Paper No 027 – Pervaporation Membrane for Refrigerator Vegetable Tray Applications – 13th IEA Heat Pump Conference, Jeju, Korea
Many vegetables produce moisture and need moisture for preservation. Higher relative humidity in the vegetable trays or crisper drawers helps to keep vegetables sturdy and fresh. However, cold surfaces can result in condensation and the presence of liquid water inside the unit. One disadvantage of using heat pumps in refrigerators, it the propensity to develop condensation inside vegetable trays. Approximately 1.3 billion tonnes of food is wasted per year around the world [1], leading to excess energy requirements and greenhouse gas emissions. It is important to control all aspects of spoilage, including food storage during refrigeration. One method to increase the storage time of vegetables is to control moisture inside these trays and reduce dehydration, while preventing condensation, or pooling of water. In this paper we describe a pervaporation method, utilizing advanced composite ionic membranes, to control the humidity levels of a sealed box. The system involves an ultra-thin, ultra-strong, ultra-high-water permeability ionic membrane, with a circulation system for enhanced pervaporation. The system improvements allow for a sealed box, Air Exchange Rate (AER)