An Alternative Heating Option for Boiler Producers
The poultry industry has seen some drastic increases in energy prices, both in electricity and heating fuels - gas, woodchip, wood pellets and kerosene. These costs were not covered initially by price increases by the market. These price increases drove the entire sector to look at alternative energy sources. For alternative heat options, biomass is one option, and using the litter produced on farm is another.
To investigate this further, Rebecca Tierney, Teagasc Poultry adviser, spoke with Jack O'Connor, Jack is the founder of BHSL Waste Solutions. Jack gave an overview of his product.
Background and How the Product works
BHSL is the company he founded back in 2004. Before that he had been researching on his poultry farm in West Limerick, around the ideas of finding alternative uses for chicken manure as spreading had become incredibly difficult since the mid-90s with European Regulations around leakage into rivers, etc.
The technology he chose was called FBC, Fluidized Bed Combustion. It was a well-known technology in large power plants for dealing with material like manures that have high ash and have varied moisture. He wanted to see if they could reduce it to be able to use it in a size suitable to what they can use on the farm and that's really where it started.
There was a lot of issues - technical, financial and regulatory. Manure was classified as waste back then, so they took the case to the Department of Agriculture, Food and the Marine (DAFM) and the Environmental Protection Agency (EPA). From there, with their support, they headed for Brussels and in 2014, Brussels agreed that chicken manure wasn't waste in the manner that they were proposing to use it. So the rules - 592/2014, now say poultry farmers can now use their manure as a fuel on their farm. It's not classed as waste anymore, it is classified as an animal by-product to be used as fuel and combustion. There's guidelines and regulations surrounding that.
They then developed the technology on their own farm first and then on a number of farms locally in West Limerick and one farm down in Kinsale. This resulted in attracting UK customers. The idea was very attractive, rather than trying to find a home for the manure, you stored it in a secure shed. The manure was then automatically fed with a top loader handling system. This is a rake that travels on a carriage above the stock pile. It drags the manure onto the conveyor belt which is fed into the boiler.
The boiler consists of a bubbling bed of sand, the sand bubbles to a height of approximately 300 or 400 centimeters. Inside that bubbling bed of sand, it reaches a temperature of 700 degrees by an auxiliary burner, either diesel or gas burner.
Once the sand has reached the required temperature of 700 or 800 degrees, the manure is dropped in. Then the manure starts combusting in the bubbling bed of sand. The sand evaporates any moisture that's there and allows the carbon-oxygen reaction to take place. It can reach temperatures of up to 930 degrees in the upper section of the boiler, called the free boat. The gases are then pulled through tubes and in the tubes there is water. The water is then heated to 90 degrees and it's pumped down to the chicken sheds into radiators. So you have now hot water radiators spread around the shed. The gases in the boiler continue on through a bag filtering system. Typically you won't see any plume or anything from the stack because the bag filter is that efficient to take all the ash and dust particulate.
It's manufactured in Kantoher, West Limerick, they have 500 kilowatt unit base at their base, which they try lots of different materials. The UK has been a huge market for them since 2011. There has been over 22 units put on farms there, both on poultry manure and hen manure.
It's success really has been around the fact manure has replaced the need for gas. That is a huge cost saving. The ash is sold for £140 to £150 a ton because the ash is full of all those nutrients that were in the manure in the first case, P, K, and trace elements.
The big reason that they are in the UK is the renewable heat incentive, the RHI. It was very lucrative as farmers as farmers got paid for every kilowatt of heat that they generated from manure. For 20 years it guranteed that those kilowatts would be rewarded by that government incentive. There is a fast payback due to the RHI.
Is Lower Financial Success of SSRH Compared to RHI Affecting it's Uptake?
The technology is proven, the regulation is there, DAFM and the EPA really have endorsed and supported what they do. They have done all they can to help with the regulatory side of this technology. It's very obvious that this is a sensible thing to do rather than trucking the manure around from A to B to C from a biosecurity point of view, environmental, carbon footprint and everything else. It's putting the manure in a sealed shed and we want to emphasis sealed shed.
