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hello i want you to paraphrase for me chapter 1 ONLY to avoid plagiarism because my friend is using the same document, i will send the document below it will include 2 chapters ignore chapter 2 just paraphrase chapter 1 (Background, limitation of constructed wetland and the problem statement)
and the references are below if you need them to refer to (might help)
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CONSTRUCTED WESTLAND FOR WASTEWATER TREATMENT
Constructed Westland for Wastewater Treatment
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CONSTRUCTED WETLANDS FOR WASTEWATER TREATMENT
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Table of Contents
Background ..................................................................................................................................... 4
Limitations of Constructed Wetlands ......................................................................................... 6
Problem Statement .......................................................................................................................... 7
Objectives ....................................................................................................................................... 8
Literature Review ........................................................................................................................... 9
Domestic , Municipal and Industrial Wastewater ........................................................................... 9
Conventional Wastewater Treatment ............................................................................................ 11
Conventional Wastewater Treatment Process ........................................................................... 11
Primary Treatment ................................................................................................................. 11
Secondary Treatment ............................................................................................................. 12
Tertiary Treatment ................................................................................................................. 12
Constructed Wetlands .................................................................................................................. 13
Advantages of Constructed Wetlands ...................................................................................... 14
The Main Benefits and Outcomes of the Constructed Wetlands .............................................. 15
Types of Constructed Wetlands ................................................................................................ 15
Components of Constructed Wetlands ...................................................................................... 16
Water ..................................................................................................................................... 16
Substrates, Sediments, and Litter .......................................................................................... 17
Vegetation .............................................................................................................................. 17
Microorganisms ..................................................................................................................... 18
Animals .................................................................................................................................. 19
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References ................................................................................................................................. 21
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Background
Water is one of the essentials that contribute primarily to the sustenance of life for both
living things and non-living things. Water is “life” meaning the existence of all inhabitants on
Earth is dependent on this resource. Water supports both natural and human-made. Therefore,
human beings should safeguard all the sources of water across the globe because water is indeed
a crucial element that they cannot manage to live without. Despite the fact that water is essential
for life sustenance water pollution has become a significant threat to the water source in the
whole world. Industrial wastes and the exhaust fumes are the major contributors of water pollution across the globe. The growth in industrial development across the world has caused more
wastes to be released in the water bodies. Wastes from single household activities, municipal
wastes and untreated industrial wastes discharged in the water sources have put human beings
into a risk of contracting water-borne diseases, environmental degradation and even endanger the
marine life. In general, the discharging of untreated industrial wastes, municipal and single
household wastes puts the lives of all living and non-living things at risk (Postel, 2000).
Water pollution control mechanisms must include public awareness, whereby the public
need to be educated on the importance of preserving the water resources by properly disposing of
all the wastes may it be single household, municipal or untreated industrial wastes. Public being
the perfect majority, if they understand the need to keep water safe, then the pollution of water
and environmental degradation can be eluded. It is estimated that in the future, the adverse effects associated with water pollution and environmental degradation will be adverse such that
competition for the scarce unpolluted water sources will be unavoidable. To prevent this from
happening the relevant authorities should enforce the law for proper wastes disposal and management to all members of the public (Postel, 2000). People living in areas where water is scarce
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should be educated on how to utilize the little water they have and be encouraged to embrace recycling of the water by all means possible. Constructed wetland treatment systems for household, industrial and municipal wastewaters recycling help those people struggling with the scarcity of water to save money. People should be encouraged to embrace improved farming practices and sewerage management to help the problem of water scarcity from increasing any further.
Globally some organizations have taken a step in enhancing clean water initiatives in areas affected by water scarcity. Strategies for water conservation are backed up by advance water conservation technologies that are designed to help in conserving water. Although there are organizations and support groups that encourage the conservation of water, the public should also be
encouraged to protect water source from their perspective. Life on earth for all things can be
saved if necessary resources for water conservation are put to work. The strategy of conserving
water benefits the society and also helps the environment and water utilities altogether.
The concept of sustainability can be integrated into both human activities as well as the
general human society (Praewa, 2017). There would be adverse effects on the ecosystem which
is essential for sustenance and support of human life if the human activities were less sustaining.
