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Applied Water Science Volume 1: Fundamentals and Applications Inamuddin
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Library of Congress Cataloging-in-Publication Data
ISBN 978-1-119-72473-5
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3.4
4
A. Biswas and S. Chakraborty
4.1
4.2
4.3
Jafarinejad
5.1
Slimane Merouani and Oualid Hamdaoui
6.1
7
6.5
6.6
6.6.1
6.6.2
6.6.3
6.6.4
6.6.5
6.7
6.8
Ali Khadir, Arman N. Ardestani, Mika Sillanpää and Shreya Mahajan
Rosangela R. Dias, Mariany C. Deprá, Leila Q. Zepka and Eduardo Jacob-Lopes
13.4
Jain,
D. Mohammady Maklavany, Z. Rouzitalab, S. Jafarinejad, Y. Mohammadpourderakhshi and A. Rashidi 15.1
15.2.5
15.2.6
15.3
15.3.4
15.4
18
18.3
18.5
S. Ghosh and S. Chakraborty 19.1
Preface
The high rate of industrialization around the world has led to an increase in the rate of anthropogenic activities which involves the release of different types of contaminants into the aquatic environment generating high environmental risks, which could affect health and socio-economic activities if not treated properly. There is no doubt that the rapid progress in improving the water quality and management has been motivated by the latest developments in green chemistry. Over the past decade, sources of water pollutants and the conventional methods used for the treatment of industrial wastewater treatment has flourished. Water quality and its adequate availability have been a matter of concern worldwide particularly in developing countries. According to a World Health Organization (WHO) report, more than 80% of diseases are owing to the consumption of contaminated water. Heavy metals are highly toxic that are a potential threat for water, soil, and air, their consumption in higher concentrations provided hazardous outcomes. The water quality is usually measured keeping in mind chemical, physical, biological, and radiological standards. The discharge of the effluent by industries contains heavy metals, hazardous chemicals, and a high amount of organic and inorganic impurities those can contaminate the water environment, and hence, human health. Therefore, it is our primary responsibility to maintain the water quality in our respective countries.
This book provides understanding, occurrence, identification, toxic effects and control of water pollutants in aquatic environment using green chemistry protocols. It focuses on water remediation properties and processes including industry-scale water remediation technologies. This book covers recent literature on remediation technologies in preventing water contamination and its treatment. Chapters in this book discuss remediation of emerging pollutants using nanomaterials, polymers, advanced oxidation processes, membranes, and microalgae bioremediation, etc. It also includes photochemical, electrochemical, piezoacoustic, and ultrasound techniques. It is a unique reference guide for graduate
students, faculties, researchers and industrialists working in the area of water science, environmental science, analytical chemistry, and chemical engineering.
Chapter 1, brief introduces pharmaceuticals’ and antibiotics’ pollution. Different methods for antibiotic removal from aqueous environments are presented. The performance of various technologies is discussed.
Chapter 2 describes the application of adsorbents in water remediation. These are natural and low-cost materials including bark, feather, husks, leaves, peels, rinds, seeds, stones, spent coffee and tea. The often neglected issue related to the disadvantages and challenges of such materials’ usage is thoroughly discussed.
Chapter 3 focuses on various types of reactors, which are used in water remediation. The models of multiphase flows are described and an overview of modeling and simulation of water remediation reactors are presented. Furthermore, the design of new reactors with modern geometry are discussed.
Chapter 4 reviews the iMETL and technology which is to integrate constructed wetland with microbial electrochemical technology. The synergy between these two separate technologies, the recent trend of application, its potential for industrial wastewater treatment and the challenges for scaling up the system and future scope is also discussed.
Chapter 5 focuses on forward osmosis technology as an emerging membrane process for the treatment of petroleum industry wastewater. Also, recent advances in forward osmosis membranes challenges ahead and future perspective are briefly discussed.
Chapter 6 presents details about UV/periodate (IO4 ) process that is one of the recent advanced oxidation technologies for water treatment. It discusses fundamental aspects of the photochemical decomposition of periodate in water and addresses factors influencing the process efficiency. The recent works on the degradation of organic pollutants by this process are also reviewed.
Chapter 7 attempts to introduce a various biological-based technique for leachate treatment. Sanitary landfills are one of the modern technologies for wastes management and control. However, the generation of landfill leachate is a great issue regarding landfills. Biological treatment is one of the most popular practices for leachate treatment.
