Introduction
Over the years, industrialization has become an important aspect in the development of any nation economy and has become an important parameter to look out for when it comes to measuring the nation’s status in the international community. However, research has shown that the operations generated unwanted by-products (waste) which has notably contributed immensely to the pollution of the environment (Air, Water and Land).
Waste can be defined as any substance or material that is abandoned, overused, underused and carelessly used and when recycled, it generates fund to the society or to an individual (Gupta and Mahanjan, 2005). The European Centre for waste defined waste as all items that people no longer have any need for, which is either intended to get rid of or had already been discarded. Generally, waste can be derived from several sources ranging from domestic, commercial and or industrial. Industrial wastes have also been defined as waste produced by industrial activities, which include any material that is rendered useless during a manufacturing process such as that from factories like rubber factories, mills and mines, etc (The Free Encyclopaedia). Industrial has always existed from the onset of the industrial revolution; It can be generated from industries such as refineries, rubber and plastic factories, textile plants etc. These wastes can cause great concern to public health due to obnoxious odour, pollution of land, water and air (Oreyomi, 2007). Waste from Industrial activities can either be hazardous or non hazardous depending on the source, nature and toxicity and may exist in solid, liquid or gaseous state (Adeniji and Karibo, 2008). Olojoba (2009) defined hazardous waste as any waste which because of its physical or chemical quality may cause illness or significantly contribute to the destruction of life.
The process of industrial waste management on the other hand involves the collection, transportation, treatment and or disposal of unwanted materials produced by industrial activities in such a manner that it will not cause harm to the public, protect the environment and promotes aesthetics of the environment (Olojoba, 2009). Significantly, there has been environmental policy guiding the generation of waste from industrial operations and their disposal from industrial operations into the environment, but sadly most industries still dispose their waste into the adjoining surrounding/environment without any treatment or consideration of public health. This shows that the strategies in place for the implementation of these policies are weak or ineffective in most states, thus the challenges of industrial waste management (Olojoba, 2009).
In light of the above, there is therefore the need to assess the industrial waste management processes of industrial effluent (liquid waste) shall be focused on as one of such waste produced by industrial activities so as to assess its impact in the environment and health of the public to the benefits humanity and the environment.
Conceptual framework
The human environment is composed of land, water and air. Man’s activities within his environments such as industrialization and economic development have brought about tremendous changes with their attendant consequences. One of these consequences is enormous waste generation since human environment and waste generation are two twin sisters. One cannot be separated from the other. These wastes include solid waste, sewage (effluent), industrial waste etc.
Effective management of industrial waste without causing harm to human health as well as enhancement of aesthetic value of the environment has been a problem over the year. Reason for these are not far-fetched, and so to get the basic understanding of this study, there is need to review and study of propriety books, journals and articles which deals with the subject matter.
Industrial effluent (waste)
Oreyomi (2007) defines industrial waste as those useless, unwanted and discarded waste materials resulting from industrial processes. WAHEB (1991) classifies industrial waste to either be solid, liquid and or gaseous contaminants. According to Adeniji and Karibo, (2008), industrial wastes are either hazardous or non-hazardous depending on the source, nature and toxicity. In Nigeria, it has been observed that almost every industry dumps their waste on the backyard without concern for the neighborhood or the environment. Most industrial waste especially effluent are disposed off in open undeveloped lands, stored in surface impoundment as lagoon, pits, surface water etc with either little or no treatment process. Industries tend to generate a large amount of waste water and this is highly polluted. Their disposal options include discharge into public sewer or a watercourse. This has led to high level of water, land and air pollution as well as damages wildlife and vegetation. Studies have shown that high levels of toxic contaminants have been found in animals and human who have been continually exposed to the source of industrial effluent disposal site.
Sources of industrial effluent
Olojoba (2009) stated that the manufacturing industries have been identified to account for a quarter percentage of industrial waste. Also mining agriculture and commercial activities generates waste. However, sources of industrial waste can be classified into hazardous and non-hazardous waste.
Hazardous waste
Hazardous waste is anything which because of its physical or chemical quality many cause illness or significantly contributes to destruction of life. Consequently, an industrial effluent is said to be hazardous if a possess any of the following characteristics; corrosive, toxicity, reactivity and flammability and this may include acids, toxic chemical, explosives and other harmful or potentially harmful substances (Olojoba, 2009).
