A closed culture system for the high density culturing of Artemia spp. in 300‐liter tanks using a new formula of artificial seawater and micronized waste products frm agricultural crops as food is described. Culture conditions are greatly improved by applying a new filter technique and an electronic transparency meter which controls food distribution automatically. A total volume of 6,000 liters of culture water is recirculated over a rotating biological contactor, a cross‐flow sieve and a plate separator at a flow rate of 3,000 liters per hour. Production yields obtained with this culture system, when extrapolated to a one m3 tank, indicate that 50 g of brine shrimp cysts can be converted into 20 kg of fresh (wet dry) pre‐adult Artemia in 14 days. These results are comparable to those reported earlier with open flawthrough conditions.

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Supercritical heat transfer has already been studied extensively, however, the majority of these studies focused on water or CO2. Data on refrigerants, which are used in for example transcritical or supercritical organic Rankine cycles or heat pumps, is scarce. Nonetheless, this data is crucial in order to size the heat exchangers used in these systems without significant overdimensioning. Therefore it is necessary to gain insight into the complex nature of supercritical heat transfer. For that purpose, experimental data on supercritical heat transfer to the refrigerant R125 is discussed in this work. Measurements were performed on a previously built test rig, where the refrigerant flowed in a horizontal tube with an inner diameter of 24.77 mm. Pressure, mass flux and heat flux were varied, and their influence on supercritical heat transfer was investigated. In general, heat transfer is enhanced for an increase in mass flux or decrease in heat flux, and no distinct effect of pressure on the heat transfer is measured.