DESMI Proven Technology 1

DESMI Proven Technology 2

DESMI Proven Technology 3

DESMI Proven Technology 4

DESMI Proven Technology 5


DESMI Ocean Guard RayClean
Ballast Water Treatment System

Proven effective in all water salinities with UV-T (UV-Transmission) as low as 0.33 which sets the industry benchmark.

- lowest energy consumption in class

RayCleanTM Ballast Water Treatment System is the leading system in the marine industry with unrivalled treatment performance and lowest energy consumption in class.

RayCleanTM is IMO and DNV type approved and has earned the Alternate Management System (AMS) acceptance by the US Coast Guard (USCG). The AMS acceptance covers all salinities ranging from freshwater to marine water, something that only eight out of 52 issued AMS acceptances have achieved to date. RayCleanTM has been proven capable of dealing with extremely dirty and unclear water – a wide UV transmission range that no other UV system on the market today is approved for.

RayCleanTM has been tested in accordance with both the IMO and USCG requirements and with DNV GL as Independent Lab appointed by USCG and all testing facilities have been approved by USCG.



The RayCleanTM system

Easy and fully automatic operation

RayCleanTM is a fully automatic process based on a PLC platform, which controls the valves, pumps, UV sensor, flow meters, pressure- and temperature sensors.

The operation of the system is made as simple as possible. The operator only has to start and stop the ballast and de-ballast operation and the remaining part of the operation is then fully automatic.
RayCleanTM can be started or stopped from the colour graphic Touch Screen on the Master Control Panel which can be integrated in an existing control system on board the vessel.

RayCleanTM is automatically optimizing the power consumption via dimming of the lamps and regulation of the flow in accordance with the characteristics of the water. During ballast and de-ballast operations the control system is logging the operation data and time-stamp the date before it is saved into a log file.



RayCleanTM has a self-cleaning filter in order to remove the vast majority of organisms larger than 50 micron.
During de-ballast the filter is used to ensure that organisms which are small or soft enough to pass the filter on uptake, and which have grown large enough to be stopped by the filter mesh at discharge, will be treated and rendered inactive.

The RayCleanTM filter system has a unique and patent pending way of recirculating the filter backflush stream on ballast water discharge.


The UV treatment takes place in units with a flow capacity of 300 m3/h. Each UV unit is equipped with 60 highly efficient low-pressure UV lamps. These lamps are roughly twice as energy efficient as the widely used medium pressure UV lamps, and as they work at much lower temperature they have superior lifetime and no issues with regard to fouling.

Constant online monitoring of the UV intensity inside each unit is used to dim the UV lamps in very clear water (high UV-Transmission) in order to save energy, and to reduce the flow through the unit in extremely unclear water (low UV-Transmission). This ensures a carefully dosed UV treatment at all times resulting in IMO and USCG compliance even in extremely challenging water conditions. All lamp dimming and flow control are fully automatic.


RayCleanTM consists of two types of control panels, a Master Control Panel and a number of UV Control Panels, one for each UV unit.
RayCleanTM is controlled by the PLC located in the Master Control Panel. The UV Control Panels are connected to the Master Control Panel via a Profinet Ring bus. The Master Control Panel has a 15” colour graphic touch screen (also called HMI). This is used for local control of the system, but as an option one or more HMI’s can be offered and integrated into the solution. RayClean can interface with the vessel’s Integrated Ship Automation System and/or Power Management System. This is can be made either as hardwired signals via a multicore cable and/or as MODBUS RTU communication.

Click here to download brochure







Types of system deliveries

Component delivery

Component Delivery

Skid mounted solution

Skid mounted Solution

Container solution

RayClean Container Solution

RayClean - lowest energy consumption in class

The low power consumption is achieved by use of highly energy efficient low-pressure UV lamps combined with lamp dimming in clear water (high UV-T) and flow reduction in very challenging and unclear water (low UV-T).

By monitoring the UV intensity inside each unit the lamps can be dimmed when the intensity is higher than the critical level, and the flow can be reduced when the intensity is lower than the critical level. This results in a constant applied UV dose independently of the UV-T of the water to be treated.

Under normal conditions where the UV-T is higher than 0,55 the flowrate per unit is 300 m3/h and the energy consumption of the entire system is around 8 kWh/100 m3 when lamps are not dimmed, and as low as 5 kWh/100 m3 when the lamps are dimmed as much as possible.

