Environmental Officer, Department of Environment and Sustainability, A Coruña City Council, 15011 A Coruña, Spain.
Composting Department, Organic Wastes Management Consultancy, 08027 Barcelona, Spain.
Int J Environ Res Public Health. 2020 May 1;17(9):3153. doi: 10.3390/ijerph17093153.
The amount of biowaste generated by university canteens (BWUC) in the faculties of the University of A Coruña (UDC) varies between 6 and 100 kg/day. In addition, the gardening services of the campus generate even higher amounts of garden waste (GrW), including pruning, which, once crushed, serves as bulking material for composting the biowaste from the canteens. Decentralized composting has been chosen with the aim of producing high quality organic fertilizers for university urban gardens while reducing the environmental burdens of both waste management and agricultural practice. Small static home composters of 340 L (SHC) for smaller amounts of generation (up to 20 kg BWUC/day) were used, while, for faculties of higher generation (up to 40 kg BWUC/day on average), the first composting stage was carried out in a closed and dynamic composter (DC). The dynamic composter was designed and built specifically for this project and its features were improved and optimized throughout the study. The pilot project was carried out in two centers of the UDC, which are known as the Philology Faculty (PF) and the School of Architecture (SA). All the organic waste generated by the canteens of these two colleges from January 2011 to July 2011 (approximately 3000 kg) was treated. Composting in SHC included a thermophilic phase that extended one month beyond the loading period for which thermophilic temperatures were also recorded. The use of the DC as the first stage in combination with static composters (SC) for the maturation stage reduced the overall thermophilic phase to 6-8 weeks. The complete maturation ( class IV-V) was achieved after about four months in SHC and after two months when using the combined DC-SC system, if the right conditions of moisture were maintained. The chemical quality of the compost produced was compatible with Class A of Spanish legislation (equivalent to organic farmer quality) and the C/N ratio ranged from 9 to 15 depending on the relation BWUC:GrW.
大学校园餐厅（BWUC）产生的生物废物量在阿科鲁尼亚大学（UDC）各院系之间变化在 6 到 100 公斤/天之间。此外，校园的园艺服务还会产生更高数量的园林废物（GrW），包括修剪，一旦粉碎，就可作为堆肥的膨胀材料，用于堆肥餐厅的生物废物。选择分散式堆肥是为了生产高质量的有机肥料，用于大学城市花园，同时减少废物管理和农业实践的环境负担。使用了小型静态家用堆肥器（SHC），用于处理较小量的生物废物（每天最高 20 公斤 BWUC），而对于产生量较高的院系（每天平均高达 40 公斤 BWUC），第一阶段的堆肥是在封闭和动态堆肥器（DC）中进行的。该动态堆肥器是专门为这个项目设计和建造的，在整个研究过程中对其进行了改进和优化。该试点项目在 UDC 的两个中心进行，这两个中心分别是语言学系（PF）和建筑学院（SA）。这两个学院的餐厅从 2011 年 1 月到 7 月产生的所有有机废物（约 3000 公斤）都得到了处理。SHC 中的堆肥包括一个高温阶段，延长了一个月，超出了高温温度记录的加载时间。将 DC 用作第一阶段，与静态堆肥器（SC）结合用于成熟阶段，将整个高温阶段缩短到 6-8 周。在 SHC 中，大约四个月后达到完全成熟（IV-V 级），而在使用 DC-SC 组合系统时，两个月后达到完全成熟，如果保持适当的水分条件。所生产的堆肥的化学质量符合西班牙法规 A 级（相当于有机农民质量），C/N 比根据 BWUC:GrW 的关系在 9 到 15 之间变化。
