6 Best Practices
Collection of Food Scraps
One of the most important factors in whether an On site Composting system will succeed or fail is the manner in which food scraps are collected. If there is any “ick factor” for those not directly involved with the Composting process there will be less and less support for the effort.
Any collection method should be:
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- Easy
- Clean
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Every collection method will be unique to your specific work site. The following tips will help to set up a collection system that is easy and clean.
To keep things Easy – Set up collection containers next to where the food scraps are being made:
- Kitchens
- Next to prep areas
- Next to existing waste bins
- Large enough to handle one meals worth of scraps, so it is convenient without the need to swap containers before meal prep is complete.
- Coffee Rooms
- Next to coffee machine
- Next to existing waste bins
- Easy to use and understand instructions on what can go in the collection container.
To keep things Clean –
- For both Kitchens and Coffee Rooms
- Utilize container liners. These can be compostable liners that will be composted with the food scraps, or plastic liners that will need to be removed before Composting. (Note: there are Certified Plastic Compostable liners, look for a home compostable label or BPI Compostable Certification)
- Or, Clean containers between collection
- Use a container with a lid, so that it can covered when not being used
- Collect regularly
- Create a plan to empty collection containers in the kitchen or coffee room daily.
- Utilize a larger collection container outside or away from eating areas to collect the food scraps if they need to be kept longer before they can be placed in the Composting System.
- Set up your Composting system to process these scraps on a weekly to biweekly basis.
- If fruit flies become an issue, increase collection frequency to avoid food waste sitting and allowing populations to flourish.
Any collection system will require people to utilize it. Ensure that training and signage is provided to staff on what they can place in the organics or food scraps collection bin.
Monitoring Key Parameters:
- Moisture Level
- Check the moisture level of the Composting system using your hands.
- Use the hand squeeze test to measure moisture.
- Maintain good moisture level
- If too dry – Add water, evenly water material with a spray bottle, or spray nozzle on hose.
- If too wet – Add additional dry brown material to soak up moisture and provide air space for air to move through and dry the material. (Paper or cardboard, sawdust etc…)
- Temperature
- Use a temperature probe to measure the temperature at the center of the Composting material. For systems that have a smaller volume a typical meat thermometer will suffice. However in a larger windrow system a specially made Compost temperature probe that is long enough to reach the center of a pile is required.
- Smell
- Use your nose to assess whether there are any unpleasant odours.
- Worm health (In Vermicomposting systems)
- In Vermicomposting systems, it is important to monitor worm health.This is covered under the Vermicomposting section of the System Set up Guidance.
Trouble Shooting
With monitoring and observation of the Composting system any problems should be caught quickly and can be fixed quite quickly. Remember the Composting basics of Browns, Greens, Water and Air and you should be able to fix any composting issue.
Common Composting Problems
- Smells sour or manure like – this typically means that the Composting process has gone anaerobic. Observe your composting material to determine whether it is too wet, or whether it needs to be mixed to incorporate more air into the system.
- Not Composting quickly enough – this is typically one of two things. Either the Browns to Greens (Carbon to Nitrogen) ratio is out of balance and needs to be adjusted, by adding more brown or green material whichever is lacking. (As a starting point in most systems you’ll need twice the amount of brown material by volume then green material) Or it is too dry and the biological process has slowed down or come to a stop.
- Pests are attracted to feed stocks or Composting process – determine what pests are attracted to and either remove them from the Composting process or ensure that they are covered throughout the Composting process and are not exposed where pests may find them.
- Excessive flies – this is a sign that the Compost process has gone anaerobic as Flies are attracted to anaerobic decomposition. Mix or turn the Compost to incorporate more air so that flies are not as likely to be attracted to the compost.
- Fruit Flies – If raw vegetable matter is exposed to air, it will attract fruit flies. Ensure that vegetable material is covered by “brown” materials so as not to be an attractant. For continuous feeding systems like some In-vessel systems, or Vermicomposting systems ensure that material added will be broken down within 3 to 5 days. Also, fruit flies do not hurt the Composting process and are only a nuisance to the humans dealing with the Composting system. If you don’t mind a few fruit flies keep a fruit fly trap close to the Composting system or stick fly paper to the top of the worm bins in order to minimize their numbers.
