WHAT'S A BIOMASS SOURCE? AND HOW COME IT MATTERS IN OTTAWA?
This story is brought to you in part by Biomass Recycle
Bioenergy is a renewable energy resource derived from living organisms and/or their byproducts. It currently accounts for approximately 6% of Canada's total energy supply. Bioenergy is an extensive sustainable energy resource that can supply energy to Canada while emitting low CO2 and reducing waste. Scientists and engineers at CanmetENERGY are at the forefront of innovative technology developments that will enhance the sustainability of bioenergy for Canada's future.
Specifications and test methods for characterisation of solid biofuels are essential to the consistency and performance. Agreed upon standardization criteria give confidence to the suppliers, consumers and regulators. It also allows heating equipment manufacturers to design and engineer their systems to match the fuel specifications.
Public Services and Procurement Canada has chosen to work with CanmetENEREGy to conduct tests on two biomass source materials, woodchips and biofuels, with a view to determining which low-emission fuel would be most approrpiate fo the National Capital Energy Systems.
WaterToday spoke with Sebnem Madrali, CanmetENERgY Engineering Projects Leader. An abridged transcription of thsiat conversation can be found below.
WaterToday - I've done a series of articles with the federal government on replacing the heating and cooling plants for the Ottawa 80-building National Capital Energy Systems. And my understanding is that Public Works is testing two different bio systems for use in those plants; one based on woodchips and the other on biofuels. Is that about right?
Madrali - That's my understanding as well; yes.
WaterToday - Could you frame what you're up to for our readers?
Madrali - I'll give you a little bit of background first in terms of how we got involved with this project and what Public Works is looking for in terms of guidance.
When Public Works initiated this project some time ago, they did a lot of homework; talking to people and trying to get a better understanding of what the heating system would look like and what type of fuels sourced from biomass material might be available. And when they were ready to move on, they reached out to other government departments to gather some of the technical expertise they could use and get advice as to how best to go forward.
It was at that point that we got involved, as CanmetEnergy, which is part of Natural Resources Canada; we are a research group within NRCan. What we typically do is use different fuel sources and advance the conversion technologies for those fuel sources to heat, power, fuels and chemicals.
More specifically our expertise has been focussed on the thermochemical as it relates to combustion, pyrolysis (thermochemical decomposition of organic material at elevated temperatures) and gasification. All three are part of the thermochemical conversion process, which means that there is some heat involved in the process and there are some chemical changes happening to the material.
As a result, there is either a fuel product or energy generated. And the energy generated from that process could be in the form of thermal energy, steam or heat, or in the form of a fuel product that could be used later.
In other words, the heat energy or thermal energy can then be used as electricity generation or power generation, and in the case of gasification or pyrolysis, the conversion can be used as an intermediate product - whether liquid fuel or the gaseous fuel - which can be used again for heat or electricity generation after further processing. We do quite a lot of work within the realm of those conversion processes to determine the optimum conditions for those processes; and how biomass reacts within those processes.
WaterToday - Could you just pretend I'm in grade six and explain what specific tests you are doing for this plan?
Madrali - In the context of the Public Work project, our role is essentially to provide technical advice to make sure that the choices they make on biomass fuels are proper; and meet certain fuel specifications.
So I'll give a little bit of background. First, I would like to make a differentiation between biomass and bio fuels. We're working hard within our organization as well as with other stakeholders to bring specifications and standards for biomass fuels that could be comparable to more conventional fuels like natural gas or fuel oil.
In the past, it was thought that if you were putting biomass material into your furnace you were suddenly turning it into fuel. But it's not that straightforward. Unless you're careful to meet certain specifications you're not going to get the best out of your system, in terms of conversion, efficiency and emissions.
So as an organization, - and it is also my particular interest in this research – we are bringing biomass fuel standards to Canada.
When making biomass fuels, especially solid biomass fuels, what you're starting with is a material originated from biomass material. And that could be woody biomass; it could come from the agricultural sector and that could be from grass types. It has a wide range of origins and sources.
WaterToday - Just to be clear then, you're not doing anything on site in these heating/cooling plants, you're at Canmet doing thermal tests?
Madrali - Our work essentially relates to biomass thermal conversion and defining the biomass fuel specification and standards that will give the best results.
With Public Works, our role is to make sure that the biomass fuel they choose for the National Capital project, is the proper one. It needs certain fuel specifications so that when it's being run on, and operated on, the unit it will perform properly.
WaterToday - I presume the specifications are different depending on whether you are dealing with woodchips or bio fuels as a biomass source. Can you elaborate on this?
