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Industrial Composting Technologies: An Introduction

At Compost Magazine, a lot of our focus is on home composting. But what if you want to create more compost – a lot more compost? 

Industrial composting could be your answer.

Industrial composting technologies allow you to turn organic waste into compost on a much larger scale than you could ever achieve with a home composting system. To achieve this scale, specialised equipment and facilities are often used.

There are several different methods and technologies that can be used for industrial composting, including aerobic composting, vermicomposting, and in-vessel composting. Here you find a brief introduction to each one. At the end of this article, you’ll find an extensive list of resources to help you learn more. 

Types of industrial composting technologies

Long lines of covered windrows.

Static Pile Composting (SPC)

Static Pile Composting simply involves creating large piles of organic material. Despite the name, these may be turned from time to time, often with heavy machinery such as tractors. The piles are often covered with fabric or material to minimise heat and moisture loss. 

The method can be a great way to get started. It doesn’t require the same investment in equipment as some of the other methods listed here, but can be switched relatively easily to an aerated system. 


  • Low start-up costs
  • Good moisture retention
  • Relatively simple to maintain
  • Reduced maintenance
  • Reduced investment in equipment


  • Composting may not take place as evenly as some other methods
  • May not reach temperatures needed to break down some materials

Malcolm Beck (aka The Compost King) was a great proponent of simple static piles for getting started. In How To Produce Compost on a Large Scale he explains the benefits of SPC – and some of the perils of getting advanced equipment too quickly.

Static Aerated Pile Composting (SAPC)

Static aerated pile composting uses a compost aerator to force air through piles of organic material. 

The air provides substantial oxygen to microorganisms in the organic material, resulting in higher temperatures, faster decomposition, and more efficient use of composting space compared to traditional composting methods. 

However, it’s worth noting that one study by Ruggieri et al found that the benefits of aerated composting were minimal if regular turning is already taking place. 


  • can handle a wide variety of materials
  • can be used to compost materials that are not well-suited to other methods, such as biosolids, municipal waste, and food waste
  • efficient use of space
  • temperature can be controlled and monitored, resulting in better pathogen reduction


  • can be energy intensive
  • requires regular turning to ensure aeration and even composting
  • requires more management and monitoring than some other methods
  • smells can be an issue if not managed properly

Learn more: Steve Churchill of the Urban Worm company has an excellent introduction to SAPC, and also chronicles his steps setting up a small-scale system of his own.

In-Vessel Composting

In-vessel composting separates the waste from the environment using enclosed containers or vessels. These vessels can take a number of different forms, including containers, silos and drums. The compost is often aerated or agitated during the process. 

As with tunnel composting, this method allows for higher temperatures and greater control over the composting process, leading to faster decomposition. The system involves heavy initial investment, but the capacity is high, especially as typically the vessel is only used for the first stage of composting, after which it is usually removed and placed in a windrow or static pile. 


  • High processing capacity
  • Controlled environment
  • Odour is rarely a problem
  • Reduced risk from pests and pathogens.
  • Flexibility: Can be used to compost a wide range of organic materials, including food waste, yard waste, and manure.


  • High upfront costs 
  • Depending on the method used, it can be harder to physically check the compost
  • Depending on the system used can be expensive to set up.
  • Limited space for composting.

See The Compost Handbook (Chapter 7) for an in-depth discussion of in-vessel composting. 

Tunnel Composting

As the name suggests, tunnel composting usually involves a long narrow structure to enclose and contain the organic material used to make the compost. (Tunnel composting is also sometimes classified as in-vessel composting.)

While other systems often take place outside, tunnel composting provides a controlled environment for the composting materials, allowing for precise temperature, moisture, humidity, oxygen levels and ventilation levels to be maintained.


  • High processing capacity
  • Easy to expand: Tunnels often have a modular design, which makes it easy to increase the size of a facility. 
  • Reduced odours: The enclosed nature also minimises the risk of bad smells, which can be particularly helpful when your facility is close to houses. 
  • Reduced pathogen risk: The enclosed nature of the tunnel can reduce contamination from pests and other sources. 


  • High upfront costs: The construction and installation of a tunnel composting system can be expensive, especially when compared to other methods of composting.
  • Energy use: Some tunnel composting systems rely on mechanical ventilation and temperature control systems, which can be energy-intensive.
  • Limited space for composting: Tunnel composting systems require a dedicated space for the tunnel, which can be a limiting factor in some locations.
  • Limited versatility: Tunnel composting systems are designed specifically for the composting process, and may not be suitable for other types of organic waste management activities.

Windrow Composting

From inside to outside again! In Windrow composting organic material is placed in long rows, and is often turned regularly. This ensures air saturates the compost, providing oxygen to bacteria which then rapidly break down the material. The turning is often done manually, but the process can also be automated.  


