J Appl Biotechnol Bioeng. DOI: Download PDF. Pollution of industrial waste water caused by the discharge of harmful chemicals and substances into water, making it unsuitable for consumption and for other purposes. Since the industrial revolution, we have achieved many things; our manufacturing process to become more efficient and productive, science has become more sophisticated and our lives have changed.
But perhaps nothing comes without a price. All the progress and development seen in past centuries have also brought with them a wide range of problems; water pollution is one of them. Fouling refers to pollution and hazardous waste environmental materials, which lead to a significant change in the quality of the surrounding atmosphere.
Pollution of the environment can be classified as air pollution, water pollution and noise. Water pollution means water pollution, which is unfit for consumption and for other purposes. There are essentially five main sources of water pollution from domestic wastewater, agricultural run-off and industrial wastewater, sewage from septic tanks and rainwater.
There is a lack of stringent pollution control policies in many countries around the world, particularly in developing and underdeveloped countries. In many countries, policies exist, but the apathy of law enforcement authorities has allowed industries to take these laws for granted and easily circumvent them. Some industries still rely on old and obsolete technologies that produce more pollutants than modern technologies. Industries essentially try to avoid the high cost of modern or sophisticated technologies by using outdated technologies, although they are known to be less efficient than modern technologies.
In many countries, industrial water is not treated adequately before it is discharged into rivers or lakes. This is especially true for small industries that do not have enough capital to invest in pollution control equipment. Unplanned industrial growth contributes to water pollution. Although industrial growth stimulates a country's economy, it degrades the environment, especially when it is unforeseen.
Growth can also contribute to limiting waste disposal sites and total disregard for pollution control laws are negative consequences of unplanned industrial growth. The extraction of minerals by mining and drilling causes pollution of industrial water. Extraction and drilling operations render the land unusable for agricultural activities and any accidental leakage can escape into the surrounding water and enter the ocean.
Oil spills can pollute land and sea. Waste generated during mining operations can increase the salt and mineral content of water and change its pH. Mine mining pollutes both surface water and groundwater. These wastes generated in various industrial processes can basically achieve these changes, when poured into water bodies.
Industrial water pollution can have far-reaching consequences for the ecosystem. Water is used in various industrial processes, coming into contact with toxic substances, heavy metals, organic sludge and even radioactive sludge. The world is faced with the dilemma of achieving balance between economic development and sustainable natural environment. Effective wastewater treatment has been earlier identified a way of protecting the water environment with detailed discussion on effective, cheap, and accessible method of wastewater treatment [ 27 ].
Various environmental policies stipulating discharge protocols exists. These policies are however not effectively executed as the industries consider them as damaging to business. The ability of industries to run with the various environmental discharge policies will sustain our natural environment.
Policy integration, that is, factoring environmental issues of concern into the core of economic development, is highly important to facilitate policy performance. The main actors in environmental issues, that is, the industries, agro firms, and populace, show very little understanding of the impact of their activities on the present and future environment.
While organized periodical training concerning environmental sustainability should form part of environmental policy objectives, ensuring that these objectives are integrated into sectors plains and policies is important. Drinking water supplied to our communities is usually sourced from rivers, springs, and underground sources. Usually, some form of treatment is carried out to ensure the water is fit for drinking although some sources are somewhat free from contaminating microorganism and can be clean, for example deep well.
In many developing countries, one source of water can serve many uses such as drinking, washing, swimming, bathing, etc. In the same vein, sewage can be channeled into water bodies. Sewage can be defined as used water draining out of homes and industries that contain a wide range of debris, chemicals, and microorganisms.
Such water is regarded as potential health hazard to consumers or the users of other sort. A major kind of hazard is the presence of pathogenic organisms in such water. This is why water is usually treated in three phases [ 43 , 44 ]. The first is to separate large matter in the water source and the second stage focuses on removing more toxic substances and other matter. The tertiary phase involves total purification of water commonly by chemical disinfection.
More recently, membrane bioreactors are being used and have been found to be very efficient in removing contaminants. These are combinations of communities and high-efficiency membranes that are much more effective at removing contaminants. The role of microbes is obvious in the second stage where microorganisms actively carry out biodegradation of organic matter in the aqueous portion produced after the first stage.
Biodegradation of materials, such as paper and petroleum, are by bacteria, algae, and protozoa. When water is exposed to air, soil as well as effluents, it gains saprobic microorganisms; it can also pick up pathogens such as Cryptosporidium , Campylobacter , Salmonella , Shigella , etc.
To monitor water for each of these pathogens may not be possible but detection of fecal contamination is an easier way of spotting contamination. In such case, when the fecal contamination is high, pathogens are believed to be present and the water is unsafe for drinking.
Hence, indicator organisms are used as tools to detect fecal contamination of water. They usually inhabit the intestine of mammals and birds and can be easily identified using common laboratory procedures. To achieve water protection, it will be almost impossible to search for the pathogens themselves. An indicator bacterium should be applicable for analysis of all types of water; it should be found anytime enteric pathogens are present and it should thrive in the wastewater longer than the toughest enteric pathogen.
