Journal of Environmental Accounting and Management Treatment of ...

Journal of Environmental Accounting and Management 6(2) (2018) 167-184 Volume 1 Issue 1 March 2013

ISSN 2325-6192 (print) ISSN 2325-6206 (online)

Journal of Environmental Accounting and Management

Journal of Environmental Accounting and Management Journal homepage: https://lhscientificpublishing.com/Journals/JEAM-Default.aspx

Treatment of Highly Polluted Industrial Wastewater Utilizing Clean and Low Cost Technologies: Review Article Ibrahim Abdelfattah† Water Pollution Research Dept., National Research Centre, 33 EL Bohouth St., P.O. 12622, Dokki, Giza, Egypt Submission Info Communicated by Z.F. Yang Received 11 December 2017 Accepted 13 April 2018 Available online 1 July 2018 Keywords Hazardous Wastewater Treatment Clean Low cost Technologies

Abstract A comprehensive review article dealing with clean and low cost technologies for treatment of highly polluted industrial wastewater will be detailed. These technologies covering: the biological processes including anaerobic methods with high production of biogas and lower production of sludge, aerobic methods will be excluded due to the higher sludge production and the added cost of aeration. Biosorption and adsorption processes including different clays and plant wastes will be included due to economic reasons and sustainability factors. Furthermore, advanced oxidation processes (AOPs) which are utilized in case of the higher ranges of toxic effluents as a cost effective technologies will be discussed. Solar processes which utilize the nature UV-source will be also involved. The review article is supported with case studies for relieving the noxious effects of wastewaters before discharging it into the surrounding environment. A valuable recommendations are presented to finalizing the review article drawing the best planning to get rid of the hazardous effects of the industrial effluents. ©2018 L&H Scientific Publishing, LLC. All rights reserved.

1 Background Egypt is classified as a water scarce country, where each person has about 600 m3 of fresh water per year. The rapid acceleration of economic growing industrialization and demographic development lead to increasing of water demand, furthermore, water use allocation in Egypt showed more than 6% of fresh water resource is consumed by industries. A Considerable number of industries produce a highly loaded wastewater containing high concentrations of some or all of the COD, BOD, PO4 , NO3 NO2 , NH3 , phenols, heavy metals, pesticides etc., such pollutants cause surface and groundwater contaminations. The following sketch in Figure 1 illustrates that; pollutants could reach and affect our health through different ways including the significant way which is water, these pollutants in wastewater are the reason of widespread of many dangerous diseases in Egypt. The highly polluted wastewater could be produced from diverse industries including: for example, food processing, paper mill, slaughter wastewaters which produce oxygen demanding substances, metal processing which produce heavy metals, dying and textile which produce toxic organics, and pesticide product ion which produce toxic organics, pharmaceutical which produce toxic organics, tanning which produce heavy metals and † Corresponding

author. Email address: [email protected] ISSN 2325-6192, eISSN 2325-6206/$-see front materials © 2018 L&H Scientific Publishing, LLC. All rights reserved. DOI:10.5890/JEAM.2018.06.007

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Ibrahim Abdelfattah / Journal of Environmental Accounting and Management 6(2) (2018) 167–185

Fig. 1 Sketch of the mechanisms of distribution and the transformation of the substances in the environment.

hardly degradable organics, paper mill which produce hardly degradable organics, chemical which produce toxic organics and heavy metals, etc. The term, clean wastewater treatment technologies, used to describe processes that require as few nonrenewable resources as possible to reduce the waste or could be defined as, the processes that add minimal noxious loads as possible to the environment.

2 Introduction Biological treatments still the most widely used technologies in industrial wastewater treatment due to their low cost and effectiveness which discussed in the treatment of chemical industry wastewater from construction chemicals and plastic shoes manufacturing industry (Nasr et al., 2007). Abou-Elela et al. (2015) concluded that; the cost effective biological treatment technologies reach with the treated wastewater effluent for reuse in the unrestricted irrigation. Adsorption and bio-sorption processes including the removal of hazardous heavy metals or organics from industrial wastewater (Aksu and Yener, 2001; Achak et al., 2009; Abdelfattah et al., 2016a,b). In some cases, AOPs including Fenton, photo-Fenton and photo-catalysis could be clean and cost effective treatment technologies to get rid of hazardous toxicants from highly polluted industrial wastewater (El-Awady et al., 2015; Abdelfattah, 2011; Ismail et al., 2015; Ismail et al., 2016; Ismail et al., 2018). The most attractive state of the art in the field of industrial wastewater treatment is that field associated with the solar-catalysis, including detoxification, destruction or mineralization of organic pollutants in the industrial wastewater (Marcelino et al., 2015; Sharon and Reddy, 2015; Blanco et al., 2009; Robert, 2002).


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Inasmuch the difficult economic situation in Egypt, the researchers in the field of wastewater treatment focus in their research activities on the direction of the low cost and clean technologies which could reach with the treated wastewater for reuse. In this review, a comprehensive article in clean and low cost treatment technologies for highly polluted industrial wastewater will be presented, covering: 1) the biological processes including anaerobic methods, aerobic methods will be excluded due to the sludge production, aeration cost. 2) biosorption and adsorption including different clays and plant wastes; 3) AOPs and 4) solar processes. Furthermore, case studies elucidating the biosorption and AOPs as a low cost technologies for treating the highly loaded real industrial wastewater will be included. Wastewater is collected from a metal industry located at Sadat city, Egypt and subjected to biosorption process utilizing the peanut husk powder (Abdelfattah et al., 2016b). The AOPs is discussed in the case study in order to apply it in real industrial wastewater treatment, photoFenton reaction and TiO2 -photocatalysis with the UVFSR (UV-free surface reactor) is applied to treat a highly hazardous wastewater collected from a metal industry, Stuttgart, Germany, the real industrial wastewater was rather problematic and could not be treated properly by other wastewater treatment methods such as conventional biological or chemical processes (Abdelfattah, 2011). Applications of clean and low cost technologies which can be applied in the developing countries in the field of onsite treatment of industrial wastewater for reuse will be discussed in this article.

3 Biological anaerobic processes Anaerobic treatment methods are the most advisable choice for the treatment of highly polluted effluents which loaded with biodegradable organics (Rajeshwari et al., 2000). The anaerobic processes are beneficiary procedures in relation to the environmental and economical protections. Low cost, robust, simple in set-up and operation mechanisms, less production of excess sludge and throughout the process a biogas or hydrogen is produced, all of them are causing the priority of utilizing the anaerobic processes in the field of industrial wastewater treatment (Rajeshwari et al., 2000; Chan et al., 2009). The following equation (1) elicited a general mechanism of the anaerobic treatment of industrial wastewater which is highly polluted with organic materials. Anaerobic bacteria

Organic mater −−−−−−−−−−→ H2 O +CO2 +CH4 + Bacterial Cells.

