POX

The POX process design is suitable for syngas production in a single line up to 70'000 Nm3/h of CO+H2 (equivalent ot a production of 600 t/d of MEG).
It is referenced up to 26'000 Nm3/h of CO+H2.

The steam reforming through Partial Oxidation (POX) is Casale’s process for synthesis gas generation from natural gas and oxygen from Air Separation Unit (ASU). The main feature of POX process is to produce, with a minimum steam requirement, a syngas rich in CO and H2 and with a low content of CO2 and a minimum methane slip. The typically H2:CO ratio ranges from 2 to 1 depending on downstream units requirements.The syngas with such charachteristics is suitable for HYCO plants, MEG plants, FT units and methanol plants revamping.
The POX process for syngas generation is based on the natural gas partial oxidation through pure oxygen burners inside a gas generator, which is a pressure vessel lined with refractory material. The performances of the POX unit to achieve the best possible conversion of natural gas to CO and H2 are enhanced by application of Casale technologies and tailored process solutions.
The main steps, as shown in the block flow diagram, are:

  • Natural Gas Desulphurization
  • Synthesis gas generation through POX reactor
  • Heat recovery and cooling
  • Syngas washing section
  • CO2 removal Section (optional)

Embedded Casale’s technologies

Casale’s well-proven and highly efficient POX Burner, which is technological core of the unit, is the proprietary item for the unit. The optimized burner design guarantees an efficient conversion with soot-free operation at various plant loads, also with fluctuating feed gas composition and with "difficult" fuels.

Key features

The POX Unit process design is characterised by high reliability, superior performances, streamlined design for cost effectiveness and limited environmental impact. The design can be customized to specific Client’s needs and integrated any downstream unit.
The process is extremely flexible, and the scheme may be adapted to specific market needs and/or customer requirements. Other distinctive features are:

  • The syngas composition is in the range, in terms of H2:CO ratio, between 2 to 1
  • The steam to carbon ratio is in the range between 0.2 to 0.8 Nm3/Nm3
  • The oxygen consumption is in the range of 0.4-0.5 Nm3/Nm3 H2+CO
  • The saturated steam production is in the range 1.1-1.3 Mton/kNm3 H2+CO
  • The minimum turn-down ratio is very low; operation is stable at only 20% of design
  • Very compact and simple lay-out, arranged in a way to minimize the overall footprint as well as optimize the connections across the different sections of the plant
  • Primary importance is given to the process control, as the safety and reliability of the plant as well as its efficiency and economics depend on it
  • Full life-cycle support by means of Casale’s Remote Plant Monitoring and/or Casale’s Customer Care services

Technologies