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Yes, we can build a composting facility for you

Do you want to build a composting facility?  Are you —

  • A private waste management company hauling 35,000 tons or more of biodegradable waste annually and paying more than the U.S. average tipping fee to dispose of that waste at a landfill,  WTE facility, or incinerator?
  • An AD system operator wanting to maximize the market potential of a low-value digestate?
  • A landfill owner hoping to extend the life of the landfill or trying to devise a strategy to meet the growing demand for food waste composting?
  • The utility director of a municipality currently hauling compostable waste to a commercial landfill or incinerator with service contracts expiring within the next few years?
  • A food processor with food waste and other biodegradables like DAF sludge and packaging waste (broken pallets, dirty cardboard, etc.) at multiple plants within 100 miles of a central location?

If the answer to any of these questions is yes, building your own composting facility may offer cost and efficiency savings, as well as long-term pricing stability for the biodegradable fraction of any waste stream,  all while offering a real revenue opportunity from the sale of high-grade compost to plump up the bottom line.

We’re not talking about throwing some clay down in a cow pasture and calling it a composting operation. We’re discussing modern, advanced technology, high-rate facilities that can handle everything from yard waste to biosolids to food waste and biodegradable plastics with aplomb.

And if you’re currently paying high tipping fees or driving long miles to dispose of this material, owning your own composting plant may be just the ticket to price-hike independence and lower costs.

These indoor, industrial operations are weather independent, providing reliable, predictable throughput.  When coupled with a modern process and professional management, they will produce a high-grade compost product with real market value for high-end customers in the golf course, turfgrass, parks and rec, retail lawn and garden, and like industries.

One of the best things about modern, environmentally-secure composting operations is that they take up very little space compared to outdoor windrows.  Ten high-rate facilities can be built within the boundaries of one outdoor windrow operation with the same throughput.   

Because of their biofiltration systems, they can also be sited much closer to population centers than the old-fashioned variety.  Contained, encapsulated processing and aerated processing systems all but eliminate headaches like leachate, off-site odors, and failed tests as management issues. This high level of control also results in a very rapid degradation process, with primary processing completed in a matter of days.

When choosing a composting system vendor, look for a firm with deep experience and a string of financially and technically successful composting operations under its belt.  Companies like McGill (which both operates its own industrial facilities and designs facilities for others) offer a definite advantage over those without these credentials.

Decades of hands-on experience processing some of the most challenging organic waste from municipal, industrial, and agricultural streams will trump a design-only firm with no operating expertise.  

McGill’s design-build options also include operations management and product marketing.   Learn more about McGill’s DBO services here.

What is a composting facility package plant?

In the water/wastewater treatment and composting industries, a package plant typically refers to a small, prefabricated unit dropped on-site, ready to connect to the larger system.  A McGill composting facility package plant is different.

Since McGill doesn’t build small facilities, its “package” is actually a set of blueprints and specifications for an industrial composting plant pre-engineered to meet the specific environmental containment, throughput, and feedstock requirements of the owner.

Actual construction may include prefab and off-the-shelf components, but there is likely iron going up at the site and concrete to pour, too.

While the owner is still responsible for site-specific engineering,  all other aspects – structure, process, operating procedures, etc. — are provided with the package.  Initial crew training and start-up supervision is included, too.

Pre-engineered McGill facilities ensure efficient, economical operations because they are designed by folks who have been successfully building and running trouble-free, 100,000+ TPY commercial plants for nearly 30 years.      

Commercial vs. industrial composting:  are they the same? 

Commercial vs. industrial composting — no, they are not the same, though the terms may be used interchangeably on the web.  But one word has to do with the money trail and the type of organization that owns the facility.  The other is linked to operational scale and/or manufacturing approach. 

A government-owned operation is not commercial, but it could be industrial in scale. It could also be operated like a commercial facility with a similar structure and profitability goals. 

A privately-owned facility would be commercial but might not have any claim to industrial.  A small facility owned by a nonprofit may be neither.   Big, modern compost manufacturing plants may be both. 

What makes a composting operation commercial? 

A “commercial” facility infers ownership by an individual, partnership or corporation, with profits accruing to the benefit of the owners’/shareholders’ bank accounts.  “Commercial” doesn’t have anything to do with the processing method in use, facility design, throughput, technologies, or manufacturing systems. 

