Method for loading pressurized liquefied natural gas into containers

A method for loading pressurized liquefied gas into a plurality of containers containing pressurized vapor, wherein the containers are loaded in succession, comprising the steps of:

• (a) introducing the liquefied gas into a first container, thereby discharging the vapor therefrom;
• (b) pressurizing the vapor discharged from the first container by passing the discharged vapor to a compressor, separating said pressurized vapor into a first vapor stream and a second vapor stream, passing the first vapor stream to a vapor utilization means, heating the second vapor stream and passing the heated second vapor stream into a second container of the plurality of containers to increase the vapor pressure in the second container;
• (c) passing vapor discharged from at least some of the containers to auxiliary storage tanks comprising a first tank and a second tank, withdrawing the vapor from at least one of the tanks, and passing the withdrawn vapor to the vapor utilization means;
• (d) regulating flow of fluids to and from the first and second tanks to buffer the flow rate of vapor to the vapor utilization means, wherein at the beginning of the method of loading the containers with liquefied gas, the first tank being filled with relatively high pressure vapor and the second tank containing pressurized liquefied gas, said fluid flow regulation comprising the steps of:
• (i) withdrawing pressurized liquefied gas from the second tank and passing the withdrawn pressurized liquefied gas to at least one of the containers and simultaneously withdrawing vapor from the first tank, pressurizing the withdrawn vapor and passing a first fraction of the pressurized vapor to the second tank and heating a second fraction of the pressurized vapor and passing the heated second fraction to the first tank, at the end of this step the second tank being substantially emptied of pressurized liquefied gas and containing relatively high pressure vapor and the first tank containing relatively low pressure vapor;
• (ii) withdrawing vapor from the second tank, pressurizing the vapor and passing a fraction of the pressurized vapor to the vapor utilization means and heating a second fraction of the pressurized vapor and passing the heated vapor to the second tank, at the end of this step the first and second tanks both containing vapor at a relatively low pressure;
• (iii) passing the vapor discharged from the last container being filled with pressurized liquefied gas to a compressor to pressurize the vapor, passing a first fraction of the pressurized vapor to the vapor utilization means and heating a second fraction of the pressurized vapor and passing the heated second fraction to the second tank, at the end of this step, the first tank containing vapor at a relatively low pressure and the second tank containing vapor at a relatively high pressure;
• and
• (iv) introducing pressurized liquefied gas into the second tank and discharging vapor therefrom, pressurizing the discharged vapor of this step and splitting the vapor into a first fraction and a second fraction, heating the first vapor fraction and passing the heated first fraction to the first tank and passing the second fraction to the gas utilization means, at the end of this step, the first tank containing vapor at relative high pressure vapor and the second tank containing pressurized liquefied gas.

A method for loading pressurized liquefied gas into a plurality of containers filled with vapor rich in methane, wherein the containers are loaded in succession, comprising the steps of:

• (a) introducing the liquefied gas into the containers, thereby discharging the vapor therefrom;
• (b) passing a first fraction of the vapor discharged from the container to a vapor utilization means;
• (c) passing a second fraction of the discharged vapor into auxiliary storage tanks comprising a first tank and a second tank, and passing at least a portion of the second vapor fraction from at least one of the auxiliary tanks to the vapor utilization means;
• and
• (d) controlling the amount of the first vapor fraction passed to the vapor utilization means relative to the amount of the second vapor fraction passed to the vapor utilization means to assure that the total flow rate of vapor to the vapor utilization means remains at a generally constant flow rate.