(1)

In the anaerobic process, the detaining of the worthy biomass can be achieved through: a) formation of extremely settleable sludge and gas separation, e.g. the anaerobic baffled reactors (ABR) and upflow anaerobic sludge blanket reactors (UASB) b) attachments of the biomass on to a carrier materials e.g. anaerobic sludge bed reactor (ASBR) and fluidized bed reactors (FBR), c) the biomass is reserved between the backing materials e.g. upflow anaerobic filter (UAF) and downflow anaerobic filter (DAF) (Rajeshwari et al., 2000; van Haandel and van der Lubbe, 2012). Requirement of pre-treatment, dilution, control of operating conditions, etc. are factors that determine the preference of a particular type of digester over others. In case of wastewater collected from slaughterhouse, an anaerobic contact reactor could be used and the pre-treatment steps can be excluded. On the other hand, the utilization of high rate digester like UASB, it is needed mandatory pre-treatment step for removal of the oil, grease and suspended solids (Rajeshwari et al., 2000). The anaerobic treatment processes are distinguished from the aerobic processes by the following advantages: low energy consumption, low sludge production and no or little nutrient needed otherwise a considerable amount of biogas is produced as a source of clean energy. The following diagram in Figure 2 illustrates the 4-steps pathway of the production of biogas throughout anaerobic processes. The anaerobic treatment processes play as clean energy resources through production of hydrogen. Won and Lau (2011) stated that; a production of 3.04 L H2 /L reactor and at pH 4.5, HRT 30 h, and organic loading rate of 11.0 kg COD/m3 ·d had been achieved.

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Fig. 2 The 4-steps pathway of biogas production.

The experimental results obtained by Perez et al. (1999) confirmed that; biodegradation of vinasses in anaerobic fluidized bed reactor (AFBR) with a porous support media provides a good chemical oxygen demand (COD) removal of 80% to 97% and a high production of biogas of 1.08 m3 /m3 ·d. Another study confirmed a removal of COD of 85-92% 1.8 m3 /m3 ·d (Mar´ın et al., 1999). The sustainable treatment technologies employ the anaerobic processes for the agro-food industrial wastewater, the upflow anaerobic fixed bed reactor using different packing materials such as; polyethylene, polypropylene pall rings, polyurethane foam, carbon felt and waste tire rubber had been used as a cost effective materials which help to reduce hydraulic retention time, minimize the required volume of the reactor, and also the total cost could be reduced; and the upflow anaerobic sludge blanket (UASB) reactor, hybrid systems are employed (Rajagopal et al., 2013). According to the support materials used, three upflow anaerobic fixed bed reactors for the treatment of industrial wastewater collected from coffee bean processing were evaluated. Crushed stone, furnace cinders and polyurethane foam with porosities of 48%, 53% and 95% respectively have been used as packing materials. The treatment process achieved in 139.5 L reactors; COD of the influent (978; 2401 and 4545 mg·L−1 ) and detention time of 1.3 days, the maximal COD removal 83% is obtained when the reactor filled with foam. The higher porosity in the reactor filled with foam provide its higher performance which attributed to its greater collection of biomass (Fia et al., 2012). Thermophilic anaerobic contact reactor provided a real solution for treating of potato-chips wastewaters which had a high organic loading rate (0.6 to 8 kg COD/m3 ·d) and the treated effluent reached the removal efficiencies of COD were found to be 86-97% and the methane yield was found to be 0.42 m3 CH4 /kg CODremoved at 50 ◦ C (S¸ntürk et al., 2010). Inverted anaerobic sludge blanket reactor is used to treat a highly phenolic and lipid content wastewater effluents collected from olive mill industry. The wastewater had concentrations of COD (5 to 48 g·L−1 ) and the


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hydraulic retention time (10 and 5 days).A removal of COD and phenols of more than 70% and 40% respectively is achieved (Gonçalves et al., 2012). Wastewater collected from cassava starch processing which containing a high COD concentration was subjected to the treatment processes using the up-flow multistage anaerobic reactor (UMAR). The anaerobic treatment startup is successfully accomplished in 22 d. 87.9% of the COD was removed at hydraulic retention time (HRT) of 6.0 h at fixed feeding concentration of 4000 mg/L of COD. Furthermore, 77.5-92.0% COD were removed at organic loading rates of 10.2-40.0 kg COD/(m3 ·d) at fixed HRT of 6.0 h (Sun et al., 2012). An evaluation of the performance of treatment of cereal-processing industrial wastewater utilizing a pilotscale of upflow anaerobic sludge blanket at low temperature (17 ◦ C) for more than 300 days had been performed. The organic loading rates were gradually increased from 4 to 8 kg COD/m3 ·d by increasing the influent COD and keeping the hydraulic retention time (5.2 h). High removal efficiency of COD (82 to 92%) had been achieved. The highest performance of the (UASB) is achieved at the rate of 8 kg COD/m3 ·d (Esparza et al., 2011). The treatment of different kinds of wastewaters had been achieved using upflow anaerobic filter (UAF) through the study presented by Rajinikanth et al. (2009) overutilization of different 10 L effective volumelab-scale UAFs, all of them packed with polyethylene material which had a double action in reserving the biomass and filtration rule. The wastewater collected from different agro-food industries were varying in COD concentrations and chemical compositions, 1.9-30 g COD/L, the limiting parameter is the HRT for the low strength wastewater 1.9 g COD-4 h related to OLR of 12 g COD/L·d. For the higher strength wastewater the OLR was the determining parameter which more affected with the composition of the wastewater more than the concentration, such in case of the winery wastewater which had COD of 20 g/L had the highest OLR of 27 g COD/L·d and the removal efficiency of COD reached 80%, in comparison with the fruit canning wastewater (concentration of 10 g COD/L) which had 19 g COD/L·d of OLR. Flavor industrial wastewater had been treated via the UASB and more than 60% of the COD was removed in different OLR 6.8-9 kg COD/m3 ·d at HRT of 8 and 6 hours respectively (Nasr et al., 2006). Quan et al. (2007) concluded that; a continuous removal (84%) of total aromatic hydrocarbons; benzene, biphenyl and naphthalene had been achieved and 90% of the COD had been removed by utilizing anaerobic filter reactor (AF). An intensive work in the isolation and identification of the yeast collected from the soil contaminated with glutamate fermentation wastewater in glutamate industry had been achieved and the cultured mixture of yeasts had been used for the treatment of highly loaded glutamate fermentation wastewater resulted in a removal of 85% of the COD was achieved (Zheng et al., 2005).

4 Adsorption and bio-sorption processes Biosorption of the dissolved heavy metal or toxic organics is the removal of these toxicants from water by certain bio-materials which have the ability to attach and concentrate the metals ions or toxic organics. Cost effectiveness, regenerative and allow metal recovery technology, minimization of chemical or biological sludge are the main advantages of biosorption over conventional treatment methods (Sud et al., 2008; Abdelfattah et al., 2016a,b). The following Table 1 summarized the main kinds of biosorbents which used in the biosorption process. Various chemical groups including, carboxyl, hydroxyl, sulfate and amino, amide groups even double bonds play considerable roles in the biosorption mechanism. The pH of water medium and the biosorbent dose have a large impact on bio-sorption performance. The most prevalent mechanisms for the bio-sorption of most heavy metals are, the ion exchange and complexation, diffusion through pores and adsorption on surface etc. (Sud et al., 2008; Arief et al., 2008, Abdelfattah et al., 2016a,b). Different research groups have done a lot of efforts to remove heavy metals ions through the bio-sorption technologies as summarized in Table 2(a) and (b). When one talking about absorption, it has to be mentioned the first scientists who gave a thorough explanation of that process. The most widely used mathematical descriptions of the sorption process is presented by:

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Table 1 Kinds of biomasses used for preparation of biosorbents. Biomass source

Examples

Agriculture waste Fruit or vegetable wastes, rice straws, wheat bran, Corn cob, soybean hulls, Plant residues, tree barks, weeds, etc. Industrial waste

Fermentation wastes, sawdust, activated sludges, food/beverage wastes, anaerobic sludges, etc.

