rb bertomeu, S.L.

Pol. Ind. Fondo de Llitera, Par. 82-83

E-22520 Fraga, Huesca (Spain)

Tel.: +34 974 47 48 04

+34 630 43 08 43






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MARPOL waste consists of heavy fuel oil sludge, oil sludge, used engine lubricating oil, spillages of fuel oil and Diesel fuel, water used to clean filtration systems, waste from cleaning tanks and drains, the contents of the bilge tank and sludge tank, etc., which are produced in ships during sea crossings. Upon reaching port, this waste is consigned to authorised waste management and treatment companies for its recovery.

These authorised companies also manage and treat other hydrocarbons produced by other industrial activities, such as all types of lubrication oil, contaminated fuel oil and Diesel fuel, petroleum spirits and their derivatives, and other types of flammable products that are mixed with MARPOL waste.

Some of the waste is characterised by containing over 50% water, which must be separated by several processes of decantation and centrifugation, so that the MARPOL waste may later be used as a fuel (possibly mixed with fresh heavy fuel oil), in Diesel engines or in boilers, furnaces, etc.

One of the main problems created by its use in Diesel engines or in boilers is the high presence solid waste in the combustion gases produced. These waste products largely arise from fuel oil sludge and oil sludge from engines. Thus, MARPOL fuel usually contains, in comparison with heavy fuel oil, high quantities of Calcium (1,000 2,000 ppm, as opposed to 5-10 ppm in heavy fuel oil from a refinery), Iron (100 - 250 ppm, as opposed to max. 10 ppm in fuel oil), Ash (0.4 0.7%, as opposed to max 0.1%. in heavy fuel oil), so that these compounds produce incrusted residues to abnormally high levels in the circuit of gases from combustion (turbo-compressors, heat exchangers, economisers, etc.) as well as in the combustion chambers of engine cylinders. In practice, this situation causes numerous stoppages for cleaning, a low Service Factor of the installations and increased maintenance costs.

Tests of additive treatments have been performed over several months (more than one year) with additives from "rb bertomeu" in an installation with Diesel engines running on heavy Fuel oil derived from recovered MARPOL waste, in an attempt to reduce, on the one hand, the exceptionally high level of incrusted residues produced, especially in the gas sections of turbo-compressors and combustion chambers in cylinders, which entail continual cleaning and overhauls; and on the other hand, to reduce the frequent and arduous cleaning operations on fuel separators and fuel filters. The additive employed was of the type "rb bertomeu" beco F1/ASF and the results obtained, as reported to us by PORT ECOREL, the Plant consuming MARPOL , after several months in operation, are described below.

-Reduction in the frequency of cleaning turbo-compressors: The frequency of cleaning the turbo has been reduced, using the water injection method, from 5 times per week to 3 times per week (Reduction of 40%) and in addition the cleaning operation is more effective because the incrusted residue is more easily removed. Thus, the time spent on cleaning has also been reduced.

-Reduction in the time required to clean fuel Separators: There has been a most noticeable improvement in the frequency and the time spent on the arduous task of cleaning the fuel oil separators. The frequency of cleaning had reached an average of once every ten days, whereas now it has been reduced to once every thirty days (triple of cleaning TBO). The time spent on cleaning the separator has been cut down, and the cleaning operation is easier to carry out, requiring much less effort. This has led to a significant reduction in maintenance costs, both for replacement components for the separator and costs incurred for labour.

-Reduction in the labour required for cylinder head maintenance: Less time is spent on reconditioning the injectors, especially in cleaning incrustations off the injectors and the sleeve to which they adhere. Similarly, it is now easier to clean the cylinder head.

-Prolonged life for injection nozzles: There is clear evidence of a significantly prolonged operational life for injection nozzles, which leads to a reduction in maintenance costs (yet to be quantified).

-Increased production of electrical energy and a reduction in costs: All the above factors mean that annual energy production increases, as fewer maintenance stoppages are required, and maintenance costs are reduced, thereby increasing the profitability of the cogeneration plant.

Given that MARPOL waste also contains Vanadium and Sodium, there is also a reduction in corrosion at high temperatures caused by sodium vanadates, in line with the reduction in corrosion obtained when using fuel oil treated with the same additive. In this case, as the tests are short-term, and intended merely to verify differences in the accumulation of residues, measurements were not made of the reduction in corrosion, which will undoubtedly become apparent in the medium and long term.

For further information on this subject, please consult the following documents from rb bertomeu (click on the chosen title):



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