ZeroCO2 CHP systems (Heat only or Heat and Power) furnaces and boilers

We have 3 distinct sustainable commercial heating systems (hot water boilers) including the ZeroE, ZeroC and ZeroT furnace series as well as associated fuel handling systems, ORC power generators and ZComposters.

Installation and Service

Our team goes the extra mile to assist in choosing the right system for our clients needs. We take pride in providing continuous ongoing assistance in the selection of primary and auxiliary equipment, required for optimal functioning and operation. Our experienced installation team is happy to assist in custom turn-key projects and services required after installation.

Specifications and Details

Fuel Disintegration

The fuel processing begins in the shredder where the straw is disintegrated into smaller, manageable particles. Interruptions or delays in reclaiming fuel can occur because of undesirable fuel properties (i.e. poor flow, compaction, frozen chunks, oversized material or contaminants), so fuel preparation is critical to the operation of the entire system.

Fuel Transfer

From the shredder, the particulate fuel is moved by a conveyor or auger to the fuel injection system. The fuel injection system feeds the fuel into the primary combustion chamber utilizing a mechanical plunger or twin augers.

The back flow of combustion flames and gases through the fuel entry is controlled by an automated fire door.

Primary Combustion Chamber

The primary combustion chamber is an enclosed area where drying, pyrolysing and oxidizing occurs. The fixed rotating grate supports the fire bed and allows for underfire air to be blown up through the fuel. Effective oxygen supply and control is critical to ensure complete gasification without complete combustion.

Ash collects below the grate and is removed automatically by an auger. In general, ash from biofuel burning is not considered hazardous waste and can be placed in local landfills. However, most ash is an excellent soil additive and will be of interest to local gardeners and farmers. Proper ash management is critical, as the non-combustible inorganic (mineral) content of biomass can become significant, depending on the type of fuel utilized. Inherent ash is generally low in clean wood (0.5%), higher in bark (3.5%) and significant in annual crops such as straw (6.2%), but usually consistent within a fuel type. Ash content is usually expressed on a dry basis, i.e. the weight of ash as a percentage of the total moisture-free fuel weight.

Secondary Combustion Chamber

The hot exhaust gases exit at the top of the primary combustion chamber and pass through a refractory duct into the secondary combustion chamber. Oxygen is added to the refractory duct. As the gases flow from the primary to the secondary chambers, the injection of oxygen ignites the gases, allowing gas combustion to take place in the secondary chamber. The quantity of heat released during the bio-fuel gas combustion is dramatically increased to approximately 2,500 degrees Fahrenheit. Extremely high temperatures are maintained in the combustion chambers by lining the chambers with refractory, which radiates and reflects heat back into the fuel layer. The refractory also protects the walls and base of the chambers from the high temperatures in the combustion zone.

Where agricultural-based straw is the primary bio-fuel, silica and potassium debris settles in the removable tray at the bottom of the secondary combustion chamber. This requires a periodic manual cleanout.

Heat Exchanger

The extremely hot gases from the secondary chamber flow to the heat exchanger which is a fire-tube boiler. A hydronic system delivers this heat to desired locations and supplies precise heat for any public, commercial, residential or agricultural building. Fly ash can be moved by combustion gas flow and can deposit on the heat exchange surfaces in the boiler. This ash is removed regularly to maintain good heat transfer performance. Tube cleaners are in place to automatically clean the boiler tubes and collect the fly ash in the particulate collection system.

Exhaust System

An induced-draft exhaust system completes the combustion process. The induced-draft system uses a large blower located in front of the stack which sucks the exhaust gases out of the boiler and forces them up the stack. The draft of this fan is regulated in relation to the combustion air to maintain a very slight negative pressure in the combustion chambers so that gas flow is continuous and that no combustion gas leaks occur.

Instrumentation

Instrumentation and Automation Control is important for efficient operation in response to energy demand and safety. The complete feed and gasification process requires a complex control system using computers and micro-processors to match heat delivery with demand. A key task of the control system is determining the rate at which fuel and air are fed to the primary combustion chamber to ensure gasification, and the rate at which air is fed into the secondary chamber of ensure efficient combustion. Control is achieved when fuel and air are automatically modulated simultaneously to maintain the correct ratio under high or low demand. Start-up and shutdown sequences are programmed, and alarms will sound in upset conditions. Remote monitoring is available.

System Requirements

• Electrical power (3 phase system preferred, single-phase possible)
• Air requirement (compressor 100-120 PSI, 7-10 CSF)
• Cold water source (50-70 PSI, 2-4 gallons/minute)
• Concrete floor and building structure (brick or metal)
• Shelter (or building structure) to cover the disintegration and conveyor system
• Ash bin (to contain ashes being removed from the gasifier primary chamber)

System Maintenance

ZeroE Energy heating system requires little maintenance and management. Tasks such as ash disposal, general cleanup (usually in the fuel storage and handling area), checking heat exchanger water levels, checking the fuel delivery system for oversized material build-up, plus monitoring primary and secondary combustion chamber temperatures, along with stack temperature are done daily. The computer system will signal the operator in upset conditions or for out-of-range readings.