Madrali - Ok, so one project is going to be based on woodchips and for the other project, the boiler is going to be fueled by liquid fuel that is being generated through a pyrolysis process.
Now, pyrolysis oil is a relatively new fuel type. And there aren't many players in the world that generate/ produce pyrolysis oil as a fuel. We in Canada have several companies working on this. And at this moment, my understanding is that Ensyn is one of the few who produces commercial scale pyrolysis oil meeting fuel specifications as established by ASTM (ASTM International - Standards Worldwide)
WaterToday - And so these people are somewhere doing this process; turning this into fuel?
Madrali - Ensyn has a plant in Renfrew Ontario.
WaterToday - Oh okay. That's very close to Ottawa
Madrali - Yes, and right now, that plant is producing enough fuel oil or pyrolysis oil to provide some of that material to a couple of projects in the US for heating purposes.
WaterToday - Oh really!
Madrali - Yeah. So it's new to Canada but this is definitely being used in the US. I believe there are four installations that have been using pyrolysis fuel for their heating purposes. And in Maine, Bates College, is in the process of switching to pyrolysis oil.
WaterToday - Okay so for the other test based on woodchips, what is the process? I have this idea in my mind of train cars full of wet chips waiting to be dumped in Ottawa, is this accurate?
Madrali - I think there are several things that I need to tackle to answer your question. First of all, you're assuming that this is going to be wet material. Yet, for any fuel to be a good fuel, controlling moisture content as well as ash content is very important. When we started our project in Canada, one of our first tasks was to bring fuel specifications and standards from ISO and have them adopted in Canada by the Canadian Standard Organization (CSA). What those ISO specifications and standards define is limitations on moisture and ash content, as well as the particle size of the material, whether its woodchips or pellets .
There is a full range of other characteristics that needs to meet certain requirements, depending on the grade of the woodchips or the pellet. For Public Works' purposes, we looked at the existing fuel standards for the woodchips and we have adopted certain parameters from there.
And I believe that we have limited the moisture content to 40% on wet basis. Typically, greenwood as soon as it's harvested, has somewhere between 55% and 60% of moisture content.
WaterToday - Ok, I'm with you so far.
Madrali - So what we are basically saying is that the woodchips cannot be totally green and we have put a maximum moisture content limitation on the woodchip. We've also specified the particle size of the woodchips.
WaterToday - Why is that?
Madrali - Typically, one of the difficulties we have in Canada is that the woodchip definition varies depending on who you are talking to and tends to mean different things to different people. So, to make sure that the woodchips being delivered meet certain criteria, we define them, and the important parameters are ash content, moisture content, and particle size distribution.
So we put a maximum limit of moisture content of 40% and a amximum limit of ash content of no more than 3% on dry basis.
We also determined a particle size distribution on the woodchips delivered. We don't accept any material that is going to be long and stringy and would create heating problems. In other words, the particle shape as well as its size must meet certain requirements. To moitor this, not only the project manager but also the operator of the boilers is going to be making sure that each delivery truck is being checked and confirmed to meet the requirements. Random checks by Public Works will also be part of the quality assurance process that is being put in place.
WaterToday - One final question, before I let you go, do you think it's realistic for us to say, “Okay no more GHG in ten years from any of our power plants”? Do you think anything like that's even realistic?
Madrali - In my personal view, and you have to put that in the context of my expertise, and the last 15 years of work I've been doing to promote biomass as a renewable energy, contributing to the energy mix in Canada. And so far In Canada, we have been doing a relatively good job of it. The wood residues generated by the forest industry have been used extensively for steam generation and electricity generation at pulp and paper mills.
WaterToday - Right.
Madrali - But what we are beginning to see is institutions, commercial buildings like hospitals, schools, senior complexes and some district heating systems, showing more and more interest in renewable energy. Granted, the options that are available to them depend on their locations and what fuel types are available to them.
For instance, they might be on the natural gas pipe line and given that current natural gas prices are pretty low, they may just choose to switch from fuel oil to gas. But if they are thinking of getting into more renewable energy. then they'll be considering solar, wind and biomass.
So, I believe there is a potential under certain conditions for biomass to be used for heating and hot water purposes, particularly in the commercial and institutional sector.
So that's one thing. The other thing that is going to be potentially big for us is that there is a lot of interest in research and development for net zero buildings.
What that is moving towards is making sure that all the energy efficiencies in the buildings are being met.
The installations, the windows in the new buildings are going to be at such strict standard that the energy requirement are going to be pretty minimal. And I could see some of the small-scale installations for solar, especially solar and biomass being integrated, and introduced to these buildings towards that net energy. They could play a pretty important role.
This story is brought to you in part by EVOTO - EV Car Rental