a flexible tank ( 2 ) is placed inside a marine container or tank car ( 1 ) specifically on the floor of said container . the empty flexible bag is ideally laid on the entire floor of said container ( 1 ), care being taken that the floor of the marine ( container or of the tank car ( 1 ) is free of sharp edges or elements that might tear or damage the bag when expanding as a result of the solid and / or liquid content it will be filled with . at an initial stage , as shown in fig1 , the liquid that will form the liquid part of the solid - liquid content is injected . to this effect , an external supply , such as the regular supply line or an external tank ( 10 ), is used , from which the liquid is pumped , by means of a pump ( 9 ), or any other means of liquid supply , to the flexible tank ( 2 ); the liquid is injected through the top liquid - solid intake ( 3 ) that is located on the top side of the flexible tank or at the bottom intake ( 4 ). once the liquid content has been fully loaded , the external tank ( 19 ) and the pump ( 9 ) are disconnected , the filling of the flexible tank ( 2 ) being started , this process being able to be carried out together with the loading of solids into the flexible tank ( 2 ). to this effect , as is shown in fig2 , a feeding pipe ( 13 ), as well as top intake of the flexible tank ( 3 ) is introduced through the funnel ( 12 ) or via any system as required to load the specific product , as shown in fig2 , or through the bottom intake of the flexible tank ( 3 ) or through the bottom intake ( 4 ) the solid material ( 14 ), together with the liquid ( 15 ) that is removed by way of a pump or any other system , from a bottom outlet ( 4 ) located in the flexible tank , and is transported through a transportation pipe ( 16 ) to said funnel ( 12 , silo or another suitable system for the product that is being loaded ). once the optimum filling level in the flexible tank ( 2 ) has been reached , all of the elements outside the container or tank car ( 1 ) and connected to the flexible tank ( 2 ) are removed , all of the intakes and outlets previously used being closed , thus the container or tank car ( 1 ) being ready to be transported as shown in fig3 . once the container has reached its destination , it is unloaded as shown in fig4 . to this effect , liquid is retrieved from a target tank ( 11 ) wherein the solid - liquid content retrieved from the flexible bag ( 2 ) will be stored by setting up a pump ( 8 ) or the system that has been included for the specific product from the bottom outlet of the target tank ( 11 ) and will be injected into the top intake ( 3 ) by way of a hose ( 18 ) to assist the transportation of solids contained inside the flexible tank ( 2 ), the solid - liquid content of the flexible tank ( 2 ) exist through the bottom outlet ( 5 ) until its content is fully discharged into the target tank ( 11 ), which may also be another vessel where said content remains available for processing . finally , the flexible tank ( 2 ) is removed empty from the interior of the container or tank car ( 1 ) being broken to remove any remains of the content that may have remained inside it . then , the flexible tank ( 2 ) is disposed of . this system may have a heating system allowing to heat the liquid medium ( that solidifies or otherwise ) to facilitate the protecting medium ( preserver ) to flow together with the product that must be transported and protected .