Capacity [m3/h] System Power
Consumption* Max. [kW]
System Power
Consumption* Min. [kW]
Weight [kg] Foot Print** [m2]
100 21 11 1425 5
200 21 11 1425 5
300 21 11 1675 5
400 42 22 2525 6
500 42 22 2975 6
600 42 22 2975 6
700 63 33 3825 8,5
800 63 33 4075 8,5
900 63 33 4075 8,5
1000 84 44 4925 10,5
1100 84 44 4925 10,5
1200 84 44 5375 10,5
1300 105 55 6175 11,5
1400 105 55 6175 11,5
1500 105 55 6175 11,5
1600 126 66 7525 12,5
1700 126 66 7525 12,5
1800 126 66 7525 12,5
1900 147 77 8325 14,5
2000 147 77 8875 14,5
2100 147 77 8325 14,5
2200 168 88 9725 16
2300 168 88 9725 16
2400 168 88 9725 16
2500 189 99 11075 17,5
2600 189 99 11075 17,5
2700 189 99 11075 17,5
2800 210 110 11975 19
2900 210 110 11975 19
3000 210 110 11975 19


Long lifetime on UV-lamps

Self-cleaning UV-unit

The RayCleanTM UV-lamps have a very long lifetime of approx. 12,000 hours.

This keeps your operational expenses down.

The UV-unit is a mechanical self-cleaning
unit without any use of chemicals.

This saves you a lot of maintenance time and no chemicals are needed on board for UV-unit cleaning.


To the top

Visit DESMI at OMC 2017

DESMI will be present at the OMC Offshore Mediterranean Conference & Exhibtion held in Ravenna, Italy 29-31 March 2017. Locate us at booth C20 in Hall 2..

I’m interested. Tell me more

Come visit us at the Atlantic Fair 2017

The Atlantic Fair is taking place 9th-11th May in Klasvik, Faroe Islands.

I’m interested. Tell me more

Come visit us at Maritime Industry 2017

The Maritime Industry is taking place 9th-11th May in Gorienchem, The Netherlands.

I’m interested. Tell me more

Visit DESMI at All Energy 2017

The UK's premier event for renewable energy and sustainable technologies is taking place in Glasgow, UK, 10th-11th May.

I’m interested. Tell me more

Come visit us at IOSC 2017

The International Oil Spill Conference provides a vital forum for professionals from the international response community,
private sector, government and non-governmental organizations. It is taking place from 15-18th of May in Long Beach, CA.

I’m interested. Tell me more

Visit DESMI at REITZE TEC 2017

Technique, Trends & Innovation is the keywords at this years REITZE TEC exherbition in Bremen.
Join us the 17th and 18th of May 2017.

I’m interested. Tell me more

Visit DESMI at BARI-SHIP 2017

Join us the 25th to 27th of May 2017 at the Imabari Maritime Fair in Japan.

I’m interested. Tell me more

Come visit us at Nor-Shipping 2017

For more than 50 years Nor-Shipping has been attracting key maritime industry players from around the world. 
It is taking place May 30 - June 2 2017 in Oslo, Norway.

I’m interested. Tell me more

Visit DESMI Future Surface Fleet 2017

DESMI will be present at the Future Surface Fleet Conference in Portsmouth, Englad 6-8 June 2017.

I’m interested. Tell me more

Visit DESMI at AquaNor 2017

Since 1979, Aqua Nor has been an important international meeting place for the aquaculture industry.
In 2017 it is taking place the 15-18 August in Trondheim, Norway.

I’m interested. Tell me more

Come visit us at Donsö Shipping Meet 2017

Swedens biggest shipping event is taking place 5-6 September 2017 in Donsö, Sweden.

I’m interested. Tell me more

Come visit us at BaltExpo 2017

The 19th International Exhibition and Conferences BaltExpo will be held 11-13 September 2017 in Gdánsk, Poland

Come visit us at NEVA 2017

Neva is an international shipping, shipbuilding, ports and offshore energy exhibition and the largest maritime forum in Russia. 
It is taking place  19. - 22. September 2017 in Saint Petersburg, Russia.

I’m interested. Tell me more

Visit DESMI at INMEX SMM India 2017

South Asia's largest maritime exhibition and conference is taking place in Mumbai, India the 3rd-5th of October 2017.

I’m interested. Tell me more

Come visit us at DanFish 2017

One of the world's largest trade fairs for equipment for the fishing industry is taking place in Aalborg, Denmark the 11th-13th of October.

I’m interested. Tell me more

Come visit us at Kormarine 2017

The 39th edition of Kormarine is taking place 24-27 of October in Busan, Korea.
Visit DESMI as we exhibit our marine pumping solutions

I’m interested. Tell me more

Visit DESMI at Europort 2017

The international maritime meeting place for innovative technology and complex shipbuilding is taking place
in Rotterdam, The Netherlands, 7th-10th November.

I’m interested. Tell me more

Come visit us at Marintec 2017

The largest maritime event in the Asia Pacific is taking place from the 5-8th of December in China.

I’m interested. Tell me more