**4. Economic evaluation**

The evaluation of the economic feasibility of the process of obtaining of the microalgas *D. salina* was carried out on the base of the experience gathered until that moment with the one made for the Chlorella sp. [12, 13], and keeping in mind the pilot plant capacity installed at "Industrial de alimentos" (INDAL).

In this calculations was considerate:

*a—a volume of cultivation of 3 m3 .*

*b—a yield of 0.8 kg of dry alga for m3 of culture medium.*

*c—a productivity of humid alga that represents a biomass from 1.6 to 2.1 kg/day.*

*d—a retention time of 15–20 days for each harvesting, representing a crop cycle every two weeks.*

*e—an available time of 300 days troops, foreseeing 60 days of bottom of technological requirement and other causes.*

The methodology for these calculations were carries out using the pattern of economic evaluation created by the ABL of the University of Murdoch, Western Australia, being calculated the cost of a kg of alga for the pilot plant installed at INDAL industry, as well as for an industrial plant. In the **Table 2** a summarized information of the calculation about the unitary cost is presented. The cost obtained to produce 1 kg of alga, as it has been calculated with the pattern in question it was among \$6.4 and \$4.0 USD.