Bacteria

Gram-positive bacteria, gram-negative bacteria, cyanobacteria, etc.

Algae

Micro and macro algae, brown seaweed, and red seaweed

Fungi

Molds, mushrooms, and yeast

Animal waste

Bone powder, Fish peel, Feathers, etc.

Table 2 (a) Bio-sorption capacities of different bio-sorbents for heavy metals (Nickel, Lead and Manganese). Metal

Ni2+

Pb2+

Mn2+

Bio-sorbent Corn cob Maize cob Saw dust Maize cob Corn cob powder Corn cob Sawdust Myriophyllum spicatum Lichen (Cladonia furcata) Macro-fungus (Amanita rubescens) Saccharomyces cerevisiae yeast Corn cob Leaves of dump palm Maize stalk

Maximum Adsorption (mg/g) 12 18.4 35 10 14.6 32.4 15.9 55.1 12.3 38.4 72.5 12 3 5.5

Reference (Abdelfattah et al., 2016a) (Muthusamy et al., 2012) (Adie et al., 2012) (Adie et al., 2012) (Arunkumar et al., 2014) (Abdelfattah et al., 2016a) (Bulut and Tez, 2007) (Yan et al., 2010) (Sari et al., 2007) (Sari et al., 2009) (Amirnia, 2015) (Abdelfattah et al., 2016a) (Jonathan et al., 2011) (El-Sayed et al., 2011)

Table 2 (b) Bio-sorption capacities of different bio-sorbents for heavy metals (Cadmium and Cobalt). Maximum Adsorption (mg/g) 24 25 20 5.2 32.5

Metal

Bio-sorbent

Cd2+

Corn cob Zea maize waste Maize cob Saw dust Macrofungus (Amanita rubescens)

Co2+

Corn cob Pine saw

3.2

(Abdelfattah et al., 2016a)

dust lemon peel

56

(Musapatika et l., 2012)

Amaranthus hybridus

Reference (Abdelfattah et al., 2016a) (Jamil and Munwar, 2009) (Ibrahim, 2013) (Ibrahim, 2013) (Sari et al., 2009)

22

(Bhatnagar et al., 2010)

9.5

(Egila et al., 2010)

a) The Langmuir sorption equation isotherm which is based on the assumptions that maximum adsorption corresponds to a saturated mono-layer of adsorbate molecules on the adsorbent surface (Langmuir 1916). The essential characteristics of Langmuir dimensionless constant separation factor or equilibrium parameter, RL , which is defined by the following equation: 1 , (2) RL = 1 + KL ∗C0 where KL is a constant related to the sorption energy, C0 is the initial concentration.


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The value of RL is calculated from above expression, the nature of the adsorption process is Favorable when (0< RL < 1). b) The Freundlich sorption isotherm equation which gives an expression encompassing the surface heterogeneity and the exponential distribution of active sites and their energies (Freundlich 1906). The equation in linearized form is: (3) ln qe = ln KF + (1/n) lnCe , where Ce is the equilibrium concentration in mg/L, qe = amount of adsorbate adsorbed per unit weight of adsorbent (mg/g). “KF ” is a parameter related to the temperature and “n” is a characteristic constant for the adsorption system, when the values of “n” are between 2 and 10, it exhibit favorable adsorption behavior. Intel et al. (1998) used different bentonitic clays for removal of Cu and Pb from wastewater and the adsorption capacities reached 20-70 mg of Cu/gram of clays and 80-205 mg of Pb per gram of clays. Achak et al. (2009) stated that, the removal of contaminants from olive mill wastewaters is achieved using banana peel which has a high efficiency for removing the phenolic compounds from olive mill wastewaters. The adsorption process of the phenolic compounds is characterized by: The high adsorption capacity of phenolic compounds (689 mg/g) and the adsorption process was very fast (equilibrium reached in 3 h) at alkaline pH, Langmuir and Freundlich isotherms provide good correlations provided a chemical-sorption interaction occurs between the phenolic compounds and the adsorption sites. Another study has investigated that, the using of corn cob as biosorbent for removal of metribuzin herbicide from wastewater is achieved and the monolayer sorption capacity is obtained and found to be 4.07 mg of metribuzin per each gram of corn cob at pH of 5 in 70 min contact time at room temperature (Ara et al., 2013). Boucher et al. (2007) presented the study which used the oilseed press-cake and proved their efficiency for removal of pesticides carbaryl, atrazine and parathion from wastewater. Lemić et al. (2006) carried out adsorption tests to determine the efficiency of organo-zeolite for removal of atrazine herbicide, lindane insecticide and diazinone insecticide from water. The adsorption capacities were 2.0 micromol of atrazine per each gram of organo-zeolite 4.4 micromol of diazinone per each gram of organo-zeolite and 3.4 micromol of linden per each gram of organo-zeolite. A simulated ground water contaminated with carcinogenic chorophenols is subjected to sorption process utilizing chitosan, the equilibrium and kinetics were studied and the uptake of the chlorophenols reached 187.3, 113.2, 78 mmole/kg of polymer at different temperature 5, 15 and 25◦ C respectively (Zheng et al., 2004). 4.1

Case study

Wastewater is collected from a metal industry located at Sadat city, Egypt and subjected to biosorption process. The metal industry produced about 300 m3 /month of wastewater polluted with varieties of heavy metals. The biosorption process is carried out using the peanut husk powder (PHP). The characteristics of the raw wastewater and the treated effluent are illustrated in Table 3 (Abdelfattah et al., 2016b). After optimal steady state is reached, the percentage removal of heavy metals are: 50.9%, 100%, 37.9%, 45.4%, 95.3%, 23.6%, 41.3%, 38.4%, 56.4% and 30% for CN− , Pb2+ , Zn2+ , Cu2+ , Fe3+ , Ni2+ , Cd2+ , Mn2+ , Cr3+ and Co2+ respectively as shown in Table 3. The operating conditions were: 5 g/L of PHP, 1 h mixing, at pH of 6.6 and at ambient temperature. Extended treatment process should achieved to reach a complete removal of the heavy metals. Also the durability of the PHP is proved without altering capacity of the sorbent for removal of heavy metals by acid-distilled water washing and drying at 80 ◦ C (Bakir et al., 2010; Lau et al., 2003; Jalali et al., 2002; Hashim et al., 2000). The biosorption treatment plant is shown in Figure 3. The construction and running cost of the treatment process is calculated to be 550 $ and 0.5 $ respectively.

