Liquid cryogen delivery and injection control apparatus

A method for supplying liquid cryogen to a chilling application, the chilling application using the liquid cryogen and for producing an exhaust gas, the method comprising:

• supplying liquid cryogen from a liquid cryogen feed tank to a liquid cryogen conduit in fluid communication between the liquid cryogen feed tank and the chilling application;
• controlling a weight of the liquid cryogen to be delivered to the chilling application through the liquid cryogen conduit by a weight measurement device;
• controlling a speed of delivery of the liquid cryogen to the chilling application by a flow controller;
• measuring a temperature of exhaust gas with a device in operative communication with the flow controller;
• and
• varying the speed of delivery of the liquid cryogen by the flow controller configured to vary the speed of delivery in response to the temperature of the exhaust gas;
• wherein a high-pressure gaseous cryogen tank is in fluid communication with a vessel via a gas conduit, and a pressure control device in communication with the gas conduit between the high-pressure gaseous cryogen tank and the vessel is responsive to the temperature of the exhaust gas, the method further comprising varying a pressure of the liquid cryogen in the vessel with a pressure control device varying a flow of cryogen gas to the vessel.

A delivery apparatus for delivering liquid nitrogen to a bottom injection mixer comprising:

• a low-pressure liquid nitrogen feed tank;
• a liquid nitrogen conduit in fluid communication between the low-pressure liquid nitrogen feed tank and the bottom injection mixer;
• a vessel in fluid communication with the liquid nitrogen conduit and the low-pressure liquid nitrogen feed tank:
• wherein the liquid nitrogen conduit feeds the liquid nitrogen to a plurality of injectors mounted to the bottom injection mixer and in communication with an interior of the bottom injection mixer;
• a weight measurement device for controlling a weight of the liquid nitrogen to be delivered through the liquid nitrogen conduit and the plurality of injectors to the bottom injection mixer, the weight measurement device selected from the group consisting of a weigh scale supporting the vessel, and a load cell supporting the vessel;
• a flow controller for controlling a speed of delivery of the liquid nitrogen to the bottom injection mixer through the injectors;
• wherein the bottom injection mixer uses the liquid nitrogen and produces an exhaust gas;
• a high-pressure gaseous nitrogen tank in fluid communication with the vessel via a gas conduit, and a pressure control device in communication with the gas conduit between the high-pressure gaseous nitrogen tank and the vessel configured to be controlled by an electronic controller responsive to a temperature of the exhaust gas;
• and
• a device for measuring the temperature of the exhaust gas, the device being in operative communication with the flow controller;
• wherein the flow controller is configured to vary the speed of delivery of the liquid nitrogen in response to the temperature of the exhaust gas.