Composting operations owned by municipalities, counties, nonprofit organizations and the like are not commercial, because any profits realized go back into communal coffers to subsidize operations or fund other projects related to their respective missions. 

Government-owned plants are “public-sector” operations, while commercial facilities are “private-sector” operations.  Generally, nonprofits or not-for-profit entities are citizen groups and may also be referred to as non-governmental organizations (NGOs). Sometimes, an NGO may be established by individuals representing governments or agencies.  Like public-sector projects, composting facilities owned by NGOs could look very much like a commercial operation, complete with a revenue stream. 

How big is industrial scale? 

“Industrial” is a relative term, most often associated with factories and manufacturing.  In the 21st century, manufacturing infers mass production, big equipment, automation, systems, and uniformity.  Ergo, industrial scale infers a facility size that would require these things to improve efficiencies and revenues. 

When it comes to commercial and industrial composting, how big does the operation have to be to earn the designation of industrial scale?  How big is big? 

Again, it’s a relative term.  When doing research for this post, one of the findings was this article written in the mid-1990s that classified a 100-tons-per-year operation as industrial.   

Compared to the backyard compost pile, 100 tons is a big number.  But the average throughput of a composting operation in the U.S. is now approaching 4,500 tons per year.  There are 194 facilities processing more than 30,000 tons per year, some in the 100,000-plus category.   

It may be time to add one or two more zeros to the “industrial scale” definition of 1996. 

Still, size is only one indicator of an industrial facility.  But other adjectives that might be used to provide clarity are also quite subjective. 

Commercial vs. industrial composting — is “manufacturing” the key? 

The original definition of manufacturing (manu factum in Latin) literally translates to “made by hand.”  Today’s dictionaries typically describe manufacturing as making something manually or using machines.  But for most folks, the word conjures images of big buildings, lots of machinery, and cookie cutter output. 

Yet, no matter the variations in definition, one thing is clear — when applied to the manufacture of goods in the modern era, making something in an industrial setting requires production through a system that typically includes assembly lines, division of labor, a quality control program, and a sales network to move products out into the marketplace. 

Potato, Potahto 

Does it really matter whether a composting facility is commercial or not?  Industrial or not? 

The important thing is for composting operations of every description to make good compost.  How they do it or where the money goes is secondary and may not even be on a customer’s radar. 

A “commercial” facility may still imply private-sector ownership, but if public-sector owners are serious about their responsibilities to taxpayers, they’ll design, operate, and generate revenue from compost sales like the privately-owned. 

Protecting the integrity of the process and quality of the finished compost matters.  Hiring experienced, qualified compost facility operators matters.  Practicing preemption when it comes to the environment and preventing deterioration of the quality of life for the host community matters.  Providing stellar service to both intake and compost sales customers matters. 

These are the indicators of a successful composting operation, whether commercial or not, industrial scale or not.  At the end of the day, professional and profitable are among the most important descriptors for any composting facility. 

LEARN MORE: 

Making sense of research data

Evaluating organic waste management options and cost comparisons

When personal expertise is lacking, people place their trust in experts to facilitate decisions about everything from home additions to medical care.  Governing boards are no different.  They rely on the knowledge of utility directors, staff engineers, and consultants to help them make informed decisions.

But when presented with an avalanche of numbers – from scientific data to cost and operating projections – how do members of city councils and county commissions know if the information contained in that mountain of reports is accurate and unbiased?  How do they know they’re comparing apples to apples and not apples to oranges?

Placing value on studies specific to waste management can be complex.  One report might compare landfilling, incineration, and anaerobic digestion, but leave composting out of the mix.  Another may include composting, but base assumptions on an antiquated window system and not a modern, high-rate technology.  Research could unearth reports about a costly public project but never discover a more efficient, cost-effective commercial system.

This is not to suggest such errors or omissions are intentional.  Sometimes, it’s simply a case of “you don’t know what you don’t know.”  But when combined with the fact that detailed financial or operational data from private-sector owners is rarely made available in public spaces, one begins to understand the difficulty in obtaining good data on which to base conclusions and recommendations when doing composting cost comparisons.

The takeaway?  Assume all research is flawed in some way.  No one knows everything there is to know about every subject.  But there are a handful of questions that members of city councils and town boards can ask to help clarify reported numbers, level the playing field, and present a more accurate picture of construction and operational realities.

Who paid for the research?

