective. All of the centrifuge OWS’s I’ve worked on have been small. The last one was the same size as the OSC-5 lube oil purifiers that we used on the aux generators. A lot of the parts were interchangeable but there were many minor differences. The OWS had no brass parts and additional ports in the centripetal pump chamber. I think it also used two piece gaskets on the annular piston. You’d be best off checking with the maker of the fuel purifier to see. I’ve got a hunch they’ll try to sell you a complete skid package.
Absolutely agree with socalsalt, the coffin world spir-o-laters are crap. Company installed new spir-o-laters on 6 of our vessel’s and within a month or two they had all been sent back to the factory. We reinstalled our old coffin world heli-seps while we looked for another replacement. From what I hear the brute/boss units are the way to go.
I like the boss units, but its a pain to remove and dispose of all the sand and clay, and it clogs quick if you have emulsion. Parts are also difficult, as the manuals don’t include a lot. I’ve used coffin type also, and they don’t clean the water like the boss units do. Anyway thanks for all the input.
Helisep works but if you can back flush it with hot water (media and tank) and keep the soap out of it you’ll be ok, the soap is the biggie! I knew a cme who’d wash the bilges daily and flush o/b saying if done daily it wouldn’t exceed 10ppm… you could eat out of those bilges! the ows didn’t work…govt. ship too!
Marinflocs.
Most OCM’s (at least the Deckma’s on the OWS units I have dealt with) will see dirt, soot, or rust as oil. I have seen sock filters added to the inlets of OWS to help with that issue. Some of the newer OWS have polishing filters for that sort of thing. I liked the ole Sigma units for simplicity but they don’t meet the latest standards. RWO units are pretty good.
Best I have seen is the sludge truck/barge you pump to. Second best is the boil off the water and burn the sludge in an incinerator type set-up used on car carrier ships. I have not seen an oil content monitor that processes cloudy water but maybe NASA has one. I like those scupper plug filters that look like a giant earplug but absorb any oil passing through and let the water go overboard. Sailed with one ows similar to that but the filters are expensive.
I recently had a Port Engineer installing an OWS and he caught me off guard with a statement he made. The crew was complaining about the suction pickup not being low enough in the bilge to be able to use the OWS regularly. The Port Engineer said an OWS is not designed to handle water coming thru it on a regular basis. So the crew is having to use a diaphragm pump to suck the oily water from the bilge, transfer it to dirty oil tank and then he wants them to circulate the dirty oil so the water can be discharged. I don’t recall ever seeing an OWS that wasn’t setup or designed to mainly process bilge water and dispose accordingly.
Has anyone heard of anything remotely close to this?
[QUOTE=Saltine;148365]Has anyone heard of anything remotely close to this?[/QUOTE]
It’s not uncommon. The last vessels I sailed had a “housekeeping” hose connected to the DO/stripping pump. Anything not picked by the fixed suction was stripped with the hose. It was pumped to the oily bilge tank for decantation. The water was pumped off through the OWS and oil to the DO tank
[QUOTE=injunear;148368]It’s not uncommon. The last vessels I sailed had a “housekeeping” hose connected to the DO/stripping pump. Anything not picked by the fixed suction was stripped with the hose. It was pumped to the oily bilge tank for decantation. The water was pumped off through the OWS and oil to the DO tank[/QUOTE]
I guess I should have clarified my statement. The OWS pickup is located pretty high, close to a foot (maybe higher), off of the bottom of the bilge. Basically, unless the bilge gets a substantial amount of fluid in it the OWS will never be used. On this particular vessel the OWS has never been able to be used for this operation due to the high pickup. To pump any fluid out of the bilge they are having to use a diaphragm pump.
[QUOTE=jimrr;145901]Helisep works but if you can back flush it with hot water (media and tank) and keep the soap out of it you’ll be ok, the soap is the biggie! I knew a cme who’d wash the bilges daily and flush o/b saying if done daily it wouldn’t exceed 10ppm… you could eat out of those bilges! the ows didn’t work…govt. ship too![/QUOTE]
Oh, I know who you are talking about…lol…he still does it.