STUDY IN POWER PLANTS
Date : November 2001 Updated November 2015
1- EXPERIMENTAL DATA TO BE USED IN THE CALCULATION
The following data to be used in the calculation have been gathered from the experience accumulated by rb bertomeu S.L. in power plants with Diesel engines running on heavy fuel oil and it is fully guaranteed that they are obtainable by using the additive “rb bertomeu” beco F1/ASF and following the specified dosing and procedures, regardless of the type of Diesel engine considered.
When calculating the profitability achievable with the adoption of the additive “rb bertomeu” beco F1/ASF, according to the particular power plant one should apply the increases or reductions specified to the historical data recorded when the engines were in operation without the additive treatment.
1-1 Increase in normal TBO for maintenance of exhaust valves : + 50 % min.
1-2 Increase in the normal operational life of valves (due to corrosion): + 100 % min.
1-3 Reduction in valve blowouts in normal : 80 % average
1-4 Increase in normal TBO for cleaning turbos : + 50 % min.
1-5 Increase in the normal operational life of turbos (due to corrosion): + 100 % min.
1-6 Reduction in fuel consumption per kWhe , due to better
combustion and fuel sludge reduction : 1.5 % average
1-7 Reduction in fuel consumption per kWhe , due to
lower erosion of injection equipment : 0.9 % average
1-8 Reduction in fuel oil sludge to be treated or handled : 70 % average
1-9 Reduction in hours of stoppage for maintenance : 30 % min.
1-10 Increase of annual Service Factor, as a consequence of
less stopages due to breackdowns and programmed maintenance : To be calculed for each engine or plant.
2- BASES OF THE EXPERIMENTAL DATA
2-1 REDUCTION IN CORROSION ON EXHAUST VALVES
One of the reasons for the high profitability of the use of the additive “rb bertomeu” beco F1/ASF is undoubtedly the increase in the operational life of the exhaust valves of the engines by neutralising the corrosion. This provides great savings on the replacement of valves, in the labour costs of valve overhauls and in stoppages caused by valve blowouts, as well as an increase in the time between overhauls for valves (TBO), in relation to normal maintenance schedules.
Regarding the increase in TBO for exhaust valves , see our report “Tests for doubling TBO in engines of EWCAR”, dated May-02, which was realized jointly with the owner of the power plant and the engine manufacturer. In these trials was demonstrated the viability of doubling the normal TBO used for the exhaust valves in Diesel engines. Since then, until now, end of 2015, the company has not stopped using the additive as can be seen in the letters of reference, having increased the valves TBO up to 7,200 hours. In this link, you can find more letters of reference that support all what is being said in this report.
The fact that the anti-corrosion effects are able to be extrapolated for any type of engine is widely accepted on the grounds of the following key points:
2-1-1 When fuel oil is burned in a Diesel engine corrosion takes place, mainly on the exhaust valves, due to chemical attack on the alloy by compounds formed from impurities contained in the fuel oil, principally Vanadium, Sodium and Sulphur, while other metallic impurities are involved to a lesser extent. These compounds, at the high temperatures to which the exhaust valves are subjected (in excess of 800º C during combustion and 350-400º C in the exhaust gases) are inevitably corrosive. Some Sodium Vanadates are especially corrosive, being in a liquid state at temperatures as low as 340-350ºC.
2-1-2 Chemical corrosion is aggravated by the thermal fatigue to which a valve is subjected in the case of inappropriate operation, design or assembly. This can cause changes in the structure of the metal, making it more fragile, and liable to chemical attack from the corrosive compounds detailed above.
2-1-3 In order to prevent an excessively fast rate of corrosion on valves, state-of-the-art alloys are employed in the design of valves, which have been adopted by the majority of manufacturers as a fundamental principle to reduce the problem of corrosion. In spite of this, the problem has not been completely resolved and new designs and materials are continually being developed.
2-1-4 In addition to the type of material or alloy used in the construction of the valves, the rate of corrosion depends on the overall engine design and on the desing of valves themselves. In certain designs, several manufacturers resort to installing exhaust valves with greatly thickened material in the area of the seats, and thereby, with corrosion occurring at a certain rate, the life of the valves is prolonged.
2-1-5 The application of an appropriate anti-corrosion treatment, as it is the additive “rb bertomeu”, reduces chemical corrosion on the valves to a minimum, for any given engine design, type of valve and component material.
Assuming the engine is well designed, its valves are made of suitable material, and its mechanical assembly is faultless and that the engine is run in suitable conditions, the operational life of the valves depends on:
- Manufacturing defects of the exhaust valves, which are a main factor in the rate of valve blowouts.
- The onset, in the long term, of thermal and/or mechanical fatigue.
- Chemical corrosion due to impurities in the fuel oil, which is a factor in the general corrosion of the seats and the rate of blowouts due to thermal stress and small defects acquired.
The treatment of the fuel oil with “rb bertomeu” beco F1/ASF does not prevent the blowout or failure of an exhaust valve with manufacturing defects nor the various types of long-term fatigue. However, it does neutralise the chemical corrosion that reduces its operational life.
2-2 REDUCTION IN CORROSION AND INCRUSTED RESIDUES ON TURBOS
The reduction in the level of corrosion and incrusted residues achieved, both on exhaust valves and Turbos and other parts of the exhaust gas circuit (fundamentally boiler heat exchangers) , is thanks to the additive raising the melting point of these residues.
