Ammonia
CEAMAG field of experience and interest concerns the revamping projects.
The Ceamag team is composed of highly skilled Process Engineers, Thermal and Mechanical Engineers, enabling us to bring to our Customers appropriate tailor made technical solutions for improvement in energy consumption, more production, less pollution.
CEAMAG experience covers:
Reformer Modernization
Ceamag provides a wide range of services for the modernization of reforming section for primary reformer furnaces, including Kellogg, GIAP or Foster Wheeler designs.
Ceamag’s Experts formerly worked for major petrochemical companies, specialising in furnace technologies and enjoy experience of more than 35 years with primary reformers for hydrogen, methanol and ammonia plants.
This document aims to describe the capabilities of Ceamag’s expertise, and the typical range of services that we render for a reforming modernization project.
In original Kellogg design at 1360 mtpd the temperature of flue gas leaving furnace is around 190°C.
After thirty years of operation the coil fins made of carbon steel are corroded and their performance reduces leading thereby to a higher flue gas temperature leaving the furnace.
Moreover Customers have often taken advantage of ammonia converter retrofit and installation of a hydrogen recovery unit to increase their ammonia plant capacity by approximately 10%.
The conjunction of coils ageing with capacity increase results in a higher flue gas temperature, which typically ranges between 260°C and 300°C in a Kellogg furnace. Because the price of natural gas is tending to rise on a long term basis, the loss of energy in flue gas has become or will soon become a major concern for many Customers.
While most Customers have managed to increase their ammonia plant capacity by around 10% without any change to the reforming section, the additional capacity increase will require investigating the behaviour of the reforming section in the new conditions and will possibly call for a debottlenecking of the reforming section.
Investigation concerns:
It is also critical to evaluate how the capacity increase will affect the energy consumption per ton of ammonia and try to optimize the reformer in this regard.
Many possibilities exist for modernizing a primary reformer which must be selected in function of project target (energy saving or capacity increase) and the particular condition of the plant.
For information the following possibilities are available:
Addition of a prereformer and a reheat coil (to compensate for the prereformer endothermal reaction, when natural gas is used);
Addition of a steam superheater coil below coil J aiming to reduce the superheater burners firing;
Addition of a feed preheater (process natural gas) coil in replacement of the fired heater 103-B. As a matter of fact feed preheater 103-B has a low efficiency and features high flue gas temperature;
Addition of mixed feed or process air coils in the cold leg to reduce the tunnel burners firing or to allow for heating of additional throughput;
COLD LEG UNDER COMPLETION
OPZ - UKRAINE
Addition of BFW coil below existing coil K if BFW temperature entering steam drum 101-F is less than design value;
Addition of process condensates coils (in combination with a steam or natural gas saturation unit: condensates recover the heat from the flue gas and evaporate in natural gas or process steam);
Installation of a combustion air preheater to bring the flue gas temperature down to 140°C (this solution provides the highest energy recovery because it reduces drastically the flue gas temperature);
PREREFORMER
KEMIRA - BELGIUM
In combination of various revamping steps inside the plant, Ceamag proposes a complete rearrangement of the convection section, leading to an optimisation of the energy saving at the primary reformer, applicable to any type of primary reformer. This was experience with the Odessa Port Plant Reference.
The primary reformer convection section has been redesigned by Ceamag taking into account of new decreasing of HP steam consumptions ( revamping of steam turbine of 103-J, Ceamag MUG Drying technology ), increasing of Ammonia production and requirement for shut-down of feed heater 103-F. This revamping strategy can be adapted for any 1360 tpd Kellogg type plant.
The design was performed and checked taking into account of transitory operation phases : start-up in its different steps and shut-down.
Any modernization project should be based on a recent test run of the reformer. The test run aims to collect the maximum quantity of operational data at the highest possible production capacity in order to capture a good picture of the reformer capability.
The test run requires the installation of additional measurement instruments (pressure gauges and temperature sensors in flue gas duct...) and this often proves to be difficult because the plant is in operation.
Consequently it is very usual to use the operating data of the plant which are available on DCS.
On the basis of the above collected data, Ceamag carries out a complete heat and mass balance with HYSYS software and deliver the following calculated data about existing operation:
These data are often accompanied by remarks explaining the deviation from the design value, these remarks can be helpful to operating engineers to optimize the current operation of the reformer.