5 AOPs as clean and low cost treatment technologies for highly polluted industrial wastewater Due to ever stricter wastewater legislation around the world, factories and companies which produce nonbiodegradable and recalcitrant organics in their effluents were interested in AOPs (Abdelfattah, 2011). These

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Table 3 Efficiency of using peanut husk for industrial wastewater treatment. Metal ions and CN−

a Concentration

of metal ions in mg/L 11

b Concentration

of metal ions in mg/L

%Removal of metal ions

5.4

50.9

Pb2+

0.26

0

100

Zn2+

11.61

7.2

37.9

Cu2+

11.55

6.3

45.4

Fe3+

2.13

0.1

95.3

Ni2+

30.76

23.5

23.6

Cd2+

46

27

41.3

Mn2+

52

32

38.4

Cr3+

44.69

19.45

56.4

Co2+

20

14

30

a: before treatment, b: after treatment

Fig. 3 Schematic diagram of proposed bio-sorption treatment plant.

industries produce refractory and toxic pollutants, herewith increasing the environmental fierce impacts. (AOPs) are defined as: the technologies in which water and wastewater are treated by oxidation of the recalcitrant pollutants un-specifically utilizing the active hydroxyl radicals (HO’) generated nearby in sufficient quantity. Fortunately, it is an important feature of the (HO’), it has a non-selectivity property and the oxidative power in wastewater purificationsunder ambient temperatures and pressure. (Abdelfattah, 2011; Fujishima et al., 2007; Pera-Titus et al., 2004). Because of the critical economic situation, it is mandatory to develop efficient technologies that can relive the hazardous impact of these pollutants to the environment and at the same time are cost effective (Rodriguez et al., 2010; Amorim et al., 2013; Abdelfattah, 2011). Ultraviolet (UV) is an adding value in AOPs due to; it enhance steadily the efficiency of the removal of pollutants (Agullo-Barcelo et al., 2013). AOPs can increase biodegradability and decrease toxicity (Chan et al., 2012; Nasr et al., 2016) and furthermore, it can also destroy refractory pollutants by enhancing the mineralization (Fujishima et al., 2007), due to the former reasons, AOPs represent clean wastewater treatment technologies. Researchers had been classified the AOPs according to the existence or absence of the UV, shown in Figure 4 (Abdelfattah, 2011).


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Fig. 4 Classification of relevant AOPs for wastewater treatment according to the presence/absence of UV (Abdelfattah, 2011).

Fig. 5 Classification of relevant AOPs for wastewater treatment according to phase status (Stasinakis, 2008).

Other researchers classified it according to the phase status of the degradation of the pollutants, the degradation can occur in a single phase (homogenous) or can occur in multi-phases (heterogeneous) shown in Figure 5 (Stasinakis, 2008). Accordingly, the (HO’) can be generated throughout Fenton reaction which formulated simply as the following equation (4): (4) Fe2+ + H2 O2 → Fe3+ + OH − + OH g Irradiated AOPs added (HO’) in photolysis of hydrogen peroxide, equation (5): hv

H2 O2 → 2OH g

(5)

The photo-Fenton reaction can produce added radicals by oxidation of Ferric ions as in equation (6): hv

Fe2+ + H2 O → Fe2+ + OH g + H +.

(6)

In photo-catalysis, the irradiation of semiconductor like TiO2 producing so-called electron-hole pairs at the TiO2 surface, equation (7): hv (7) TiO2 → e− + hole+ .

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Photo-induced holes are strong oxidizers which oxidize water molecules to produce hydroxyl radicals, equation (8): (8) H2 O + hole+ → OH g + H +. Furthermore, the electrons (e− ) at the TiO2 surface reduce hydrogen peroxide, generating OH-radicals as well, equation (9): (9) H2 O2 + e− → OH g + OH −. AOPs had been proven to be effective in the mineralization and degradation of a wide range of toxicants in industrial wastewater such as pharmaceutical wastewater (Durán et al., 2013; Michael et al., 2013), pesticide, herbicide and insecticide wastewater (Mico et al., 2013; Ismail et al., 2015; Ismail et al., 2016), different phenolic wastewater and wastewater containing cyanotoxins and carcinogenic compounds, endocrine damaging compounds (de Freitas et al., 2013; Sanchez-Polo et al., 2013; Prieto-Rodriguez et al., 2013), petroleum refinery wastewater (Saien and Nejati, 2007; Corseuil et al., 2011; El-Awady et al., 2015), textile and dying wastewater (El-Awady et al., 2005; Nezamzadeh-Ejhieh and Banan, 2011; Foletto et al., 2012), landfill leachate (Rocha et al., 2011; Vilar et al., 2011) and wastewater containing hormones (Frontistis et al., 2012). 5.1

Case study

In order to apply the AOPs in industrial wastewater treatment, photo-Fenton reaction and TiO2 -photocatalysis with the UVFSR (UV-free surface reactor) is applied to treat a highly hazardous wastewater collected from a metal industry, Stuttgart, Germany (Abdelfattah, 2011). The real industrial wastewater was rather problematic and could not be treated properly by other wastewater treatment methods such as conventional biological or chemical processes. It should be noted that industrial wastewater treatment in Germany is subject to a high standard environmental legislations, the authorities are permitted to tighten the limits and to prescribe special modern treatment methods which are state-of-the-art. The only disposal route was a very expensive one, namely incineration as liquid waste in a hazardous waste incineration plant, the cost to incinerate 1 m3 of the wastewater is 400 . Some batch experiments on the laboratory scale are obligatory to determine the optimal conditions which are important for the dimensioning of a large plant and calculating its running costs. The origin of the wastewater components is a big aluminium foundry of industry. In the foundry, the sand-resin moulds were filled with molten aluminium which has a temperature of about 700 ◦ C. In the process, parts of the moulding resins get pyrolysed. The noxious and odorous pyrolysis vapours within the casting hall are sucked off and routed into a scrubber; downstream the vapours enter four large bio-filters for treatment of the waste gas. The examined wastewater consists mainly of the scrubber water plus some condensates from the bio-filters. It is highly-loaded with typical organic pyrolysis products from resin decomposition mainly phenols and cyanide. The wastewater is collected in a tank and removed from time to time by a waste disposal contractor. The following Table 4 shows the composition of the mentioned wastewater and the fluctuation range of relevant ingredients during one year. The table quickly reveals the problem with this wastewater and the strong fluctuations. Based on the experience of the pretests in the lab-scale reactor, large-scale tests for continuous flow operation of the 1 m3 , 2×17 kW UVFSR was installed. Figure 6 shows the onsite arrangement of the reactor with its peripheral installations. Wastewater used in case of batch treatment had the following characterizations; pH, COD, phenol index, cyanide and zinc of 6.9, 28700 mg/L, 300 mg/L, 30 mg/L, 1.8 mg/L. The optimal operating conditions found to be; in 1 m3 of UVFSR, ferrous sulphate (25%) of 2.9 L, 21.5 L of H2 O2 the adjustment the pH to 2.5 with 14.3 L of sulphuric acid is achieved, in addition to 0.3 L of antifoam was added to reach the target values of the phenolic index, cyanide and zinc were less than; 100 mg/L and 0.1 mg/L, 0.5 mg/L respectively. Test conditions for the large scale continuous industrial wastewater treatment utilizing the photo-Fenton method are: in 1 m3 UVFSR, the following reactants are pumped; wastewater influent flow rate was 0.42 m3 /h; hydrogen peroxide (50%), sulphuric acid (37%), ferrous sulphate (25%) and antifoam were pumped in 9 L/h, 6 L/h, 1.2 L/h, and 1.2 L/h respectively. The results of the continuous flow operation of the photo-Fenton treatment


