Sludge Dispersant

NIPPON YUKA KOGYO >> Sludge Dispersant

Sludge Dispersant

Product name




Yunic 555D

Sludge inhibition and dispersion

Standard dosing rate: 1/8000

Suppress the occurrence of asphaltene sludge due to long-term storage, heating, and mixture of heavy oil.

200L D/M

Yunic 650-II

Sludge dispersion and inhibition
Vanadium ash modification

Standard dosing rate: 1/5000

Suppress the occurrence of asphaltene sludge due to long-term storage, heating, and mixture of heavy oil.
Raise the melting point of vanadium ash and change it to non-adhesion ash.

200L D/M


Precipitation of asphaltene sludge

C heavy oil contains a component called asphaltene. It is not soluble in paraffinic hydrocarbons (an oil that is made of hydrogen saturated bonding to carbon), which is the main component of C heavy oil. In heavy oil, asphaltene is dispersed because it is covered by substance with an intermediate property between asphaltene and paraffinic hydrocarbon. However, when heavy oil is heated or mixed with other type of oil, the covering substance will be removed and asphaltene will be precipitated from heavy oil and settle as sludge.

* Definition of asphaltene: Substance that is soluble in benzene but insoluble in n- heptanes.

* Porphyrin on the right of the above figure is the active central substance of hemoglobin in the blood of animals and chlorophyll in plants. One of the reasons that petroleum is said to be originated from plants and animals is that porphyrin is found in petroleum. M (metal) that is surrounded by 4 Ns (nitrogen) is iron in hemoglobin or magnesium in chlorophyll, and sometimes it is vanadium in heavy oil. Vanadium is a metal with a low melting point and is the reason of combustion failure caused by heavy oil.

Effect of Yunic 555D

Component of Yunic 555D can disperse asphaltene in paraffinic hydrocarbons as an "intermediate substance". Therefore, the addition of Yunic555D can compensate for the "intermediate substance" that is lost due to heating or mixing of other oil. The prevention of asphaltene precipitation and sludge can prevent supply cut of fuel due to strainer obstruction. It can also help to keep the tank clean and improve fuel economy by using up the asphaltene without losing it as sludge.

<Fuel tank that Yunic 555D is being used>

- Ship type

: Ocean-going container ship

- Fuel oil

: C heavy oil (mainly 380cSt)

- Tank capacity

: 900 m3

- Period of use

: 7 years and 8 months

- Tank cleaning

: Yet to be implemented

  • Reduce precipitates such as sludge by helping to disperse asphaltene (Effective use of the entire fuel oil)
  • Improve sprayability by miniaturizing fuel oil
  • Improve ignitability by improving sprayability and improve combustion by shortening of afterburning time

The average fuel efficiency improvement rate is about 3% by these synergistic effects. It has a high effect of improving fuel efficiency by burning the entire fuel efficiently.


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