Posts

Is it really a good idea to make compostable waste go away and never come back? 

Each year, taxpayers collectively spend millions of dollars to burn or bury compostables.  Much like a tribe of ubiquitous Gollums, they just want garbage — the biodegradable and putrefying fraction of the municipal solid waste stream – to go away and never come back. 

The desire to make disagreeable discards disappear into fiery furnaces or burial mounds is understandable.  But is it wise?  Is it fiscally responsible?  Is it really a good idea to make organic waste go away and never come back? 

Nature recycles everything 

Rocks weather and erode, creating sediment. With heat, pressure, and time, that sediment becomes rock again.  Plants and animals feed and drink from the earth, die, and decompose to replenish the soil that will sustain future generations of flora and fauna.  Water drops from the sky as rain, filters down to aquifers, upwells and evaporates back to the clouds to fall once more. 

In a fantasy land, it may be possible to keep using resources without a thought to replenishment.  But in the real world, organic waste – the decaying residuals of once-living things – must be recycled back to the soil to maintain life-critical soil functions.   

Some seem to think the destruction of organics to make energy is more important than rebuilding soil.  But pushing an organic-waste-to-energy agenda by sacrificing the soil makes no sense. Humans managed to survive for millennia without electricity and centralized energy systems.  Without soil’s life-essential contribution to food and clean water, people face extinction in weeks.  

So, which is more important, energy or soil? 

Make energy and rebuild soil?   

Organic waste from developed societies includes all types of vegetation, food, manures … even compostable plastics.  When turned into a quality compost, these once-lost resources can be used by anyone anywhere to replenish depleted soil.   

Happily, making energy and building healthy soil does not have to be an either/or proposition.  It is possible to extract energy from organic waste without destroying the beneficial properties that make it valuable to soil.   The organic waste streams from these processes can then be used as feedstocks in the manufacture of compost products. 

Unhappily, energy production from biomass is one of the most expensive ways to make energy.  Even solar and wind power can be more cost-effective. 

Furthermore, bioenergy technologies based on anaerobic digestion of organics are still too pricey to be practical in many places.  Where they do exist, the waste stream (digestate) is not always put to highest and best use (i.e. composted).  Instead, residuals may be landfilled or relegated to low-dollar-value reuse. 

But one day, as more communities opt to restore natural soil replenishment cycles and energy generation technologies become more efficient, extracting energy from biomass, followed by composting and compost use, can become the system of choice for organic waste management. 

In the meantime … 

The importance of healthy soil 

Where humans live, topsoil has been scraped away or eroded.  Nutrients are used up.  Compaction has destroyed the pore spaces essential to the transport of air, water, and microbes.  Without a regular infusion of new organic matter to correct these deficiencies, soil dies.   

There are lots of processes for generating energy, but there’s only one way to replenish disturbed soils in developed areas – feed them a good, wholesome diet derived from organic waste converted into compost.   

From farms to lawns to sports fields, soils require periodic applications of compost.  There’s no other way to easily and economically provide soil with everything it requires to retain water, nurture vegetation, and create the type of environment soil microbes need to support nutrient uptake, contribute to disease resistance, and degrade pollutants. 

The best news? In many metropolitan areas, efficient, high-rate composting – the type needed to successfully manage big, urban waste streams – costs no more than landfilling or incineration.  Often, recycling at a modern, industrial composting operation can be more affordable than traditional disposal.   

Composting makes organic wastes go away, but they come back as enriching soil amendments.  Biodegradables need to keep recycling, just like they have since the beginning of time. 

Breaking the natural soil cycle by incinerating or burying compostable waste is a bad idea that should go away and never come back.

VIEW THE SLIDESHARE:  Addicted to convenience

How to make compost fast

The desire to make compost fast can be driven by space restrictions, the need for more product, or simple impatience.   It’s a common goal for composters everywhere, from the backyard to industrial facilities.

Unfortunately, wishing will never make it so.  The speediest course from raw feedstock to finished quality compost is a series of steps controlled by the person doing the composting.  Skip or bungle just one, and biodegradation could slow or even grind to a halt.

It doesn’t matter whether you make compost by the tumbler or by the ton.  If you want to make compost fast, follow these steps:

  1. Consider carbon-to-nitrogen (C:N) ratios when mixing every batch.  Base mixes on the C and N percentage of each feedstock, not feedstock volume – it’s not buckets of “brown” to buckets of “green.”   Learn more about calculating C:N ratios.
  2. Get the blend right with uniform particle size, good porosity, no clumps or marbling of feedstocks.  
  3. Maintain a desirable moisture level throughout primary processing.  Don’t expose the composting mass to weather or allow it to dry out.  Add moisture, as needed.   Learn more about composting moisture levels.
  4. Keep air moving through the pile.  This allows microbes to breathe and removes excess heat.  Invest in a temperature probe and adjust air flow to maintain ideal temperatures.       

Master these basics to make compost fast.

Does composting release CO2?

Carbon dioxide (CO2) emissions from the composting mass are classified as biogenic. This means the same amount of gas is emitted during decomposition whether the organic material is composted or degrades in a natural setting.  Therefore, these emissions are considered carbon-neutral.

Compared to waste management alternatives, it’s the best of the bunch.

Other emissions sources, however, like those from equipment operation,  do add to the size of a composting facility’s environmental footprint.  These are nonbiogenic, a.k.a. anthropogenic, emissions.

This factsheet provides a good topic overview that includes values for helping composting operations with emissions calculations.