Perhaps the most significant influence on any research project is the entity that foots the bill.  Even university research is funded by someone … and it may not be the university.  Non-profits may fund research, but they rely on the support of donors.  Government agencies can be funders, but governments are run by politicians.  When the private sector funds studies, the results may never see the light of day if unfavorable to the funding entity.  Student work may not be funded, but it’s still student work.

Was the research scientifically sound?

Some “research” may not be new research at all, but assumptions or conclusions based on a literature review that includes outdated or invalid findings.  Investigations may have been conducted in a manner that does not reflect “good science,” including a lack of statistically-representative sampling.  Some findings are more opinion poll than science.  But when sifting through millions of scientific papers for data, researchers won’t always pick up on these types of flaws.

Also know statistics can be presented in a manner that makes differences look more (or less) important than they really are.  (See an example in this SlideShare title:  Apples and oranges: comparing waste management technologies)

How old is the research data?

Unfortunately, it’s all too common to discover a case built on multiple levels of citations that eventually trickle down to data or conclusions that may not reflect present day realities.  Knowing the date and technological sophistication of the original study will help decision-makers evaluate the value/validity of the conclusions and recommendations included in the consultant’s report.

Don’t accept a current date on a citation at face value.  Follow the citation trail to the date and circumstances of the original research.

Is data based on full-scale operations using current technologies?

Was the data based on bench scale, pilot scale, field scale, or full scale?  Conclusions reached during early stages of product or system development can fail to “scale up” successfully.   Investigations based on dinosaur technologies of 20 or 30 years ago exclude advancements and enhancements made in recent years, distorting findings.

For composting specifically, ensure that systems and technologies are apples-to-apples comparisons using the most current data available.  If evaluating high-rate systems, include successful private-sector facilities, too, not just municipal.   Net expense and revenue values per ton processed can vary widely between different types of operations.

Using old data and processing systems for dollar comparisons could greatly skew conclusions when comparing composting to other waste management technologies.

Sometimes, imperfect is the only data available for composting cost comparisons

When conducting research in a field like composting, where meaningful research is scant, at best, the imperfect may be all there is.  Knowing and accepting this reality, proactively seeking out the most accurate information, and evaluating results based on a variety of studies and viewpoints can only help decision-makers make better choices for their respective communities.

Read the article:  Valuing composting as an infrastructure investment

Industrial, high-rate composting:  exploiting the power of microbes

Thirty years ago, beyond the entry sign announcing the location of a composting operation, it wasn’t unusual to see a former cow pasture crowded with long rows of rotting yard waste.

Start-up for these primitive facilities was (and still is) relatively cheap.  A windrow operation is viewed as simple and attracts owners whose primary goal is to get a facility up and running without investing much in capital.

However, in all but the most arid climates, the Great Outdoors is not that great for the microbes responsible for composting’s biodegradation.  Aerobic microbes — the stars of every bona fide composting operation — will only reach peak performance levels if they are protected from the elements, provided with an ample food supply and a bit of water, and live in an environment equivalent to a microbial Goldilocks Zone.

Bring all of these conditions together in one place, and composting doesn’t just happen.  It goes gangbusters.

Today’s industrial composting plants and advanced biodegradation systems are designed to do just that, because the realities of high-volume organics recycling often demand more than the typical windrow can provide.

Science-based recycling systems — exploiting the power of microbes

When serving metropolitan areas, composting operations can be expected to recycle everything from fecal-laden yard waste to industrial by-products — in high volumes. These facilities intake and process hundreds of tons each day.  The larger operations may be processing 100,000 tons or more per year.

Odors emanating from some of these feedstocks can be unpleasant.  The materials can be very wet.  A few will carry chemical residues that require an advanced degradation technology to render them safe for reuse as ingredients in soil amendments.

That’s why more modern plants, those tasked with managing multiple types of organics from large geographic regions, are indoor operations.  Some may still turn under that roof, but others have kicked it up a notch by employing more advanced systems (i.e., aerated static pile or ASP) instead of turning.

While a windrow tends to plod along, controlled aeration accelerates composting, turning stodgy microbes into sleek degradation athletes.  With high stamina and a voracious appetite for all things organic, these Olympians of the microscopic world bring speed, reliability and high performance to an otherwise lackadaisical process.

