PROCESS FOR CRYOGENIC PURIFICATION OF HYDROGEN

• US 3,628,340 A
• Filed: 11/13/1969
• Issued: 12/21/1971
• Est. Priority Date: 11/13/1969
• Status: Expired due to Term

• Current Assignee: HRI, Inc. (Japan) (Canon Inc.)
• Original Assignee: Banikiotes Gregory Christ, Baush Edward Harold Van, Joseph Meisler
• Inventors: Meisler, Joseph, BAUSH EDWARD HAROLD VAN, BANIKIOTES GREGORY CHRIST
• Application Number:
  US04/876,294
• Time in Patent Office: 768 Days
• US Class Current: 62/618
• CPC Class Codes: C01B 2203/046 Purification by cryogenic separation
• CPC Class Codes: C01B 2203/048 the impurity being an organic compound
• CPC Class Codes: C01B 2203/0495 the impurity being water
• CPC Class Codes: C01B 3/506 at low temperatures
• CPC Class Codes: F25J 2205/40 using hybrid system, i.e. combining cryogenic and non-cryogenic separation techniques
• CPC Class Codes: F25J 2205/60 using adsorption on solid adsorbents, e.g. by temperature-swing adsorption [TSA] at the hot or cold end
• CPC Class Codes: F25J 2210/12 Refinery or petrochemical off-gas
• CPC Class Codes: F25J 2220/60 Separating impurities from natural gas, e.g. mercury, cyclic hydrocarbons
• CPC Class Codes: F25J 2270/90 External refrigeration, e.g. conventional closed-loop mechanical refrigeration unit using Freon or NH3, unspecified external refrigeration
• CPC Class Codes: F25J 3/062 Refinery gas, cracking gas, coke oven gas, gaseous mixtures containing aliphatic unsaturated CnHm or gaseous mixtures of undefined nature
• CPC Class Codes: F25J 3/0635 separation of CnHm with 1 carbon atom or more
• CPC Class Codes: F25J 3/064 separation of CnHm with 2 carbon atoms or more
• CPC Class Codes: F25J 3/0655 separation of hydrogen production of hydrogen containing gas in general C01B3/00, e.g. separation of hydrogen or hydrogen containing gases form gaseous mixtures at low temperatures C01B3/506
• CPC Class Codes: Y10S 62/932 From natural gas

Abstract

A process for separating condensable contaminants such as methane from a crude hydrogen stream utilizing a series of multipass heat exchangers through which the gas flows for stepwise cooling, with interstage separation of condensates which are expanded and passed in a reverse flow path for autogenous refrigeration. Supplemental refrigeration is provided for the last cooling stage to maintain the plant in proper heat balance for variations in feed gas composition and to facilitate startup.

Claims

2. The process of claim 1 wherein the partially cooled gas stream from step (b) is further cooled to about at least as low as -30* F. by a first external heat exchange means.