Present-day approaches have been designed to incorporate sustainability, environmental ethics
and the participation of public efforts in creating developmental projects in the communities. For
those communities that are exhausting the scarce water sources they have, they are encouraged to
recycle the little they have an ideal approach to deal with the problem. Known and unknown water constituents that are added to the public water used in industries, households and for commercial purposes results to the water being household, municipal and industrial wastewaters. Construction of a continuous wetland for wasteland treatment is an approach for municipal, single
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household and industrial wastewaters, which enhances the basis for water reclamation and reuse
most essential water resources management programs in the whole world (Praewa, 2017).
Constructed wetlands (CW) are managed and engineered wetland systems that are gaining
worldwide popularity in wastewater reclamation and treatment. They are systems that naturally
performs pollutant removing process mediated by complex interactions between soil/gravel media, water, vegetation and their associated microbial assemblages and the environment to improve water quality in a viable way. Constructed wetlands are designed to exploit the physical,
chemical, and biological treatment processes that are found in wetlands and give a provision for
organic material reduction, nutrients, metals, total suspended solids, pathogenic organisms and
biological oxygen demand. Constructed wetlands are less costly and operation and maintenance
are easy and they have a great potential for application in households, industries, and municipals.
Limitations of Constructed Wetlands
Like any other new municipal, industrial and single household wastewater approach, the
Constructed Wetlands systems have limitations of their own that sabotage their effectiveness in
the landscape. In contrast with other wastewater conservation systems that accomplish the same
purpose, they tend to occupy large pieces of land. This limitation, therefore, makes this approach
to be only suitable in places with the availability of land with low prices and rates. Constructed
Wetland system is not a cost friendly approach because it has economic deficit making it impossible for people who do not have large pieces of land or the money power to buy one unable to
construct them. Therefore in some case Constructed Wetland system is a complicated task because it is expensive (Jhansi, & Mishra, 2013). Water treatment effectiveness is hindered by the
fact that biological components are in most cases sensitive to chemicals such that any water
surges will affect the process. Although the wetlands are designed in a way that can survive in
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very little amounts of water, they cannot survive completely in areas that are dry or in other
words they are not engineered to survive in areas of trying circumstances. Cold weather conditions do weaken the effectiveness of the wetland system and also high temperatures that may be
as a result of dry spells and drought, affect the performance of the system too. Additionally,
heavy rains also have an impact on the effectiveness of the constructed wetland systems most
especially during the spring season. The system effectiveness is dependent to the many changing
weather patterns and therefore their effectiveness in the treatment process for municipal, single
household and industrial and wastewaters are gradually compromised (Crawford, & Sandino,
2010).
The application of constructed wetland systems for municipal, industrial and single
household wastewaters is to some extent new concept, and for this reason, the technology which
purportedly can be used to reinforce its effectiveness is not fully developed. Some ecological and
environmental critiques believe that more should be done to realize full efficiency of the single
household, industrial and municipal constructed design system.
Problem Statement
Most developing countries have the challenge of industrial, municipal and single household wastewater management because they have limitations in getting wastewater management
technologies that are cheap and can be used in the application of generating the most effective
effluents in order to satisfy single household, industrial and municipal functions. The sole purpose of wastewater management is preventing the spread of diseases and infections that are
caused by water contamination. Additionally, nutrients recovery, water reuse, and reclamation,
including conserving water resources are other wastewater management objectives that most
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world organizations are working to attain. A change from conventional wastewater management
to more efficient and effective wastewater management should be embraced in the whole world
(Praewa, 2017).
According to (Praewa, 2017) once the change has been gained then there would be conservation of environmental resources and water, hence making it sure that the overall objective
of many wastewater treatment systems has been achieved. In this case, this report intends to create a full analysis and assessment of the constructed wetlands systems in facilitating the quality
and effectiveness of wastewaters and the related environmental hazards and threats that may crop
up as a result of wetlands. The discharges and effluents that emerge as a result of water pollution
should be disposed of in a way that they do not cause spread diseases and infections to the members of the society. There are many harmful effects of the water pollution to the surroundings and
to the general health of the public. Stagnant polluted water bodies give mosquitoes a good breeding site this puts people at a very high risk of contracting Malaria which is one of the most killer
diseases in the world especially infants and young children. Some wastewater systems have the
propensity of overflowing and clogging on surfaces (Praewa, 2017). Constructed wetlands, require a vast land to build compared to other conventional wastewater systems this sometimes
makes them very expensive.
