A method of aerating wastewater comprising: - introducing the wastewater into a primary pressurizable aeration tank (PPAT), wherein the level of wastewater in said primary pressurizable aeration tank (PPAT) is controlled to maintain a pressurized air region at the upper end thereof; - pumping wastewater from said primary pressurizable aeration tank (PPAT) into a secondary pressurizable aeration chamber (SPAC); - aerating the wastewater in the secondary pressurizable aeration chamber (SPAC), wherein the wastewater in the secondary pressurizable aeration chamber (SPAC) is aerated by: introducing compressed air into said secondary pressurizable aeration chamber (SPAC) to produce an atmosphere of compressed air therein; pumping wastewater into said atmosphere of compressed air in said secondary pressurizable aeration chamber (SPAC); and atomizing the wastewater pumped into said atmosphere of compressed air in said secondary pressurizable aeration chamber (SPAC), wherein the wastewater is atomized by directing a jet of the wastewater against a splatter plate; and - recirculating aerated wastewater from said secondary pressurizable aeration chamber (SPAC) back to said primary pressurizable aeration tank (PPAT), wherein the wastewater circulated from said secondary pressurizable aeration chamber (SPAC) back to said primary pressurizable aeration tank (PPAT) is atomized in said pressurized air region of said primary pressurizable aeration tank (PPAT) to further enhance the aeration thereof. - introducing the wastewater into a primary pressurizable aeration tank (PPAT), wherein the level of wastewater in said primary pressurizable aeration tank (PPAT) is controlled to maintain a pressurized air region at the upper end thereof; - pumping wastewater from said primary pressurizable aeration tank (PPAT) into a secondary pressurizable aeration chamber (SPAC); - aerating the wastewater in the secondary pressurizable aeration chamber (SPAC), wherein the wastewater in the secondary pressurizable aeration chamber (SPAC) is aerated by: introducing compressed air into said secondary pressurizable aeration chamber (SPAC) to produce an atmosphere of compressed air therein; pumping wastewater into said atmosphere of compressed air in said secondary pressurizable aeration chamber (SPAC); and atomizing the wastewater pumped into said atmosphere of compressed air in said secondary pressurizable aeration chamber (SPAC), wherein the wastewater is atomized by directing a jet of the wastewater against a splatter plate; and introducing compressed air into said secondary pressurizable aeration chamber (SPAC) to produce an atmosphere of compressed air therein; pumping wastewater into said atmosphere of compressed air in said secondary pressurizable aeration chamber (SPAC); and atomizing the wastewater pumped into said atmosphere of compressed air in said secondary pressurizable aeration chamber (SPAC), wherein the wastewater is atomized by directing a jet of the wastewater against a splatter plate; and - recirculating aerated wastewater from said secondary pressurizable aeration chamber (SPAC) back to said primary pressurizable aeration tank (PPAT), wherein the wastewater circulated from said secondary pressurizable aeration chamber (SPAC) back to said primary pressurizable aeration tank (PPAT) is atomized in said pressurized air region of said primary pressurizable aeration tank (PPAT) to further enhance the aeration thereof.