White Paper-Biomass: Waste First, Then Fuel

Biomass covers a wide range of organic plant-like matter and depending on the viewpoint is either waste material or a desirable fuel, but can also be both. When we speak of waste, we usually refer to man-made waste, unwanted or discarded matter. Then there is also natural waste; biomass that is part of nature’s life cycle. Ever since life on earth emerged, that natural waste cycle has maintained a balance. Living things die, decompose and are returned to the earth to support new life; that includes woody biomass or trees. Most trees die eventually from old age, as their defenses to fight droughts, disease and insects diminish over decades, and those that don’t, like the Redwood, just keep growing taller and eventually reach a point where gravity counteracts the supply of nutrients up the tree trunk.


That balance started to be tilted mainly with the onset of the industrial revolution and explosion of the world’s population. On one side, the civilized world started to produce an abundance of waste material from MSW to sewage sludge that was mostly just abandoned somewhere, and it took many decades before waste handling, minimization and recycling scheme were devised, implemented and now often mandated.


On the other hand, man’s sprawling movement into the countryside, in and near woodlands and its management of the forest, started to upset the balance there. Logging and clear-cutting affected the forest’s ecosystem and systemic forest fire suppression efforts caused a change in forest health weakening the tree’s natural defenses to fight droughts, diseases and pests. This resulted in biomass waste material that the natural cycle could no longer keep in balance. 


How much woody biomass is there in the world?  Much is debated about recycling of discarded materials, waste reduction and minimization, but biomass waste is hardly mentioned.  It is as if wood debris is somehow one of nature’s byproducts that would take care of itself. The fact of the matter is, that there is so much biomass waste, and more amassing daily, that techniques to keep up with reasonable ways of dealing with it have fallen pitifully behind. We continue to chip, grind and truck green waste from curbside collection, and often agricultural operations, to landfills shortening the useful life of them at high costs and at the same time causing serious pollution from the Diesel engines employed and the decomposing matter in the landfills; all bad climate change forcing agents. Matters are often made worse by narrow minded agencies or organizations that on one side prohibit the dumping of wood waste into a landfill but offer no alternative or some that are riddled with falsehoods. The much-hailed turning of wood waste (and sometimes harvested wood from woodlands) into little pellets while using hydrocarbon fuels to accomplish that not without, again, polluting the air, has been upset by such unrelated events as China no longer accepting waste, including wood chips or pellets from abroad and government subsidies dwindling. We see that dilemma being exacerbated in Australia, for example. Few technologies have advanced to combat the problem and the result in many places is open fires burning the debris; fires started intentionally or by accident.


In short, there is such an overabundance of woody biomass waste worldwide, even without counting the endless tons of waste from natural disasters, like hurricanes, tornadoes, typhoons or wildfires, even earthquakes. Only an insignificant amount of that wood waste is recycled, and mostly by inefficient composting. 


The US EPA reports that in 2015 in the US wood waste and yard trimmings combined were 51.02 million tons and of that 21.86 million tons ended up in landfills. Wood waste accumulated from forest management, wildfire rehabilitation and natural disaster is not included in the EPA assessment published in 2018. 


Today we have literally millions of trees, more than 129 million as of 2018 to be more specific, in the US alone that are dead either standing or fallen to the ground that represent natural woody biomass. 


One would think that with this tremendous natural energy resource that is being replenished naturally at no cost, there would have spawned a myriad of technological advances to first get rid of it once and for all and, secondly, to repurpose or recycle it where energy extraction would be the most plausible goal.


Why has this not happened? Primarily, because the focus has shifted from considering the waste a waste, unwanted matter as it is, to calling it a fuel. Two problems arose, other than there was too much waste to begin with: as a fuel, the extraction and final form of energy had to compete with wind and solar, two technologies that have come a long way to be viable, and second, traditional hydrocarbon-based energy became so cheap that biomass energy could not compete in the market place. Next, governments devised tax credit and subsidy schemes to shore up the ailing biomass waste to energy endeavors. Why? Not because we needed more energy, but because we needed a waste disposal solution. Now the dilemma is compounded. A WTE plant, say a gasification power plant costing millions of dollars, is to function as a waste disposal operation. That could not work because by design the plant was to keep biomass fuel consumption low with maximum energy output, as the fuel was expensive to preprocess into precise chips or pellets to make the system work, and the fuel had to be transported over ever longer travel distances since the biomass supplies are diminished over time.  Additionally, the expensive preprocessing is again seriously polluting, as it needs petroleum-based fuels to function.


