Composting dairy slurry

泥浆和粪肥是宝贵的农场资源，但它们的养分不稳定，会造成排放和污染，包括硝酸盐浸出。该提案将评估将奶牛农场粪便堆肥的潜力，将污水分开处理，从而在农业系统中建立循环。农场的碳源将用于堆肥，稳定养分，生产更平衡、更有益的肥料。该项目将测试不同形式的堆肥，监测堆肥、浆液和脏水的营养成分，并测量与浆液相比，在堆肥、储存和传播过程中产生的排放。最终，产出将用于评估以农场为基础的湿地生态系统处理（WET）系统处理污水的潜力。首先，从刮下来的院子里的粪便将从浆液系统中取出，并与碳源（农场的粪便，从经过授粉的柳树中取出的木屑，和覆盖的树篱）结合，以产生堆肥基质。我们假设这个过程将以生物形式稳定营养物质，可以用作土壤改良剂，与泥浆相比，硝酸盐浸出和流失的风险更低。该项目将评估堆肥粪便的不同方法，并测量营养成分随时间的变化。两种主要的堆肥系统将进行试验；博卡什和传统的转制。我们的目标是了解堆肥的最佳比例和成分类型，使负面影响最小，并为土壤健康和肥力提供最佳营养概况。这将通过皇家农业大学的农场现场实验和实验室分析进行，同时进行文献综述，以了解当前的做法及其对该系统的适用性。项目的第二部分将在第一年开始，但将在项目结束后继续进行，并将在除去固体粪便后调查粪便中液体部分的使用情况。其目的是在堆肥过程中利用液体中的所有/大部分营养物质。然后，剩余的脏水将通过包含柳树的清洁湿地系统，这些柳树将在堆肥过程中使用。需要进行调查，以了解如何在湿地系统中处理这种液体部分，因为在目前的监管框架下，任何与粪肥接触的液体都被视为泥浆，受环境监管。

Slurry and manures are valuable farm resources, but their nutrients are labile, causing emissions and pollution, including nitrate leaching. This proposal will assess the potential for composting dairy farm manure, treating dirty water separately and thereby building circularity into the farming system. Carbon sources from the farm will be used to compost manure, stabilising the nutrients and producing a more balanced and beneficial fertiliser. The project will test different forms of composting, monitor the nutrient profiles of the composts, slurry and dirty water, as well as measure the emissions produced during composting, storage and spreading, compared to slurry. Ultimately, the outputs will be used to assess the potential for treating dirty water with a farm-based Wetland Ecosystem Treatment (WET) system.Firstly, manure from scraped yards will be taken away from the slurry system and combined with carbon sources (farmyard manure, woodchip from pollarded willows, and coppiced hedges) to produce a composted substrate. We hypothesise that this process will stabilize nutrients in a biological form that can be used as a soil improver, with lower risk of nitrate leaching and run off, compared to slurry. The project will assess different ways of composting the manure and measure the nutrient profile changes over time. Two main composting systems will be trialed; Bokashi and a traditional turned system. We aim to understand the optimal ratio and type of ingredients for composting with minimal negative effects and optimal nutrient profiles for soil health and fertility. This will be conducted via field experiments on farm and laboratory analysis at the Royal Agricultural University, alongside a literature review to understand current practices and their applicability to this system.The second part of the project will start in the first year but continue beyond the duration of the project, and will investigate use of the liquid fraction from manure when the solid manure has been removed. The aim is to take all/most of the nutrients from this liquid for use in the composting process. The remaining dirty water will then run through a cleansing wetland system incorporating willows that would be coppiced for use in the composting process. Investigation is needed to see how this liquid fraction can be treated in a wetland system as under the current regulatory frame work any liquid that has been in contact with manure is considered subject to environmental regulation as slurry.