Energy Potential of Agri Residual Biomass in Southeast Asia with the Focus on Vietnam
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Value Rice, paddy 44,046,250 Sugarcane 17,945,204 Vegetables, fresh 14,879,631 Cassava 9,847,074 Maize 4,874,054 Fruit, fresh 2,835,078 Source: Data from [ 6 ]. Based on Table 1 , considering the vast production, which is also significantly associ- ated with the generation of residual biomass, paddy rice and sugarcane were chosen as the main concern of this study. As one of the most important cereals in Vietnam [ 7 ], rice farms have developed rapidly in recent decades. Between 1994 and 2017, rice production more than doubled [ 5 ], from 20 billion tons to more than 44 billion tons. The rice yield increased from 2.9 t ha −1 in 1990 to 5.8 t ha −1 in 2018, while the area of paddy rice plantations enlarged by only about 1.1% per year [ 5 , 8 ]. In the preceding decades, rice was collected manually, and the leftover biomass was suitable as a raw material for the paper industry, fertilizers and animal fodder. Nowadays, residue management in Vietnam has changed. Paddy rice on extensive commercial fields is collected by the new combine-based harvesting method, and the vast and increasing proportion of rice residues is left unused or commonly burned directly on the fields [ 7 , 9 , 10 ] with a negative environmental impact on the surroundings [ 7 ]. In the case of sugarcane, after the rapid increase of sugarcane production in Vietnam in the 1990s (see Figure 1 ), sugarcane production has practically not changed in the last two decades, varying from 14 to 20 million tons per year, with the highest production during 2013–2014. In 2018, almost 18 million tons of sugarcane were produced [ 11 ]. According to the Ministry of Agriculture and Rural Development of Vietnam [ 12 ], the trend is to continue stable production on up to 300,000 ha with increasing sugar output and quality. Sugarcane yields are high, about 70 t ha −1 (compared to about 1 t ha −1 for wheat, 2 t ha −1 for other grasses and 20 t ha −1 for trees) [ 13 ]. Agronomy 2021, 11, x FOR PEER REVIEW 2 of 20 The agricultural sector accounts for more than 15% of Vietnam’s gross domestic product and concurrently for 40% of the country’s labor force [5]. Table 1 shows the dom‐ inant crops that are cultivated in the country. tải về 1.15 Mb. Chia sẻ với bạn bè của bạn:
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