Chapter 8 discusses the role of metal-organic framework nanoparticles and their various adsorption applications in removal of different categories of contaminants of water such as heavy metal ions, organic, inorganic and radioactive materials. It also describes the metal-organic framework nano particles-based membrane technology for water remediation. Toxicity,
Preface xix
safety and environmental impacts of metal-organic framework nanoparticles are also highlighted.
Chapter 9 focuses on the application of metal-organic frameworks in removing heavy metals. The first part of the chapter discusses the existence of heavy metals in the environment and common removal technologies. The second part discusses the application of metal-organic frameworks and metal-organic frameworks-based hybrid materials for heavy metals removal.
Chapter 10 provides information about the potential of microalgae as a biotechnological tool for polluted environments’ bioremediation. Mechanisms involved in bioremediation using microalgae are described. The main focus is given on the microalgae bioremediation ability to a series of inorganic, organic, and emerging pollutants. Products generated from the bioremediation are also included.
Chapter 11 describes the hybrid advanced oxidation based photocatalytic techniques for effective and efficient treatment of contaminated water for achieving disinfected water. It also explains the merits and demerits of various hybrid-techniques for treating the wastewater discharged from various industries.
Chapter 12 elaborates various methods of phytoremediation as an ecofriendly alternative to sequestrate the metal ions and many alternative methods’ risks and opportunities. This chapter discusses not only the best and promising solutions to heavy metal contamination in soil and water using plants but also economic alternatives.
Chapter 13 discusses the role of ultrasound in water remediation through physical and chemical mechanisms ranging from acoustic streaming to sonochemistry. It particularly focuses on continuous flow sonochemistry, addresses technological feasibility and highlights the place of micro-flow sonoreactors applied to water remediation. Their scalability concerns are then discussed with regards to numbering up and scaling out strategies.
Chapter 14 explains the principles involved in the advanced oxidation process. This chapter also summarizes the commonly utilized advanced oxidation process such as Fenton, peroxination, sonolysis, ozonation, ultraviolet radiation-based, and photon-Fenton process for the water as well as wastewater remediation.
Chapter 15 details the application of copper oxide-based catalysts in advanced oxidation processes. A brief overview of catalytic advanced oxidation processes, recent advances and applications of copper oxide-based catalysts in advanced oxidation processes, and future perspectives are discussed.
Preface
Chapter 16 discusses the applicability of biochar absorbents for pharmaceuticals’ removal. The operational parameters and isotherms/kinetics models are discussed in details.
Chapter 17 discusses various sources of agricultural wastewater and its composition. Several biological treatment methods such as anaerobic, aerobic digestion, bioremediation of pesticides and microalgae usage for the treatment of agro-industrial effluents are reviewed in detail. The primary focus is given to bioremediation technologies and future outlook for wastewater treatment.
Chapter 18 focuses on the source, classification and threats of different emerging pollutants like pharmaceuticals, pesticides, surfactants, microplastics, and endocrine disrupters to human and environment along with the efficient biological treatments like aerobic granulation, constructed wetland and other bioreactor mediated techniques with mitigation policies.
Chapter 19 highlights various approaches to remediate different wastewater samples. Low-cost, renewable, agricultural and processed industrial agriculture waste materials as bio-adsorbents for the elimination of several pollutants from wastewater is presented.
1 Insights of the Removal of Antibiotics From Water and Wastewater: A Review on Physical, Chemical, and Biological Techniques
Ali Khadir1*, Amin M. Ramezanali2, Shabnam Taghipour3 and Khadijeh Jafari4
1Young Researcher and Elite Club, Yadegar-e-Imam Khomeini (RAH) Shahre Rey Branch, Islamic Azad University, Tehran, Iran
2School of Civil Engineering, College of Engineering, University of Abbaspour, Tehran, Iran
3Department of Civil Engineering, Sharif University of Technology, Tehran, Iran
4Environmental Science and Technology Research Center, Department of Environmental Health Engineering, School of Public Health, Shahid Sadoughi University of Medical Sciences, Yazd, Iran
Abstract
Pharmaceuticals, particularly antibiotics, are rightly regarded as one of the major emerging contaminants of the environment and there is increasing concern over their continuous presence in the aqueous solutions. Extensive research has shown that these compounds have been detected in fresh water of many countries. In this chapter, a brief introduction on pharmaceuticals and antibiotic pollution and also different common methods for antibiotic abatement in aqueous solutions has been studied. The performance of technologies such as membrane bioreactors, aerobic granular sludge, activated carbons, magnetic nanoparticles, Fenton processes, Peroxone, photocatalytic degradation, and electrocoagulation has also been discussed. Each method has its own advantages and disadvantages in which at present no sole system might be the best one.
