SAACKE equips a new district heating plant in Vienna with burners for low NOx emissions and flexible operation
Unique in Europe in this magnitude
For the development of Austria’s largest district heating grid, utility company Wien Energie GmbH planned the construction of a new peak load plant with a maximum firing rate of 360 MW. In order to remain well-equipped for the future reductions of the associated legislation, the new construction in the center of Vienna had to be in compliance with the strict emission requirements. The plant engineer ANDRITZ AG commissioned SAACKE GmbH to install twelve DDZGG-LN steam pressure jet burners. The burners not only fall below the emission requirements, they also enable flexible fuel operation. This was realized by combining high firing rate, low-emission burners, an individual burner control system and a high control range and is unique in Europe in this size.
The two hot water boilers were each equipped with six DDZGG-LN burners, each with a max. firing rate of 30 MW, and are controlled by an individual burner control system. Light fuel oil (LFO) and natural gas H can be used simultaneously or independently, which enhances the flexibility for the operator. A high control range of 1:6 in gas mode and 1:5 in oil mode, low excess air and a low flue gas recirculation volume ensures economical and efficient operation. The emissions account for max. 70 mg NOX/m3 and 10 mg CO/m3 for natural gas H and not exceed 110 mg NOX/m3 and 10 mg CO/m3 for LFO. The order volume included the burners as well as gas and oil supply/control, burner safety technology, ignition and cooling air supply for the burners and boilers, commissioning and service beyond the conclusion of the project. The burners are designed for 72h operation without constant monitoring in accordance with the Austrian law on the operation of steam boilers (ABD-V). Low maintenance costs and long service life additionally increase economy. “Compliance with the defined limit values and comprehensive service during commissioning and operation were essential for successful project implementation. The SAACKE burners ensure that our customer is well-equipped for the future. They fall well below the strict requirements specified by the Austrian emissions law EG-K 2013,” says Nikolaus Dobrowsky, Project Manager at SAACKE GmbH. In the meantime, the DDZG(G)-LN burner series has been further developed and replaced by the SAACKE ATONOX.
From trial to emergency operation: reliability of supply 100% guaranteed
The tight schedule, which provided for an integration into active operation, was a challenge: the commissioning phase and the trial operation were scheduled for the main operating period between January and March. The generated quantities of heat had to be coordinated with the district heating grid. Since the heating station acts as a reserve in case of failure of other heating plants, the operator also required a run-up time from standstill to full load operation of within 30 minutes. This requirement was tested in an emergency operation during the trial period, but posed no problems for the SAACKE burners.
