Used engine oil is a main source of oil contamination of waterways and can result in pollution of drinking water sources. Insoluble, persistent, slowly dergradable, it can contain toxic chemicals and heavy metals. Animals and birds from the polluted oil soil can be stuck. The present study aims to contribute to solving the environmental problem and energy saving purpose by recovering waste from the recycling of used oil to improve the firing of clay bricks. The waste from recycling used oil is collected and mixed with wood charcoal. This mixture is used as fuel in the artisanal kiln to fire the bricks. The temperature rises in the kiln, the cooling time and the quality of baked Clay Bricks are analyzed. The maximum temperature observed inside the kiln is 900°C in 36 hours of kiln operation when wood charcoal is used as fuel with a firing time of five (5) days and 1020°C in 80 hours when wood charcoal and “Chinese coal” (waste from the recycling of used oil) are used as fuel with a firing time of ten (10) days. This explains the longer cooling time than with wood charcoal alone as fuel. The firing of the bricks is perfect with both fuels, whereas, with wood charcoal alone as fuel, 15% of the bricks are unbaked. The bricks also have a very clean appearance. They have an average shrinkage of 1%, which is lower than the normative value of 3%, the average compressive strength is 16.5MPa which is higher than the normative value of 12.5MPa, and the water absorption is 40% which is lower than the normative value of 60%. This combination of fuels reduces the use of wood charcoal, which in turn reduces deforestation and prevents air pollution and soil degradation through the dumping of waste oil in the environment.

In the current energy context, geothermal systems are highly developed in the building field. Among these interesting systems on the energy plan, one finds in particular the earth-to-air heat  exchanger commonly called ‘Canadian or Provençal well’. It consists of tubes buried in which the ambient air is pushed in order to be refreshed in contact with the ground whose temperature is quasi-constant throughout the year. In this work, a study of the performance of an earth-to-air heat exchanger was undertaken by means of numerical modeling of heat exchange by forced convection in a buried tube. The transfer equations in the tube are discretized using the finite volume method in turbulent regime and solved using the Thomas algorithm. For the determination of the ground temperature, the model of the semi-infinite mass subjected to a periodic excitation was adopted. The soil temperature was used as a boundary condition for the buried tube. The results show that the interest of the earth-to-air heat exchanger is major, since it improves throughout the year, the thermal conditions sought. It intervenes in an effective way on the damping of the thermal amplitudes in the building. The variation of the diameter and the length of earth-to-air heat exchanger does not influence notably the distribution of the streamlines and isotherms but affect significantly the values of stream function and temperature inside de tube of the earth-to-air heat exchanger. When diameter of the pipe increases, the outlet temperature increases. The increase of the length of the earth-to-air heat exchanger leads to the isotherms increase as a result of the intensification of heat exchange between the walls and the convective jet. The temperature in the air outlet compartment is lower as the length of the earth-to-air exchanger increases.