In addition to its own and external products, system providers involved in the project business also provide process knowledge and complete projects refined to the last detail. The standard is high. Their own knowledge combined with the supplier’s knowledge leads to a complete solution. From the delivery of the components to their installation, trial operation and commissioning, all the building blocks have to be coordinated.
sera demonstrated just such ability when it was entrusted with the decarbonisation of the make-up water circuit of a waste-to power plant.
Incinerators generate heat during the combustion process which is used to generate electrical and thermal energy. At Enertec in Hameln the condensation heat produced during the power generation process is let off into the atmosphere via wet cooling towers. These cooling towers use the principle of evaporation and need the respective amount of make-up water for the cooling circuit.
The water volume (between 120-200 m³/h) varies with the heat to be dissipated and the ambient temperature. In order to prevent damage to the cooling circuit due to the build up of CaCO3 (calcium carbonate) during the evaporation process, this water needs to be decarbonised.
The hydrogen carbonates contained in the make-up water are converted to carbonic acid by dosing sulphuric acid. By spraying the treated make-up water from the cooling tower at the head of the wet cell type cooling system, the carbonic acid is released in the form of carbon dioxide.
Together with MEDORA from Sarstedt near Hanover, sera delivered the following items for the new wet cell type cooling system:
- Acid storage consisting of 20 m³ and 30 m³ storage tanks with collecting basins for sulphuric and hydrochloric acid. They have been installed outdoors where the respective media are directed via lifting pipes into collection containers, with vent and breather pipes located in the basement area of the water treatment.
- A dosing station for feeding H2SO4 into the untreated water including a static mixer unit.
- Continuously operating measuring device for monitoring/regulating the K S4,3 value in the cooling tower make-up water and cooling tower circuit water downstream of the acid station. This includes, amongst other things, a sampling pipeline, a process analysis for determining the cyclic K S4,3 value and a pH measurement of the K S4,3 to ensure an adequate pH value after mixing.
- Modern desalinisation system storage tanks and dosing system for hydrochloric acid, converted from the existing units.
- A filling device for the unloading of trucks including an underground discharge pipeline for discharging the filling pipeline into the respective storage containers.
- A HCL reservoir and exhaust air scrubber with collecting basin and fresh air ventilator.
- All necessary fittings and measuring devices as well EMSR technology designed by profibus.
- All connecting pipelines.
In addition to the compliance with the relevant DIN, IEC, VDI, VDE standards and the EC Machinery Directives, the scope of supply and services also included the training of personnel on site.
When controlling the titrimetric measurement method to be used, a K S4,3 value of exactly 0,5 -0,1 mmol/l had to be observed after dosing the acid into the cooling tower makeup
water. The observance of this value was critical for the final approval.
For sera as a system provider for such a problem, it was not only important to arrange the required components beyond its own scope of delivery but to also look at different ways to solve the problem.
The starting point was the analysis of the untreated water. The entire chemical process together with its corresponding measuring methods had to be worked out. At the same time it was necessary to work in closely with the plant construction team.
The co-operation enjoyed between sera and MEDORA was the result of previous experiences which again proved extraordinarily successful in this case. In addition to a production process that followed a very exact schedule and which had to match the construction schedule, intensive support at individual construction stages had to be realised.
This task was only accomplished because of perfect teamwork between planner, manufacturer, plant constructor and operator.
The following technical documents were available shortly after the contract was awarded.
- Technical drawings of the dosing systems, sampling points, storage containers and collection containers
- List of components
- Connecting and cable diagrams for the installation of power and control lines
- Schedule for the production of main components as well as for all suppliers
- Operating Instructions
The successful completion of a project of this scope requires all participating companies to assign competent contact partners right from the outset. They must communicate effectively with all parties to ensure success.
sera, together with its partners, was able to successfully realise this project for the incineration plant in Hameln through just such communication and teamwork.