Objectives
Design of Constructed Wetland for municipal and industrial applications:
This study discusses the design, performance, percentage removal and water balance of assorted
designs of the constructed wetlands treatment system for the use of treating wastewater.
1. Review of Constructed Wetland designs for single households – onsite wastewater treatment,
influent/effluent quality, different designs, reuse criteria, examples - case studies
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2. Review of Constructed Wetland designs for municipal wastewater – influent/effluent quality,
different designs, reuse criteria, examples – case studies
3. Review of Constructed Wetland designs for the oil and gas industry – influent/effluent quality,
designs, reuse criteria, examples - case studies
Literature Review
Domestic, Municipal and Industrial Wastewater
In this time and age, the issue of municipal, industrial and single household wastewater is
of great concern because it causes severe environmental problems to the environment and it also
affects people in terms of their health. Municipal, industrial and household wastewaters are environmental related issues whose negative impacts affect, all living organisms, whether it’s animals, human beings or the environment. Studies have approximated that wastewater is exactly
99% water while the remaining 1% is a mixture and combination of suspended, dissolved organic solids, detergents and also a mixture of chemicals (Secretariat, 2014). A single household,
municipal and industrial wastes are types of wastewaters.
Sewage” is one kind of wastewater, household wastes from toilets, kitchen sinks, and
showers are constituents of sewage and are disposed of via sewers. Municipal wastewaters commercial inputs range from photofinishing shops, restaurants, and car washes as well as bars recreational facilities (Secretariat, 2014). Frequently, pretreated industrial wastewaters constitute the
municipal wastewaters flow. A wide variety of process and facilities that consist of Plastic manufacturing wastes, pulp, petroleum refineries and food processing, results in the formation of industrial wastewaters.
According to Secretariat (2014), different types of wastewaters (single household, municipal and industrial) have varying chemical compositions, for instance, pathogens, bacteria, and
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nutrients. Wastewaters untreated components cab be organized in three categories which include
physical, biological and chemical components. Solid and inorganic constituents in the
wastewaters are what comprise the physical components. Biological components in wastewaters
are made up of bacteria, viruses, protozoa and other pathogens in the wastewaters. Lastly, chemical components are made up of dissolved and organic matters as well as nutrients and metals
which in most cases are heavy metals.
In rare cases, industrial, municipal and single household wastewaters might contain reusable resources, for example, carbon, water, and other nutrients which could be recovered or reused in other cases. For effective effluent regulatory standards to be met and be satisfactory then,
the wastewater will need to be treated in order to get rid of all water pollutants which might be
found in the municipal, industrial and single household wastewaters and should undergo appropriate treatment (Crawford, & Sandino, 2010). According to Crawford & Sandino (2010), the
wastewater treatment process should be focused on the recovery of resources so as to be selfsustaining.
Water engineers and scientists have been on the edge trying to figure out the most appropriate technologies which would be embraced to ensure the effectiveness and efficiency of
treatment systems are achieved and all this has been attributed to the critical issues which are exhibited in the wastewaters. The most known and basic systems of single household, municipal
and industrial wastewaters treatment are integrated into the reduction of organic water compounds and the suspension of solids so as to attain the needed effluent regulatory standards. With
noticeable progression in the advancement of new technologies by water engineers and environmental scientists, a wastewater treatment approach has been developed in order to help in the absorption and removal of dissolved toxic substances and organic matter from the wastewaters.
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Advancement in the scientific knowledge and consciousness about the environment and
water bodies have given rise to new and improved technologies and treatment systems as well
which are quite helpful in curbing pollution in wastewaters and also reduce the energy used in
the recycling of the industrial, single household and municipal wastewaters. Therefore, while
selecting the appropriate technology to help in solving the wastewater problem, great care and
caution should be considered. Generally, there are two types of wastewater treatment systems
and they are the conventional wastewater treatment and the sustainably constructed wetlands
treatment system.
