Fitting WTE in with Recycling
The State of Indiana is looking to update environmental legislation concerning the definition of recycling. The initial proposal may include waste-to-energy in the list of acceptable recycling technologies.
There was much opposition to this, people wanted to see waste-to-energy removed from the list of acceptable recycling options.
WTE vs. Recycling
While WTE is certain not the same as traditional material recycling methods, it is a form of recycling in that it recovers the energy from the waste which would otherwise be wasted when the waste is landfilled. It seems appealing to try to recycle everything, but sometimes that is not an environmentally-sensible solution. Many wastes would require more energy and resources to recycle than to remanufacture. These wastes are best dealt with using waste-to-energy technologies, including incineration. Is it more environmentally-sound to burn diesel fuel hauling the materials around for recycling, or incinerating them locally for energy production? It all depends on the materials, the processing they require, and the hauling distance.
To maximize recycling, one thing that can be done is that manufacturers can package their goods in recyclable containers, such as corrugated boxes and PETE instead of PVC plastic. PVC is nothing but trouble anyways, producing chloride that corrodes the furnaces and boilers of incinerators and forms extra dioxins under poor combustion conditions.
Efficient Incineration
If new incinerators are built, they should not be of the "electricity-only" variety because these units waste about 80% of the total energy input. It makes sense to site incinerators in urban areas where the waste is generated and a district heat demand is located. A mid-sized incinerator will simply throw away over 100 megawatts of heating power - heat that could be used. A waste-to-energy cogeneration plant with flue gas condensers can recover up to 98% of the energy from the waste it burns. Up to about 30% of that comes out as electricity, the rest as heat. This heat is usable as heat or it can be converted into chilled water using an absorbtion chiller, reducing strain on the grid in summer due to air conditioning load.
Waste Heirarchy
Rather that placing WTE on the same level as material recycling, it should be placed below recycling in a waste management heirarchy. Waste that is suitable for recycling is recycled, what cannot be recycled is processed using WTE.
» Read full article from Fort Wayne, Indiana
C&D Debris Incineration in Maine
Bangor Daily News reports that an increase in the use of construction and demolition waste is favored for use as fuel in the state's biomass and waste-to-energy facilities.
C&D (construction and demolition) waste contains wood which is useful as fuel, but also contains other substances including but not limited to lots of PVC (vinyl siding, flooring, wallpaper, pipe, jacketed electrical cable, deck and fence materials, and packaging). The wood makes good fuel - but just about everything else in C&D waste is terrible fuel. Asphalt shingles will burn nicely, as long as they are mixed with a great deal of biomass in a WTE facility designed to combust municipal solid waste (better pollution control equipment than a basic biomass boiler; those crude oil refining residues are probably chock full of sulfur)
One of Maine's issues is with the importation of out-of-state C&D wastes. Haulers bring mixed waste in to be burnt, then when they get to the power plant the wood is burnt and the remainder must be landfilled. Legislators hope to enacte regulations to allow only WOOD to be accepted into the state for incineration.
Turning Waste into Energy beats Landfilling
Christopher Hume of the Hamilton Spectator delves further into Toronto's ongoing debate about what to do with the city's waste when Michigan stops accepting Toroto's trash for deposition in their landfills. Hume argues that waste-to-energy beats landfilling hands-down as the most sustainable disposal solution.
» Read More at Hamilton Spectator
Incineration inferior to waste diversion
Barry Friesen of the Hamilton Spectator argues that careful consideration should be made before building waste-to-energy plants.
I agree. Incineration is third on the waste management hierarchy, after waste reduction and recycling/composting. WTE should not be installed as a replacement for material recycling; WTE is designed to complement recycling programs because not all waste is feasible to recycle. That is where a fine line forms. What is feasible to recycle differs in many people's minds. Plastic bottles, for some time, were often not considered to be worth recycling because the manufacture of the plastic is quite energy-efficient and the petroleum feedstocks that make up the plastic itself were quite cheap. Transporting and collecting airy, light plastic bottles was not considered to be worth the cost. Incineration of these bottles yields a great deal of energy. Nowadays, bottle recycling is much more cost-effective and the highly-refined plastic is more valuable for its material content than its energy content.
Incineration of other plastic items, such as wrappers, bags, and miscellaneous containers, probably is more energy-efficient than recycling if the plastic is burned at a combined heat and power facility.
Metal and glass obviously are better off in the recycling stream. They don't burn! Incineration can, however, aid in the recovery of metals. Some waste (such as the Asian food takeout containers) has small metal handles and parts. In the WTE plant, the paper would burn up and the steel would be left for later collection.
It is more difficult to justify the combustion of waste in North American incinerators than in European ones because NA units tend to be electricity-only, and they are only about 20% efficient at converting the heat into electricity due to restrictions on the steam temperature that can be made in incinerators. Temps higher than about 800F in the boiler will lead to corrosion on the furnace-side walls of the boiler tubes. This corrosion is due to the high chlorine content (bleached paper, PVC, salt) of waste compared to fossil fuels. Adding heat recovery to the plant can boost efficiency to well over 85%, but to recover heat the plant needs to be located in the city.
As for the question of putting Waste-to-energy plants in our cities, I would have no problem living next to one. Other people may be more resistant.
When new facilities are proposed, there is always concern that the high capital costs of the plant that need to be paid off will encourage the production of waste to keep the ovens fired up and the electricity flowing. Building a plant with several smaller burners instead of one large one would allow it to run at reduced capacity if for some reason waste production fell off or recycling rates went up. The waste could also be co-fired with biomass fuel.
Ideally, Waste-to-Energy should come after source reduction, reuse, and sensible recycling (meaning don't try recycling every last cigarette butt, gum wrapper, and bottle cap because it takes more resources that it is worth).
WTE vs. Landfill in Tulsa
In Tulsa, Oklahoma, everyone is talking trash.
There are debates in Tulsa concerning what to do with the city's trash. Most of it is currently incinerated at the W.B. Hall Resource Recovery Facility, and the resulting heat is sold to Sunoco for refinery use, ofsetting the use of OIL for making steam. The cost of landfilling trash compared with the cost of incinerating it is much lower (obviously, this is in Oklahoma, not New England! ). Tulsa residents are not happy with having to pay higher trash disposal rates than surrounding areas.
Landfill, or incinerate? You should continue to burn that trash...because the energy output of the Hall RRF is going to the oil refinery, where it is directly replacing the combustion of petroleum products. This offsets greenhouse gas emissions and it reduces the burning of oil products to make steam, which means there will be more oil to be turned into gasoline to drive our beloved cars, distillate to heat our homes, propane to fire up our barbeques, etc. In this case the WTE facility really does reduce our reliance on foreign oil, unlike electricity-only incinerators where they replace coal - meaning better environmental performance but coal is a domestic resource.
Is $15 too much to pay per month to have your trash hauled away? I think that is pretty darn cheap! Trash is the consequence of our resource-guzzling consumer society and we have to either deal with it responsibly (reuse, compost, recycling, WTE), or stop its production (source reduction).