In addition, such organism should not reproduce in the contaminated water because this will give exaggerated values and it should not be harmful to human begins.
Other criteria are that the level of contamination should be directly proportional to the level of fecal contamination; assay procedure for the indicator organism should be highly specific and the test procedure should be easily performed. Coliforms are members of the family Enterobacteriaceae they include E.
Microbial contamination of water can be detected by checking for certain organisms including heterotrophic bacteria, coliforms, and Escherichia coli in such samples. The work by Kora et al. They also reported that contamination by E. Control of pathogens in water is important to prevent waterborne diseases; this can be effectively done using multiple barrier approach. Microbial treatment methods goes further than traditional municipal wastewater treatment, because it takes into consideration the removal of nutrients e.
A more advanced design is required in the bioreactor to be used. Some parameters to be considered in designing a treatment system are biomass yield, nutrient addition, the supply of oxygen or other electron donor, pH control as well as kinetics, that is, biological reaction rates biotransformation.
It is important to note at high concentration many compounds of interest are toxic to bacteria being used for treatment. Also some dissolved organic and inorganic compounds may constitute inhibitors to biodegradation by the organism.
Biological treatment processes may not consist of the following—lagoon treatment, activated sludge as well as fixed film bioreactors. The lagoon treatment is long-detention time basins; but unlike activated sludge processes, they do not use solid recycle. Such treatment scheme may be in three categories: anaerobic lagoon treatment, which makes use of highly loaded lakes creating anaerobic conditions. It has been used successfully for the pretreatment of meat and poultry processing wastewater reducing the biochemical oxygen demand considerably [ 47 ].
In the case of facultative ponds, there is an aerobic surface and an anaerobic bottom. The top aerobic layer facilitates treatment of dissolved organic compounds as well as odourous compounds. This has found application in pulp and paper industries. With regards to aerated lagoons, oxygen is provided by mechanical means or diffused aeration and the solids are continuously mixed and in suspension. Another biological treatment process of interest is the activated sludge.
It is made up of an aeration basin where aeration equipment provides both oxygen and adequate mixing of wastewater to maintain a uniformly mixed liquor suspended solids MLSS.
The aeration basin is followed by a liquid—solid separation usually in a clarifier by gravity and finally the settled biomass is returned again to the activated sludge basin. Examples of aeration basin configurations are — plug-flow systems, single completely mixed basins, and basins in series. The solid retention time SRT is important in this treatment process. The solid retention time is the average time biomass is maintained in a biological treatment process reaction.
The clarifier is very important in the performance of activated sludge processes. It ensures that efficient clarification and thickening of mixed liquor occurs.
When the readily degradable soluble biochemical oxygen demand is high in wastewaters, growth of filamentous bacteria is encouraged leading to poor sludge settlement. The use of powdered activated carbon PAC has been discovered to enhance the efficiency of activated sludge processes. The PAC functions by adsorbing inhibitory chemicals or adsorbing chemicals that buffer variable loads. Apart from the aforementioned, anaerobic bioreactors are also beneficial for the industrial wastewater treatment.
This is because it is cost effective and can be used for industrial wastewater with high strength. The processes in the anaerobic bioreactor lead to the production of mainly methane as well as other gases. However, there is a need to strike a balance between fermentation bacterial activity and methanogenic bacteria activity as the latter is slow growing.
Advantages of anaerobic treatment include low sludge formation, production of useful product, low nutrient requirement, and more importantly less energy requirements since aeration is not necessary. In addition to the energy production, advantages of anaerobic wastewater treatment, high organic matter removal efficiency, low excess sludge production, and stable operation are characteristics of this wastewater treatment technique [ 51 ]. A most recent advancement in the biological treatment of wastewater is the use of membranes in bioreactors.
In such cases, the membrane can serve three major purposes. Firstly, membranes can be used as a surface for the attachment for growth of organisms and to permit oxygen to permeate into the biofilm. An example of this is the hollow-fiber gas-permeable membranes in wastewater treatment. The second way membranes can be used as selective barriers.
Such membranes permit organic compounds in wastewater to permeate but do not transport ions into the bioreactor.
Thus, it allows for the selection of biodegradable organic compounds. An example of a material used for such membrane is silicone rubber. Finally, membranes can be for biomass separation. This third category requires that the membrane be used instead of a clarifier after activated sludge treatment. When such membranes are used, the effluent produced is of high quality and less sludge. In addition, automated processing can be easily employed.
The disadvantage however is the financial enormity of the investment for initial start-up as well as maintenance [ 50 , 52 , 53 ]. Since coliform bacteria are often detected in drinking water and often, the source of contamination is not known, it is important to put in place control measures. The water distribution systems must be considered because water quality deterioration i.
