“双碳”视角下基于LCA的市域秸秆资源化利用探讨

Exploring local straw resource utilization based on LCA from“double carbon”perspective

[目的]从“双碳”角度进一步推进市域秸秆资源化利用,明确各区域秸秆资源化利用全生命周期过程中的固碳减排能力。[方法]本文以山西省晋中市为例,基于《山西省统计年鉴》的相关数据,研究了2020年晋中市的作物秸秆资源量、全量化利用潜力及其空间分布特征,运用生命周期理论分析了各县(市、区)秸秆全量化利用的碳中和强度。[结果]2020年晋中市主要农作物秸秆可收集资源量为164.90万t,主要以玉米秸秆为主,占比84.66%,主要集中于晋中市中部及东北部地区。全市肥料化、饲料化、基料化、原料化、能源化利用潜力分别为71.41、39.00、3.77、1.00、49.72万t。单位秸秆原料化利用的固碳减排能力最高,为1.83 tCO_(2)eq·t^(-1),市域作物秸秆能源化利用碳中和强度最高,在0.2~0.7 tCO_(2)eq·hm^(-2)之间。[结论]寿阳县的作物秸秆可收集资源量最大,肥料化需求最高,应该重点推进秸秆的科学还田;祁县的牲畜饲养量大且饲料化碳中和强度最高,应该重点聚焦秸秆的饲料化利用方式,提高饲料化利用效率;东部地区由于其山地面积占比较大,不适宜作物种植,除了必要的秸秆还田外,应该重点推进秸秆的能源化、原料化利用。

[Objective]In order to further promote the utilization of straw resources from the perspective of"dual carbon"at the local level,this study aimed to clarify the carbon sequestration and emission reduction capacity during the entire lifecycle of straw resource utilization in different regions.[Methods]Based on relevant data from the“Statistical Yearbook of Shanxi Province”,the present study analyzed the quantity of crop straw resources,the potential for comprehensive utilization,and their spatial distribution characteristics in Jinzhong City in 2020.In addition,the life cycle theory was applied to analyze the carbon-neutrality intensity of comprehensive straw for each county.[Results]The results showed that the collectible quantity of main crop straw resources in Jinzhong City in 2020 was 1.649 million tons,primarily composed of corn straw,vegetables,millet,sorghum and others accounted for 84.66%,6.67%,3.04%,1.99%,and 3.64%of the total straw resources,respectively.The corn straw resources mainly concentrated in the central and northeast areas of the City.The potential for fertilizer utilization,feed utilization,raw material utilization,energy utilization,and material utilization were 714100,390000,37700,10000,and 497200 tons,respectively.The carbon sequestration and emission reduction capacity of straw raw material utilization per unit straw was the highest,at 1.83 t CO_(2)eq·t^(-1).The carbon neutrality intensity of crop straw energy utilization was the highest,ranging from 0.2 to 0.7 tCO_(2)eq·hm^(-2).[Conclusion]Shouyang County has the largest collectible crop straw resource quantity and the highest demand for fertilizer utilization,emphasizing the need for scientific straw incorporation into the field.Qi County had a large livestock population and the highest carbon neutrality intensity in feed utilization,suggesting a focus on straw utilization for animal feed to improve efficiency.Due to its large proportion of mountainous area unsuitable for crop cultivation in the eastern region,apart from necessary straw incorporation into the field,the emphasis should be on promoting energy and raw material utilization of straw.