This balance is submitted to Client for approval and then serves as basis of design for the modernization project.
Once the existing heat & mass balance is mutually agreed, Ceamag inserts the modifications that have been agreed with Customer and issues the HYSYS balance for revamped conditions.
Ceamag may at this stage suggests other or alternative modifications which could bring more benefits to Customer
After completion of the thermal engineering review, it is clear which coils must be replaced and which ones must be added.
Ceamag design services for the new coils include:
diate tubsesheet
KEMIRA – BELGIUM
When modernization involves more than the addition of new coils, Ceamag can specify the new equipment such as:
Along with the mechanical specifications and details of the new equipment, CEAMAG elaborates a complete Engineering Package for all parts affected by the modifications, including piping, instrumentation, electricity, civil works and steel structures, inside and outside Battery limits of the Reformer.
CEAMAG can perform the erection works and insures the supervision of erection, Precommissioining and Commissioning of the modified plant.
COILS ERECTION
OPZ - UKRAINE
CEAMAG field of experience and interest concerns the revamping projects.
The Ceamag team is composed of highly skilled Process Engineers, Thermal and Mechanical Engineers, enabling us to bring to our Customers appropriate tailor made technical solutions for improvement in energy consumption, more production, less pollution.
CEAMAG experience covers:
- Modernisation of reformers, radiant or convection section,
- Optimisation of front end plant operation,
- Revamping of CO2 removal section,
- Synthesis Loop optimisation,
- Process condensate treatment for full recycling as BFW,
- Optimization of LP steam consumption in production of cooling used for the Synthesis Loop.
Reformer Modernization
Ceamag provides a wide range of services for the modernization of reforming section for primary reformer furnaces, including Kellogg, GIAP or Foster Wheeler designs.
Ceamag’s Experts formerly worked for major petrochemical companies, specialising in furnace technologies and enjoy experience of more than 35 years with primary reformers for hydrogen, methanol and ammonia plants.
This document aims to describe the capabilities of Ceamag’s expertise, and the typical range of services that we render for a reforming modernization project.
MODERNIZING REFORMING FURNACES - KELLOGG TYPE CASE
- Optimization of energy consumption
In original Kellogg design at 1360 mtpd the temperature of flue gas leaving furnace is around 190°C.
After thirty years of operation the coil fins made of carbon steel are corroded and their performance reduces leading thereby to a higher flue gas temperature leaving the furnace.
Moreover Customers have often taken advantage of ammonia converter retrofit and installation of a hydrogen recovery unit to increase their ammonia plant capacity by approximately 10%.
The conjunction of coils ageing with capacity increase results in a higher flue gas temperature, which typically ranges between 260°C and 300°C in a Kellogg furnace. Because the price of natural gas is tending to rise on a long term basis, the loss of energy in flue gas has become or will soon become a major concern for many Customers.
- Capacity increase
While most Customers have managed to increase their ammonia plant capacity by around 10% without any change to the reforming section, the additional capacity increase will require investigating the behaviour of the reforming section in the new conditions and will possibly call for a debottlenecking of the reforming section.
Investigation concerns:
- the temperature limitations on the various points of the furnace (catalytic tubes temperature, coils wall temperature, ID fan 101-BJ suction temperature...);
- the pressure drop through catalytic tubes and through the tube side of coils;
- the flue gas quantity and pressure drop throughout the furnace to the suction of ID fan 101-BJ;
- the checking of coils performance in new conditions while increased throughput is required.
It is also critical to evaluate how the capacity increase will affect the energy consumption per ton of ammonia and try to optimize the reformer in this regard.
AVAILABLE TECHNOLOGIES
Many possibilities exist for modernizing a primary reformer which must be selected in function of project target (energy saving or capacity increase) and the particular condition of the plant.