It is taken at the end of the cycle, after five or six weeks, and it's put in the shed. The air from that shed is the primary air source for the boiler. There's negative pressure in the shed the means there is no smells or odours in the yard. It also means there is no chance for bacteria escape onto the farm, which could be a sensitive issue. They now have well over 10 years on these farms confirming that this can be a safe, biosecure way of dealing with them rather than trucking it from poultry units to tillage farms or elsewhere.
In terms of the license that is required, Jack mentioned the regulation that says manure from their farm is not a waste, but rather a byproduct. Is an EPA license or any particular type of license required to have a Biomass boiler burning litter?
The competent authority here is now DAFM, so people will have to apply to DAFM for animal by-product regulation 592/2014; which is an application for a unit to use the manure as fuel on the farm. The department will go through the processes there. They will check the biosecurity, the storage, etc. making sure they have all things in order, safe, clean and then you must ensure that their temperatures are 852 seconds. You must ensure that the ash is stored in the place. You must ensure the manure is in a sealed room or container. You must show you have the ability to maintain temperatures continuously. And if you don't, if your temperatures drop below the 852 seconds that your machine automatically responds and cuts out so that it's not burning manure at a lower temperature against the regulations. That's the department side.
On the EPA side, you will apply to the EPA for a note on the IED license to say that there's an animal byproduct operation on the farm and that's noted by the agency. The management of the boiler and any inspections, is the responsibility of the DAFM.
Is there a Cost to Applying for that License? Does That have to be Renewed or Updated?
It's just a case of applying to the animal byproduct section of DAFM. There is a yearly inspection on your emissions. You must show you employ the services of an independent testing company to test the emissions to ensure they're all in order. DAFM can have an unannounced inspection aswell.
Can the SSRH be applied for it while using the poultry manure as the fuel source?
Yes, They have cleared with the SEAI from the outset because it's not a waste, it's a byproduct, so it does qualify for the SSRH.
This Method is being used quite a bit over in the UK. Is this all Boiler Farms? Has it been used on Turkey farms, pullet rearing and other farms?
On egg producing farms, hen manure doesn't have the same calorific value as poultry manure. Poultry manure is so valuable because a 5 week chicken is not digesting all of the high protein diet that they're eating. So alot of the manure will contain that undigested protein that has been excreted. Therefore, the calorific value of poultry manure is close to what of wood chip. It is 12-13 mega joules a kilogram dry manure. Not dry, but 35-40%.
There isn't the same amount of protein fed to egg producing hens. There's alot of calcium in there, so the energy value drops down to approximately 6-8 mega joules per kilogram, which is low. Jack has shown that they can use it as fuel as well. There is 4 machines operating on hen manure; while the other 18 operate on poultry manure.
What Moisture Content Does Poultry Manure need to achieve to Produce the Heat that's required?
Typically, anything from 35-45% is good. 35% is a sweet place . 30-40% is a good place to be. Now the reason the FBC technology was chosen is that it can take huge variations in moisture content, anything from 25 - 50.
If the material has a higher moisture content, then you're paying the price for it because it needs more manure in to the boiler to get the same kilowatt output.
How Much Litter is Required?
It's typically around 1 ton of manure per day to give you 100 kilowatt. That's for 24/7 operations, so 500 kilowatt unit will take 5 ton. Most farms in Ireland will be 300 kilowatt so that's 3 ton per day.
There's sufficient litter on farm to cover the requirement. The SSRH refers back to historical gas usage, but we argue that historical gas usage is impeded by the fact that it costs so much that your gas will be turned off as you possibly can because of the cost. Whereas when the fuel is available is will be used. Therefore, you get abudant heat. This will mean having water heaters on the shed at 3 and 4 weeks. You're creating a better ventilation and better environment. This improves the manure quality, therefore improving fuel quality for the next batch.
Obviously, the biggest emitter that causes planning issues is ammonia, and ammonia is moisture and nitrogen coming together. Where you have less moisture, then your ammonia is automatically reduced. We are using indirect heating, which is a hot water radiator, we have reduced water. CO2 and the dryness has reduced the ammonia output from it.