Environmental Engineering Reference
In-Depth Information
The average number of port arrivals in some main European ports [26] varied
in 1996 between approximately 4400 ships per year for Helsinki (Finland) to
more than 25 000 per year for Piraeus (Greece) and Rotterdam (Netherlands).
In the first version of the Mam-Pec model [5] the shipping intensities and
ship dimensions in the port of Rotterdam and the North Sea shipping lanes
along the Dutch coast were used as a basis for the default emission scenarios
for commercial sea going vessels. In the recent emission scenario document
for the Biocide Directive [6] a similar approach was followed with different
settings for the number of ships and submersed surface areas based on the
Holtrop equation (Eq. 2). The recommended default values are summarized
in Table 3.
Little information is available on the application factor of a product (
F
i
),
which constitutes the fourth parameter in Eq. 1. In general, market share in-
formation of specific products is confidential, but it is clear that this type
of information is crucial for a proper estimation of the emissions. Especially
after implementation of the IMO treaty on antifoulants this will become more
important, as TBT will be diminished or banned, and the market share of
other biocide-based antifouling paints or biocide-free systems on sea going
vessels will become more important. With currently existing differences in
admission policies and regulation between countries, this may even vary on
a local scale. Especially for the categories of smaller ships (
<
25 m), where
application of TBT is not allowed, a reliable estimation of the actual usage
is not possible. In the EU-OECD emission scenario document (a worst case
approach with values of 0.9-0.95 for
F
i
is recommended.
Table 3
Recommended default emission scenarios for antifoulants in Europe (Biocide Di-
rective) and other OECD countries. Indicated are average underwater surface area and
number of ships moving (
N
m
)oratberth(
N
b
)forthedifferentlengthclasses
Length class
Surface
Shipping
Estuarine harbor
Marina
area (m
2
)
(m)
la e
N
m
N
b
N
m
N
b
<
50
31
500
50-100
1,163
3.9
11
1.8
100-150
3,231
1.7
5
0.4
150-200
6,333
1.6
5
0.4
200-250
10,469
0.4
1
0.1
250-300
15,640
0.5
2
0.1
300-350
21,844
0.1
Estimated emission*
773
2303
191
345
(g d
-1
)
∗
cm
2
Of compound with a leaching rate 2.5
µ
g
/
/
day and 100% application of product.
Adapted from: [5, 6]