With this effect, the corrosive salts formed during combustion of fuel oil are no longer in a liquid state or partially melted at temperatures as low as 330-350 ºC , as their melting points are increased to temperatures in excess of 1,000 ºC. Therefore, as the salts are only present in a solid state at the temperature of the gases in turbos and the rest of the exhaust gas circuit (320-400º C), their corrosiveness as well as their adherence to metallic surfaces is significantly reduced, and they are carried along with the gases. This prevents the usual problems that arise when no treatment is used.
It can easily be appreciated and demonstrated by experimental data that the rate of incrustation of the residues with a high melting point on the metallic parts of the circuit is much less than that of the residues with a low melting point. Given that the formation of residues during the combustion of fuel oil is inevitable, the modifying effect of the additive “rb bertomeu” derives from a significant reduction in incrusted residues and the consequent reduction in the need for their removal.
In the case of Turbos, there is an increase in the time interval allowed between stoppages for cleaning of between 50% and 100% on the normal interval, depending on the type of turbo and quality of the fuel oil.
Although the rate of corrosion is much less than on the exhaust valves, the action of the additive “rb bertomeu” achieves a reduction in corrosion, such that it doubles the time taken for corrosion to appear on any of the components of the turbo (rotor, housing, etc.). There is experimental verification for the estimation of the onset of problems caused by corrosion on Turbos (when some of the component parts begin to need replacing), with and without the additive “rb bertomeu”, as follows:
a) WITHOUT using “rb bertomeu” beco F1/ASF : From 10,000 to 16,000 Hours
b) WITH the additive “rb bertomeu” beco F1/ASF : Over 40,000 Hours
2-3 REDUCTION IN FUEL CONSUMPTION
The second most important reason for the high profitability of the use of the additive “rb bertomeu” is undoubtedly the reduction in fuel consumption per unit of energy produced by the engine. In the case of fuel oil, this reduction in consumption, (as has been amply checked) is brought about by the action of the additive prior to combustion, from the storage tanks to the point of injection.
The document Dossier rb, Section B-3, details the action of the additive "rb bertomeu" on the fuel oil, promoting the disintegration and dispersion of solids during storage and improved atomisation of the fuel at the point of injection into the combustion chamber of the engine. See the document RB-3. Reducción del consumo de fuel oil en plantas de generación eléctrica con motores diesel, being a large study over the fuel consumption that took place in a power plant, where the savings are demonstrated. Likewise, in the forementioned Dossier rb, you can read several letters of reference from power plants with Diesel engines that certify the real decrease in fuel oil consumption due to less erosion on the injection nozzles (Section F-2).
Essentially, the total saving in consumption results from a combination of three main factors, uniquely provided by the action of the additive “rb bertomeu”:
2-3-1 REDUCED FUEL OIL SLUDGE
The action of the additive “rb bertomeu” in the storage tanks, disintegrating the existing sludge and emulsifying it in the fuel, while preventing sludge re-forming over time, reduces the quantity of organic sludge that is decanted in the tanks and removed by the fuel purifiers. This organic sludge which is not removed is then actually used as fuel, whereas without the additive it is eliminated and fuel consumption is increased.
At the same time, any costs of removal or treatment of sludge in plants (performed internally or by authorised contractors) are reduced in the same proportion as the percentage of reduction of sludge obtained from treatment with “rb bertomeu”.
2-3-2 IMPROVED ATOMISATION OF THE HEAVY FUEL OIL
The efficient surfactants contained in the additive work to achieve improved atomisation of the fuel oil in the combustion chamber with the same temperature, pressure and atomising components. This improved atomisation provides more thorough combustion in the combustion chamber by optimising the fuel-air mixture, thereby achieving greater conversion of the calorific value of the fuel and, consequently, reduced consumption per unit of energy produced by combustion in the engine’s combustion chamber.
In addition to checking consumption, the evidence of improved combustion is easily demonstrated by the following:
- The absence of black smoke composed of unburned particles
- Reduction in CO in exhaust gases
- Reduction in the opacity of exhaust gases (reduction by approximately 2 points on the Bacharach scale)
2-3-3 MAINTAINING THE QUALITY OF ATOMISATION
It is widely acknowledged by engine manufacturers that fuel consumption increases as the injection components suffer ageing and wear, eventually using up to 3% more fuel towards the end of the operational life of the components in comparison with newly-installed ones.
Sufficiently extensive checking will demonstrate that the additive “rb bertomeu” is effective in neutralising the effects of wear on the injection components and prolonging their operational life. This delays the gradual onset of the increase in consumption, something inevitable without the use of the additive “rb bertomeu”, providing direct saving which often goes unnoticed or is not calculated because it is assumed that there would not be a palpable increase in fuel consumption without the use of the additive beco F1/ASF.
some tests carried out in power plants with Diesel engines
runnig on heavy fuel oil, reduction of fuel consumption arounf
0.9 – 1.2 % , due to above explained concept, have been
IMPORTANT NOTE: In the economic calculations that we do for our customers, the lowest value detected is applied throughout, 1.5% (due to better combustion and less fuel sludge) and 0.9% (due to lower erosion of injection equipment), as a conservative average value for the purposes of calculating profitability for the customer.
The sum of these three factors in the reduction in consumption result in an overall saving of between 1.5% and a 3.5%, depending on the type of fuel oil, the type of engine and its maintenance and operation.
We will be very pleased to make a personalized economical study accordingly to the charasteristics of your plant. Please contact us at email@example.com
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