Conventional Wastewater Treatment
Conventional Wastewater Treatment Process
Conventional wastewater treatment process is made up of physical, chemical and biological processes. This treatment process encompasses three stages which are referred to as the primary, secondary and tertiary treatment.
Primary Treatment
This treatment is used in the removal and the separation of inorganic materials as well as
solids which would otherwise clog and destroy water pipes. This type of treatment entails screening, grit removal, and sedimentation. Screens in this treatment are used to get rid of large debris
which includes plastic and cans. Grit chamber system is used to remove and settle sand and
gravel. According to Nelson et al (2007), the wastewater is moved into the quiescent basin, with
a temporary retention, and then eventually heavy solids settle at the bottom of the basin while
lighter solids, grease as well as oil move to the upper surface of the quiescent basin. Finally,
skimming and sedimentation processes are used to both the settled and floating pollutants in the
wastewaters then the liquid which remains is transferred and discharged so as to pass through the
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secondary treatment. 50% of the total suspended solids, 30%- 40% of BOD are gotten rid of in
this stage (Nelson et al, 2007).
Secondary Treatment
Dissolved and biological matters are removed by use of secondary treatment. According
to Nelson et al (2007), 90% of organic matter in the wastewater is removed through biological
treatment process at this stage. Attached growth processes and suspended growth process are the
best two suitable conventional methods used in the secondary treatment.
Normally in the attached growth processes, the algae, bacteria and other microorganisms
grow on the surface and as a result, biomass is formed. Trickling filters, bio towers, and rotating
biological contactors are all inclusive in the attached growth process unit. There is a suspension
in microbial growth in an aerated water mixture in the suspended water processes. However, activated sludge is the most common type of suspended water processes. The activated sludge process typically grows a biomass of aerobic bacteria and other microorganisms that are essential in
the organic waste breakdown.
Tertiary Treatment
Tertiary treatment is a more advanced form of the treatment. Compared to primary and
secondary treatment, tertiary treatment is used in the production of high and quality effluent and
discharge in a bid to discharge in the too fragile ecosystem like estuaries and low-flow rivers.
Tertiary treatment is purposefully used in the provision of the last and final treatment stage so as
to achieve the targeted and desired levels of the raised effluent quality. Coagulation sedimentation, filtration, reverse osmosis, and extending secondary biological treatment are some of the
methods that can be achieved through the advanced tertiary treatment. These methods are further
used to remove nutrients and stabilize oxygen in more oxygen-demanding substances. Treated
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effluent can then be safely reused and recycled because of the higher and advanced degrees purification of wastewaters (Praewa, 2017).
Under most familiar circumstances, disinfection process is needed before treated
wastewater is discharged. Once disinfectants are added to the water systems, then the pathogens
and microorganisms found in the water are killed. The treatment of wastewaters makes use of
disinfection in order to minimize the number of microorganisms and pathogens in the water before the water can be discharged back into the environment and regardless of the water treatment
used, this is normally the final treatment process. Chlorine and ultraviolet lights are amongst the
most known and common methods used in the disinfection of water. The treated water can then
either be discharged into different water bodies or be used in agricultural irrigation (Praewa,
2017). The treated water can be used for agricultural use or underground water recharge should
the water meet the required set standards.
Constructed Wetlands
Constructed wetlands (CWs) design systems for single household, municipal and oil and
gas are a type of wastewater treatment system which is designed and structured in ways that imitate the natural process of wetlands. Unlike another treatment process that occurs in nature in
wetlands, this system has advantageous aspects. Constructed wetlands for a single household,
municipal and oil and gas incorporate chemical, biological and physical processes that are used
in the enhancement and improvement of the quality of water and the removal of pollutants in the
water (Vymazal, & Kröpfelová, 2008). These design systems which have macrophyte aquatic
microbial communities and plant roots and supporting mineral matter are of great benefit and
effective in the pollutants from wastewaters and these pollutants include, nitrogen, metals, pathogenic organisms among many others.
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In 1904, the first ever constructed wetland was built in Australia. The technology advancement within the field of constructed wetlands is still under-developed in spite of the fact
that the constructed wetlands have been in existence for over a century (Vymazal, & Kröpfelová,
2008). As the increase of constructed wetlands continues across the world, it is continuing to find
favor among many ecologists, scientists and even water and environmental engineers because of
its many benefits as compared to the traditional treatment processes. Many people prefer constructed wetlands over the other conventional treatment systems because of the benefits and effectiveness of the system and due to these reasons; it is getting popularized even among developing countries globally.