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Table 4 Relevant parameters and fluctuation range of investigated wastewater. Wastewater Parameter

Quality Characteristics (fluctuation range)

Volume stream

17-70 m3 /month

Color/Transparency

Light brown to dark brown / turbid

Odor

Pyrolysis smell, burnt smell

Oil & Grease

10-18%

Settleable matter

7-13%

pH value

6-9.5

COD (mg/L)

3000-55000

DOC (mg/L)

500-10000

Phenol index (mg/L)

10-800

Cyanide (mg/L)

Zero-30

Zinc (mg/L)

0.2-400

Fig. 6 UVFSR arrangement for continuous flow, large-scale treatment.

process showed a removal of phenolic compounds and the cyanides under the desired limits after steady state is reached. Utilization of TiO2 -photocatalysis lead top using of less chemicals in comparison with the photo-Fenton rout where the optimal pH is a wide range between 6 and 9, there is no need for the adjustment of the pH, whereas the nature pH of the raw wastewater is 6.6. Hydrogen peroxide (50%) dose of 25 ml/L with addition of 0.2 g/L titanium oxide powder (Degusa-P25), addition of 0.1 ml/L antifoam is mandatory to be added. The results showed that; a removal of phenolic cyanide compounds reaching the required concentrations in 30 minutes irradiations was achieved. Taking into account the experience and findings of the pre-tests (laboratory-scale tests, large-scale test and

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Fig. 7 Technical concept of industrial wastewater treatment.

post-tests), a practical wastewater treatment concept was elaborated. The following Figure 7 shows a technical concept which has three treatment stages: (1) Oil and sediment separation within a large storage and calming tank. (2) Photochemical reactor with a 1 m3 , 34 kW UVFSR for lowering phenol index and cyanide content of aqueous phase. (3) Heavy metal (zinc) hydroxidic precipitation in a stirred tank reactor with subsequent sludge treatment. (4) The waste oil and hydroxidic sludge filter cake must be disposed of from time to time and the same applies to the sediment from the calming tank, which is routed to the chamber filter press. Compared with the disposal price of about 400 /m3 for the actual wastewater treatment by incineration (without transport), the AOPs including photo-Fenton and TiO2 -photocatalysis treatment seems to be an interesting economical alternative, around 90 was the estimated running cost. AOPs are alternatives to the incineration process which has many disadvantages (Abdelfattah et al., 2011; Munter, 2001).

6 Solar-AOPs applications The need to find alternative energy sources which are cost-effective and easy to get, because the economic assessment of the treatment system often compromised in terms of energy costs (Saien and Nejati, 2007; Malato et al., 2009). The replacement of artificial ultraviolet radiation by natural and cleaner solar source acts in the direction of reduction of electricity losses by transportation (Rocha et al., 2011).The utilization of solar radiation which is abundant in Egypt (3650 h/a) pushed in direction of energy saving strategy. Figure 8, showed the types of solar-AOPs which could be used in the industrial wastewater purifications. Solar-AOPs could be applicable for treatment of IWW having bio-recalcitrant organic pollutants and also for disinfection for removing pathogens (Malato et al. 2009). Pérez et al. (2013) studied the economic assessment on a combined process, solar-Fenton/MBR (membrane bioreactor), to treat hazardous and toxic five commercial pesticides industrial wastewater in different concentrations (50-500 mg/L DOC). The authors concluded that; in AOPs the increasing in the concentrations not forever offset increasing in costs due to the mineralization factor of organics, the use of combined system (solarFenton/MPR) resulted in a reduction of cost by 20%, the higher treated volumes presented a competitive costs, 1-1.9 /m3 . Sufficient degradation is obtained by using solar-photo-Fenton treatment for raising the biodegradability of the pesticides industrial wastewater for further MBR process, this technology is 12% cost reduction


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Fig. 8 Solar-AOPs used in the industrial wastewater purifications.

compared to coupling with a conventional activated sludge process (Pérez et al. 2013). Monteagudo et al. (2012) applied the solar technology for treatment of the winery industrial wastewater by solar photo-Fenton process. Figure 9 illustrated the experimental setup of the pilot plant for a reactor of volume of 16 L. The pilot plant based on a compound parabolic collector (CPC) solar reactor to remove the total organic carbon (TOC) content from the winery wastewater. Ferrioxalate-induced solar photo-Fenton process is used and a removal of 61% of the TOC is achieved after 6 hours exposure to the solar irradiation. The residual organic content in the solar treated effluent can be treated biologically for further oxidation thus reducing the total treatment costs (Monteagudo et al., 2012). Garcia-Garcia et al. (2015) proved an elimination of 89% of COD and removal of 97% and 91% of color and turbidity respectively during the treatment of industrial wastewater collected from end of an industrial park which receives the industrial discharge from 136 factories. The treatment method is achieved by applying electrocoagulation (EC) and electrooxidation (EO) processes powered by solar cells. Another authors studied the action of Solar-Fenton in treatment of different industrial wastewaters containing; pesticides, phenols and hydrocarbons using Solar-Fenton process utilizing a concentrating parabolic trough reactor (PTR). Removal of about90% of the TOC content had been achieved in about 3 h irradiations (Nascimento et al., 2007). Zhang et al. (2014) represented an extensive review in the field of utilizing the solar-TiO2 photocatalysis in the treatments of different kinds of industrial wastewaters such as; paper mill wastewater, textile wastewater, and olive mill wastewater, the authors concluded that, solar TiO2 photocatalysis method can provide a promising alternative for degradation and removal of the hazardous pollutants in different industrial wastewaters. *OS: Oil Separation, An: Anaerobic Treatment, BS: Biosorptions, AOPs: Advanced Oxidation Processes, SAOPs: Solar-Advanced Oxidation Processes

7 Recommendations Recommendations for using different kinds of treatment technologies for treating varieties of highly polluted industrial wastewater is presented in Table 5.

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Fig. 9 Experimental setup based on a CPC pilot plant. Reactor volume: 16 L: (a) Image; (b) Schematic (according to Monteagudo et al., 2012). Table 5 Recommendations for using different kinds of treatment technologies. Source of pollutants

Industrial wastewater

Treatment technologies*

BOD5

COD

Oil

Phenols

Heavy metals

Food processing

×

×

×

–

–

OS, An

Olive mill

×

×

×

×

–

OS, BS, AOPs, SAOPs, An

Chemical & pharmaceutical

×

×

×

×

×

OS, BS, AOPs, SAOPs

Metal

×

×

×

×

×

OS, BS, AOPs, SAOPs

Dying & textile

×

×

–

×

–

AOPs, BS, SAOPs, An

Tanning

×

×

×

×

×

OS, AOPs, SAOPs, An

Paper mill

×

×

–

–

–

AOPs, SAOPs, An

*OS: Oil Separation, An: Anaerobic Treatment, BS: Biosorptions, AOPs: Advanced Oxidation Processes, SAOPs: Solar-Advanced Oxidation Processes

8 Conclusions • There are different types of treatment technologies that can be opted for treatment of highly polluted industrial wastewater (HPIWW). All aforementioned technologies are low cost and clean, so they classified as environment friendly


