Environmental footprint study of white rice production chain-case study: Northern of Iran

Abstract

Rice is globally counted as a highly important food. Among its production processes, paddy production, drying and whitening are energy-intensive that leave environmental impact. The study analyzes the environmental parameters (by SimaPro 8.1) for the growth of two rice paddy varieties (low-yield and high-yield) in three Northern provinces of Iran (Mazandaran, Guilan and Golestan) using two mechanized and traditional planting methods. The environmental impact of white rice production in milling plants and its drying using two dryers (modern and conventional) running on three different fuels (kerosene, diesel fuel and natural gas) was analyzed. Finally, the husking and whitening processes through three different systems (conventional, semi-modern and modern) were investigated. Results revealed that the highest environmental impact occurred when using the mechanized planting system to grow the low-yield variety in Mazandaran province (MC-LYV-MP). The lowest impact was observed in Guilan province when growing the high-yield variety using the traditional practice (TC-HYV-GiP). During the drying process, the largest adverse environmental effects (mechanized harvesting, high-yield variety, and conventional drying) were found to be 1.92 times higher than their lowest level (traditional harvesting, low yield variety and conventional dryer) using kerosene and 4.73, and 5.59 times higher than their lowest level (traditional harvesting, low yield variety, and modern drying) using diesel fuel, and natural gas, respectively. The processing (husking and whitening) results also suggested that the use of modern systems exacerbated the environmental impact by 1.42 (low-yield variety) and 1.53 (high-yield variety) compared to the traditional paddy processing methods.

Keywords: Drying; Life cycle assessment; Paddy; Processing.