  • Low upfront costs: Windrow composting systems are relatively simple and inexpensive to set up, especially when compared to more complex systems like in-vessel composting or anaerobic digestion.
  • Versatility: These systems can be used to compost a wide range of organic materials, including food waste, yard waste, and manure.
  • Flexibility: Windrow systems can be scaled up or down to meet the needs of a particular operation.


  • Smaller windows can be prone to drying out. 
  • Weather dependent: As Windrow composting usually takes place outside, it is vulnerable to the effects of weather, such as wind and rain, which can impact the decomposition process.
  • Potential for smells if not properly managed.
  • Potential pathogen problems: As the composting process takes place outside, some sources argue is an increased risk of contamination from sources such as rodents, groundwater and wind. However, a good composting process will eliminate most pathogens.
  • In some countries, there are legal restrictions on the materials that are allowed to be composted with this method. 
  • Can require large amounts of land.

Vermicomposting (worm composting)

You might imagine that worms can only be used for small-scale composting – but vermicomposting can take place at scale, breaking down tonnes of organic material. 

It’s a fascinating process in which worms consume compost material, digest them and excrete castings. They do greatly reduce the amount of material in the process. However, the castings produced make superb compost. In fact, one group of researchers described worm castings as a “peat like material with excellent structure, porosity, aeration, drainage and moisture­ holding capacity.”

Worm composting often takes place in specialised containers. These are available in a variety of sizes which can deal with anything from several tens of kilos to tonnes. 


  • Low upfront costs: Vermicomposting systems are relatively simple and inexpensive to set up, especially when compared to more complex systems like in-vessel composting or anaerobic digestion.
  • Odour control: Vermicomposting systems generate minimal smell.
  • High-quality compost: Vermicompost is often considered to be of higher quality than other types of compost.
  • Low energy requirements.
  • Worms may reduce the number of pathogens in compost. 


  • Capacity: Vermicomposting systems are generally not suitable for handling huge volumes of organic waste.
  • Limited versatility: Vermicomposting systems are generally not suitable for composting materials that are highly acidic or toxic.
  • Specialised care: Vermicomposting systems require specialized care, including maintaining the proper temperature, moisture, and feeding regimes for the worms.

Also see: The Benefits of Worms In Compost

Anaerobic Digestion

Many of the systems we have looked at so far use oxygen to encourage bacteria to rapidly break down compost materials. 

Anaerobic digestion still uses bacteria (albeit different types) to break down organic materials – but does it in a low oxygen or oxygen-free environment. (Do note that some composters will argue that Anaerobic Digestion is not composting.)

This method produces two valuable byproducts.

The first is biogas which can be used to generate electricity. In some countries, this can be fed into power systems in return for a feed-in tariff. The second is a digestate which can be used as a fertiliser. 


  • High processing capacity
  • Potential for energy production: The biogas produced by anaerobic digestion systems can be captured and used as a renewable energy source.
  • Nutrient recovery: The digestate produced by anaerobic digestion systems is rich in nutrients, which can be used as a soil amendment or fertiliser.
  • Reduced odours: Due to the lack of oxygen, odor is not usually a problem.


  • High upfront costs
  • Energy use. This depends on the system used: some anaerobic digestion systems rely on mechanical agitation and temperature control systems, which can be energy-intensive.
  • Limited versatility: Anaerobic digestion systems are generally not suitable for composting materials that are highly acidic or toxic.
  • Complex operation: Anaerobic digestion systems require careful management and monitoring to ensure optimal performance.
  • Potentially more harmful to the environment than aerobic composting.

Learn more: The US EPA has an extensive guide to Anaerobic Digestion.

Treating composting as a business

Two hands hold compost against a backdrop of a sunset.

So far this article has really just scratched the surface! There’s a host of other industrial composting methods used, from using chickens to scratch and turn compost to using the highly efficient Rocket Composter. 

However, if you’re looking at setting up your own facility it’s important to do your research before selecting a system. After all, the vast majority of composting facilities fail. In a recent podcast, Carla Castagnero of AgRecycle argued this is because many new commercial composters fail to treat composting as a business.

Reading articles like this is only a first step – I’d suggest talking to other people who have been through the same journey as you, finding out what worked and what didn’t work. The resources below, which were put together with the help of Joe Hoffman of Compost Business, are a good place to help.



BioCycle | The Organics Recycling Authority
Compost Training Videos – Green Mountain Technologies (
Composting – Institute for Local Self-Reliance (
Composting – Institute for Local Self-Reliance (
Composting – Cornell Waste Management Institute
Compost University
Compost Business


The Composter Podcast
The Community Composting Podcast


US Composting Council
UK Gov guidance on Waste and Environmental Permits


The Composting Handbook

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