The industry’s transition from windrow to ASP turbocharged composting, exploiting the power of microbes and giving it the efficiency and predictability required to successfully compete with landfills and incinerators.  But this metamorphosis did not result from genetic manipulation, chemical additives or fairy dust — it was simple biology.

That’s it.  Not engineering.  Not artistry.  Just biology, specifically, exploiting the power of microbes.

Prior to some notable research by scientists beginning in the 1950s, folks may have known how to keep a compost pile chugging, but not why their management efforts worked.  But once researchers figured out the why, they were able to control the process by giving aerobic microbes exactly what they needed to survive and thrive (air, water, food, temperature) in the right amounts and within ideal ranges.

They discovered composting’s Goldilocks Zone.

By the 1990s, this academic exercise had captured the eye of the commercial sector.  With some tweaking to improve efficiency and profitability at scale, a robust, predictable process emerged, one with the ability to cost-effectively recycle high volumes of organics.

But back to those microbes…

After many trials and several errors, industrial composting moved into the waste management mainstream.   But to make biology work as the power behind the progress, both designers and facility operators had to grasp, embrace and deploy a few scientific principles.

At the core was a rudimentary understanding of the two broad categories of biodegradation processes – aerobic and anaerobic.  Each identifier reflects the environment in which the microbes live.

Aerobic organisms require air and water, but like people, they cannot breathe under water.  Conversely, anaerobic microbes are like fish – they’ll die when exposed to air.

Anaerobes live and thrive in much wetter conditions than can be tolerated by aerobes. Both prefer a moderate temperature zone.  Anaerobes will die off at around 150 degrees Fahrenheit (F) or 65.6 degrees Celsius (C).  While aerobes can tolerate more extreme temperatures, the most active phase of aerobic composting takes place between 55 and 155 degrees F (12.8 to 68 C), with a preferred range of about 122-140 degrees F (50 to 60 C).

Anaerobic fermentation generates methane, which can be a good thing if captured and used for heating, cooking and generating electricity.  If not, then it’s a bad thing, a potent greenhouse gas.  When anaerobes are at work, certain compounds are created during intermediate degradation stages that result in unpleasant odors.  That is why some wet, decaying materials carry an offensive stench — the rotting organic matter has “gone anaerobic.”

But an aerobic process neutralizes odors by creating drier conditions, killing odor-causing anaerobes.  Methane is not generated during a well-managed aerobic composting process, and the resulting carbon dioxide emissions are considered carbon-neutral since the gas generation volume is the same as if the materials degraded naturally.

Beneficial bacteria and fungi are among the aerobic microbes that make compost “happen.”  About 2,000 species of bacteria and 50 species of fungi are ably aided in their degradation efforts by a zoo of macro-organisms like beetles and worms.  However, aerobes are the worker bees of the compost pile.  They break down organic matter at the chemical level as opposed to the physical rending of the macros.

Feeding on organic waste, aerobes power the engine that drives moisture from the composting mass, degrades pollutants, and eliminates odors.  The enzymatic action associated with aerobic digestion breaks molecular bonds, releasing by-products (heat, water, carbon dioxide) in the form of steam.  Once these microbes have consumed all available food, they die fat and happy, their microscopic bodies becoming part of the residual mass.

In a controlled composting process, a temperature drop signals a decline in food supplies and a correlating reduction in microbial populations.  Degradation slows, but still continues at the lower temperatures associated with compost curing.

If left to time and nature, organic matter will continue its disintegration until nothing remains.  But long before that happens, biodegradation enters a phase where the residual is relatively stable, while still microbiologically active and chock-full of both macro and micronutrients.  With its soil-like aroma and appearance, the material is pleasant and easy to use – a critical requirement for any product intended for widespread general use — and really, really good for rebuilding depleted topsoil.

This stuff, of course, is compost.

Microbes just keep going and going and…

When talking microbes, conversion of waste to valuable product is only half the job.  Once that compost has been added to soil, the little critters take on even more tasks:

  • DEGRADATION OF POLLUTANTS – microbes break down synthetic compounds to neutralize the impact of things like petroleum products and fertilizers/chemicals that can negatively impact both soil and runoff quality.
  • IMPROVE NUTRIENT UPTAKE – microbes convert nutrients to plant-available form, making more food available to plants and reducing the need for synthetics.
  • IMPROVE DISEASE RESISTANCE — microbial activity is responsible for the plant disease suppression associated with compost use.

