Waste-to-energy plant upgrades emission monitoring

Fernwärme Ulm GmbH (FUG), operator of the Zweckverband Thermische Abfallverwertung Donautal (TAD), is the district heating supplier for the city of Ulm. The core competencies of FUG include the operation, maintenance and optimisation of production and distribution systems. About half of the population of the city of Ulm is supplied with heat from FUG’s broad district heating network.

Two years ago, the company invested in the renewal of its emission measuring equipment at its waste incineration plant.

The project tender placed strict requirements on all participating bidders. The goal was to replace the outdated equipment with new high-performance and futureproof technology, which would fulfil the requirements for approved emission measurement devices in all aspects.

“We convert 160,000 tons of household waste per year into energy,” said Hubert Vogel, Deputy Manager MHKW Müllheizkraftwerk. “All the waste comes from Ulm and the bordering municipalities along the Danube valley with a population of around one million. From that we can guarantee the supply of heating for around 50% of the residents of the city of Ulm. For the emission measurement associated with that, we need reliable low-maintenance emission measurement equipment.”

Key criteria in the assessment process for the renewal of a measurement system that was over 20 years old included:

• Fast delivery of spare parts if needed: the current system of spare parts delivery did not fulfil the listed requirements.
• Minimisation of operating and maintenance costs: the old devices were generating exceedingly high costs.
• Availability of more than 97% during annual operation to meet the legal requirements for quality assurance.
• Improved measured value stability with reduced pollutant limit values.
• Increased operational efficiency.
• Long maintenance interval to minimise maintenance cost.

Having assessed all the aspects of the supplier evaluation, FUG decided to select ABB. By investing in the stable ACF5000 CEM System, FUG’s pollutant emission monitoring is state of the art, while operating costs have decreased at the same time.

ABB had introduced the first FTIR spectrometer for emission measurement 25 years ago, and the ACF5000 is the fourth generation of the system. The system can measure up to 15 gas components simultaneously while providing clearly improved measurement characteristics, such as the measurement of HCl, CO₂, NH₃, NO_x, SO₂, CO and O₂.

”The ACF5000 CEM System was installed in 2018,” said Vogel. “The measurements are very stable and run flawlessly. For the legally required QAL3 monitoring, in accordance with EN 14181, internal validation cells are used, so no maintenance times or downtimes occur as a result. I even think that the ACF5000 is working much better than expected.”

The ACF5000 uses the FTIR technology developed at the ABB Québec plant and Frankfurt plant in continuous gas analysis, which also includes in-house system construction.

The ACF5000 provides a complete turnkey system, from sampling to measured value, and has approvals in accordance with DIN EN 15267 and DIN EN 14181. With a certified maintenance interval of six months by TÜV-Rheinland, and 12 months (MCERTS) by CSA/SIRA in England, the ACF5000 is claimed to be the first multicomponent emission device which has obtained a certified 12-month maintenance interval.

“Since the waste incineration plant in Ulm has been demonstrating the lowest emission limit values in all of Germany, special procedures were required when implementing this project,” Vogel continued. “It was a risky move for FUG GmbH to place our bets on the newly developed ACF5000, yet ABB was absolutely confident from the very start that it would meet the requirements.

“As in any project, there were issues, but there was never an issue that we could not solve with ABB. Therefore, we see no other alternative than the ACF5000 to monitor emissions in a stable and reliable manner.

“In that regard, cooperation with ABB is very good and that is one of the most important success factors,” he added.