Drugs and their related compounds have been initially utilized to treat living creatures and since their discovery they have rescued lives of many people and animals. In fact, living without drugs seems to be impossible, particularly under present situation that humans are dealing with wide range of contaminants during their daily life. However, rapid population growth, continuous agricultural and industrial development, and establishment of countless pharmaceutical companies have made drugs as a hazardous health components for ecosystem [1,2]. Briefly, these compounds are persistent, recalcitrant, and toxic and many organisms are not able to metabolize and adsorb such compounds [1]. Effluent and wastes by pharmaceutical manufacturing companies, municipal wastewaters, and human/animal excretion are of the main pathways of pharmaceutical compounds entrance the environment [3,4]. Approximately 50–80, 80–90, and 15–30% of ciprofloxacin, tetracycline and sulfamethoxazole are excreted through urine and feces, respectively [5,6]. Unfortunately, present wastewater treatment plants could not remove pharmaceutical completely because of the lack of facilities and technologies. It must be considered that wastewater treatment plants act an integral role for pollution release unless they have proper treatment technique [7,8]. Fernández-López et al. [9] investigated the removal of four pharmaceuticals in different five treatment plants (Figure 1.1), and they reported that they have detected the target pollutants in the both influent and effluent of the treatment plants. Carbamazepine and naproxen were the most abundant compounds. Palli et al. [10] also found that pharmaceuticals were detected in the influent of wastewater treatment plants of Tuscany (Italy) in which acetaminophen (3,914 ± 2,620 ng/L), diclofenac (2,065 ± 739 ng/L) and amoxicillin (2,002 ± 2,170 ng/L) were the most concentrated followed by atenolol, ketoprofen, clarithromycin, carbamazepine, doxycycline and 17-β-estradiol. Their finding declared that some components had been removed well, but some of the others have exhibited partly elimination. Bagnis et al. [11] observations showed that wastewater, landfill leachate and agriculture were the sources of the presence of pharmaceuticals in Nairobi river. Considering these results, pharmaceuticals are generally detected in the effluent of conventional wastewater treatment plants, and to prevent the pollution spread, a full recognition of these system along with other advanced ones are vitally important.
Generally, pharmaceuticals are categorized into different classes including analgesics, antibiotics, psychiatric drugs, anti-hypertensives, beta-blockers,
System 1 (CAS-DS+L+CF+SF+UV )
System 2 (CAS-CI)
System 3 (MBR+UV )
System 4 (EAAS+CF+SF+UV )
System 5 (EAAS+CF+SF+UV+CI)
Figure 1.1 The schematic system of various treatment systems. Reprinted and reproduced with permission from Ref. [9].
hormones, contrast media, anti-diabetics, anti-viral, and anti-cancer drugs. Among antibiotics, antimicrobial drugs leading to bacterial growth inhibition, are important environmental pollutants due to their huge consumption. From 2000 to 2010, global antibiotic consumption promoted by 36%, signifying a forthcoming serious environmental issue [12]. Previous studies have confirmed that approximately 70 antibiotics have been detected in various media such as waters, soil, and sediment [13–16]. According to the available reports, in fresh waters of many countries such as Ghana, South Africa, Kenya, Nigeria, Mozambique, USA, Brazil, Canada, Latin America, Australia, Iran, China, Taiwan, Japan, Korea, UK. France, Spain, Germany, Italy, etc. antibiotic compound have been detected, indicating that antibiotic pollution may dominate the entire world, requiring nation and international plans to cease their future consequences [6]. Toxicity, persistence, carcinogenicity, DNA damage and lymphocyte mutagenicity, increasing human allergy, lower biodegradability, spread of antibiotics resistance bacteria and causing undesirable effects on humans and animals are some of the main hazardous side effects of the antibiotic spread [17–19]. Thus, it is obligatory to implement proper treatment systems to prevent further antibiotic release in the ecosystem.