The influence of science on facility design

The biggest problem with outdoor operations is not weather, per se, but the fact that weather cannot be controlled.

If a composting mass needs moisture, rainfall can be a welcome addition.  While it’s common for the sides of a compost pile to “crust,” discouraging rain infiltration, piles can be flattened and then concaved on top to capture rainfall for slow infiltration over time.  In this regard, rainfall can be a compost manufacturer’s friend.

But excess rainwater rolling down the crusted sides of a pile will settle into pools of “black liquor” (a.k.a. leachate) at the base.  Leachate and associated runoff contaminate ground and surface waters, attract flies and harbor unpleasant odors.  If the pile gets too wet too soon, pathogens rebloom.  When composting outdoors, a heavy rainfall can set the stage for nuisance complaints and regulatory intervention.

Conversely, maintaining acceptable processing conditions outdoors during dry spells requires sprinkler systems or a hose brigade if the microbes and the process are to be saved.

Add complications like high winds and ice storms to the mix, and the operation of an outdoor facility becomes more about battling Mother Nature than recycling organics.

Having to reprocess ruined piles and windrows adds cost and retards throughput. When hundreds of tons of waste arrive at the gate each day, a stuttering throughput rate can cause massive pile ups that compound and exacerbate the weaknesses of outdoor facilities.

Exploiting the power of microbes means protecting the creatures from the vagaries of weather is a top priority for modern facility designers.  Solutions can range from a shed roof to encapsulation to full facility enclosure.  Each rung on the containment ladder offers an elevated level of environmental control and protection, as well as fewer operational complications.

On that list are the elimination of materials handling woes related to weather delays and the ability to capture inside air and processing off-gases for biofiltration.  Indoor facilities can also make a composting operation more palatable to the locals by providing visual camouflage and sound buffering.

Making biology work for day-to-day operations

Putting a roof over a composting operation may remove many headaches from the manager’s plate, but design is only as effective as the people running the place.  Any composting facility — from the most basic to the most sophisticated — can still run into trouble if mismanaged.

Exploiting the power of microbes requires a multi-faceted strategy.

Feedstocks like food waste and biosolids can be wet and odor-laden when they arrive at a composting facility.  One of the top priorities for modern composting operations is to get these types of materials blended with dry amendment and aerated as soon as possible to kill off anaerobes and encourage the proliferation of aerobes.

But if the blend isn’t right, a batch can be doomed before the admixture ever hits the composting pad or aeration floor.  Wet or dry pockets impact microbial movement throughout the composting mass.  An irregular texture means patchy distribution of target compounds and uneven exposure to the microbes.  Pockets of untouched raw waste can survive an otherwise successful process, leading to regeneration of odors and reblooming of pathogens.

Particle size needs to be consistent to achieve an even degradation rate for all blend ingredients.  Material placed on the composting pad should not be compacted.  Aeration pipes must be free of debris.  Windrows may need more turnings than required by regulations to keep the process humming.

Many items on the list of best management practices (BMPs) are common to all composting operations, from backyard to industrial.  Many items on the DO list relate to the creation and maintenance of an ideal environment for the microbes responsible for biodegradation.  The DON’Ts focus on discouraging of the kind of microbes that cause and perpetuate odors.

But no matter the design or process, people are ultimately responsible for making the science work as it should, keeping those all-important “bugs” happy and ensuring a trouble-free operation.

LEARN MORE

Calculating C:N ratios – hitting the sweet spot when blending multiple feedstocks

Cooking may allow the chef to add a pinch of this and a daub of that to create an incredibly edible meal, but more exact measurements and methodologies are required for successful baking.  That’s because cooking is mostly about building and enhancing flavors.  Baking is about understanding and exploiting science.

Composting is about science, too.  Just as curdled custard and flat cookies are indicative of science gone awry, a sluggish composting process and offensive odors are signs someone failed to adhere to the science.

One of the common culprits of composting-science-gone-bad is getting it wrong when calculating C:N ratios.

C means Carbon.  N stands for Nitrogen.  Together, they influence microbial feeding activities.  C provides energy and microbial cell structure while N is linked to proteins, enzymes and other substances integral to cell growth and other biological functions.

The trick, of course, is to hit the composting “sweet spot” with a carbon-to-nitrogen ratio of about 30:1 for the initial feedstock blend.

