Composting at home has received a lot of attention in the media recently. There are many reasons why composting is great: it’s a natural process, a sustainable way to treat organic waste and we can do it at home at very low cost with significant benefits to our gardens and environment.
However, at a commercial scale, we are not so fond of composting. One of the main reasons is that composting generates odours that can cause nuisance. Some of the raw materials that it uses are odorous, such as food and animal wastes and the composting process itself can generate odours.
However, the environmental benefits of the composting outweigh its disadvantages. It is a natural process of treating organic material that diverts waste from landfill. Composting allows us to beneficially use materials that, in the past, were thrown away. Did you know that one important use of the garden waste collected from households is as a raw material for compost? Composting generates an important product that we use in our gardens and in farming, which significantly benefits our environment, quality of life and food.
While a composting facility will never smell like roses, neither does gardening or managing a farm when it comes to the use of manure and fertilisers. That being said, smell good composting is achievable for new facilities in three simple steps:
1) Site location and site layout: feasibility analysis
New composting facilities will benefit from being located amongst compatible land-uses that are insensitive to odours. Meteorological conditions play an important role in the odour dispersion and so, consideration needs to be given to the location and proximity of sensitive land-uses. An odour impact assessment would assist with the site layout and ensuring that odour controls are sufficient to avoid nuisance.
2) Avoiding anaerobic conditions
Compost piles need oxygen (aeration) to decompose the organic material with minimal odour. Frequently turning of piles prevents them from being compacted and becoming anaerobic, which generates the worst odours. In recent years, improved techniques have been developed to improve aeration, which increase composting rates and production volumes. Such techniques lead to reduced odour emissions per tonne of throughput compared with manual turning methods. Enhanced odour controls are also possible with positive aeration systems, which can result in further reductions in odour.
3) Managing the characteristics of the composting materials
A thorough evaluation of the products that will be used in the composting process will help minimise odour emissions and maximise the quality of the final compost product by balancing the carbon: nitrogen ratio, adequate pH, temperature on-site and moisture.
How can we help?
Katestone has had extensive experience in the assessment and management of odours associated with composting activities. Our high-quality odour impact assessments and odour management plans help clients ensure that nuisance odour and other potential impacts of composting are appropriately managed.
This article featured in the Katestone’s Clear Skies 2020 Spring edition. Click here to view other featured articles.