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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

Rising steam is evidence of a biological "sludge dryer" at work.

Rising water vapor is evidence of a biological “sludge dryer” at work.

In an era of ever-tightening fiscal belts, water management infrastructure is aging.

When the old sludge dryer can’t keep up, people in charge of sewage treatment systems start to look at options.

Make-do strategies may work for some municipal services,  but wastewater isn’t one of them.  A Tuesday without a yard waste pickup isn’t quite the same as a Tuesday without functioning toilets, is it?

But using energy-intensive technologies to drive water out of sludge is expensive.  And when it comes time to replace/upgrade, traditional drying solutions may no longer be the best.

In an eco-sensitive world, energy-intensive dryers are no longer viewed as good options.   Drying beds offer a low-energy alternative.   But beds are only practical where time and space abundant.

A new era and a new kind of sludge dryer

Sludge dryers have been around a long time.  But like cesspools and unlined landfills, the “old ways” are disappearing. Antiquated methods are giving way to more efficient options.  Switching to a biological sludge dryer is one of them.

Biological drying (or biodrying) is also a heat-based technology.  But in this case, the heat is “free,” generated by the enzymatic activity of feeding microbes.

Yes, the fans that maintain the microbial environment need energy.  But those fans aren’t generating and pumping heat. They’re only moving air.   That makes both installation and operating costs very attractive compared to other systems.

The same bio-technology can dry sludge and reduce mass.  Production of an EPA Class A Exceptional Quality (EQ) compost is optional. When managed to meet VAR/PFRP goals, biological drying can also eliminate liming.

The result is volume and weight reduction, plus a “less objectionable” residual. Generators can continue existing land application or landfill programs. Or the processing goal can be production of a market-grade product.

Pre-disposal, biological dryers offer reductions in transportation volumes and tipping fees.

When augmenting incineration facilities, bio-drying can positively impact those operating costs, too.

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.

A: A wide variety of feedstocks and post-processing ingredients are blended to make McGill compost products.  Our compost is manufactured from biodegradable by-products and processing residuals from agriculture, municipalities and industries, including such materials as:

  • Yard waste (aka green waste)
  • Clean wood (pallets, dimensional lumber, forestry products)
  • Vegetable scraps and culls, past sell-by or recalled products and other pre/post-consumer food wastes such as  fats, oils and grease (FOG)
  • Biosolids
  • Selected residuals from drinking water and industrial wastewater treatment, including DAF sludge
  • Agricultural by-products (manure, bedding, hatchery waste)
  • Paper and cardboard (waxed and unwaxed)
  • Compostable plastics

Click the image to read the ingredients list (PDF) from the back of the SoilBuilder bag:

SoilBuilder bag back - ingredients