Different treatment methods which have been applied for treatment of oily wastewaters are antibiotic contaminated waters include biological, chemical, and physical processes. In biological treatment (aerobic and
anaerobic) microorganisms are employed to treat wastewater under the presence or absent of oxygen. Activated sludge is one of the oldest bioreactor that has fluctuations in the removal efficiency of persistent compounds. Chemical methods such as advanced oxidation processes (AOPs) often decompose antibiotics into simpler molecules but this technology is very complex and expensive. However, it has generally high removal efficiency under appropriate operation. Physical techniques are one of the most effective methods of removing antibiotics from aquatic environments. Owing to generation of less toxic byproducts and low operational costs, adsorption is considered as a simple, practical, and effective method among other physical processes. In recent years, combination of several methods has been developed to increase the removal efficiency however these methods require further scrutiny to optimize the process. Considering both antibiotic pollution and treatment methods, the aim of present chapter, is studying application of various technology for antibiotics pollution abatement from aqueous solutions.
1.2
Antibiotic Removal Methods
1.2.1 Aerobic Biological Treatment
Aerobic wastewater treatment involves using oxygen for degradation of the soluble and colloidal organic matters into carbon dioxide, ammonia, energy, water, and new cells by means of heterotrophic and autotrophic microorganisms. Heterotrophs are organisms that require organic carbon supply for growth, and those which utilize inorganic carbon such as carbon dioxide are known as autotrophic microorganisms. A mix of these organisms as a unite culture can degrade compounds effectively. Since supplying oxygen is costly, aerobic processes are feasible if the COD of the input wastewaters is less than 1,000 mg/L [20,21]. In high-strength effluent such as industrial wastewater (e.g. pharmaceutical companies effluents), a hybrid system of anaerobic/aerobic could bring satisfactory results in terms of organic matters removal.
After the advent of membrane processes in 1960s like microfiltration, ultrafiltration, nanofiltration, and reverse osmosis, the development of membrane bioreactors (MBRs) were of great attention. MBRs are hybrid bioreactors of membrane filtration and activated sludge, using a physical–biological treatment system which are effective for municipal and industrial wastewaters [22]. Figure 1.2 illustrates the schematic of two configurations of MBRs which are side-stream MBR and submerged MBR. The main
benefits of MBRs over activated sludge processes are their less required space for operation and also their ability to eliminate distinctive compositions of wastewaters [23]. Bentmen et al. [24] proved that MBR effluent has better quality than single activated sludge process and the mean BOD, COD, and turbidity removal was greater than 90% [25]. Sahar et al. (2011) found that MBRs could result in about 15–42% higher removal efficiency in comparison to conventional activated sludge [9]. In the drug production centers using MBR technology for the treatment of their wastewater, high removal of COD and BOD has been reported [23]. For example, with a capacity of 1 m3/day for MBR operated at a pharmaceutical center in Taiwan, 95% COD and 99% BOD were eliminated. The initial values of COD and BOD were 800–11,800 and 100–6,350 mg/L, respectively [26]. Song et al. [27] successfully used biofilm MBRs for simultaneous removal of COD, nitrogen and veterinary antibiotics from digested piggery wastewater. The initial concentration of COD and total nitrogen (TN) was 1,101 ± 185 and 1,492 ± 132 mg/L, respectively. They found that COD/TN ratio played an important role that could highly affect the quality of effluent. Under optimum ratio of COD/TN (2.3 ± 0.5), 92.1 and 97.1% of COD and NH -N 4 + were removed, respectively. Also, the effect of hydraulic retention time (HRT) on the removal of 30.41 µg/L antibiotic was studied and observed that by decreasing HRT from 5 to 1 d, the removal efficiency reduced from 86.8 to 45.3%, respectively. However, Prasertkulsak et al. [28] observed complete removal of ibuprofen, 17β-Estradiol and triclosan at days 42 and 76.
Blower
Figure 1.2 Two configurations of MBRs. Reproduced with permission from Ref. [31].