Maintenance

In addition, there are regular maintenance tasks that need to be carried out periodically. These include:

• replenish the depleted fuel supply
• lubricate mechanical components
• inspect and adjust chains, gearboxes, blowers, etc.
• remove silica from the secondary chamber
• remove debris from the heat exchange
• inspect refractory and repair as necessary
• test safety devices

Most of the routine maintenance can be carried out by the system operator or by the general on-site maintenance staff. It is recommended that the system be inspected by a ZeroE service technician annually.

System Life Expectancy

ZeroE systems can last indefinitely since the components will be replaced as they wear out or deteriorate. In the forest industry, wood combustion systems have been in operation for over 50 years. In practice, 15 to 20 years is used as a reasonable life expectancy for a biomass combustion system in life-cycle costing.

Emissions

Dillon Consulting Limited was retained to conduct source testing on the gasifier exhaust stack to quantify combustion gas emissions. These tests were conducted on our 3 million btu/hr gasifier operating at the maximum system designed production rate of approximately 500 pounds (227 kg) of straw feedstock per hour.

The following gases were measured from the exhaust gas stream:

• Oxygen
• Carbon Monoxide
• Sulphur Dioxide
• Oxides of Nitrogen
• Carbon Dioxide

The following table summarizes the results of the combustion gas concentrations in the gasifier exhaust stream.

Combustion Gas concentrations are the average concentrations from 3 separate test periods.

“The results of the dispersion model indicate that the emissions of all of the measured parameters from the TGE3000 Gasifier comply with the Ontario and Manitoba regulated Point of Impingement and Ambient Air Quality Criteria Concentrations. The POI concentrations for the remaining combustion gases do not exceed any of the regulated POI limits or AAQC. In general, the POI concentrations predicted by the dispersion modelling for all measured pollutants are at least one-half of the regulated levels with no pollution control devices.”

– Dillon Final Report, March 2003

Ash Analysis

ASH PRIMARY #1

ASH SECONDARY #1

Independent Lab Analysis

Chicken Manure

If you are spending $96,000 per year on propane to heat your facility, by switching to straw heat you would only spend $16,000 and save $80,000 per year!

Biochar

A valued by-product from our ZeroE Series of BioHeat systems

Along with bags of potting soil, mulch, and compost, you soon may see bags of biochar for sale at your local nursery.

To explain what biochar is, we need to return to the Amazon basin circa 450 a.d. Indigenous people didn’t practice slash-and-burn farming as they do now. They practised slash-and-char agriculture, roasting wood and leafy greens in “smothered” fires, in which lower temperatures and oxygen levels resulted in the production of charcoal instead of ash. The charcoal was buried in fields where crops were grown.

But then, with the arrival of Europeans and their diseases, the Amazon civilizations, some with cities of more than 100,000 people, collapsed. Slash-and-char agriculture was forgotten, as were the fields of buried charcoal. But they weren’t gone. In the 20th century, huge expanses of black soil were rediscovered, although at first, no one knew what they were. Then, in the 1990s, scientists determined that these soils were manmade. They were dubbed terra preta (“dark earth” in Portuguese). And they were extensive. Some estimates put the total acreage covered by the charcoal-enriched soil at twice the size of Great Britain.

Most amazingly, the soils extended up to 6 feet deep in many places. Scientists have theorized that terra preta soils are self-propagating and have grown in depth since they were first made. The charcoal, acting a lot like humans, had been colonized by myriad microbes, fungi, earthworms, and other creatures; these soil organisms produced carbon-based molecules that stuck to the charcoal, gradually increasing the soil’s carbon content. Carbon in decomposing plants, which would otherwise escape into the air as greenhouse gases, was sequestered by the biologically active charcoal in the soil. Scientists theorize that the charcoal was originally laid down in thin layers and that earthworms chewed through the layers and mixed them deeply into the soil.

That is just the beginning of the benefits of this strange soil. It appears that the carbon will be sequestered for a thousand—possibly thousands—of years, unable to contribute to global warming in the form of greenhouse gases. Green charcoal, or biochar made from agricultural residues or renewable biomass, appears to hold the most promise as a carbon sink. Every ton of this biochar in the soil is capable of capturing and holding at least 3 tons of carbon.

Biochar also stimulates mycorrhizal fungi—those fungal symbionts that live on plant roots, scour surrounding soil for hard-to-find phosphorus and deliver it back to their host plants. According to scientists studying the soils, microbial growth of all kinds is substantially improved. And so is the soil’s ability to hold nutrients until plants need them, then dole them out at the optimum rate for plant health. Crops have been shown to grow 45 per cent greater biomass on unfertilized terra preta soil versus poor soil fertilized with chemical fertilizers.

Research on biochar is underway at universities around the world, and agribusiness is beginning to show interest. While biochar could be manufactured by cutting down forests and fields, a more sensible approach would be to utilize the billions of tons of organic waste that now goes into landfills—a perfect raw material for biochar.