Non-hazardous industrial waste
According to Olojoba (2009), non-hazardous wastes are those wastes that cannot easily pose threat to human health and the environment. This could be from food and beverages industries where effluent are biodegradable and non-toxic but have high concentration of BOD (Bio-chemical oxygen demand) complex organic chemicals industry including many different industries which contaminate water with pesticides, plants, detergents, etc.
Effect of industrial effluent disposal
The effects of industrial effluent disposal are dimensional on the three different environmental media. However, according to Adeniji and Karibo (2008), hazardous waste from industrial activities accounts for over 70% effects to human and environment. These effects include:
Land pollution
The increasing industrialization has lead to the pollution of soil through the discharge of effluents by the industrial units. Waste water discharged into the land and the subsequent washing down of the pollutants to successive horizons. These effluents discharged into the land by industrial units contain many toxic chemicals, mineral acids, bases, etc. Which over the period of time get deposited into the soil due to their retention or their absorption in the soil particles. This may encourage growth of fungal and bacterial colony in the soil. Also some of the deposited chemicals may be taken up by the plants/crops growing in such contaminated soil.
Water pollution
When toxic substances enter lakes, streams, rivers, oceans and other water bodies, they get dissolved or suspended in water whereby the quality of the water deteriorates affecting aquatic ecosystem. Pollutants can also seep down and affect the ground water deposits. The most polluting of water sources are the city, sewage and industrial waste discharge into the rivers. Presently, only above 10% of waste water generated is treated. The rest are discharged into the water bodies.
Air pollution
The smoke generated from industrial activities through machines and equipments pollute the air making it unsafe for humans. The important gaseous emulsions from Nigerian industries are Sulphur (iv) Oxide (SO2), Carbon Monoxide (CO) and Oxides of Nitrogen which tends to contaminate the atmosphere by reaching with it and producing acid rains. The evaporation of industrial effluents back into the atmosphere completing the hydrological cycle can also lead to contamination and eventually rainfall.
All the above environmental hazard of industrial effluent to human health, animal lives, plant lives and the economy shows that proper waste management and control is ultimately needed with the on-going global concern for sustainable development (Olojoba, 2009).
Industrial effluent disposal method
Effective industrial effluent management is a process of removing all contaminants from runoff (effluent) to make sure it is rendered harmless. Its objectives is to produce an environmentally safe fluid waste stream (or treated effluent) suitable for disposal or reuse.
Public sewers are convenient for disposal of waste water. If they are nearby quantity, strength and character of waste needed to be considered and authorities consulted for discharged to sewers. If approval is granted and the waste water meets the criteria set then sewer disposal would be an obvious choice (i.e. after treatment), but this cost at a cost. High COD (Chemical Oxygen Demand) and suspended solids would lead to high costs and reducing these parameters can make significant savings. Therefore partial or full onsite treatment would bring about cost saving, but need to be justified.
It is mostly advisable to carry out an evaluation of the process involved in industrial effluent management to identify sources of waste water. A proper audit would help to reduce waste and disposal costs and quantity flow rate, organic loads and characterized the waste water to optimize the design of any onsite treatment plant.
On the light of the above, to be able to control the hazardous waste generally, an industrial waste in particular, the best techniques according to African Development Bank (2002), is the application of 4RTD (Reduce, Reuse, Recycle, Recovery, Treatment and Disposal).
Reduce
This is the reduction of waste at source, meaning less waste generation through the use of more efficient practice. For example, equipment or technology modification process or procedure modification, redesign of products, substitution/elimination of materials, improvement in housekeeping, maintenance, training, inventory control, etc., can greatly help to reduce waste at source. This is the best preferred management method. (Adeniji and Karibo 2008).
Reuse
This is the use of materials or products in their original form or a different purpose. For example reuse of chemical containers, cleansing of drill cutting for road bed materials. It is the second preferred management option for waste. (EPA, 2001).
Recycling
According to Gupta and Mahajan (2005), this is the conversion of waste into useable materials after some forms of processing. e.g. recycled sewage water recycled as drinking water. This turns waste materials from waste to wealth.
