Agricultural Systems ( IF 6.6 ) Pub Date : 2021-02-18 , DOI: 10.1016/j.agsy.2021.103100 Göte O.B. Bertilsson , Holger Kirchmann
CONTEXT
A concept was presented to produce N fertilizer by digesting straw in a biogas plant and transporting bio-methane to a fertilizer plant through a gas grid substituting natural gas.
OBJECTIVE
The rational was to find out if straw, a residue not infringing on food production and not needing extra cropland, converted to methane in a biogas reactor, is a viable option for ammonia synthesis.
METHODS
Scenarios calculations were based on straw from 1 ha wheat producing 7 Mg of grain using 150 kg of fertilizer N. Removal rates of straw were 60 or 100%. Digestion residues were returned to fields within a radius of 50 km. Three scenarios with varying straw removal and low to high efficiency of the biogas and fertilizer plant were assessed.
RESULTS AND CONCLUSIONS
A sensitivity analysis showed the combination of a medium to high efficient biogas and fertilizer plant using between 3.5 and 7 Mg straw covered the energy need for crop management, transportation of straw and digestate and N fertilizer production and still delivered a surplus of 838–9192 kWha ha−1. The amount of 1 Mg of straw enabled the production of 94 to 173 kg fertilizer N.
SIGNIFICANCE
Use of straw can be a useful alternative for N fertilizer production making agriculture more sustainable.
中文翻译:
基于循环的可持续氮肥生产:秸秆-沼气-“ Haber-Bosch”工艺
语境
提出了一种通过在沼气厂消化秸秆并通过替代天然气的气网将生物甲烷运输到化肥厂来生产氮肥的概念。
客观的
合理的方法是找出秸秆(一种不影响食品生产且不需要额外耕地的残渣)在沼气反应器中转化为甲烷,是否可用于合成氨。
方法
方案的计算是基于使用150 kg肥料N的1公顷小麦生产7 Mg谷物的秸秆。秸秆的去除率为60%或100%。消化残余物返回到半径50公里以内的田地。评估了三种情况,其中包括不同的秸秆去除率以及沼气和化肥厂效率从低到高。
结果与结论
敏感性分析显示,使用3.5到7 Mg秸秆的中到高效沼气和化肥厂的组合满足了作物管理,秸秆和消化液运输以及氮肥生产的能源需求,仍然提供了838–9192 kWha的过剩ha -1。1 Mg的秸秆可以生产94至173 kg的氮肥。
意义
秸秆的使用可以作为氮肥生产的有用替代方法,从而使农业更具可持续性。