Page 169 - Materials Chemistry, Second Edition

150 Life Cycle Assessment of Wastewater Treatment

high elimination of pharmaceuticals (up to 99%), controls the growth of the pel-
lets, and facilitates the operation of the reactor. This aeration regime resulted in the
satisfactory elimination of different PhAC compounds. However, excessive growth
of the pellets has also been reported. The result shows the possibility of employ-
ing less expensive aeration regimes in the development of viable reactors for fungal
treatment (Rodarte-Morales et al., 2012). The successful employment of an aeration
regime has also been reported for other industrial wastewaters, that is, dye removal,
via fungal treatment (Cruz-Morató et al., 2014).
Batch reactor configuration has been employed extensively for PhAC removal
from wastewater via fungal treatment for decades. Rodarte-Morales et al. (2011)
reported complete removal of diclofenac, NPX, and IBP (spike concentration of 1 mg
−1
L ) by P. chrysosporium in a fed-batch stirred reactor with an air and oxygen supply
−1
by 24 h. The successful removal of triclosan (5 mg L ) in batch bed-packed reac-
tors has also been reported for immobilized laccase from Coriolopsis polyzona on a
diatomaceous earth support (Celite® R-633—contact time of 200 min—five cycles
[Cabana et al., 2009]), and T. versicolor (conjugation of laccase with the biopoly-
mer chitosan, 100% removal after 6 h [Cabana et al., 2011]). Immobilized laccase
from Myceliophthora thermophila on a sol-gel matrix has been tested for removal
of estrogens in both batch stirred tank reactors (BSTRs) (operating in cycles) and a
continuous photobioreactor (PBR). The removal of estrogen was reported as >85%
in the BSTR and in the range of 55–75% in the continuous PBR (Lloret et al., 2011;
Taboada-Puig et al., 2011). However, a short removal duration of 1 h has also been
reported by Auriol et al. for the complete removal of estrogens in municipal waste-
−1
water employing immobilized laccase with activities of 20,000 U L in batch reac-
tors (Auriol et al., 2008). The batch reactor configuration has also been employed for
the fungal treatment with near to complete removal efficiencies of different waste-
water effluents, including domestic sewage (Thanh and Simard, 1973), starch pro-
cessing effluent (Coulibaly et al., 2003), metal-contaminated effluent (Kapoor and
Viraraghavan, 1998), distillery wastewaters (Kumar et al., 1998), and pulp and paper
processing wastewater (Sumathi and Phatak, 1999). Continuous or flow reactor con-
figuration is less explored compared with the batch configuration, but examples of
employing this configuration for the decolorization of domestic sewage (Miyata et
al., 2000), distillery wastewater (Miyata et al., 2000), and wood processing wastewa-
ter (Manzanares et al., 1995) have been reported.

8.5 ADVANCED TECHNIQUES FOR TREATMENT
OF PHARMACEUTICALS IN EFFLUENTS

Sewage sludge is a byproduct of wastewater treatment, which results from the bio-
logical treatment of municipal sewage and is often used for cement production,
composting, or land improvement (Rodríguez-Rodríguez et al., 2012a). The last
option, called biosolids, is often considered as the most preferable choice, as it
contributes to the recycling of nutrients as well as increasing the fertility of the
land. Raw sewage sludge is treated to meet specific regulations for microbial patho-
gens and other classic pollutants before being applied as a land improver (Henry
and Cole, 1997). However, the current regulations mostly focus on pathogens and