Onion is a commonly used vegetable in the Cuyo Region, Argentina, and important in the world global vegetable production ranking. Production levels often exceed immediate markets of fresh sale, and excesses, although still edible, are currently discarded (mostly incinerated and disposed in landfill, creating numerous environmental hazards). To minimize these adverse environmental problems, this research investigates upgrading the discarded products by dehydration, hence guaranteeing their ultimate food-use. The dehydration process of discarded onion cv. Crioula Roxa was hence studied at 60 and 70 °C, temperatures selected to maintain the main physicochemical characteristics of the onions, while also creating optimum heat and mass transfer coefficients while significantly reducing the energy consumption and CO₂ emissions.

When using an electrically-heated convective dryer, the Specific Energy Consumption (SEC) values and the CO₂ emissions during dehydration at 70 °C are 738.89 kWh.kg⁻¹ and 264.74 kg of CO₂ kg⁻¹, respectively. These values are only 41.61 kWh.kg⁻¹ and 2–4 kg of CO₂ kg⁻¹ if a solar dryer is applied. The thermal diffusivities were 1.86✕10⁻¹⁰ m² s⁻¹ (dehydration) and 1.08✕10⁻¹⁰ m² s⁻¹ (rehydration), showing a weak effect of the dehydration process on the solid structure and properties.

洋葱是阿根廷库约地区的常用蔬菜，在全球全球蔬菜产量排名中很重要。生产水平通常超过新鲜销售的直接市场，并且多余的（尽管仍然可以食用）目前被丢弃（大部分被焚化并丢弃在垃圾填埋场中，造成许多环境危害）。为了最大程度地减少这些不利的环境问题，本研究研究了通过脱水来升级废弃产品的方法，从而保证了最终食品的使用。洋葱cv的脱水过程。因此，在60和70°C下研究了Crioula Roxa，选择该温度以保持洋葱的主要理化特性，同时还创建了最佳的传热和传质系数，同时显着降低了能耗和CO₂排放。

当使用电热对流干燥器时，在70°C脱水时的比能耗（SEC）值和CO ₂排放分别为738.89 kWh.kg ^-1和264.74 kg CO ₂ kg ^-1。如果使用太阳能干燥器，这些值仅为41.61 kWh.kg ^-1和2–4 kg的CO ₂ kg ^-1。热扩散率为1.86× ^{10 -10}  m ²  s ^-1（脱水）和1.08× ^{10 -10}  m ²  s ^-1（脱水），显示脱水过程对固体结构和性质的影响较弱。