Even with the most efficient engines on the market today a substantial portion of the energy content of fuel is lost via exhaust gases and engine cooling. What is proposed herein is a method of minimizing these losses by using the water in water emulsified fuel to absorb the majority the heat. Combined cycle is a well-established technology in large scale stationary power plants with efficiency improvements of up to 70%. However efforts to use combined cycle in non-stationary/vehicular applications have not been successful due to the bulkiness of the required equipment not to mention that the exhaust gas temperatures of nonstationary engins which are relatively small is not sufficient effectively vaporize the water in water emulsified fuels and usually results in engine power loss.
As in my patent (US9022006), all these problems are solved by using Process Intensification (a relatively new branch in Chemical process engineering) to safely apply Oxy-fuel combustion using a wall integrated injector (Fig 1) to raise combustion temperatures which are immediately absorbed by the water in the fuel thereby exploiting the high heat capacity of water to absorb heat and taking advantage of the high expansion ratio of water contribute to the conversion of heat energy to motive power. This contribution serves not only to increase power but also to lower the CO2 emissions per unit distance.
One advantage of Oxy-fuel combustion is that Nox emissions are minimized by using higher than normal exhaust gases recirculation. And as demonstrated in the above mentioned patent, if so desired, it’s possible to run at 100% EGR when all of the Oxygen required is supplied in a process intensified manner.
Fig 1A shows Wall integrated injector 1 with fuel passage 4 and oxidant passage 5 along with multiple orifices 6 (only three shown) evenly spaced around the combustion chamber (not shown). This multi-fluid injector is positioned at the very top of the combustion chamber so that the oxidant fuel mixture from orifices 6 is directed into the squash area of the chamber.
Fig 1B is a cross section of one of the micro injectors inside wall integrated injector 1 showing fluid passage 4 and 5. The micro injector is shown in the open state and so allowing fuel and oxidant passages to be connected to Passage 3 is where the oxidant and fuel mix prior to being injected into the squash area via orifice 6.
The wall integrated injection of the above mentioned patent allows for safe oxy-fuel combustion inside the combustion chambers, shrinking all of the required equipment without damaging chamber walls making it possible to run combined cycle using the same engine/combustion chambers. These are some of the advantages:
- Cutting CO2 emission in IC engines by at least 50%
- Increasing efficiency of the IC engines with no penalty to efficiency and power
- Reducing and or completely eliminating Nox emissions. This is possible when all the required oxygen is supplied in a process intensified manner and while running at 100% EGR.