APPLICATION OF ABSORPTION HEAT TRANSFORMERS FOR ENERGY-CONSERVATION IN THE OLEOCHEMICAL INDUSTRY

A comprehensive energy mapping of an oleochemical plant, for productio n of technical fatty acids and refined glycerol, was performed. Satura ted water vapour is currently produced at 100-degrees-C from four flas h vessels used to depressurize condensate streams emerging from differ ent processing units in the plant. This vapour has a heat content of 3 14 kW and is currently condensed in a dump condenser and discharged. I ncorporating an absorption heat transformer system would enable the re covery of almost half of this energy and a temperature lift of 34-degr ees-C can be achieved. The heat transformer system delivers steam at 3 bar which can be fully reused in the plant. An economic analysis resu lted in a pay-off period of less than 18 months based on a steam cost of 14.25 $/GJ, an installed equipment cost of 535 $/kW, an annual oper ation time of 7200 h, and a heat transformer efficiency of 0.45. Howev er, the pay-off period depends on the estimated steam cost and heat tr ansformer efficiency, and also on how much of the existing equipment c an be utilized as components in the heat transformer. Installing the h eat transformer would require minimum changes in the existing plant.