Impurity Control For A High Pressure CO2 Purification And Supply System

In a batch process for producing a purified, pressurized liquid carbon dioxide stream including distilling a feed stream including carbon dioxide vapor off a liquid carbon dioxide supply (10), introducing the carbon dioxide vapor feed stream into at least one purifying filter (13,14), condensing the purified carbon dioxide vapor feed stream within a condenser (18) to form an intermediate liquid carbon dioxide stream, accumulating the intermediate liquid carbon dioxide stream in a receiver (20), introducing the intermediate liquid carbon dioxide stream from the receiver (20) into at least on high-pressure accumulation chamber (30), heating the high pressure accumulation chamber (30) to pressurize the intermediate liquid carbon dioxide stream contained therein to a delivery pressure, delivering a pressurized liquid carbon dioxide stream from the high-pressure accumulation chamber (30), and discontinuing delivery of the pressurized liquid carbon dioxide stream for replenishing the high pressure accumulation chamber (30), wherein the improvement comprises:

• introducing the carbon dioxide vapor feed stream (L) into a distillation column (M) having packing (N) therein;
• condensing a first portion (0) of the carbon dioxide vapor feed stream (L) within a condenser (18) in fluid communication with the distillation column (M) to form another intermediate liquid carbon dioxide stream (T) and a liquid vent stream (Q);
• and
• introducing the another intermediate liquid carbon dioxide stream (T) into the receiver (20), and venting the liquid vent stream (Q) from a bottom of the distillation column (M).

In a batch process for producing a purified, pressurized liquid carbon dioxide stream including providing a liquid carbon dioxide supply (10), introducing a carbon dioxide vapor feed stream into at least one purifying filter (13,14), condensing the purified vapor feed stream within a condenser (18) to form an intermediate liquid carbon dioxide stream, accumulating the intermediate liquid carbon dioxide stream in a receiver (20), introducing the intermediate liquid carbon dioxide stream into at least on high-pressure accumulation chamber (30), heating the high pressure accumulation chamber (30) to pressurize the intermediate liquid carbon dioxide stream contained therein to a delivery pressure, delivering a pressurized liquid carbon dioxide stream from the high-pressure accumulation chamber (30), and discontinuing delivery of the pressurized liquid carbon dioxide stream for replenishing the high pressure accumulation chamber (30), wherein the improvement comprises:

• withdrawing a liquid carbon dioxide stream (A) from the liquid carbon dioxide supply (10);
• introducing the liquid carbon dioxide stream (A) into a distillation column (B) having packing (C) therein, and stripping volatile impurities from the liquid carbon dioxide stream with the packing;
• vaporizing the liquid carbon dioxide stream (A) in a sump (D) of the distillation column (B) for providing a carbon dioxide vapor;
• withdrawing from a vaporized portion (F) of carbon dioxide vapor in the sump (D) a first vapor stream (G) vented from the distillation column (B);
• withdrawing from the vaporized portion (F) of the carbon dioxide vapor in the sump (D) a second vapor portion (H) vented from the sump into a conduit (I);
• introducing the second vapor portion (H) in the conduit (I) into the carbon dioxide vapor feed stream upstream of the at least one purifying filter (13,14);
• introducing the carbon dioxide vapor feed stream (L) into a distillation column (M) having packing (N) therein;
• condensing a first portion (0) of the carbon dioxide vapor feed stream (L) within a condenser (18) in fluid communication with the distillation column (M) to form another intermediate liquid carbon dioxide stream (T) and a liquid vent stream (Q);
• and
• introducing the another intermediate liquid carbon dioxide stream (T) into the receiver (20), and venting the liquid vent stream (Q) from a bottom of the distillation column (M).