MBRs have a unique advantage compared to many biological systems that make this technique to be extensively utilized. Fluctuations in the characteristics of the influent could deteriorate the quality of the treated water since many biological systems could not endure such variations. However, MBRs have proved their appropriate performance even under such circumstances. Zhu et al. [29] expressed that 100 µg/L sulfamethoxazole and tetracycline hydrochloride could not affect the performance of the systems and pollutants were removed perfectly. Even at antibiotic dosage up to 2,000 µg/L, COD and ammonia removal were not affected; however, denitrification was hindered. In another investigation, it was found that after tetracycline addition to the system, COD removal was approximately the same (changed from 92 to 88%), and of ammonium it was constant (99%) [30]. Similar to Zhu et al. [29] finding, denitrifies were affected by the antibiotic toxicity.
Activated sludge is one of the oldest biological wastewater treatment system that has been extensively utilized over a century for treatment of various contaminants [31, 32]. In the time of invention, it is fair to say that activated sludge was a breathtaking technology and paved the way for further development. By population growth and generation of countless recalcitrant organic matters, activated sludge may face some limitations such as installation of multiple units for carbon, nitrogen and phosphorous removal, flow recirculation, low biomass concentrations in the aeration tank, the necessity of clarifier to separate solids, large area requirement, much energy required for oxygen supply, and poor settling (may be because of sludge bulking) [33–35]. It has been more than two decades from the first usage of aerobic granular sludge and the findings demonstrate that it could be a novel and promising development in the field of biological treatment, and it has been predicted that aerobic granular sludge will overtake activated sludge [36,37]. Aerobic granules consist of highly compacted microbial aggregates containing millions of microorganisms per gram of biomass that their densities are much higher than that of conventional activated sludge. Tolerance to toxicity, high biomass retention, withstand at high organic loading, lower operational cost, less electricity requirement, and smaller land requirement (in comparison to activated sludge) are some of the main advantages of aerobic granular sludge over conventional activated sludge [38]. Table 1.1 compares some other features of aerobic granular sludge and conventional activated sludge. Figure 1.3 illustrates a schematic diagram of conventional activated sludge and aerobic granular sludge. Researchers tried to employ such a system for antibiotics removal.
Wang et al. (2019) studied the removal and fate of 5 antibiotics (Cin = 29.4–44.1 µg/l) and antibiotic-resistant bacteria (Cin = 80.9 × 104−111.6 × 104 CFU/ml) from piggery wastewater by aerobic granular sludge. The total
Antibiotic Abatement in Aqueous Solutions 7
Table 1.1 Comparison of aerobic granular sludge and conventional activated sludge.
Shape Regular and spherical Irregular and Filamentous
Layers
Aerobic, anoxic and Anaerobic Aerobic
Tolerability High Low
EPS production High Low
Figure 1.3 Schematic diagram of (a) conventional activated sludge and (b) aerobic granular sludge. Reproduced with permission from Ref. [35].
antibiotics and antibiotic-resistant bacteria removal were up to 88.4±4.5 and 89.4±3.3%, respectively. Moreover, 62.5 and 32.3% of total antibiotics were degraded and adsorbed by aerobic granular sludge, respectively. Bioadsorption and biodegradation were introduced as the main removal pathway of the drugs. In this study COD, NH3-N, and TN removal
efficiencies were 98.0, 97.0, and 92.4%, respectively. Also, presence of antibiotics did not affect the performance of the system [39]. In another study, tetracycline injection at μg/L level did not affect the removal efficiency of COD and nitrogen, but microbial community and diversity of aerobic granular sludge were altered. Removal efficiency of aerobic granular reactor for tetracycline at initial concentrations of 100 and 500 μg/L were equal to 84.4 and 94.2%, respectively [40]. Kang et al. [41] verified that 2 μg/L sulfamethoxazole could not affect the performance of aerobic granular sludge and conventional suspended activated sludge; however, within two months’ bacterial community of both biological systems were altered. In addition, sulfamethoxazole (Cin = 2 µg/L) showed higher elimination (84 ± 8%) by granular sludge than suspended sludge (73 ± 10%). Wang et al. (2018) studied degradation of 300 µg/L oxytetracycline in an aerobic granular sludge sequencing batch reactor. Until day 33 oxytetracycline removal curve exhibited an increasing trend, and then remained constant (89%), and for COD, NH -N 4 + , and total phosphorous it was 8.0, 90.0 and 97.9%, respectively. The microbial community was also altered after oxytetracycline addition [42]. Based on the reported results, aerobic granular sludge is a suitable and effective technique for antibiotics removal with high removal efficiency; however, the changes in the microbial community must be considered well to prevent further issues.
