Issue 1

In the present study, the photocatalytic treatment of two synthetic textile dyehouse effluents was
investigated. The first synthetic effluent (SE1) is a Remazol Black B aqueous solution, while the
second one (SE2) is an aqueous mixture of sixteen dyes and auxiliary chemicals that are usually
employed in the textile industry. Various illumination sources were studied, while emphasis was
given on the use of simulated and natural solar light.
Results indicated that the use of solar irradiation can constitute an advantageous treatment strategy,
due to its energy efficient and environmentally friendly operation, for textile dyehouse effluents.
Specifically, it was observed that total decolorization and mineralization of SE1 occurred after about
120 min and 300 min, respectively, in the presence of at least 2 g L-1 TiO2, under natural sunlight.
On the other hand, total decolorization of SE2 was achieved only after 300 min of photocatalytic
treatment, while COD removal practically remained unchanged, at about 20%, regardless the
applied operating parameters, due to the presence of other organic and inorganic substances.
Furthermore, it was found that process efficiency was significantly affected by the catalyst loading.

This study investigates the partition of heavy metals in slag from the rotary kiln (SL), second
combustion chamber ashes (SCCA), filter cake (FC) from a bag filter and flue gas (FG) emissions
(both in particulate and gas phases) of the Istanbul medical waste incinerator (ISTAC). Eleven
targeted heavy metals (As, Cd, Co, Cr, Cu, Hg, Mn, Ni, Pb, Sb and Tl) in four matrices were
analysed for eight different date samples in 2008. The results obtained were evaluated according to
the metal species, furnace temperatures and other factors that affect the formation and accumulation
of the metals in the incineration cycle. According to the results, combustion temperatures, reactor
configuration and waste contents are the dominant parameters determining the volatility and
partitioning of metals in the combustion systems. The biggest waste portions were obtained for the
SL and the dominant metal species for the SL and SCCA were Cu (505,9±99,3 and 697,4±577,7 mg
per kg dry mass for SL and SCCA respectively) and Mn (238,0±154,6 and 199,9±180,4 mg per kg
dry mass for SL and SCCA respectively) . In the FC, the dominant species was Cu (166,8±128,1 mg
per kg dry mass) and this was followed by Mn, Ni and Hg. It is thought that cement and activated
lignite, which were added to the process as adsorbent materials, were affecting the contents of the
FC. Metals were divided into particulate and gas phases and maximum concentrations were
observed for Ni, Mn and Cr in a particulate phase of FG. Emission factors were considered and
mass balance calculations for metals were also conducted in the study.

Marine sediment contamination was evaluated in a set of sediment specimens collected from Izmir
Bay (Turkey) and from Mytilene Harbor (Greece) in the Aegean Sea. Eight sediment specimens from
Izmir (#IZ to #IZ8) and seven sediment specimens from Mytilene (#MYT1 to #MYT7) were analyzed
for their content in different classes of contaminants, i.e. inorganics, organic carbon (OC), and seven
polycyclic aromatic hydrocarbons (PAHs). Significantly higher levels of inorganic contaminants were
detected in Izmir vs. Mytilene sediment, and the highest inorganic contamination was detected in the
innermost sampling sites in Izmir Bay, namely sites #IZ1 to #IZ4. This was the case for Al, As, Cr,
Cu, Fe, Li, Mn, Pb, Ti and Zn. Granulometric analysis, OC and individual PAH congeners failed to
show any significant differences between total Mytilene and total Izmir Bay sediment samples.
Nevertheless, the sum of PAHs in sites #IZ2 to #IZ4 displayed significantly higher levels both vs. the
other Izmir sites and vs. all Mytilene sediment samples. The overall results point to higher pollution
status in Izmir Bay, especially in the innermost sampling sites, compared to Mytilene Harbor,
detected as inorganic contamination and as PAH contamination in some Izmir sampling sites.

To inform the further development of water pricing in Shiyang River basin, a typical arid region in
northwest China with agriculture as the major consumer of water, this research conducted a
contingent valuation study on farmer’s willingness to pay (WTP) for irrigation water. The results show
that the current irrigation water price is to low to achieve sustainable use of water. The main reason of
low price is not the farmer’s inability to pay, but their unwillingness to pay. Furthermore, a vicious
cycle of less willingness to pay and poor services exist in irrigation water management. The probable
solutions include the increase of public investment in water infrastructure and determine appropriate
price between surface water and groundwater. More important, enhance the communication and
cooperation between water use and water agency, the combination of price mechanism and other
instruments, such as positive incentives and the establishment of an independent water user
organization (WUO), are useful.