Heat exchanger intended for the heat recovery in their thermomechanical pulp (TMP) production process
SACOME has been awarded by one of the most important multinational corporations in the pulp and paper industry with a contract for the supplying of a heat exchanger intended for the heat recovery in their thermomechanical pulp (TMP) production process.
As part of their paper production process, the pulp mill is rinsed with water and, at a later stage, it must be discharged to the biological treatment plant. As reported by our client, in the event that the temperature exceeds 50 ºC, the biological organisms consumption can rise considerably due to a loss in efficiency.
Our Technical Department have faced different challenges: firstly, to cool down this solids-rich effluent under 50 ºC, carrying it out by means of a configuration able to minimize the risk of plugging, thus preventing the number of shutdowns. A further target was to adopt a solution so that a certain amount of energy could be recovered from this rinsing water, providing the effluent, in this way, a significant added value. At last, our staff had to choose the most suitable geometry for such a high capacity, 360 m3/h.
Having assessed different alternatives, we recommended the client one of the configurations within the SACOME Industrial Line, we are referring to our I-TF20-I heat exchanger. This tubular heat exchanger consists of 2 concentrical tubes, in which the effluent, that can have large-size particles, flows through the inner tube, whilst the service water is processed in the annular space.
Our technical solution
With the aim to achieve a workable technical solution, able to process such a high rinsing water flowrate, the approach of our Technical Department is based on 4 lines in parallel, having collectors at the inlet and outlet to split the production capacity. Moreover, having in mind the limited available floor space and to make easier the transportation to Norway, our Projects Department have designed a frame with modular construction.
At last, it’s worth noting that there is a huge energy saving of 9.000.000 kcal/h, which contributes to shorten the investment payback.
Heat exchagers technical documentation
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