Recovery
This is the recovery of materials or extraction of energy from waste. Example of this practice includes burning of waste oil for energy recovery, recovery of oil from tank bottom etc. (Aniefiok, 2004).
Treatment
Even after adequate minimization, there will be some waste requiring treatment before final disposal. The treatment option depends greatly on the waste characteristics and regulatory requirements. Available methods are usually limited by ecological, technical or economic factors. Waste treatment is aimed at reducing waste toxicity of the disposed.
Disposal
This is the last preferred option of the management of industrial waste. This option involves eventual disposal of waste after all other options have been explored. In contending with this option however, an engineered land fill is usually required for this option (Olojoba, 2009).
The role of the government in industrial effluent disposal
WAHEB (1991) states, “The environment is a life supporting system”. The government has a role to play in the protection of the environment by making laws and regulations, which controls humans and industrial operation, so as to achieve a sustainable development.
The following are put in place or put into consideration for efficient management of industrial effluent disposal;
Environmental agencies
These are regulatory bodies which the government uses in the formulation, implementation, reputation and enforcement of laws guiding the generation and disposal of industrial wastes. These agencies include:
- FME: Federal Ministry of Environment
- FEPA: Federal Environmental Protection Agency (now NESREA)
- State Ministry of Environment
Environmental legislations / standards / compliance
Environmental legislations are laws made to guide individual and industrial interactions with the environment so as to avoid the pollution of the environment (Unuraye, 2009). The petroleum Act of 1969 in Nigeria generally empowers these to the full to ensure full compliance with these laws as provided by the Petroleum Act (1969) the Department of Petroleum Resources (DPR) was instituted by Decree No. 33 of April 1 1977 to monitor the operations of the Exploration and Production companies. The tool used by DPR to ensure compliance is the “ENVIRONMENTAL GUIDELINES AND STANDARDS FOR THE OIL INDUSTRIES IN NIGERIA” published in 1992. However, there was another body, the Federal Environmental Protection Agency (FEPA) enabled by Decree No. 58 of 1988. FEPA was used to legislate for industrial operations in Nigeria as a whole. Presently, however FEPA has been scraped and in its place the National Environmental Standards/Regulation Enforcement Agency (NESREA) was instituted in 2000. However most of the policies, goals, strategies for implementation etc are still in place. To enable their performance, the federal ministries of environment and DPR have instruments in place which companies are required to comply with. These instruments are referred to as STANDARDS AND REGULATIONS.
Strategies for implementation
The implementation of the environmental legislature / standards depends on specific actions directed towards major sectors and problem areas of the environment. The actions includes legal, institutional regulatory, research, monitoring, evaluation and other relevant mechanisms for ensuring the attainment of the specific goals and targets of environmental policy. To this end, such tools as the Environmental Impact Assessment (EIA) enabled by decree No. 86 of 1992 was instituted to carry out prior environmental assessment of proposed activities which may affect the environment or the use of a natural resources. Hence procedural guidelines on how to carry out EIA on all new major projects in order to achieve sustainable development have been laid down. In most cases, the following technical activities characterizes the procedure; project proposal, Initial Environmental Examination (IEE), Screening, Scooping, EIA study, review, decision-making, mitigation compliance, monitoring and audition. (Environmental Affairs, 1999).
Some environmental and effluent (waste water) regulations in nigeria
These include;
- Factory Act, Cap 126 LFN 1990.
- National Environmental Standards and Regulation Enforcement Agency (NESREA) Act (LFN, 2004).
- Harmful Waste Act, Cap 165 LFN 1990
- Water Resources Act.
- River Basin Development Authority Act.
- Criminal Code Act (LFN, 1990), etc.
Instruments of intervention
The following according to the constitution of the Federal Republic of Nigeria (1999) as amended and NESREA ACT 2007
- Section 20 of the Nigerian Constitution (1999) makes it an objective of the Nigerian State to improve and protect the air, land, water, forest and wildlife of Nigeria.
- Section 33 and 34 which guarantee fundamental human rights to life and human dignity respectively, has also being argued to be linked to the need for a healthy and safe environment to give these rights effects.