1.2.2
Anaerobic Biological Treatment
Anaerobic process, as its name defines, is a biological wastewater treatment technique to degrade organic matters in the absence of a free or molecular oxygen source with the contribution of anaerobic microorganisms. Anaerobic process is different from anoxic process since it is a reducing media with greatly negative values of oxidation reduction potential. In this environment, nitrate and sulfate are reduced to ammonia (or nitrogen gas) and hydrogen sulfide, respectively. Bacterial community and chemical–biological reactions of anaerobic processes are much more complicated than aerobic processes because there are several pathways for removal, and still there are few reactions that are not fully understood. Besides its complex nature in both operation and dominant organisms, it has been nominated as a promising wastewater treatment technology.
It is considered that Assyrians were the first employed anaerobic process to heat their water and bath. After that, this process was utilized to digest human and solid wastes. Nowadays, anaerobic application is widely utilized for treatment of industrial effluents, especially those
having recalcitrant organic matters. Such favorability might be attributed to advantages of anaerobic processes over aerobic ones. Some of these benefits are [43]:
1. No aeration is required, so it consumes less energy compared to biological systems.
2. Nutrient balance in aerobic system is vitally important; however, in anaerobic system less nutrient amount is required.
3. Methane (or so-called energy) is a valuable end product of anaerobic processes, which could compensate a part of treatment costs. In aerobic, no valuable product is produced.
4. Sludge management in every biological treatment system is of great concern, and it is tried to reduce its volume as much as possible. Fortunately, anaerobic process produces only 20% of sludge that of aerobic process.
5. Aerobic systems cannot tolerate high organic loading rate since they need a great amount of oxygen to degrade organic matters which is not cost effective. But, anaerobic processes can treat effluents owning high organic matters.
6. Less space is occupied in anaerobic systems in comparison to aerobic processes.
Above excellences have made anaerobic processes a feasible and efficient treatment system. Considering all these, anaerobic also has some disadvantages that might impede its application. Firstly, quality of treated wastewater could not follow the discharge limit for ultimate disposal. Owning to this fact, it is suggested that anaerobic systems should be coupled with other aerobic processes. Secondly, biomass synthesis rate is not as fast as aerobic process, resulting in longer start-up time. Microbial community in anaerobic processes is sensitive to environmental conditions (especially methanogens) and changes in parameters like pH and temperature could significantly reduce the performance of the system. Aerobic processes are capable of enduring these changes to some extent.
Briefly, organic matters experience some sequential steps to degrade into final products of anaerobic processes which are mainly methane and carbon dioxide. Figure 1.4 depicts the degradation stages of organic matter in anaerobic processes. Hydrolysis, the first stage of anaerobic reactions, could convert large molecules such as proteins, carbohydrates, and lipids into simpler compounds like sugars, amino acids, and fatty acids. This step might be slow depending on the size of the organic matter and operational parameters like pH and temperature [44]. After the formation of
Figure 1.4 Degradation stages of organic matter in anaerobic processes. Reproduced with permission from Ref. [54].
soluble organic matters, they are changed into volatile fatty acids via acidogenic bacteria [45]. Acetogenesis is the third stage involving the production of acetate along with water and carbon dioxide. Approximately 2–3 h is required for bacterial growth and biochemical conversion rate in this step [46]. Uncontrolled production of volatile fatty acids may cause a drop in pH value that could impede methane production. It is recommended to maintain the volatile fatty acids/alkaline ratio lower than 0.3 [47,48]. Methanogenesis is the final step in anaerobic degradation of carbon in which acetic acid and carbon dioxide are converted into methane (Equations (1.1–1.2)). By accomplishment of these reactions at the optimum pH of 6.8–7.2, organic matters are stabilized/removed [46]. Acetoclastic methanogens (72%) are the main responsible for the major CH4 generation compared to hydrogenotrophic methanogens [46,49]. But, they grow too slowly [50] and are more sensitive to environmental parameters (such as temperature, pH, and ammonia) in comparison with hydrogenotrophic methanogens [51,52]. Thus, a balance between hydrogenotrophic methanogens and acetoclastic methanogens must be
