LuGaZ’s three pillars sustainability

Traditional management of cow manure in many agriculture-based regions of Europe is based on temporary storage and direction land application as a fertilizer. This procedure is still valuable but presents a challenging environment concern in those cases where the farm does not dispose of land enough to securely apply the manure. This problem can be mitigated by treating this excess of cow manure through a decentralized AD process that allows, moreover, to recover all the energy potential of this fraction. Besides, management of agri-food biowaste of different nature is challenging from the sanitary (e.g. in the case of slaughterhouse waste), environmental and economic points of view (costs accounting sometimes for transport and centralized energy intensive treatment). However, these organic feedstocks contain high energy potential but are often disregarded as resource. It is possible to mix these with cow manure and other organic liquid substrates (dairy sludge) to unleash significant energy potential. 

Current knowledge on the environmental impacts regarding LuGaZ plant will be completed in exhaustive Life Cycle Assessment (LCA) studies. At first glance, it has been identified two main concerns. On the one hand, digestate application, considering both soil fertility and nitrogen release into atmosphere and groundwater. In this sense AGROAMB has performed several LCA and the solid waste will go to their facilities with proved benefits in terms of agricultural yields. On the other hand, biogas upgrading to biomethane due to the methane slip in the off gas that can significantly reduce the environmental benefits. This will be considered in risk assessment and reduced to minimize the possible impacts. But beyond the impacts, some advantages of the proposal deserve to be outlined from different perspectives as explained below.

Environmental pillar

• Significant reduction of GHG emissions mainly due to reduction of methane fugitive emissions during uncontrolled decomposition of cow manure in absence of management strategy. 
• Significant reduction of odour potential of organic biowastes, since main responsible bad odour compounds (low chain fatty acids: butyric, propionic acid) will be degraded in the first steps of AD. 
• Limitation of carbon footprint linked to the long-distance transport of residue (in alternative centralized treatment plants). 
• Biogas and biomethane production will replace fossil gas natural use in an equivalent amount.  
• Water Recovery from waste: enabling its utilization as process or irrigation water close to the plant. 
• Resource recovery (N, P, K) into fertiliser, replacing high carbon-intensity of the traditional fertilizer production.
• Eutrophication risk of land and aquifer is reduced treating the LuGaZ residues and manure. 
• Selection of low-impact technologies to surround the core AD process, such as the depuration and upgrading aligned with the project call and consortium purposes and policies. 
• AD treatment will reduce the lixiviates and the potential eutrophication of aquifers (nitrates issues). 

Economical pillar

• Reduction of energy dependence on fossil fuels from other countries also increasing security of supply. 
• Reduction of treatment cost of biowaste management (industrial or municipal organic fraction). 
• Production and sale of generated biomethane (and other potential by products: bioCO2 and fertiliser, as well as production of water for reuse). 

Social pillar

• Primary sector dynamization, helping to fix population and creating employment in rural or dispersed areas where the raw material to produce biomethane is generated, mainly from agricultural and livestock waste.
• Proactive participation in developing of strong regional model entirely based on Circular Economy principles. 
• Regional accessory industry development (boiler, machinery, etc.).