Forget about “brown” and “green” for calculating C:N ratios

The ubiquitous brown:green rule of thumb for composting — brown materials are carbon, green are nitrogenous — is often promoted to help the backyard composter recognize differences in materials.  But one cannot categorize feedstocks based on color alone.

Coffee grounds may be brown, but they are rich in nitrogen and can actually serve as a substitute for manure (which is also a brown).  Therefore, coffee grounds are “green.”  Peanut shells, also brown, have a near-perfect C:N ratio for composting of 35:1 without combining with any other carbon or nitrogen.

Adding to the brown-green confusion is a mistaken belief that the ratio relates to volumes of brown material and volumes of green, as in 30 buckets of sawdust to one bucket of cut grass.

It does not.

C and N values are derived from the actual carbon and nitrogen content of the individual blend ingredients, not by feedstock volumes, and those numbers are derived from materials testing or generic charted values based on someone else’s tests.

At a micro-scale, the margin of error associated with color confusion may be small enough to make little difference in odor generation or degradation rate for a home compost pile.  But at industrial-scale, calculating C:N ratios needs to be more precise.

The best method of determining carbon and nitrogen content is feedstock testing.  Then, calculations can be made to determine the mix.  When testing isn’t possible or practical, assumptions can be made based on charts like this one.  Washington State University also makes a Compost Mixture Calculator available online that does the math.

C:N impacts on the composting process

C:N is an indicator of the nutrient content of any given material.  Sometimes, a C:N ratio may be expressed as a single number — i.e., 45, 30, 13, etc. This means 45:1 or 30:1 or 13:1.

A lower “C” number indicates higher nitrogen.  Higher Cs indicate more carbon.

For a composting blend, anywhere in the 25-35:1 range is considered good.

A higher carbon content will slow the biodegradation process.  But if carbon content is too low, odors and anaerobic conditions can become management issues.  Too much nitrogen can also raise pH, killing off desirable microorganisms.

Carbon content will naturally drop during composting as microbes use it for energy.  Carbon is also released as CO2.  Nitrogen, however, gets recycled, so the amount at the end of processing is the same as it was in the beginning.

C:N impacts on compost use

The 30:1 ratio is the Goldilocks Zone for composting, but a typical finished compost might have a ratio of 20-25.  (Soil microbes prefer a C:N ratio of around 24:1.)

When added to the soil, composts with higher numbers can encourage microbes to lock up any available nitrogen for their own use, leaving less for plants. Lower ratios reduce the likelihood for food (nitrogen) competition between plants and microbes, since the feeding microbes will still leave plenty of N for plant growth.  Even at a 10-20:1 ratio, there will still enough carbon and nitrogen to allow plants and microbes to successfully share.

However, when the C:N ratio drops below 10, degradation rate for organic matter becomes very high, negating some of the benefit of compost use.

Soil tests, product tests and a chat with the local agricultural or horticultural extension agent should tell growers what they need to know to maximize yields based on the C:N ratio of finished compost.

LEARN MORE:  Carbon to Nitrogen Ratios in Cropping Systems

Preemption vs prevention:  Choosing higher standards for composting facilities

Preemption vs. prevention — do you know the difference?  From odors to leachate to low-value products, at almost every stage of facility development and operation is a preemptive choice that will greatly mitigate or eliminate the most problematic issues plaguing composting operations.

First, understand that preemption is not the same as prevention.  Prevention is picking up a banana peel before someone slips on it.  Preemption is not buying the banana in the first place.  Prevention is building berms at composting facilities to contain leachate.  Preemption is combining design, technology, and management to make sure no leachate is generated.

From siting to intake to final product storage, there are preemptive choices that provide superior protections and efficiencies over more traditional options.

Admittedly, preemptive siting and design options tend to have higher up-front costs.  But building and operating according to the preemption principle can result in composting facilities that work better with fewer headaches, lower operating costs and higher revenue.

Conversely, a low-end approach can ultimately cost more when factoring revenue loss, increased expenses, reduced throughput, failed tests, poor product quality, regulatory headaches and public relations problems into the design and management equation.

Preemption vs. prevention for site selection

In the case of composting facilities and their neighbors, it is distance that makes the heart grow fonder.  Regulated buffers are minimums, not the ideal.  As a preemptive measure, put the largest buffers possible between active work zones and property boundaries.