181

• However, it is imperative that, HPIWW should be categorized and physically-chemically characterized before selection of the appropriate treatment technology. Respective parameters are; flow rate, toxicity, composition and concentration of the wastewater ingredients. • The spectrum of selection that satisfies cleanliness, low cost and compliance with legislations includes, but not limited to, the following: i. Anaerobic treatment methods The main features are satisfied in addition to simplicity in set-up, and operation, less sludge production, clean energy production and the high COD removal efficiency that can exceed 90% ii. Bio-sorption The process captures the dissolved heavy metal and/or toxic organics bio-materials which have the ability to attach and concentrate the metals ions or toxic organics. The main advantages of this treatment technology can be summarized in its cost effectiveness, only 0.5 $/m3. In addition, metal recovery is allowed, bio-sorbents are regenerative, moreover, a minimization of chemicals usage and no production of biological sludge. iii. Advanced Oxidation Processes (AOPs) These processes are ideal for treatment of non-biodegradable and recalcitrant organics in certain industrial wastewater. These industries produce soluble, refractory and toxic pollutants, herewith increasing the environmental fierce impacts. In such cases, the AOPs can minimize the treatment costs, by ca. 80%, furthermore AOPs can increase biodegradability and decrease toxicity and it can also destroy refractory pollutants by enhancing the mineralization. iv. Solar-AOPs Solar-AOPs could be applicable for treatment of HPIWW having bio-recalcitrant organic pollutants and also for disinfection for removing pathogens. Solar-AOPs are a cost effective treatment technologies, in many examples they save around 20% of the treatment costs in comparison with the UV-AOPs. Therefore, It can be concluded that, Solar-AOPs presented the state of the art clean and low cost treatment technologies for the IWW, particularly, in case of Egypt, where the sun shine period is one of the highest around the world (3650 hr./a).

References Abdelfattah, I. (2011), Treatment of Liquid Hazardous Waste and Highly-Loaded Industrial Wastewater by photo-Fenton process including Noxiousness Assessment, Stuttgarter Berichte zur Abfallwirtschaft. ISBN 978-3-8356-3245-5, Germany. Abdelfattah, I., Al Sayed, F., and Almedolab, A. (2016a), Removal of Heavy Metals from Wastewater Using Corn Cob, Research Journal of Pharmaceutical, Biological and Chemical Sciences, 7, 239-248. Abdelfattah, I., Ismail, A.A., Al Sayed, F., Almedolab, A., and Aboelghait, K.M. (2016b), Biosorption of heavy metals ions in real industrial wastewater using peanut husk as efficient and cost effective adsorbent, Environmental Nanotechnology Monitoring & Management, 6, 176-183. Abou-Elela, S.I., Fawzy, M.E., and El-Gendy, A.S. (2015), Potential of using Biological Aerated Filter as a Post Treatment for Municipal Wastewater, Ecological Engineering, 84, 53-57. Achak, M., Hafidi, A., Ouazzani, N., Sayadi, S., and Mandi, L. (2009), Low cost biosorbent “banana peel” for the removal of phenolic compounds from olive mill wastewater: Kinetic and equilibrium studies, Journal of Hazardous Materials, 166, 117-125. Adie, D.B., Okuofu, C.A., and Osakwe, C. (2012), Comparative Analysis of the Adsorption of Heavy Metals in Wastewater Using Borrassus Aethiopium and Cocos Nucifera, International Journal of Applied Science and Technology, 2(7), 314322.

182


Aksu, Z. and Yener, J. (2001), A comparative adsorption/biosorption study of monochlorinated phenols onto various sorbents, Waste Management, 21(8), 695-702. Amirnia, S. (2015), PhD-Thesis. Biosorption Processes for Removal of Toxic Metals from Wastewaters, The School of Graduate and Postdoctoral Studies, The University of Western Ontario, Canada. Ara, B., Shah, J., Jan, M.R., and Aslam, S. (2013), Removal of Metribuzin Herbicide from Aqueous Solution using Corn Cob, International Journal of Science, Environment and Technology, 2(2), 146-161. Arief, V.O., Trilestari, K., Sunarso, J., Indraswati, N., and Ismadji, S. (2008), Recent progress on biosorption of heavy metals from liquids using low cost biosorbents: Characterization, biosorption parameters and mechanism studies: a review, Clean Soil Air Water, 36, 937-962. Arunkumar, C., Perumal, R., and Lakshmi, S.N. (2014), Use of Corn cob powder as Low Cost Adsorbent for the Removal of Nickel (II) From Aqueous Solution, International Journal of Advanced Biotechnology and Research, 5(3), 325-330. Bakir, A., Mcloughlin, P. and Fitzgerald, E. (2010), Regeneration and reuse of a seaweed based biosorbent in single and multi-metal systems, Clean Soil Air Water, 38, 257-262. Bhatnagar, A., Minochaa, A.K., and Sillanp, M. (2010), Adsorptive removal of cobalt from aqueous solution by utilizing lemon peel as biosorbent, Biochemical Engineering Journal, 48, 181-186. Blanco, J., Malato, S., Fernández-Ibañez, P., Alarcón, D., Gernjak, W. and Maldonado, M.I. (2009), Review of feasible solar energy applications to water processes, Renewable and Sustainable Energy Reviews, 13(6-7), 1437-1445. Boucher, J., Steiner, L., and Marison, I.W. (2007), Bio-sorption of atrazine in the press-cake from oilseeds, Water Research, 41(15), 3209-3216. Bulut, Y. and Tez, Z. (2007), Removal of heavy metals from aqueous solution by sawdust adsorption, Journal of Environmental Science, 19, 160-166. Chan, P.Y., Gamal El-Din, M., and Bolton, J.R. (2012), A solar-driven UV/chlorine advanced oxidation process, Water Research, 46, 5672-5682. Chan, Y.J., Chong, M.F., Law, C.L., and Hassell, D.G. (2009), A review on anaerobic–aerobic treatment of industrial and municipal wastewater, Chemical Engineering Journal, 155, 1-18. Corseuil, H.X., Monier, A.L., Fernandes, M., Schneider, M.R., Nunes, C.C., do Rosario, M., and Alvarez, P.J.J. (2011), BTEX plume dynamics following an ethanol blend release: geochemical footprint and thermodynamic constraints on natural attenuation, Environmental Science and Technology, 45, 3422-3429. Durán, A., Monteagudo, J.M., Sanmart´ın, I., and Garc´ıa-D´ıaz, A. (2013), Sonophotocatalytic mineralization of antipyrine in aqueous solution, Applied Catalysis B: Environmental, 138-139, 318-325. Egila, J.N., Dauda, B.E.N., and Jimoh, T. (2010), Biosorptive removal of cobalt (II) ions from aqueous solution by Amaranthus hydridus L. stalk wastes, African Journal of Biotechnology, 9(48), 8192-8198. El-Awady, M.H., Abdelfattah, I., and Abo El-Magd, A. (2015), Reliable Treatment of Petroleum Processing Wastewater Using Dissolved Air Flotation in Combination with Advanced Oxidation Process, Egyptian Journal of Chemistry, 58(6), 609-624. El-Gohary, F.A. and Nasr, F.A. (1999), Cost-effective pre-treatment of wastewater, Water Scince and Technology, 39(5), 97-103. El-Sayed, G.O., Dessouki, H.A., and Ibrahim, S. (2011), Removal of Zn(II), Cd(II), Mn(II) from aqueous solution by adsorption on maize stalks, The Malaysian Journal of Analytical Sciences, 15, 8-21. Esparza, S.M., Sol´ıs, M.C., and Hernández, T.J.J. (2011), Anaerobic treatment of a medium strength industrial wastewater at low-temperature and short hydraulic retention time: a pilot-scale experience, Water Science and Technology, 64(8), 1629-1635. Fia, F.R.L., Matos, A.T., Borges, A.C., Fia, R., and Cecon, P.R. (2012), Treatment of wastewater from coffee bean processing in anaerobic fixed bed reactors with different support materials: performance and kinetic modeling, Journal of Environmental Management, 108, 14-21. Foletto, E., Battiston, S., Collazzo, G., Bassaco, M., and Mazutti, M. (2012), Degradation of leather dye using CeO2 –SnO2 nanocomposite as photocatalyst under sunlight, Water, Air and Soil Pollution, 223, 5773-5779. Freitas, A.M., Sirtori, C., Lenz, C.A., and Peralta Zamora, P.G. (2013), Microcystin-LR degradation by solar photo-Fenton, UV-A/photo-Fenton and UV-C/H2O2: a comparative study, Photochemical & Photobiological Sciences, 12, 696-702. ¨ Freundlich, H.M.F. (1906), Uber die Adsorption in Lösungen, Zeitschrift für Physikalische Chemie, 57, 385-470. Frontistis, Z., Drosou, C., Tyrovola, K., Mantzavinos, D., Fatta-Kassinos, D., Venieri, D., and Xekoukoulotakis, N.P. (2012), Experimental and modeling studies of the degradation of estrogen hormones in aqueous TiO2suspensions under simulated solar radiation, Industrial & Engineering Chemistry Research, 51, 16552-16563. Fujishima, A., Zhang, X., and Tryk, D.A. (2007), Heterogeneous photocatalysis from water photolysis to applications in environmental cleanup, International Journal of Hydrogen Energy, 32, 2664-2672. Garcia-Garcia, A., Martinez-Mirand, V., Martinez-Cienfuegos, I.G., Almazan-Sanchez, P.T., Castaneda-Juarez, M., and Linares-Hernandez, I. (2015), Industrial wastewater treatment by electrocoagulation–electrooxidation processes pow-


