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Frequently Asked Questions


What is the separator footprint area? And what frontside access is requried? The footprint areas are noted on our brochure. The front side access needed is only 600mm. 


Which type of pump do you use? Is suction height minimum 3-4 meters a problem? We utilize a positive displacement pump, capable suction lift up to 7.5 m. 



Are there any filters that need to be replaced to keep the unit running effectively? Yes, our filters may be needed when the oil density is high. However, Crystal is being used for 36 months on board a tanker of 330,000 TDW which crossed three oceans from the tropics/Equator to Cape Horn and no filter cahnge was needed during this period of time. This is due to the fact that the oil content in our 5th stage before the filter was so low (as low as 0.1 mg/l and consistently below 1 mg/l) that the filters became superfluos.
What type of maintenance needs to be performed on the units? The only moving parts are the valves and the air diaphragm pump. The valves require no maintenance and are guaranteed for 1 million cycles. The pump is a Husky air diaphragm pump which doesn’t require maintenance and has a 5 years warrantee, which is the best in the business. Maintenance has been minimal and during the  36 month period the separator did not require any maintenance as can be seen in the appended Vela testimonial.


If additional pump required (if more than 7 meters vertical from pump to tank), is this possible?  Yes additional pump is no problem at all.


Is the sludge removal. Mechanical or manual? It can be both!  Manual removal is standard, however for a slight fee we can include automatic.


System integration with the “White Box” or “Blue Box”?  Integration with a white box is easy and not a problem. For a small fee we can include it with our system.

Who certifies oil water separators for discharge? The International Maritime Organization (IMO) Resolution MEPC.107 (49) specifies a test procedure for bilge water separators and the removal of stable emulsions from bilge water in addition to the removal of oil. Adopted in July 2003, this resolution became effective on 1 January 2005 and applies to all vessels with new installations. Future legislation is expected to be even more stringent, requiring levels of oil in water to be further reduced to five ppm for discharge at sea, and to zero ppm in sensitive waters.

How much fresh water do we need to run the separator to do a back flush? Up to 40 liters for the 10 m3/h separator which is our largest unit, 2 liters for the 0.25 m3/h separator which is our smallest separator.

What are the operating pressures of the Crystal Sea?  Crystal operates with pressures of up to one (1) bar in the low pressure side. The separator is build to withstand pressure between 30″ Hg (vacuum) and 15 psi in the stages upstream of the pump and up to 45 psi in the stages downstream of the pump. The hydrostatic test is done at 1.5 times the pressure mentioned above.

Does the Crystal Sea meet Coast Guard regulations for overboard discharge?  Definitely. The Crystal sea separator meets IMO/MEPC. 107 (49) and USCG regulations. Not only do we meet Coast Guard regulations but we exceed it by more than 90%. We also meet all classification standards as well.

Can you guarantee 15ppm overboard discharge even with emulsified oil?  Absolutely! The term emulsion means “the mixture of two un-blendable mixtures.” Our Crystal Sea separates emulsified oil with ease and we guarantee 15ppm.


What savings can I expect from switching to Crystal Sea?  A customer can expect 90 % savings and even more compared with competitor OWS systems. Our units have no internal moving parts, require no costly chemicals, have no mutating microbes, in most cases don’t need any filters, consume very little electricity and run for years without problems…. No ship operators that we spoke to feels comfortable with microbes living in their bilge or the potential risks associated.  According to Canadian microbiologists, microbes always mutate into several different strains.


Do you use dangerous microbes, chemicals, or other hazardous materials?  Absolutely not! We use the laws of physics and our unique patent is the only patent in the world capable of achieving this level of separation without filters. Talk about inexpensive.


Does the Crystal Sea Separator need constant monitoring? No. Our system is completely fully automated and has virtually no internal moving parts, low maintenance, and is trouble free.