- Section 7 of the NESREA ACT 2007, provides authority to ensure compliance with environmental sanitation and pollution with environmental sanitation and pollution prevention and control through monitoring and regulatory measures.
- Section 8 (1) (K) empowers the agency to make and review regulations on air and water quality, effluent limitation, control of harmful substances and other forms of environmental pollution and sanitation.
- National Effluent Limitation Regulation 5.1.8 of 1991. This make it mandatory for industrial facilities to install anti-pollution equipment, makes provision for effluent and prescribes maximum limits of effluent parameters allowed for concentration.
Challenges of industrial effluent disposal
Efficient industrial effluent management and disposal is a challenging issue in most Nigerian industries. Major challenges of effective effluent disposal can be attributed to the under mentioned factors according to Adeniji and Karibo (2008), Olojoba (2009) and Oreyomi (2007).
Lack/shortage of trained personnel
According to Oreyomi (2007), there is no gainsaying that requirement for trained personnel for effective industrial waste management is a major challenge of industrial waste management in the Nigerian industries. On many occasions, old men who are unskilled, form the bulk of the employees in the industries. These men are grossly underpaid. This no doubt, led to inefficiency in the management of industrial wastes.
Lack of equipment
Second to lack of trained personnel in industrial waste management system is the lack of equipment. The process of waste management system involves collection, transportation, treatment and disposal of waste. To do this effectively, equipment are needed. Hence, the short supply of adequate and functional waste management equipment e.g. mechanical shovel, storage containers etc in the Nigerian industries has brought setback to industrial waste management in our industries. Since the equipment is not available locally, they are not easily substituted to get work going. The resultant effect is inefficiency in industrial waste management (Ademji & Karibo 2008).
Poor implementation of relevant environmental laws /regulations
According to Olojoba (2009), it was started that though there has been environmental sound policy such as mentioned earlier in section 20.33; 34.7.8 of this research write-up guiding the quality of waste generation and effluent disposal into the environment, most industries are yet to do so, still dispose their waste without treatment, only to be removed and dumped elsewhere. This shows that the implementation strategy of the policy is said to be weak or inefficient.
Non-involvement of industries in the management of waste
According to Olojoba (2009), the cradle to grave principles of the Department of Petroleum Resources (DPR), should be applied to all industries generating waste. The effective management of such waste till its final disposing site especially of untreated effluent. Non-involvement of industries in Nigeria has lead to indiscriminate dumping of hazardous effluent thereby causing harm to humans and other materials.
The impact of industrial effluent disposal on the environment
It is of great importance that effective waste disposal in industries be put in high esteem since it affects the environment making it to become unfriendly to man and thus affect “health”.
Below are the impacts of effluent disposal on the environment which calls for urgent attention in other to intervene in the light of this;
- Industrial activities carried out in developing countries such as Nigeria with weak legal framework and regulation infrastructure has led to pollution of water resources, destruction of fauna and flora, health hazards and deterioration of health quality, air and noise pollution, as well as destruction of traditional economic infrastructures within communities hosting some of these high powered investments (Ifeanyi, 2002; Eneh and Okezie, 2009; Eneh, 2008, 2011).
- Environmental pollution and degradation attendant upon exploration activities in Niger Delta region in Southern Nigeria have generated political, social, health, economic, insecurity and other developmental challenges of national and international dimension (Ifeanyi, 2002).
References
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African Development Bank (2002). Study on Solid Waste Management Options for Africa Project Report, final draft version, 2002. Retrieved on 7th Nov. 2010 from http//www.afdb.org/pls/portallurl.
Aniefiok, M. (2004). Evaluation of Solid Waste Management Options. Journal of Environmental Health. A publication of Society for Environmental Health of Nigeria (SEHON) Vol. 1; 27-32.
Ejoor, D. (2004). The Origin of Urhobo Nation. Erewko P. Egbosun Press, Delta State.
Environmental Protection Agency (2001). The Consumer Handbook for Reducing Waste. Washington DC, United State EPA.
Gupta, M. C. & Mahajan (2005). Textbook of Preventive and Social Medicine. Ghana: Jaypee Brothers Medical Publishers (P) Ltd.
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