Basel convention / TDF p. 1 Ms. Julie Croteau International Waste

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Ms. Julie Croteau
International Waste Programs
Waste Reduction and Management
Environment Canada
70 Cremazie
Gatineau, QC
K1A 0H3
January 18, 2008
Dear Ms. Croteau,
Re.: Basel Convention: Draft Proposed Revised Technical Guidelines on Environmentally Sound
Management of Used Tires
UNEP/CHW/OEWG/6/INF/6
The Cement Association of Canada (CAC) appreciates an opportunity to comment on the above noted
revised draft document prepared by Brazil for the open-ended Working Group on Basel Convention on
the “Control of Transboundary Movements of Hazardous Wastes and Their Disposal”. Let us state right
at the outset that after a thorough review by the CAC and its members we have determined this to be an
extremely biased one-sided document written with only one and only one purpose: to prevent the import
of rethreaded tires into Brazil. Any of the widely practiced solutions of handling, recycling and reusing
used tires are therefore viewed negatively, without proposing any alternatives.
The CAC and its members do not feel that we are in a position to comment on this proposed draft
document in its entirety, but would like to provide you with some initial thoughts and arguments
concerning a section on ‘Co-processing in the Cement Industry’, where we have some expertise.
Scrap tires, if not properly managed, can create an environmental nuisance and eyesore. What’s more,
they can constitute an environmental hazard if they burn in an uncontrolled manner, such as in a field or
landfill. However, by utilizing cement kilns’ controlled combustion environment, their high processing
temperature – 1,450oC with the flame temperature up to 2,000oC – scrap tires can be an environmentallysound source of energy in the manufacture of cement.
Let us first comment on the use of tire-derived fuel (TDF) in Canada, the U.S.A. and European Union
countries, the jurisdictions with the most advanced environmental controls and permitting processes.
Canada
In Canada, nine (9) of the sixteen (16) cement plants of the CAC member companies have a permit to
use tire-derived fuel as a part of their fuel mix. To include TDF, or any alternative fuels, the respective
plants undertook rigorous environmental tests to assure the permitting authorities and the local
communities that by including TDF no statistically significant increases in emissions releases would
occur, to endanger either the health of the surrounding communities or the environment. All the
Canadian cement plants using TDF are operating well within their operating limits, and some provincial
jurisdictions, such as Quebec, encourage the cement industry to use TDF in order to divert the scrap tires
from landfills. CAC statistics show that in 2004, the Canadian cement industry utilized 41,992 tonnes of
TDF, i.e. 1,092 TJ out of the total 53,456 TJ fuels used. Thus TDF represents 2.04% of the industry
thermal energy supply, a small but growing amount of alternative energy.
Basel convention / TDF
p. 2
Recent NRCan’s CANMET Materials Technology Laboratory study on ‘Scrap Tire Recycling in Canada’
reports that about 20% of all scrap tires generated in Canada are used as TDF, mostly in cement kilns
and in one paper mill. This equals about 6 million tires, approximately 49,000 tonnes, beneficially reused.
The study states that due to its high calorific value, TDF is a good substitute for fossil fuels. According to
the study, in 2003/2004, 18.85% (5,344 t) of recycled scrap tires in British Columbia were used as a TDF,
12.24% (1,505 t) in Manitoba, 24.00% (13,172 t) in Quebec, and in Ontario 30% (30,520 t), mainly
exported as TDF to the USA. [Source: ‘Scrap Tire Recycling in Canada’, A. Pehlken, E. Essadiqui,
NRCan, CANMET Materials Technology Laboratory, MTL 2005-08(CF)]
Specifically, on the issue of the dioxins and furan emissions from cement kilns, it should be noted that the
CCME 2004 Report on “Status of Activities Related to Dioxins and Furans Canada-wide Standards”
(October 2004) states that:
“Available test data from the cement sector (note: regardless of fuels used) indicate releases of dioxins
and furans from cement kilns are below 80 pg/m 3, with one exception. To date, 80 pg/m 3 is the lowest
emission limit established by a Canada-Wide Standard (CWS) based on available technology and
feasibility.”
Based on this, CCME decided not to develop a CWS for dioxins and furans emissions from the cement
kilns.
U.S.A.