Will your system need to slow down in very concentrated bilges? Will costs go up?  The Coast Guard tested our separators with 100% influent of oil and our effluent contained less than 5ppm contamination. So, no, our system is not variable speed no matter how much oil needs to be separated. There is no need for an operator to be adjusting speeds depending on oil levels in the bilge. Our separators are so effective that even under extreme circumstances the first 5 stages of our process reduce the impurities to 2 ppm without the sixth filtering stage. 



Does the MU-30 or MU-40 require the Oily water to be heated? I ask because I have noticed that the Alfa Laval and Westfalia centrifugal units require the water to be heated for the units to operate. I noticed your units have gravitational and coalescing stages as well as a centrifugal state? Crystal separator is operating at any temperature and it has been tested at temperatures as low as 40 F. The fourth stage does not have a centrifuge such as that of Alfa Laval or Westfalia. There are no moving parts and no maintenance whatsoever is required.  Alfa Laval and Westfalia cannot operate at ambient temperature and need the water to be heated at elevated temperature, around 190 F. This is one of their major disadvantages. Heating the bilge water at this temperature requires a great amount of energy. For example, in the case of a 5 m3/h, in order to increase the temperature from 60F to 194 (15 C to 90C) an electric heater with a rated power of 435 KW would be needed, without taking into account heat losses or the power of the centrifuge driving motor, gear pump, etc. For comparison, the electric power required by Crystal MU 30 of the same capacity is less than 1.5 KW. Therefore, operating costs of the Alfa Laval/Westfalia are at least 290 times higher. If a boiler was used, the power required by Alfa Laval/Westfalia would be 44 HP or 1484365 BTU per hour.



Is there Bilgewater legislations? Current MARPOL legislation stipulates that separated bilge water containing 15 ppm or below oil in water can be discharged into international waters. Some national, regional and local authorities, especially those governing sensitive waters, have more stringent regulations. In the United States and in the Baltic and North Seas, for instance, discharge of separated bilge water is only permitted at least 12 nautical miles from shore.



Can the control panel be separated from the unit if it needs to be relocated because of space? Yes, the control panel can be separated and placed away from the separator in any convenient space.
I’m working on replacing the oily water separators for the 378 class ships and space is at a premium. Also there have been some problems with the gravity coalescers in the past due to the rocking of the ships, but I was interested in how yours has both the gravity coalescers as well as the centrifugal stage.   Crystal separator is the most compact on the market and the only one that can be placed against a wall or in a corner since access to it is needed only from the front. The separator has been operated in all kinds of sea conditions/weather during the trial period and its performance has not been affected in any way whatsoever by the movement of the ship. The coalescing stages and the centrifugal stage are completely impervious to the rocking of the ship.
Does the oily water have to settle for any amount of time for the unit to be effective? No, the separator does not need to settle for any amount of time and can be operated at any time instantly.  Alfa Laval and Westfalia separator need a gravity tank where the mixture needs to settle because the centrifuges cannot handle high concentrations of oil. As a result, a bulky tank is needed which significantly increases the space requirements of the unit and also installation costs.
It sounds like the major benefit if your system is that if we use your OWS, the oil discharge can be burned in the boiler or discharged as slops?  Is this the only OWS on the market that allows the oil to be burned in the boiler?  And what’s alternative to being discharged as slops? Yes our oil discharge can be burned. It depends on the type of burner they use. If it is cup type nozzle the oil can be burned in the boiler as fuel.


Have your units been installed on any other ships? Have they been installed on military ships? Crystal technology is the newest and most advanced on the market. Two, of 0.5 m3/h and 5 m3/h respectively have been installed on Vela Lines vessels so far. Marine separator are modified, more advanced  models of the separators for industrial use which have been in operation since 1997. Currently the Australian Navy is interested in buying Crystal as its Model, MU2 of 0.25 m3/h capacity is the most compact worldwide, it can be located against a wall and even in a corner and the only one that can be placed on their submarines.