Use vegetation, including vegetated berms, to shield operations.  In addition to visual camouflage, well-designed and strategically-placed vegetation and woodland buffers also contribute to noise and odor abatement.

Preemption vs. prevention for odor mitigation

There’s no way to sugar-coat the truth:  Composting facilities are in the business of recycling putrescibles.  The root of the word putrescibles is putrid.  Ergo, facility management can be problematic if the facility has not been designed to tackle odor generation from the get-go.

Odors are generated during biodegradation by anaerobic (without air) microbes.  Typically, this means conditions within the feedstock pile or composting mass are too wet to support aerobic (with air) microbial populations.

The whole point of composting is to create an environment that will encourage the proliferation of the specific aerobic populations responsible for rapid breakdown of complex compounds and neutralization of odors.

That means getting especially odorous feedstocks into blending ASAP and keeping air flowing continuously — in the right amount– throughout processing and curing.  Most of the composting facilities in existence today do not have that capability, because they rely on periodic mechanical turning to aerate the pile.  Advanced composting methods will use some form of automated temperature feedback system to moderate temperatures and keep the piles aerated 365/24/7.

While not impossible, open air composting using any method will have a devil of a time creating and maintaining aerobic conditions if the climate is anything other than arid.  Rain falling on an exposed composting pile can give anaerobes the competitive edge, encouraging the rebloom of pathogens and allowing odor regeneration.

Moving an operation totally indoors will also allow the capture of emissions from all work zones,  including off-loading and blending, as well as facilitate the extraction of stale air from processing bays.

Once collected, this air can be channeled through a biofilter prior to venting.

Choosing an indoor facility with biofiltration is an example of preemptive design.

Preemption vs. prevention for leachate management

Leachate may be generated by rain failing on unprotected piles or the draining of excess moisture from wet feedstocks.  Leachate is the dark “liquor” that pools in open composting yards, contributing to odor generation and the proliferation of flies.

Berms, piping and collection pits are tools used in composting to channel and contain leachate.

The goal of these preventative measures is to capture leachate before it escapes property boundaries or runs into surface waters.  The leachate can then be treated onsite, reused during blending to wet dry feedstocks or piped to a wastewater treatment facility.

Immediate blending of wet feedstocks with the appropriate types/amounts of dry amendment, along with the prevention of rain infiltration, will all but eliminate leachate as a management issue.  Minor seepage from standing piles can be absorbed by dusting puddles with dry compost, which is then returned to the head of the plant for reblending.

Proper blending is an example of preemptive management.  Taking steps to prevent rain from coming in contact with feedstocks and compost piles is an example of preemptive design.

Preemption vs. prevention for product value

Product value is based on multiple influences including feedstock selection, blending, processing and, finally, storage.

Preemption plays a role in feedstock selection by sourcing the best ingredients and avoiding those that add little to the final product or, even worse, lower the value.

Blending to produce a homogeneous mix without marbling or clumps results in an admixture that exposes all raw materials to beneficial microbes and facilitates even air flow throughout the composting mass.

Covering product during processing and long-term storage ensures high market value and maximum revenue from product sales to high-end users like landscapers, athletic field managers, golf course superintendents and landscape supply retailers.

Failure to establish a professional marketing and sales program can result in large piles of unsold product or sale of product below market value.  Hiring experienced sales professionals can make a difference in the overall efficiency and profitability of an operation.

All of these are examples of preemptive management practices.  None are linked to a specific facility design or composting technology.

Every composting operation can practice preemptive management.

McGill Environmental Systems is a commercial organics recycling and compost manufacturing company.  Also known as McGill Compost or simply McGill, it incorporated in 1991 in North Carolina.

Who is McGill?

We are one of the oldest and largest advanced-technology composting companies in the world.
  • We own and operate industrial composting facilities in the North Carolina, Virginia, and Ireland.
  • We employ about 100 people worldwide.
  • We use an advanced composting technology to convert biodegradable materials into high-value compost products for commercial and professional markets.
  • We offer related services like sludge dewatering and transportation.
  • We process indoors and use computers to provide the maximum level of process control.  This results in a fast, efficient process and high-quality compost products.
  • We design, build and operate composting facilities for ourselves and for others.
  • We market a line of branded compost products to landscape suppliers, golf courses, athletic fields, construction contractors, stormwater managers and farmers.