High pressure front-end ammonia plant. Suitable for production between 2500 and 4500 t/d.
- Referenced and reliable steam reforming process
- Energy efficiency up to 6.5 gcal/t
In the A3000 process, the steam reforming section operates at a pressure of about 60 bar, and the air for the secondary reforming is introduced in stoichiometric amounts.
The high reforming pressure substantially reduces the synthesis gas compressor duty and boosts the efficiency of the carbon dioxide removal section, resulting in significant efficiency gains. It also enables the use of a single-stage, single-body synthesis gas compressor, with half the compression ratio and two thirds the power consumption of what would be needed for a conventional process. So a compressor designed for a conventional 2000 MTD plant is entirely suitable for a 3000 MTD of the A3000 plant process. As such there is no need to install any additional synthesis converter and ammonia separation equipment between the compressor make-up stages to relieve the load on the machine. Additionally, and distinct from the excess air-based ammonia process designs, the A3000 neither requires an excess nitrogen removal unit, nor an oversized air compressor train.
Another feature of the A3000 process is the installation of a turbine to drive the air compressor machine and to produce electricity. This electricity will be used to provide a partial electrification of the small driver often otherwise installed and driven by inefficient small steam turbines in standard ammonia plants.
Part of the steam is also exported to Urea plant main user (such as the CO2 compressor) to provide an efficient use of the energy recovered and produced in the ammonia plant.
The main steps of the A3000 are the same of a standard plant namely:
- Primary and secondary reforming
- HT and LT shift conversion
- CO2 removal
- Synthesis gas drying
- Ammonia synthesis
- Hydrogen recovery
The key features of the A3000 are:
- Front end operated at 60 bar
- Single body synthesis gas compressor
- Single ammonia converter configuration
- Partial electrification of the plant
- Integration with Urea plant
The energy consumption of the plant can be up to 6.5 Gcal/h.