This can be as a result of reduced maintenance of the distribution system or from insufficient treatment and may lead to undue microbial growth, which the consumer may not notice. Water distribution systems should be periodically flushed to remove sediments, deposits as well as the growth of microorganisms within the pipe. For areas where the flow rate is low and possibly of the water becoming stale is high, a secondary disinfection using monochloramine and proper maintenance should be carried out in such as to prevent nitrification.
Another point is to avoid a break in the distribution system especially during construction, repairs or installations, and cross connections. The officers should also ensure that the level of treatment a water sample is given is in conformity with the quality of the source of water.
Also, the sampling for laboratory analysis must also be taken into consideration and monitored thoroughly when aseptic techniques are compromised, detection of coliforms may occur. Even though reports of water diseases have been low and less serious in most developed countries, it is still a major concern in some underdeveloped countries especially war-ravaged countries.
It is however important to operate a multibarrier approach, which will ensure protection of the water source, and also certify adequate treatment and distribution of water. It is however important that every occurrence of coliforms in drinking water be properly investigated so that if the contamination is as a result of operational deficiency, this can be addressed and future occurrence is prevented, thus safe guarding the health of the public [ 54 ].
Several modern methods of water purification have been well embraced in our society today. However, some rural dwellers who may not be able to afford these modern treatment methods still have water pollution as a major challenge [ 55 ]. Furthermore, the disinfection by-products which remain after treatment is another reason why herbal attempts in water treatment should be encouraged.
It is important to note that not many researchers apply their antimicrobial extract or fractions directly in water treatment. Many groups stop at establishing the antimicrobial potential of their study plant, whereas others go further to apply the extracts in water treatment. For instance, a reported work used alcoholic, aqueous, and fresh juice extracts of Ocimum sanctum tulsi and Azadirachta indica neem and applied them in vitro against salmonella, which was chosen as an indicator organism.
Elevated temperature typically decreases the level of dissolved oxygen DO in water. The decrease in levels of DO can harm aquatic animals such as fish, amphibians and copepods. Thermal pollution may also increase the metabolic rate of aquatic animals, as enzyme activity, resulting in these organisms consuming more food in a shorter time than if their environment were not changed.
An increased metabolic rate may result in food source shortages, causing a sharp decrease in a population. Changes in the environment may also result in a migration of organisms to another, more suitable environment, and to in-migration of fishes that normally only live in warmer waters elsewhere. This leads to competition for fewer resources; the more adapted organisms moving in may have an advantage over organisms that are not used to the warmer temperature.
As a result one has the problem of compromising food chains of the old and new environments. Biodiversity can be decreased as a result. It is known that temperature changes of even one to two degrees Celsius can cause significant changes in organism metabolism and other adverse cellular biology effects.
Principal adverse changes can include rendering cell walls less permeable to necessary osmosis, coagulation of cell proteins, and alteration of enzyme metabolism. These cellular level effects can adversely affect mortality rates and reproduction.
Primary producers are affected by warm water because higher water temperature increases plant growth rates, resulting in a shorter lifespan and species overpopulation. This can cause an algae bloom which reduces the oxygen levels in the water. The higher plant density leads to an increased plant respiration rate because the reduced light intensity decreases photosynthesis.
This is similar to the eutrophication that occurs when watercourses are polluted with leached agricultural inorganic fertilizers. A large increase in temperature can lead to the denaturing of life-supporting enzymes by breaking down Hydrogen bond and disulphide bonds within the quaternary structure of the enzymes. Decreased enzyme activity in aquatic organisms can cause problems such as the inability to break down lipids, which leads to malnutrition.
In , the Chicago Tribune accessed industry reports through the Freedom of Information Act, and discovered that numerous older power plants have been exempted from environmental regulations designed to prevent enormous industrial fish kills.
These older plants, employing "once-through" cooling, pump massive amounts of water from lakes and rivers through the screens of water intake systems - some so powerful they could fill an Olympic swimming pool in less than a minute - and sucking up multiple fish. Dozens of older power plants that ring the Great Lakes kill hundreds of millions of fish each year as a consequence of employing outdated processes to cool their equipment.
Not far away, at the mouth of another important Lake Erie tributary, the Monroe Power Plant in Michigan kills more than 25 million fish and almost a half-billion fish eggs and other organisms each year. FirstEnergy's Bay Shore power plant also withdraws more than million gallons of water per day from Lake Erie, using vast quantities of "once-through" water used to cool equipment exits, and creating prime growing conditions for bacteria that harm native fish habitat.
Some facilities use once-through cooling OTC systems which do not reduce temperature as effectively as the above systems. Section b of the Clean Water Act CWA requires the EPA to ensure that the location, design, construction, and capacity of cooling water intake structures reflect the best technology available BTA for minimizing adverse environmental impacts, including thermal pollution.
The EPA has been in the process of developing a rule that will define how States will establish standards for cooling water intake structures at large power plants, expected to be published in the Federal Register in September The rule would apply to large existing power plants that withdraw 50 million gallons per day or more, and that use at least 25 percent of their withdrawn water for cooling purposes only - an estimated fossil-fueled and 38 nuclear power plants representing over and 52 GW of existing capacity, respectively.
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