183

ered by solar cells, Fuel, 149, 46-54. Gonçalves, M.R., Costa, J.C., Marques, I.P., and Alves, M.M. (2012), Strategies for lipids and phenolics degradation in the anaerobic treatment of olive mill wastewater, Water Research, 46, 1684-1692. Gonçalves, M.R., Freitas, P., and Marques, I.P. (2012), Bioenergy recovery from olive mill effluent in a hybrid reactor, Biomass and Bioenergy, 39, 253-260. Hashim, M.A., Tan, H.N., and Chu, K.H. (2000), Immobilized marine algal biomass for multiple cycles of copper adsorption and desorption, Separation and Purification Technology, 19, 39-42. Ibrahim, M.B. (2013), Thermodynamics and adsorption efficiencies of maize cob and Sawdust for the remediation of toxic metals from wastewater, Journal of Geosciences and Environment Protection, 1, 18-21. Inel, O., Albayrak, F., and Askin, S. (1998), Cu and Pb Adsorption on Some Bentonitic Clays, Turkish Journal of Chemistry, 22, 243-252. Ismail, A.A., Abdelfattah, I., Atitar, M.F., Robben, L., Bouzid, H., Al-Sayari, S.A., and Bahnemann, D.W. (2015), Photocatalytic degradation of imazapyr using mesoporous Al2 O3 –TiO2 nanocomposites, Separation and Purification Technology, 145, 147-153. Ismail, A.A., Abdelfattah, I., Helal, A., Al-Sayari, S.A., Robben, L., and Bahnemann, D.W. (2016), Ease synthesis of mesoporous WO3–TiO2 nanocomposites with enhanced photocatalytic performance for photodegradation of herbicide imazapyr under visible light and UV illumination, Journal of Hazardous Materials 307, 43-54. Jalali, R., Ghafourian, H., Asef, Y., Davarpanah, S.J., and Sepehr, S. (2002), Removal and recovery of lead using nonliving biomass of marine algae, Journal of Hazardous Materials B92, 253-262. Jamil, N. and Munwar, M.A. (2009), Biosorbtion of Hg(II) and Cd(II) from waste water by using Zea Mays waste, Journal of the Chemical Society of Pakistan, 31(3), 362-369. Jonathan, Y., Hussaina, H., and Tijani, J.O. (2011), Application of adsorbent from Dum palm for the removal of Manganese (II), Zinc (II) and Copper (II) ions from aqueous solution, Journal of American Science, 7(10), 226-230. Langmuir, I. (1916), The constitution and fundamental properties of solids and liquids, Journal of the American Chemical Society, 38, 2221-2295. Lau, T.C., Ang, P.O., and Wong, P.K. (2003), Development of seaweed biomass as a biosorbent for metal ions, Water Science and Technology, 47, 49-54. Lemić, J., Kovacević, D., Tomasević-Canović, M., Kovacević, D., Stanić, T., and Pfend, R. (2006), Removal of atrazine, lindane and diazinone from water by organo-zeolites, Water Research 40(5), 1079-1085. Malato, S., Fernandez-Ibanez, P., Maldonado, M.I., Blanco, J., and Gernjak, W. (2009), Decontamination and disinfection of water by solar photocatalysis: Recent overview and trends, Catalysis Today 147, 1-59. Marcelino, R.B.P., Queiroz, M.T.A., Amorim, C.C., Leão, M.M.D., and Brites, F.F. (2015), Solar energy for wastewater treatment: review of international technologies and their applicability in Brazil, Environmental Science and Pollution Research, 22(2), 762-773. Mar´ın, P., Alkalay, D., Guerrero, L., Chamy, R., and Schiappacasse, M.C. (1999), Design and startup of an anaerobic fluidized bed reactor, Water Science and Technology, 40(8), 63-70. Michael, I., Hapeshi, E., Ace, N.J., Perez, S., Petrovic, M., Zapata, A., Barcelo, D., Malato, S., and Fatta-Kassinos, D. (2013), Light-induced catalytic transformation of ofloxacin by solar Fenton in various water matrices at a pilot plant: mineralization and characterization of major intermediate products, Science of Total Environment, 461-462, 39-48. Mico, M.M., Bacardit, J., Malfeito, J., and Sans, C. (2013), Enhancement of pesticide photoFenton oxidation at high salinities, Applied Catalysis B: Environmental, 132-133, 162-169. Monteagudo, J.M., Duran, A., Corral, J.M., Carnicer, A., Frades, J.M., and Alonso, M.A. (2012), Ferrioxalate-induced solar photo-Fenton system for the treatment of winery wastewaters, Chemical Engineering Journal, 181-182, 281-288. Munter, R. (2001), Advanced oxidation processes-current status and prospects, Proceedings of the Estonian Academy of Sciences, 50(2), 59-80. Muthusamy, P., Murugan, S., and Manothi, S. (2012), Removal of Nickel ion from industrial wastewater using maize cob, ISCA Journal of Biological Sciences, 1(2), 7-11. Musapatika, E.T., Singh1, R., Moodley, K., Nzila, C., Onyango, M.S., and Ochieng, A. (2012), Cobalt removal from wastewater using pine sawdust, African Journal of Biotechnology, 11(39), 9407-9415. Nascimento, C.A.O., Teixeira, A.C., Guardani, R., Quina, F.H., Chiavone-Filho, O., and Braun, A.M. (2007), Industrial Wastewater Treatment by Photochemical Processes Based on Solar Energy, Journal of Solar Energy Engineering, 129, 45-52. Nasr, F.A., Badr, N.M., Doma, H.S., and El-Shafai, S.A. (2006), Chemical industry wastewater treatment, The Environmentalist, 26(1), 31-39. Nasr, F.A., Doma, H.S., Abdel-Halim, H.S., and El-Shafai, S.A. (2007), Chemical industry wastewater treatment, The Environmentalist, 27(2), 275-286. Nezamzadeh-Ejhieh, A. and Banan, Z. (2011), A comparison between the efficiency of CdS nanoparticles/zeolite A and

