Low Temperature Shift (LTS) Guard with Waste Heat Recovery

The installation of an additional Low Temperature Shift (LTS) guard reactor before the LTS converter (see Figure below), can reduce the CO slippage without increasing the pressure drop. The CO slippage can be reduced from about 0.25-0.30% to about 0.10-0.15% ( Indian FlagFor Indian plants the reduction is stated to be from 0.2-0.4 to 0.1-0.2 % - FAI, 2013). A lower CO slippage results in increased ammonia production, as less hydrogen will be consumed in the methanator for converting all carbon oxides into inert methane. For the same ammonia production the feedstock use can be decreased. This results into lower steam requirements (CDM, 2006). This measure also reduces the inerts and reduces the need for purging from synthesis loop (FAI, 2013).

With the implementation of this measure, the temperature in the LTS converter can be better controlled and the waste heat recovery improved with the installation of a boiler feed water preheater between the LTS guard and the LTS converter (CDM, 2006).

Indian Flag This measure has been implemented in six ammonia plants in India (FAI, 2013). 

Development Status Products
Commercial
Ammonia

Low Temperature Shift (LTS) Guard with Waste Heat RecoveryCosts & Benefits

Parent Process: Shift Conversion
Energy Savings Potential
CO2 Emission Reduction Potential
Costs

Indian flag For a 1 500 tpd plant, the necessary investment is in the range of US $1 million [2005 values] (FAI, 2013).

Low Temperature Shift (LTS) Guard with Waste Heat RecoverySchematic

Low Temperature Shift (LTS) Guard with Waste Heat Recovery Publications

Reduction in Steam Consumption Through Revamping of Ammonia Plant of Indian Farmers Fertilizer Cooperative Ltd. (IFFCO) Plants

This project design document prepared as part of UNFCCC's Clean Development Mechanism (CDM) provides details for measures to reduce steam consumption in an Indian Ammonia production plant. 

Low Temperature Shift (LTS) Guard with Waste Heat Recovery Conference Papers

Energy Efficiency Gains in Indian Ammonia Plants – Retrospect and Prospects

The paper documents the major efforts behind energy efficiency improvements in Indian ammonia plants which include use of better feedstock, revamp and retrofit and adoption of better operation and maintenance practices. The paper also outlines the potential for further energy savings and measures required for the same including feedstock change, revamp/retrofit and optimization of critical operating parameters.

Energy Efficiency Gains in Indian Ammonia Plants – Retrospect and Prospects

The paper documents the major efforts behind energy efficiency improvements in Indian ammonia plants which include use of better feedstock, revamp and retrofit and adoption of better operation and maintenance practices. The paper also outlines the potential for further energy savings and measures required for the same including feedstock change, revamp/retrofit and optimization of critical operating parameters.