In the U.S.A., the number of cement plants utilizing scrap tires as a supplemental fuel has risen sharply
over the last 15 years. As of 2004, state and local environmental agencies have approved the use of
TDF at 43 plants in 22 states. Fifteen additional facilities in 14 sates have expressed interest in obtaining
a permit but have not begun utilizing scrap tires as a fuel (as of 2004). The delay in utilizing TDF may be
due to equipment limitations at the cement plant, regional TDF availability, state regulatory agency
review, and local community discussions.
A quote from the U.S. EPA530-F-006, April 2005:
“The EPA supports the highest and best practical use of scrap tires. In 2003, more than 290 million scrap
tires were generated in the U.S. Nearly 100 million of these tires were recycled into new products and
130 million were reused as tire-derived fuel (TDF). Based on over 15 years of experience with more than
80 individual facilities, U.S. EPA recognizes that the use of TDF is a viable alternative to the use of fossil
fuels. EPA testing shows that TDF has a higher heating value than coal. The U.S. EPA supports the
responsible use of tires in Portland cement kilns and other industrial facilities.”
Furthermore, the U.S. EPA states that “EPA and state testing has shown that TDF produces emissions
comparable to other conventional fuels. At well controlled facilities, emissions will not change significantly
when TDF is used to replace some of the typical fuel used at that facility. TDF can be used successfully
as a 10-20% supplementary fuel in properly designed fuel combustors with good combustion controls.”
Addressing specifically dioxin / furans emissions, it says “EPA has previously determined that the type of
fuel used, coal vs. alternative fuels, likely does not affect dioxin/furan emission rates. Regardless of the
fuel used, cement kilns must comply with stringent limits on dioxin/furan emissions (0.2 ng TEQ/dscm)”.
Europe
Looking for a comparison to Europe that perhaps more than any other part of the world actively pursues
an option for replacing some of the fossil fuels with alternative and biomass fuels, of approximately 2.7
million tonnes of scrap tires handled annually there, 27% are directed to energy recovery systems
including cement kilns [EARI]. In 2004, according to CEMBUREAU, alternative fuels (AF), at 126,759 TJ,
represented 18.2% of the total cement industry fuel supply. Tire-derived fuel at 21,879 TJ constituted
over to 17% of the alternative fuels used by the cement industry in Europe, i.e. over 3% of the total
cement industry thermal energy supply. Only animal bone and meal (at over 19%) represented a higher
share of the AF used in Europe.
Basel convention / TDF
p. 3
Japan
In Japan, there were 103 million scrap tires processed in 2003 with 23% of them being used as a fuel in
the cement industry. For that year Japan recycled 44% of all scrap tires through heat utilization [JATMA
2004].
Can all of these environmentally conscientious jurisdictions be wrong?
NOx emissions
Even the draft Basel Convention document, albeit rather grudgingly, admits the positive effect of TDF use
in cement manufacturing on its nitrogen oxide (NO x) emissions. Cement manufacturers have known for
quite some time that through staged combustion of fuel, such as scrap tires, NO x can be reduced up to
30% depending on the kiln type, age, fuel combustion location, and the plant’s ability to optimize the
manufacturing process. An U.S.EPA-sponsored study on NOx reductions reported that TDF added to the
raw materials feed end of some preheater or precalciner kilns can reduce NO x emissions by over 30%,
and it also found that when mid-kiln injection of scrap tires was used, there was an average NO x reduction
of 33% to 40% for selected long dry and wet kilns, respectively [U.S.EPA “NO x Control Technologies for
the Cement Industry”, 2000].
International Energy Agency (IEA) Study
IEA (International Energy Agency) Coal Research, in its 2003 report “Co-utilization of coal and other fuels
in cement kilns” [IEA Clean Coal Centre CCC/71], shows results from a study of nine long kilns equipped
for mid-kiln firing of tires. NOx reduction between 11% and 55% was reported, with an average drop in
emissions of 31.5%.
The same IEA study also addresses other cement kilns emissions, such as minor and trace elements
(Heavy metals) and dioxins and furans, and the effect of fuel substitution with alternative fuels. Trace
element emissions are released from the clinker production process according to their volatility, much as
they are from power stations. Most of the heavy metals come from the cement raw materials, and their
reduction in the raw materials is virtually impossible. Hence alternative raw materials and fuels should be
selected so as to avoid further enrichment in the clinker mix. Tires contain low concentrations of
halogens, but zinc is enhanced in tires. This can limit the rate of substitution for the primary fuel for
technical but not environmental reasons. Typically, TDF substitution is limited up to 20% of the total kiln
fuel supply. The IEA study notes that a review of stack tests at US cement kilns using some TDF
substitution showed that zinc emissions increased and mercury emissions decreased. Emissions of other
metals decreased or remained the same. IEA notes “Zinc is not of environmental concern and is not
therefore regulated in the USA.” An example is cited of 1991 tests on a kiln with 20% TDF substitution,
with resulting decreased emissions of arsenic, cadmium, nickel, zinc, and hexavalent chromium, while
lead and mercury emissions increased slightly. The increased emissions, however, did not exceed any
existing emission standards.
