×

Plant and process for producing nitric acid

  • US 10,556,796 B2
  • Filed: 09/19/2017
  • Issued: 02/11/2020
  • Est. Priority Date: 09/19/2016
  • Status: Active Grant
First Claim
Patent Images

1. A plant for the production of nitric acid comprising:

  • (a) a reactor comprising at least one gas inlet for ammonia and compressed air, a combustion chamber provided with an ammonia combustion catalyst and configured to produce a burner gas stream comprising nitrogen oxides resulting from the combustion of ammonia and subsequent oxidation, and a gas outlet for burner gas;

    (b) a gas cooling section having a gas inlet which is in fluid communication with the outlet for burner gas of the reactor, said gas cooling section being configured to subject the burner gas stream to cooling, so as to form a cooled burner gas, the gas cooling section comprising a steam circuit heat exchanger configured to transfer heat from the burner gas stream to a steam circuit so as to generate superheated steam, and a gas outlet for cooled burner gas;

    (c) a condensation section having a gas inlet which is in fluid communication with the outlet for cooled burner gas of the gas cooling section, said condensation section being configured to subject the cooled burner gas to condensation so as to form an aqueous nitric acid condensate and an uncondensed nitrogen oxides gas stream, said condensation section having a liquid outlet for the aqueous nitric acid condensate and a gas outlet for the uncondensed nitrogen oxides gas stream;

    (d) an absorption section having a gas inlet which is in fluid communication with the gas outlet of the condensation section, said absorption section being configured to subject the nitrogen oxides gas stream to absorption in water, optionally in the form of a dilute nitric acid solution;

    said absorption section further comprising a liquid inlet which is in fluid communication with the liquid outlet of the condensation section and a gas outlet for nitrogen oxides tail gas;

    (e) a tail gas treatment system comprising a tail gas heating section, a nitrous gas removal section, and an expansion section, said tail gas treatment system being configured to subject nitrogen oxides gas to purification so as to form a purified tail gas and to subject said purified tail gas to expansion, said tail gas treatment section comprising a gas inlet for nitrogen oxides tail gas and a gas outlet for purified tail gas;

    wherein the tail gas heating section comprises a further heat exchanger configured to receive heat from the burner gas stream, said further heat exchanger being positioned downstream of the steam circuit heat exchanger, and upstream of the gas outlet for cooled burner gas, and wherein the reactor, the steam circuit heat exchanger, and the further heat exchanger are integrated into one single apparatus.

View all claims
  • 1 Assignment
Timeline View
Assignment View
    ×
    ×