This led to most biomass WTE plants collapsing, even though many were being supported by huge amounts of the tax payer’s money. The biomass waste had no place to go. Authorities outlawing open pile burning in agriculture and fighting to keep wood waste out of landfills met with a seemingly unsurmountable dilemma.


One needed a technology that could start eliminating the huge quantities of biomass waste and eventually, even find ways to extract the energy from it as well. The practice of open wood waste burning long used by man and Mother Nature emerged in the forefront with high-tech air curtain firebox machines. They have been regulated by authorities and found to be very environmentally friendly. If designed properly and operated accordingly, they are affordable, easy and economical to run, and importantly, they are portable. They can be deployed easily and relocated as need be to minimize transporting the waste material. Air Burners in Florida is the world leader in this business and ships its products worldwide, and Air Burners machines have been the choice for massive clean wood waste elimination by governments and industries.


Recognizing the biomass industry’s void and failure in developing viable energy conversion schemes, the engineering teams of this Florida company set out to overcome that. The goal was to design a machine that does not suffer from the missteps of competing schemes. In that, the machine -

  1. 1. Must eliminate massive quantities of biomass waste
  2. 2. Must be portable to take it to the waste and not the other way around and to relocate it following the waste
  3. 3. Must be affordable, cost much less than a large grinder
  4. 4. Must be environmentally friendly per EPA or other authority standards
  5. 5. Must be easy to operate and at lowest cost
  6. 6. And must produce electric and thermal power extracted from the waste in order to power itself and other equipment in the yard or send excess power into the public grid
  7. 7. Must be made in the USA


There is only one such system available worldwide today: The portable air curtain burner system coupled with a power module to deliver both electric and thermal energy called the PGFireBox System. It allows the massive elimination of the wood waste which must be the primary objective. This once futuristic machine is now on the market and readily available from Air Burners in various output ranges as follows: 100kWe/1MWth (PGF-100), 500kWe/2.5MWth (PGF-500) and 1MWe/5MWth (PGF-1000). They all come with air-blast cooling modules, though cooling water from a well or large lake is always a good alternative where available. All systems can be torn down sily for relocation closer to the source of biomass waste. Their installed cost is so reasonable, that in most placements, the systems pay for themselves in a matter of months or just a few years. That is plausible, because the process encompasses total waste elimination and the avoidance of tipping fees or other disposal costs, plus the associated transportation and grinding costs which add up quickly.


We must be aware that the amount of biomass fuel for energy production will never end, however the economic conversion to energy in most established biomass plants would suffer catastrophic consequences, once the nearby biomass sources have dried up and the cumbersome preprocessing and ever-increasing transportation costs with larger travel zones could no longer be sustained, with or without government subsidies.


What this also means is that there is more biomass fuel available that could possibly be converted to energy, no matter what system would be employed. In other words, we do not have an energy problem to solve, as there is plenty of inexpensive energy abound, but we do have a very critical waste problem with biomass waste being accumulated at an incredible pace with few places to go; and that should never be a landfill. Too much wood is already in landfills decomposing slowly releasing methane, a worse Greenhouse Gas than carbon dioxide and possibly causing leachate problems with groundwater as well.


The management of waste with the aim of minimization and maybe someday total elimination, and the rehabilitation of the oceans and land dumpsites from waste, must be of the highest priority for every country in the world. Biomass waste, accumulating from natural occurrences and man-made activities, must receive equal attention, first as a waste and then as a possible fuel for energy extraction or repurposing into biodegradable material to replace plastics.


Published with MSW

Feb-April White Paper 2019