Tuesday, 26 September 2017

The chemical and petrochemical sector is the largest industrial energy consumer. Ammonia production is responsible for about 17% of the energy consumed in this sector. In 2004, the ammonia manufacturing industry consumed 5.6 EJ of fossil fuels, of which 2.7 EJ was for energy and 2.9 EJ for feedstock use.1 Although the energy use per tonne of ammonia has decreased by 30% over the last thirty years, adopting best available technologies (BAT) worldwide can further reduce energy use by 20-25%1, 2 and decrease greenhouse gas emissions by 30%.2

Technology or MeasureEnergy Savings PotentialCO2 Emission Reduction Potential Based on LiteratureCostsDevelopment Status
Using Improved Materials for Reformer Tubes
Replacement of the reformer tubes in the Indian plant required an investment of Rs. 50 million. The payback time was 40 months (PCRA(link is external),, 2009 p.335).
Indian Flag  Investments for a 1 300 tpd plant are around US $ 2 million [2011 values] (FAI, 2013).
Commercial
Heat Recovery from Reformer Flue Gas
Reducing the stack temperature by 100˚C will result in energy savings of approximately 0.4 GJ/ t NH3 (Christensen, 2001).
Indian Flag By installing a feed pre-heat coil in the low temperature convection section of the reformer flue gas duct, a plant in India was able to reduce flue gas temperature of the reformer from 170˚C to 148˚C and eliminated the need for a fired heater, resulting in energy savings of 0.17 GJ/t NH3 (Nand and Goswami, 2009(link is external)). 
Indian Flag Another Indian installed a natural gas heating coil to recover the heat from the reformer flue gas. The reformer flue gas temperature was reduced from 190˚C to 160˚C, saving 0.18 GJ/t NH(Nand and Goswami, 2009(link is external)). 
At an ammonia plant in Pakistan, a demineralized water preheating coil was installed to recover heat from the flue gas (240˚C). The temperature of the flue gas was lowered to 137˚C, recovering approximately 44 GJ/hour of waste heat from the flue gases (Yousaf, 2011)
Heat recovery in the Pakistani plant saved $ 2 Million/year (Yousaf, 2011)
Indian Flag For a 1 300 tpd plant, the required investments are estimated to be around US $ 700 000 [2008 values] (FAI, 2013).
Commercial
Using Improved Catalyst Designs for Primary ReformingCommercial
Improving the Design for Induced Draft Fan Ducts
Indian Flag For a 1 500 tpd plant, investments are estimated at around US $ 200 000 (FAI, 2013).
Commercial
Heat Exchange Autothermal Reforming
The investment cost are stated to be 303 Yen/tonne ammonia, resulting in a payback time of one year (1999 figures) (ECCJ, 1999, 148).
Commercial
Increasing Reformer Operating PressureCommercial
Modification of Burners in Primary Reforming
Indian Flag  Replacement of burner nozzles for a 1 500 tpd plant is estimated to cost around US $ 0.4 million [2012 values] (FAI, 2013)
Commercial
Using an Adiabatic Pre-reformer
Energy consumption can be reduced by 4-10% (IPTS/EC, 2007; Nieuwlaar, 2001; Patel et al., unknown date)
Dutch flag In Netherlands, a plant in Rozenburg, energy savings of about 4% were realized with the installation of an adiabatic pre-reformer. (Worrell and Blok, 1994). 
For a 2 000 t/day plant, the investment cost associated with the installation of a pre-reformer is reported to ¥280 million, resulting in a payback time of 1.7 years (ECCJ, 1999 p. 156). 
According to Nieuwlaar (2001) the investment cost is estimated at €7.5/GJ. 
Dutch flag For the plant in Netherlands, the installation costs for the adiabatic pre-reformer was estimated as $6/tonne ammonia, and the payback time was estimated to be  one to three years (in 1990 dollars) (Worrell and Blok, 1994).
Indian Flag For a 1500 tpd plant, the investments are in the range of US $ 10 million (2000 values) (FAI, 2013).
Commercial
Insulation of Reformer Furnace
An assessment for an Australian ammonia plant estimated that the payback time for improving insulation on reformer furnace will have a payback time of less than one year (Australian Government, 2009). 
Commercial
Improved Design of Secondary Reformer Burner
Indian Flag The cost of replacing burner nozzles in a 1 500 tpd plant is reported to be around US $500 000(FAI, 2013).
Commercial
Using Improved Catalyst Designs for Secondary ReformingCommercial
Shifting Reformer Duty
This measure increases the capital costs (FAI, 2013). 
Commercial
High Emissivity Coating of Radiant Section Refractory
Indian Flag For a 1 500 tpd plant, the implementation costs are estimated to be around US $ 25 000 FAI, 2013). 
Commercial
Heat Exchanger Reformer
Lower Steam to Carbon Ratio on ReformerCommercial
Installing a Feed Gas SaturatorCommercial
Increasing Mixed Feed Preheat Temperature
Indian Flag For a 1 500 tpd plant, an investment in the range of US $ 500 000 is required to preheat fuel gas using low grade recovered heat (FAI, 2013)..
Commercial

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