SINTEF Report
Recently ratified Stockholm Convention on POPs (Persistent Organic Pollutants) aims to prevent and
reduce unintentional emissions of dioxins and furans. Cement kilns firing hazardous waste are explicitly
mentioned in the Stockholm Convention, Annex C part II, as “industrial source having the potential for
comparatively high formation and release of these chemicals to environment”. SINTEF, the largest
independent research organization in Scandinavia, prepared for the WBCSD (World Business Council for
Sustainable Development) / CSI (Cement Sustainability Initiative) a report on “Formation and Release of
POP’s in the Cement Industry” (March 2004). The report is based on more than 1,700 d/f measurements
from the early 1990’s until 2004. Data represents emissions levels from different types of kilns, performed
under normal and worst case operating conditions, with and without the co-processing of a wide range
alternative fuels and raw materials, including hazardous fuels. The conclusion of the study / report, based
on the data presented and discussed there show that (quoted):
1. Most cement kilns can meet an emission limit of 0.1 ng TEQ/Nm 3;
2. Co-processing of alternative fuels and raw materials, fed to the main burner or the
preheater/precalciner does not influence or change the emissions of POPs;
3. Cement kilns in developing countries presented here meet an emission level of 0.1 ng TEQ/Nm 3.
Basel convention / TDF
p. 4
Note that the current d/f standards of 0.2 ng TEQ/Nm 3. The SINTEF study clearly demonstrated that
cement kilns, even those using alternative or hazardous alternative fuels are well below that limit. This is
in full agreement with the statement of the CCME report mentioned earlier regarding the Canadian
cement kilns performance below 0.08 ng TEQ/Nm 3.
PCA Study
We should also mention a very timely and appropriate PCA (Portland Cement Association) commissioned
study on “Air Emissions Data Summary for Portland Cement Pyroprocessing Operations Firing Tirederived Fuels”. This study is in the final draft form, and as such, we are not in a position to quote or cite it
conclusions. It is expected, however, that it will be issued / published within the next few weeks, after
undergoing a final review. CAC expects to make this report available to Environment Canada in the
context of the Basel Convention and its draft guidelines on the use of TDF in cement kilns.
Perhaps at this point we will not be remiss if we mention that based on air emissions data applicable to 71
out of the 109 cement plants in the U.S., including data from 31 of the 43 cement plants presently firing
TDF, NOx, SO2, PM and d/f showed reductions in these emissions when TDF were used.
In conclusion, please consider this letter only a first, preliminary response to your request for comment on
the Proposed Revised Technical Guidelines on Environmentally Sound Management of Used Tires,
prepared by Brazil, under the Basel Convention. All the members of the CAC expressed, quoting, their
‘shock’ with respect to “hatchet job”, clear errors, misstatements, half-truths the author(s) of this draft
made concerning the cement co-processing section. All the opposition to the TDF, specifically, refers to
the same elusive paper by Dr. Schwartz – we were not able to find it yet.
We realize that the document that originates in Brazil was developed as part of the Brazilian
Government's efforts to impose a ban on the export of rethreaded tires to Brazil. The document is part of
a response to GATT meant to demonstrate environmental risks associated with imported tires. To this
end, it paints all the possible beneficial recycling and reuse of scrap tires with the same negative brush.
It is a flawed document, with potentially far reaching, damaging consequences. If this guideline were
adopted, it could lead to the end of tire co-firing in cement kilns worldwide and therefore would
significantly impact the economic viability of The Canadian cement industry, as well as its ability to meet
the requirements of Canada’s new regulatory framework.
The CAC members and its staff will be pleased to discuss this issue further. We are looking forward to
our meeting on January 22nd, 2008, and would like to re-iterate our invitation for you and your colleagues
to join us at the CAC Environment Committee meeting on February 5th, 2008, in Ottawa.
Truly Yours,
George J. Venta, P. Eng.
Director, Air Emissions and Environment
Cc:
Ms. Josée Lanctôt, Environment Canada
Members of the CAC Environment Committee
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