184


CdO/zeolite-A as catalysts in photodecolorization of crystal violet, Desalination, 279, 146-15. Pera-Titus, M., Garcia-Molina, V., Banos, M.A., Gimenez, J., and Esplugas, S. (2004), Degradation of chlorophenols by means of advanced oxidation processes: a general review, Applied Catalysis B: Environmental, 47, 219-256. Pérez, J.A.S., Lopez, J.L.C., and Malato, S. (2013), Economic evaluation of a combined photo-Fenton/MBR process using pesticides as model pollutant. Factors affecting costs, Journal of Hazardous Materials, 244-245, 195-203. Petrovic, M., Radjenovic, J., and Barcelo, D. (2011), Advanced oxidation processes (AOPs) applied for wastewater and drinking water treatment. Elimination of pharmaceuticals. In: The Holistic Approach to Environment, 1, 63-74. Perez, M., Romero, L.I., and Sales, D. (1999), Anaerobic thermophilic fluidized bed treatment of industrial wastewater: effect of F:M relationship, Chemosphere, 38(14), 3443-3461. Prieto-Rodriguez, L., Oller, I., Klamerth, N., Aguera, A., Rodriguez, E.M. and Malato, S. (2013), Application of solar AOPs and ozonation for elimination of micropollutants in municipal wastewater treatment plant effluents, Water Research, 47, 1521-1528. Quan, X., Wang, W., Yang, Z., Lin, C. and He, M. (2007), Continuous removal of aromatic hydrocarbons by an AF reactor under denitrifying conditions, World Journal of Microbiology and Biotechnology, 23(12), 1711-1717. Rajagopal, R., Saady, N.M.C., Torrijos, M., Thanikal, J.V., and Hung, Y. (2013), Review Sustainable Agro-Food Industrial Wastewater Treatment Using High Rate Anaerobic Process, Water, 5, 292-311. Rajeshwari, K.V., Balakrishnan, M., Kansal, A., Lata, K. and Kishore, V.V.N. (2000), State of the art of anaerobic digestion technology for industrial wastewater treatment, Renewable and Sustainable Energy Reviews, 4, 135-156. Rajinikanth, R., Ganesh, R., Escudie, R., Mehrotra, I., Kumar, P., Thanikal, J.V. and Torrijos, M. (2009), High rate anaerobic filter with floating supports for the treatment of effluents from small-scale agro-food industries, Desalination and Water Treatment, 4, 183-190. Robert, D. and Malato, S. (2002), Solar photocatalysis: a clean process for water detoxification, Science of the Total Environment, 291(1-3), 85-97. Rocha, E.M.R., Vilar, V.J.P., Fonseca, A.L., Saraiva, I. and Boaventura, R.A.R. (2011), Landfill leachate treatment by solar-driven AOPs, Solar Energy, 85, 46-56. Rodriguez, E.M., Fernandez, G., Klamerth, N., Maldonado, M.I., Alvarez, P.M. and Malato, S. (2010), Efficiency of different solar advanced oxidation processes on the oxidation of bisphenol A in water, Applied Catalysis B: Environmental, 95, 228-237. Saien, J. and Nejati, H. (2007), Enhanced photocatalytic degradation of pollutants in petroleum refinery wastewater under mild conditions, Journal of Hazardous Materials, 148, 491-495. Sari, A. and Tuzen, M. (2009), Kinetic and equilibrium studies of biosorption of Pb(II) and Cd(II) from aqueous solution by macro fungus (Amanita rubescens) biomass, Journal of Hazardous Materials, 164(2-3), 1004-1011. Sari, A., Tuzen, M., Uluozlu, O.D., and Soylak, M. (2007), Biosorption of Pb(II) and Ni(II) from aqueous solution by lichen (Cladoniafurcata) biomass, Biochemical Engineering Journal, 37(2), 151-158. Sentürk, E., Ince, M., and Engin, G.O. (2010), Treatment efficiency and VFA composition of a thermophilic anaerobic contact reactor treating food industry wastewater, Journal of Hazardous Materials, 176(1-3), 843-848. Sharon, H. and Reddy, K.S. (2015), A review of solar energy driven desalination technologies, Renewable and Sustainable Energy Reviews, 41, 1080-1118. Stasinakis, A. (2008), Use of selected advanced oxidation processes (AOPs) for wastewater treatment-a mini review, Global Nest Journal, 10, 376-385. Sud, D., Mahajan, G., and Kaur, M.P. (2008), Agricultural waste material as potential adsorbent for sequestering heavy metal ions from aqueous solutions – A review, Bioresource Technology, 99, 6017-6027. Sun, L., Wan, S., Yu, Z., Wang, Y., and Wang, S. (2012), Anaerobic biological treatment of high strength cassava starch wastewater in a new type up-flow multistage anaerobic reactor, Bioresource Technology, 104, 280-288. van Haandel, A. and van der Lubbe, J. (2012), (Book) Handbook of Biological Wastewater Treatment: Second Edition. IWA publishing books ISBN 13: 9781780407753. Vilar, V.J.P., Capelo, S.M.S., Silva, T.F.C.V., and Boaventura, R.A.R. (2011), Solar photoFenton as a pre-oxidation step for biological treatment of landfill leachate in a pilot plant with CPCs, Catalysis Today, 161, 228-234. Won, S.G., Lau, A.K. (2011), Effects of key operational parameters on biohydrogen production via anaerobic fermentation in a sequencing batch reactor, Bioresource Technology, 102(13), 6876-6883. Yan, C., Yan, G.Y., Xue, P., Wei, Q., and Li, Q. (2010), Competitive effect of Cu(II) and Zn(II) on the biosorption of lead(II) by Myriophyllum spicatum, Journal of Hazardous Materials, 179, 721-728. Zhang, T., Wang, X., and Zhang, X. (2014), Review Article: Recent Progress in TiO2 Mediated Solar Photocatalysis for Industrial Wastewater Treatment, International Journal of Photoenergy, 2014, 1-12. Zheng, S., Yang, Z., Jo, D.H., and Park, Y.H. (2004), Removal of chlorophenols from groundwater by chitosan sorption, Water Research, 38, 2315-2322. Zheng, S., Yang, M., Yang, Z., and Yang, Q. (2005), Biomass production from glutamate fermentation wastewater by the co-culture of Candida halophila and Rhodotorula glutinis, Bioresource Technology, 96, 1522-1524.