Asphalt production plants need a constant supply of thermal energy for their production. Given the high temperature required for the process, thermal oil heater with natural gas burner is the ideal solution, as the working temperatures of the fluid are around 270ºC.
However, due to the characteristics of the fluid, thermal oil heaters only enjoy efficiency of around 86%.
As part of its commitment to energy efficiency, Repsol chose Sugimat to increase the performance of the current boilers supplied by Sugimat in 1989 and 1990. In this way, it was possible to reduce the amount of CO2 emitted and save on fuel.
In this sense, Sugimat modernized the installation by adapting the heaters to burn natural gas with preheated air. The supply consisted of replacing the old diesel burners with new dissociated natural gas burners, together with economizers to preheat the combustion air.
The increase in efficiency by means of a gas-air economizer consists of taking advantage of the residual heat contained in the combustion gases, making them pass through a tube economizer through which air circulates, which will be injected into the burner as combustion air.
In this way, preheated air can be introduced up to 200ºC, achieving an increase in the performance of the installation of up to 7 percentage points. This implies an important reduction of the CO2 emitted to the atmosphere, as well as an important economic saving.
This investment could be amortized in a period of less than 3 years of operation.