- Too Wet – If the material is too wet, (when squeezed, water pours out from between your fingers) it will quickly lead to anaerobic issues which can become a smelly problem, slow down the Composting process and even kill off beneficial organisms that aid in the Composting process. The material should be mixed with dry material or mixed regularly to dry out the material.
- Too Dry – if the material is too dry it will not form a ball in your hand when squeezed and the composting process will slow down significantly. Water can be added when the material is too dry. Be careful to add water to all of the material, and not just in one spot. You don’t want it too wet in one section and too dry in another. This can be done by spraying water over the material while mixing.
Getting it Right – The Debriefing Process
Setting up a Composting system is a process, and the procedures and how the system will work best for your organization will be unique to you. Composting has long been thought of as something smelly and yucky to be avoided. So it is important that problems are fixed quickly so you can continue to divert your organic waste and produce a beautiful product in the end. This is where the debriefing can help to quickly respond and change as necessary to quickly address issues before they become a problem.
The key to a great debriefing system is to define a Clear Objective, then measure the result, determine the reason for the result and decide on the appropriate response.
- Clear Objective
- Result
- Reason
- Response
Example 1.
Objective: Divert 50% of food scraps from site using a Vermicompost system, while keeping worms healthy and productive.
Week 1 Result: 50% of food scraps from site were composted utilizing the Vermicomposting system, however there are some fruit flies in the bin
Reason: Fruit Flies have come in with the food scraps, and/or food scraps were left exposed and attracted fruit flies
Response: Ensure staff that is feeding the worms cover food scraps with bedding materials and install a fruit fly trap in worm area
Example 2.
Objective: Produce useable Compost and Divert 100% of food scraps from site using an In-Vessel Composting System, without disrupting neighboring facilities.
Result: Produced Compost product suitable for landscape use and diverted 100% of food scraps from landfill, however pervasive smells were present and we received complaints from kitchen and maintenance buildings in the area.
Response: Adjust moisture levels and add more carbon “browns” material to next batch to prevent anaerobic conditions.
While a formal Debriefing process is not required it can be helpful in keeping the project on track. A clear objective for the process is also necessary for ensuring your have met the goals and objectives of your organization in their diversion efforts.
Record Keeping
It is always a good idea to keep some sort of record for your On-Site Composting. If you are making the product to sell, record keep is required in the regulations. However, even if you are giving away the Compost, record keeping is essential to measure your impact and monitor the process.
Weight Diverted
- Measure Diversion Rates
- Measure the impact of your waste diversion efforts for environmental reporting or for more accurate estimates for general waste hauling.
- Measure reductions in GHG Emissions
- The weight of food scraps diverted from Landfill can also be converted to a reduction in GHG emissions if required for Environmental Reporting.
Compost Monitoring
- Temperature and Moisture Levels
- For most composting systems, it is also important to keep track of temperature and moisture levels to ensure that Composting is happening properly.
- When you continually monitor these, you are able to sense problems before they arise.
- Monitoring worm health in Vermicomposting Systems
- Recording activity levels, redness, plumpness, and regular worm counts will allow you to monitor worm health and notice trends before they become problems.
In the context of composting, a windrow refers to a long, narrow pile or row of composting materials strategically arranged to facilitate the decomposition process. Windrows are typically formed outdoors and are commonly used in large-scale composting operations.
Composting with red wiggler worms in a controlled and enclosed environment to produce a nutrient- rich compost called Vermicast.
Describe the Carbon Rich Materials. These are usually dry and dead materials such as fallen leaves, wood chips or sawdust, paper or cardboard, straw, etc. Typically with Composting Food Scraps, you will need two parts of “Browns” or Carbon-rich materials to every one part of “Greens” or Nitrogen Rich Materials. This ratio can be adjusted throughout the Composting process to create the best end product.
Describe the Nitrogen Rich Materials. These are usually wet and alive materials such as food scraps, grass clippings, plant material harvested while still alive, and manures. Typically with Composting Food Scraps, you will need two parts of “Browns” or Carbon-rich materials to every one part of “Greens” or Nitrogen Rich Materials. This ratio can be adjusted throughout the Composting process to create the best end product.
Refers to the relative proportions of carbon-rich materials to nitrogen-rich materials in a compost pile. For Composting, the ideal Carbon to Nitrogen ratio is around 25:1 to 40:1.