In accordance with ISPRA and the Ministry of the Environment indications, the main water discharges of the “FSRU Toscana” Terminal are continuously monitored; in particular, the discharge dedicated to the regasification process, where chlorine residuals and discharge temperature are continuously monitored.
Chlorination is the chemical antifouling method mostly used worldwide for its effectiveness at all levels, both civil (drinking water) and industrial (cooling circuits with sea water, fresh water or sewage).
Chlorination in the sea/water circuits is carried out by dosing sodium hypochlorite (NaClO) produced on board with the sea water electrolysis. Therefore, this process does not require to add chlorine in the sea water but it transforms the chlorine present in sea water in a substance useful to perform the antifouling function.The quantities of free active chlorine released into the sea are significantly lower in the main discharge than those prescribed by national regulations for discharges in water (Testo Unico Ambientale). Furthermore, the levels of discharge of this parameter were carefully valued by the competent Authorities, which issued the necessary authorizations. Finally, the concentration of free active chlorine is continuously monitored by OLT and the Authorities. In particular, it is provided a continuous monitoring of the main drainage.
The temperature variations of the sea water were analyzed by the competent Authorities during the authorization process and they will be continuously monitored by OLT and the Authorities during all the operational phases. In particular, the difference in temperature between the inlet and the outlet of the seawater needed for regasification system will be continuously monitored. Anyway, it was clarified that there are no problems in the change of temperature in the sea water used in the process of LNG heating to natural gas. Analysis were carried out from the inlet to the outlet point of water until it goes into the sea.