9 Struvite Crystallization: An Effective Technology …
159
as reported by Siciliano et al. (2013), utilizing alternative P-source (P-rich acidic
solution) has shown a significant improvement in the peroxide-oxidation treatment
for COD and NH 4 −N removal from landfill leachate.
9.5.1 Struvite as a Fertilizer
In order to attain sustainable agricultural practices, safe fertilizers have to be applied
to avoid harmful effects on plants, humans and surrounding environment. Struvite
has a significant role in the agricultural field. It is an eco-friendly and controlled
fertilizer as its nutrients’ releasing rate is slow. These characteristics make struvite
a more preferred fertilizer for different kinds of plants and crops, such as wheat
(Degryse et al. 2016), triticale, oats and alfalfa (Hilt et al. 2016), maize and tomato
(Uysal et al. 2014) and Chinese cabbage (Ryu et al. 2012). Thorough details on the
role of struvite in agronomic field are presented in Mukhlesur Rahman et al. (2014)
and Yetilmezsoy et al. (2017).
9.5.2 Cost Reduction Opportunities
In several types of wastewater, the concentrations of P and Mg are relatively low compared to NH 4 −N, hence large amounts of reagents are required to recover struvite.
As a result, more cost is added to the process. In most pilot and large-scale applications, struvite recovery applied on P-rich wastewaters did not require any P-addition
(Pastor et al. 2008; Suzuki et al. 2007). However, similar applications for NH 4 −N
recovery from NH 4 −N-rich wastewaters but poor in P, such as LL (Li et al. 2012;
Xiu-Fen et al. 2011), would be more costly as both Mg and P additions are needed.
Siciliano et al. (2013) reported that the cost of P reagents is a limiting factor that
influences the economic feasibility of struvite recovery. Therefore, the main target
of MAP technology, especially if applied as a pre-treatment process, should not be
the recovery of all NH 4 −N in the wastewater in order to avoid the high consumption
of Mg and P reagents. The following are suggested approaches to reduce the cost of
NH 4 −N recovery through struvite technology.
9.6 Struvite as Fertilizer in Agriculture
A number of studies have shown that applying struvite-fertilizer resulted with higher
nutrients uptake than other types of fertilizers (Uysal et al. 2014) as well as lower
heavy metals accumulation (Ryu et al. 2012). Precisely, the slow-releasing property
of MAP provides a controlled supply of nutrients for a longer period, which ensure
159
as reported by Siciliano et al. (2013), utilizing alternative P-source (P-rich acidic
solution) has shown a significant improvement in the peroxide-oxidation treatment
for COD and NH 4 −N removal from landfill leachate.
9.5.1 Struvite as a Fertilizer
In order to attain sustainable agricultural practices, safe fertilizers have to be applied
to avoid harmful effects on plants, humans and surrounding environment. Struvite
has a significant role in the agricultural field. It is an eco-friendly and controlled
fertilizer as its nutrients’ releasing rate is slow. These characteristics make struvite
a more preferred fertilizer for different kinds of plants and crops, such as wheat
(Degryse et al. 2016), triticale, oats and alfalfa (Hilt et al. 2016), maize and tomato
(Uysal et al. 2014) and Chinese cabbage (Ryu et al. 2012). Thorough details on the
role of struvite in agronomic field are presented in Mukhlesur Rahman et al. (2014)
and Yetilmezsoy et al. (2017).
9.5.2 Cost Reduction Opportunities
In several types of wastewater, the concentrations of P and Mg are relatively low compared to NH 4 −N, hence large amounts of reagents are required to recover struvite.
As a result, more cost is added to the process. In most pilot and large-scale applications, struvite recovery applied on P-rich wastewaters did not require any P-addition
(Pastor et al. 2008; Suzuki et al. 2007). However, similar applications for NH 4 −N
recovery from NH 4 −N-rich wastewaters but poor in P, such as LL (Li et al. 2012;
Xiu-Fen et al. 2011), would be more costly as both Mg and P additions are needed.
Siciliano et al. (2013) reported that the cost of P reagents is a limiting factor that
influences the economic feasibility of struvite recovery. Therefore, the main target
of MAP technology, especially if applied as a pre-treatment process, should not be
the recovery of all NH 4 −N in the wastewater in order to avoid the high consumption
of Mg and P reagents. The following are suggested approaches to reduce the cost of
NH 4 −N recovery through struvite technology.
9.6 Struvite as Fertilizer in Agriculture
A number of studies have shown that applying struvite-fertilizer resulted with higher
nutrients uptake than other types of fertilizers (Uysal et al. 2014) as well as lower
heavy metals accumulation (Ryu et al. 2012). Precisely, the slow-releasing property
of MAP provides a controlled supply of nutrients for a longer period, which ensure