Advantages of Constructed Wetlands
Constructed Wetlands design systems for industrial, municipal and single household
wastes, are not only a cost-friendly but they are also effective in the treatment of wastewater and
runoffs. Constructed wetlands for municipal, industrial and single household wastewaters are
helpful in the facilitation of water reuse and reclamation in many regions globally (Postel, 2000).
They also act as habitat for the many wetlands’ organisms. In addition, Constructed Wetlands is
an environmental-sensitive approach that has been admired and accepted by the members of the
public since they are designed in a way that fits perfectly in the environmental landscape.
Structured and managed water systems like the constructed wetlands (CW), is a system
that is receiving major global attention because of its effectiveness in industrial, household and
municipal wastewater reclamation and reuse. By embracing Constructed Wetland systems, the
quality of water, microbiological assemblages, and the environment is gradually improved.
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Through this system, storm water runoffs, domestic wastewater, and industrial wastewater is
used to best help in the treatment of petroleum refinery wastes, pretreated industrial wastewater,
and fish pond wastewater; and once the wastewaters are treated then their adversity on the public
water system and the environment is reduced (Vymazal, & Kröpfelová, 2008). Constructed Wetlands in most cases are structured in a way that determines the physical, biological and chemical
water treatment processes that naturally occur in the wetlands, are responsible for organic materials reduction and are also responsible for the provision of the high biological oxygen demands.
The Main Benefits and Outcomes of the Constructed Wetlands
The constructed wetland is a beneficial wastewater system for the municipal, industrial
and single household because, upon treatment, the water that is discharged can either be used for
domestic activities or can be directly discharged to the environment. It is also beneficial to the
end-users as the construction cost is minimal, the cost of operation and the maintenance cost is
affordable. The maintenance and the operation of the constructed wetlands are periodic, unlike
other conventional water treatment system which in most cases require continuous, on-site labor
(Crawford &.Sandino, 2010) The constructed wetland design system for municipal, industrial as
well as single household, facilitates the recycling and reuses of water and saves the cost. The
constructed system not only provides a habitat for the wetland organisms but it is engineered in a
way that it finds favor in the eyes of mankind because of its many benefits.
Types of Constructed Wetlands
They are various types of constructed wetland design systems for municipal, industrial
and single household wastewaters depending on the landscape. The types include; surface flow
(SF) and subsurface flow (SSF). SF constructed wetlands have shallow flow and have a lower
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velocity above with substrates. The SSF wetlands flow either vertically or horizontally in the
substrates. Therefore SSF constructed wetlands can be further categorized into horizontal and
vertical flows. Hybrid constructed wetlands is a combination of both the vertical and horizontal
flows (Vymazal, & Kröpfelová, 2008). Each type of the constructed wetland design system for
an industrial, municipal and single household has its own benefits and downsides as well. These
types of constructed wetlands differ in the treatment process. The SF-CWs makes use of plant
stems as well as leaves and rhizomes in order to effectively treat the water effluents. In dense
vegetation, however, the process can be limited because there would be no enough circulation of
oxygen which is vital for organic animals and organisms. In the SSF-CWs, the roots are used in
the treatment of effluents as water passes through a series of gravel beds. This process is considered superior and effective to SF-CWs.
Components of Constructed Wetlands
Water
Places where landforms in most cases direct surface water straight into shallow basins, as
well as other places where impermeable subsurface layers hinder the ground from absorbing surface water, are the most likely places where wetlands can form. Such conditions in a place can be
designed to engineer the creation of wetlands (Jhansi, & Mishra, 2013). A land can be structured
in the way that collects surface water and seals all the basins in order to retain the surface water
collected and once all these modifications have been done to a landscape then a wetland can be
properly structured of constructed.
In the construction of wetlands systems for industrial, municipal and single household
wastewaters, hydrology is among the most important factors that should be put into consideration. This is because it not only links all wetland functions but it also is a key factor in the failure
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or the success of a given constructed wetland on a landscape. The hydrology of constructed wetlands is important when compared to the hydrology of other surface...