Commercial/Industrial, Municipal Solid Waste, Wastewater/sewage/sludge
Upgrading to a waste-to-energy plant.
Zweckverband Abfallwirtschaft Raum Würzburg (ZVAWS), the waste management association of the greater Würzburg area, is undertaking a project for the upgrading of line 1 at the Würzburg Müllheizkraftwerk waste-to-energy (WtE) plant. The incineration plant treats waste from households, businesses and industry.
On 20th July 2018, ZVAWS awarded Martin GmbH the design contract for the partial replacement of line 1 of the plant. Under the contract, Martin is to plan the scope of services to be performed: dismantling of the existing steam generator and grate as well as various auxiliary units in line 1; erection of a new grate-based combustion system consisting of the Martin reverse-acting grate and associated steam generator, installation of various media pipes, and the electrical instrument and control system technology, as well as replacement of the switchgear for line 2. Planning must take into account that lines 2 and 3 need to continue to operate while replacement work is in progress.
The new line is to be designed for a gross heat release of 29.2 MW, an average heating value of 10,500 kJ/kg and a waste throughput rate of approximately 10 tonnes per hour, while at the same time providing for the co-combustion of a certain amount of sewage sludge.
A binding contract for the implementation of planning work is yet to be awarded. This is expected to take place when design work has been completed, the permit has been obtained and the members of ZVAWS have approved partial replacement, probably in June 2019.
The estimated cost of the project is about €30 million.
The plant currently has a total waste capacity of 215,000 tonnes per year. The input consists of approximately 65,000 tonnes of municipal waste from the association area, 85,000 tonnes from five counties in Middle Franconia and Baden-Württemberg, 30,000 tonnes of commercial waste, and about 6,000 tonnes of sewage sludge (co-incineration).
Separately, at the end of July 2018, ZVAWS reported that it is considering building a fourth mono-combustion incineration line with fluidised-bed firing for sewage sludge at Faulenberg. Legislation requires that sewage treatment plants, with a size of 50,000 population equivalents, must recover phosphorus from the sewage sludge no later than 2029 in order to use the natural resource and secure the long-term supply of fertiliser. However, no decision has been made yet regarding this project.