**4. Design aspects that minimize the adhesion of biofouling**

The design of the heat exchanger can represent an important factor to minimize the presence of biofouling on its surfaces. The main design variables that intervene in the biofouling growth process are [27]:


Although it is very difficult to relate the colonization of the surface with only one of these variables, it can be affirmed that they all have their influence on the process of developing the biofilm on the surface in contact with seawater. In this way, it is recommended to maintain minimum flow rates above 0.9 ms<sup>−</sup><sup>1</sup> and use smooth surfaces and high temperatures (>90°C). Otherwise, the presence of biofouling on the heat exchange surface is unavoidable.
