Fors Varme Roskilde A/S wants to establish an 8 MW heat pump plant at Bjergmarken Renseanlæg based on a design and build contract. The preferred bidder will be awarded the contract for designing and building this heat pump plant as well as 10 years of maintenance thereof.

Bjergmarken Renseanlæg can as part of the tender procedure be inspected by interested applicants on 3.7.2019 from 11:00 am CET. The address of the location is: Boserupvej 25, 4000 Roskilde.

The procurement includes the establishment of an 8 MW heat pump plant at Bjergmarken Renseanlæg including setting up the construction area, preparation of the building for the plant, installation of equipment, installation of SCADA and control system for the operation and control of the heat pump plant as well as other electrical installations, training of personnel, delivery of operating and maintenance manuals, execution of appropriate tests as well as 10 years of maintenance of the heat pump plant.

The heat pump installation will be placed in an already existing sludge drying building at Bjergmarken Renseanlæg and the contractor is responsible for renovating the building, preparing it for installation of the heat pump plant, obtaining the necessary permissions while respecting relevant standards, rules, regulations and building codes.

The low temperature heat source for the heat pump is the cleaned waste water leaving the site, and the high temperature heat sink is the district heating grid in Roskilde. The contract consists of process works on waste water process, a secondary loop comprising heat exchanging and glycol loop, heat pumps, electrical and automation as well as district heating connection.

The plant must be designed for 8 MW heating production at the following design points:

Waste water inlet: 8oC, waste water outlet: 2oC, district heating supply temp: 80oC, district heating return temp: 52oC.

The plant must consist of at least 2 closed circuit ammonia separate heat pump units with a combined capacity as specified above, and the plant is expected to run full load approximately 7 500 hours per year and have an operating range of at least 8-22oC.

Heat extraction from the waste water requires an additional filter and establishment of a 400 m3 buffer sump as well as a new pipe installation including feed pumps from the waste water storage to the heat exchangers. A separate pipeline will have to be installed for each feed pump. On the district heating side of the heat exchanger pumps and piping must be dimensioned for maximum of 16 bars (PN16) and suitable for temperatures up to 90 oC. The pumpset should consist of n≥3 parallel pumps, with a total n-1 capacity of 100 % of the maximum capacity flow (e.g. 3x50% or 4x33%). The pumps should be able to regulate the total capacity in a way, so operation with any one of the heat pump units is possible.

The contractor will also be responsible for the supply and installation of all necessary electrical installations, including a control system where all technical installations must be fully connected to, and be able to exchange information with, the clients existing SCADA system (ABB 800XA).

Finally the contractor must supply and install all necessary safety equipment such as ammonia detection and emergency showers.