“Honeywell’s Advanced Process Control with Profit Controller technology has increased process efficiency and improved our production rates, resulting in an investment payback of less than six months.”
Bernhard Geis, Plant Manager Ammonia Plant 4, BASF
Over the years BASF has continuously increased the ammonia production capacity of its ammonia plant no. 4 in Ludwigshafen, Germany. As the next step in gaining efficiencies, BASF considered implementing advanced process control (APC) technology at the facility. After a detailed analysis, the company chose to implement Honeywell’s advanced process control solution with Profit® Controller technology to increase production capacity. The following benefits were achieved:
BASF is the world’s leading chemical company. Its portfolio ranges from oil and gas to chemicals, plastics, performance products, agricultural products and fine chemicals. At the heart of the BASF Group is BASF SE headquartered in Ludwigshafen, Germany. With its over 200 chemical production plants, several hundred laboratories, technical centers, workshops and offices, it is the largest integrated industrial complex in Europe. Over an area of more than 10 square kilometers, some 33,000 employees work on the development, testing, manufacture and sale of thousands of different products.
As a reliable partner, BASF helps its customers in virtually all industries to be more successful. With its high-value products and intelligent solutions, BASF plays an important role in finding answers to global challenges such as climate protection, energy efficiency, nutrition and mobility. BASF has more than 95,000 employees and posted sales of almost €58 billion in 2007. BASF shares are traded on the stock exchanges in Frankfurt (BAS), London (BFA) and Zurich (AN).
The ammonia plant no. 4 is a Braun Purifier design commissioned in 1982. Feedstocks are natural gas, ambient air and water. Natural gas is also used as fuel for the gas turbine, driving the air compressor and as fuel for the burners of the primary reformer, together with off-gas from the process.
BASF sought a solution to utilize advanced process control technology at its Ludwigshafen facility. The main benefit desired by BASF was to increase capacity without increasing the specific gas consumption. The plant constraints for maximizing production strongly depend on ambient temperature. At higher ambient temperatures, production capacity is limited by the gas turbine, by aMDEA coolers on the CO2 wash column and by the exhaust fans of the primary reformer. At lower ambient temperatures, the steam turbine driving the synthesis gas compressor is limiting.
“We were at the next step in terms of gaining efficiencies at the plant and knew the only way to accomplish that was to implement advanced process control technology,” said Bernhard Geis, plant manager, BASF.
To attain its goal of increased production capacity, BASF chose Honeywell’s advanced process controller, Profit Controller. The implementation took about six months, and the total payback time was just under six months.
“I think the key success factors in our fast implementation and short payback time were the strong involvement of our process operations staff and a lot of cooperation and team spirit between our plant staff and Honeywell,” said Geis.
A single Honeywell Profit Controller was implemented to cover the following areas:
The choice for a single controller was motivated by a relatively low spread in dynamic response times and a tight coupling between the various sections of the plant.
After kickoff, several basic control loops were modified and optimized, yielding improved plant stability and controllability, which was necessary for a successful APC realization.
It was a challenge to integrate the air compressor gas turbine and the synthesis gas compressor steam turbine in the Profit Controller, as this equipment is not directly controlled by the DCS. This equipment has its own vendor-supplied control systems with only a few internal variables connected to the DCS without proper ‘anti-windup’ protection. A windup situation needed to be avoided as it can lead to unstable process behavior. Early detection of a potential windup situation (based on a process value deviation from a setpoint in combination with the valve position) proved to be effective.
“The most critical success factors in the implementation were the clearly defined and communicated goals throughout the stages of the APC implementation. In this project, we had a great team and cooperation between BASF operations, instrumentation experts, in-house process control consultants, as well as Honeywell local system engineers and APC experts. This enabled rapid implementation without any delays or any plant disturbances,” continued Geis.
Profit® is a registered trademark of Honeywell International Inc.