 

food waste composting includes biodegradable plasticsHarvesting practices, processing systems,  grocery store discards, food prep,  and plate scrapings all contribute to food waste.

According to the U.S. Environmental Protection Agency, 2010 saw the generation of 34 million tons of food waste, almost 14 percent of the total municipal solid waste (MSW) stream.  Only 3 percent was recovered/recycled.  The remaining 33 million tons was wasted, the largest fraction of the total MSW stream to be landfilled or incinerated.

That same year, the U.S. composted about 20 million tons of waste. To compost all food waste currently landfilled or incinerated, we will need to more than double current capacity.  A commitment to zero waste for all organics pushes capacity requirements even higher.

But there is plenty of room at the composting table.  If the industry is to meet the challenges of zero waste, we need to fill those empty chairs.  Fortunately,  interest in collecting food waste from local restaurants, grocery stores and the like is on the rise.

In fact, every now and then, some hopeful composter will contact us.  They seek advice about getting into composting on the community level.

We always offer encouragement, and for some very good reasons.

The ‘greenest’ option may not be viable

Some of us have been environmental activists long before green became everyone’s favorite color.  We know —

  • collecting food waste from the neighborhood,
  • composting it in the neighborhood, and
  • using it to grow food on urban farms in the neighborhood

may be the most desirable option from an environmental standpoint.

But these types of micro-projects are not always practical or particularly viable. Recycling things like plastics, metals and glass is an expensive proposition.  So is recycling food waste – if you want to do it right.

The economics and/or logistics of composting sometimes prohibit action on the neighborhood level.  When that happens, a regional solution can be the best choice for crafting a disposal-to-reuse cycle that works.  Networking with proactive individuals and groups within communities presents opportunities for companies like McGill.

Voluntary collection requires route density

Most of our existing customers generate by-products and residuals by the ton.  But hauling services for low-volume commercial and residential generators are another matter.

Generally, volunteers don’t provide the volumes or route density needed to make the economics work for big tonnage haulers.  Curbside collection requires recycling mandates.

However, smaller companies and community groups are stepping up to the “plate” to fill this gap with curbside services.  They are collecting food waste and other organics by the bin or cart, transporting to permitted composting facilities like McGill.

National Organic Process Enterprises (NOPE) out of Richmond, Va., and Compost Now, based in Raleigh, N.C., are just two companies on our radar.  And there are many more popping up across the country.

It seems to be a successful model for enviropreneurs when the composting facility is located close to a metropolitan area.  No need for food waste transfer stations.

The homeowner or business is able to recycle food waste.  The collection entrepreneur builds a viable business.  We use the material to make compost.  The homeowner or community uses the compost to improve soil.  Everybody wins when we all work to lock the recycling loop for organics, including the environment.

Obviously, there is plenty of room at the composting table for operations of every size. From backyard to community to regional scale, each fills a specific niche.  All will be needed if we, as a nation, are going to stop wasting such a valuable resource.

Up next:  Food waste composting – not as easy as it sounds, not as hard as it seems.

art-pencil-apple-dividerWhen it comes to diverting food waste , there’s still a long row to hoe.

North Carolina released a 2012 study revealing an annual food waste generation rate of over a million tons in the state.  The volume represented at least 12 percent of NC’s municipal solid waste stream. It was slightly lower than the U.S. as a whole, which was around 14 percent in 2010.

As a nation, we’ve made solid progress in recycling some materials.  But food waste isn’t one of them.  The national food waste recovery/recycling rate is only around 3 percent.  What remains — 33 million tons — goes to landfills and incinerators.   North Carolina is doing a bit better than that.  It diverts about 60,000 of those 1 million-plus tons generated or about 6 percent.  But that still puts 94 percent into the disposal stream.

Scott Mouw, North Carolina’s recycling program director, calls food waste “the next frontier for reducing landfill dependence.”  We say it’s that and more.  Food waste, when composted and used as a soil amendment, is a key to reducing stormwater volumes and related pollution.  Its use cuts dependence on chemicals and foreign oil, saves water, and so much more.

Landfills and WTE — diverting food waste?

Burning and burying resources are wasteful and environmentally-unfriendly practices.  Plus, these types of disposal can be more expensive than recycling systems with composting as the core technology.

It’s time to abandon the exuberantly wasteful practices and technologies of the old century and get on with the new.  Building a modern waste management infrastructure is both environmentally and economically responsible.

NCSU Park Scholars

NCSU Park Scholars with McGill president, Noel Lyons (2nd from right)

For a group of students exploring links between economics and the environment, what better place for a tour stop than the McGill Regional Composting Facility at Merry Oaks just south of Raleigh, NC?  Students from the Park Scholarships program at North Carolina State University made a late-March visit to hear Noel Lyons, McGill president, talk about the company’s milestones and challenges through 20-plus years of growth.

cary promotes compost useLast month, town officials in Cary, North Carolina, organized another of their popular compost giveaway events.  Residents loaded up free compost manufactured from waste materials generated by the community.

As a result, the line of cars, trucks and SUVs often spills into the street for Cary compost distributions.  This year, vehicle count for the “while it lasts” divvy-up was 204.

Sending waste off to be recycled only takes us halfway around the recycling loop.  To close it, people must use the products manufactured from those residuals and by-products.

The folks in Cary get it.  They also get gallons of irrigation water saved.  Other benefits include stormwater runoff reduction and lower water treatment costs.  Plus, every patch of suburban lawn or sports field amended with compost sequesters carbon.