Patent ID: 7954478

Claim:
A method for operating an internal-combustion engine, said method comprising the steps of (a) providing an internal-combustion engine that uses recycled combustion gas instead of air, said engine including: (1) at least one cylinder, (2) a cylinder chamber within said at least one cylinder, and (3) a piston that can reciprocate in said at least one cylinder, whereby volume of said cylinder chamber can be varied, (b) providing a gas-cooling means for receiving, cooling and discharge of said engine combustion gas, (c) providing a gas-intake means for selectively connecting said cylinder chamber to said gas-cooling means and for receiving cooled combustion gas from said gas-cooling means into said cylinder chamber in timed relation to said engine operation, (d) providing a gas-exhaust means for selectively connecting said cylinder chamber to said gas-cooling means and for discharging hot combustion gas from said cylinder chamber into said gas-cooling means in timed relation to said engine operation, (e) providing an oxygen-delivery means for adding oxygen to said combustion gas, (f) providing a fuel-delivery means for adding fuel to said combustion gas, (g) providing a pressure-control means for controlling the pressure of said recycled combustion gas and for discharging excess combustion gas through an exhaust pipe into outside atmosphere, (h) providing a control means for controlling the operation of said internal-combustion engine in response to operator's demands and in accordance with a control program incorporated in said control means, (i) operating said engine in a gas-recycling mode by repeatedly performing an engine cycle that includes the steps of: (1) receiving said cooled combustion gas from said gas-cooling means into said cylinder chamber, (2) adding oxygen and fuel to said cooled combustion gas, whereby a combustible mixture forms, (3) using said combustible mixture to perform an internal-combustion cycle in said cylinder chamber, whereby said hot combustion gas forms, (4) transferring said hot combustion gas from said cylinder chamber into said gas-cooling means, and (5) discharging excess combustion gas through said pressure-control means into outside atmosphere, and (6) cooling said hot combustion gas in said gas-cooling means, whereby said hot combustion gas turns into said cooled combustion gas, and (j) using said control means for control of operation of said internal-combustion engine, whereby said engine operates without receiving air from outside atmosphere, whereby said combustible mixture contains no nitrogen, whereby no nitrogen oxides are produced in said engine, and whereby harmful exhaust emissions are recycled back into said engine and burned there.