Switzerland-Japan headed Hitachi Zosen Inova AG (HZI), a global leader in waste-to-energy and renewable gas technologies, has announced that its subsidiary Hitachi Zosen Inova Steinmüller (HZI-STM) has signed a contract with German waste management company Zweckverband Müllverwertung Schwandorf (ZMS) for the supply of two new lines at Schwandorf waste-to-energy plant.
In 1982 ZMS commissioned the first three lines of the Schwandorf waste-to-energy (WtE) plant that was built by Steinmüller.
The WtE plant became one of the most important, system-relevant waste disposal companies in the region, disposing of waste from 17 towns and cities, districts, and special-purpose waste associations belonging to ZMS, with a total of 1.91 million inhabitants, as well as producing a major amount of energy to cover basic supply.
In 2010 another line was added to the plant. The WtE plant’s four incineration lines currently thermally treat around 450,000 tonnes of waste annually, converting it into electricity and heat.
The combined heat and power (CHP) plant supplies neighbouring industries with low-cost energy, feeds heat into Schwandorf’s district heating network, and electricity into the public grid.
Triphönix modernization project
As part of the Triphönix (Tri-Phoenix) modernization project, the three old Steinmüller boiler systems are now being dismantled after more than 40 years of service.
As part of the contract, the three lines will be dismantled by ZMS and replaced by HZI with two larger, state-of-the-art lines.
The contract for the EPC turnkey project, the value of which has not been disclosed, covers the combustion system and boiler, the flue gas treatment unit, the technical building equipment, EMCR and associated technology, structural engineering, and the necessary connections to the existing installations, relocation, and temporary arrangements for each line.
In the design phase, HZI came up with a well-thought-out installation plan in a constricted construction area allowing significantly more than the required throughput of 18 tonnes per hour (tph); each line will thermally treat 22 tph, which corresponds to a total throughput capacity of around 350,000 tonnes of waste per year for both.
This means that the two new lines must be installed precisely on the old site, even though the basic layout requires the steel structure and boiler house to be rebuilt.
Special features
Each boiler unit will have a thermal output of 67.2 MWth. Another special feature of the modernization concept is that parts of the old system will continue to be used. For example, the selective catalytic reduction (SCR) denitrification units deployed in the flue gas treatment system and the chimney system belonging to the plant.
The two new lines offer several special technical features. HZI has developed a boiler set-up concept tailored to the space requirements, which enables highly efficient energy utilization in the very limited space available.
This has been made possible, among other things, by intelligently arranging the superheater surfaces with an appropriately adapted boiler cleaning system that works based on modern shock-pulse cleaning in addition to the usual knocker cleaning.
Shock-pulse cleaning involves the use of targeted explosions to free the superheater packs from caking. The system thus permanently ensures efficient heat transfer, also reducing maintenance costs.
The steam parameters, 410°C and 73 bar(a), have been tailored to the client’s needs. The flue gas treatment system is designed for maximum separation using HZI’s proprietary SemiDry process, fulfilling the requirements of the new 17th BlmSchV ordinance and even falling significantly below its thresholds.
Maintain operations during construction
The project will run for 87 months and will be completed in 2031. To enable waste disposal to be maintained, the old lines will be dismantled, and the new lines will be built step by step while the remaining lines continue to operate.
This places special demands in terms of construction site safety, schedules, and logistics during the construction of the new lines.
HZI has however extensive experience with such complex modernisation projects. For example, it is currently working with GML – Gemeinschafts-Müllheizkraftwerk Ludwigshafen GmbH to deliver the similarly structured IGNIS project, where several lines are being dismantled and replaced with new ones over a total period of eight years while the plant continues to operate.
We are honoured that our customers have entrusted us to deliver these very extensive projects for them over such a long period of time, said Thomas Feilenreiter, VP of Systems & Service at HZI.
The Triphönix project is one of the largest investments in the history of ZMS and will further boost the plant’s importance in the region.
The Schwandorf waste-to-energy plant is systemically relevant for the region in terms of both waste disposal and energy supply. It was therefore important for us to find a partner that has experience in highly complex conversions and can draw on a broad range of expertise. This partner is HZI, commented District Administrator Thomas Ebeling, Chairman of the Schwandorf waste utilization association.