For information the following possibilities are available:
Addition of a prereformer and a reheat coil (to compensate for the prereformer endothermal reaction, when natural gas is used);
Addition of a steam superheater coil below coil J aiming to reduce the superheater burners firing;
Addition of a feed preheater (process natural gas) coil in replacement of the fired heater 103-B. As a matter of fact feed preheater 103-B has a low efficiency and features high flue gas temperature;
Addition of mixed feed or process air coils in the cold leg to reduce the tunnel burners firing or to allow for heating of additional throughput;
COLD LEG UNDER COMPLETION
OPZ - UKRAINE
Addition of BFW coil below existing coil K if BFW temperature entering steam drum 101-F is less than design value;
Addition of process condensates coils (in combination with a steam or natural gas saturation unit: condensates recover the heat from the flue gas and evaporate in natural gas or process steam);
Installation of a combustion air preheater to bring the flue gas temperature down to 140°C (this solution provides the highest energy recovery because it reduces drastically the flue gas temperature);
PREREFORMER
KEMIRA - BELGIUM
- Combined optimization
In combination of various revamping steps inside the plant, Ceamag proposes a complete rearrangement of the convection section, leading to an optimisation of the energy saving at the primary reformer, applicable to any type of primary reformer. This was experience with the Odessa Port Plant Reference.
The primary reformer convection section has been redesigned by Ceamag taking into account of new decreasing of HP steam consumptions ( revamping of steam turbine of 103-J, Ceamag MUG Drying technology ), increasing of Ammonia production and requirement for shut-down of feed heater 103-F. This revamping strategy can be adapted for any 1360 tpd Kellogg type plant.
The design was performed and checked taking into account of transitory operation phases : start-up in its different steps and shut-down.
 |
BEFORE REVAMPING* * Existing situation before revamping of 103-J turbine Fuel Gas: 28 550 Nm3/h |
 |
AFTER REVAMPING* * Feed Gas Heater 103-B is stopped Fuel Gas: 24 331 Nm3/h |
CEAMAG’S RANGE OF SERVICES
- Record of operating data
Any modernization project should be based on a recent test run of the reformer. The test run aims to collect the maximum quantity of operational data at the highest possible production capacity in order to capture a good picture of the reformer capability.
The test run requires the installation of additional measurement instruments (pressure gauges and temperature sensors in flue gas duct...) and this often proves to be difficult because the plant is in operation.
Consequently it is very usual to use the operating data of the plant which are available on DCS.
- Analysis of the existing operation
On the basis of the above collected data, Ceamag carries out a complete heat and mass balance with HYSYS software and deliver the following calculated data about existing operation:
- Fuel gas consumption in each location (arch, tunnel, superheaters and auxiliary boiler burners);
- UxA of each coil (heat transfer coefficient x total heat exchange area);
- Flue gas temperature profile throughout the duct
These data are often accompanied by remarks explaining the deviation from the design value, these remarks can be helpful to operating engineers to optimize the current operation of the reformer.
This balance is submitted to Client for approval and then serves as basis of design for the modernization project.
- Engineering study for reformer modernization
Heat and mass balance in revamped conditions
Once the existing heat & mass balance is mutually agreed, Ceamag inserts the modifications that have been agreed with Customer and issues the HYSYS balance for revamped conditions.
Ceamag may at this stage suggests other or alternative modifications which could bring more benefits to Customer
Review of primary reformer radiant section
Ceamag has access to REFORM software which is
regarded as one of the most powerful tool for the modelling of radiation
section. Ceamag is then able to check the operation of radiant section
in revamped conditions. Checking includes:
- the heat release in arch burners;
- the catalytic tube wall temperature;
- the methane slip at primary reformer exit;
- the process gas pressure drop through the tubes;
- the flue gas temperature at radiant section outlet.
Design of new coils
After completion of the thermal engineering review, it is clear which coils must be replaced and which ones must be added.
Ceamag design services for the new coils include:
- Coil fabrication drawings with tubes and manifolds specification, intermediate tubesheets drawing;
- Coil pressure part design calculations;
- Detailed modifications to the carbon steel casing, header boxes, ladders, platforms, piping and refractories;
- Coil erection procedure.
diate tubsesheet
KEMIRA – BELGIUM
Specification of other equipment
When modernization involves more than the addition of new coils, Ceamag can specify the new equipment such as:
- Air preheater;
- Arch burners;
- Auxiliary boiler burners;
- Blowers.
Detail Engineering Package
Along with the mechanical specifications and details of the new equipment, CEAMAG elaborates a complete Engineering Package for all parts affected by the modifications, including piping, instrumentation, electricity, civil works and steel structures, inside and outside Battery limits of the Reformer.
Erection works and shut-down optimization
CEAMAG can perform the erection works and insures the supervision of erection, Precommissioining and Commissioning of the modified plant.
COILS ERECTION
OPZ - UKRAINE
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