THE EFFECT OF NPK AND UREA ON THE BIOREMEDIATION OF CRUDE OIL CONTAMINATED WATER
CHAPTER ONE INTRODUCTION
1.1 Background of study
For many years now and many more years to come, the aquatic environment have served (and will continual to serve) as a stable habitat to various species of plant and animals ranging from the micro-cellular zooplankton to the more complex species of fishes and birds. Over the year a natural resource (crude oil) has been found present both on land and on sea. In Nigeria alone there are about 606 oil fields in the Niger Delta, of which 360 are on-shore and 246 off-shore (Nwilo and Badejo, 2005). Boasting herself as the largest oil-producing country in Africa and sixth in the world.
This precious natural resources initially was used as a means of illumination and lubrication of machine parts against friction but ever since the invention of the automobile industry and the internal combustion energy, the demand for this product has increased rapidly. Currently, there are many challenges associated with the transportation, stockpiling, distribution and production of this raw materials and its various fractions. In an attempt to make this commodity reading available for usage, various pollution activities has sufficed ranging from the contamination of both water and soil environment either by deliberate vandalizing of oil pipeline used for the transport of crude oil, to the fallout of ships transporting crude oil from an on-shore to the jetty thereby creating an unbalanced and stressed aquatic environment.
The effects of this pollution includes, decreasing the population of aquatic wildlife , making the water environment unsuitable for domestic and commercial purpose, also the reduction on the availability of oxygen necessary for growth thus causing death, and the evaporation of high volatile fraction thus making the site a potential fire outbreak area. Various clean-up method like the application of chemical dispersants and controlled burning serves but with little effectiveness as the atmosphere becomes heavily polluted as in the case of burning and an increase in greenhouse gases (GHG) also harms the climate. Also by introducing chemical dispersants the toxicity of the environment is increased even though the spill is treated, it ‘in returns’ pollutes the environment.
With a purpose of developing a cleaner and safe technology for the treatment of crude oil pollution, microbiologist came up with a natural model which could be stimulated to achieve fast and safer result. Bioremediation is often referred to as the most natural method of eliminating large amount of oil contaminants from the environment with the use of a naturally occurring micro- organism to degrade hazardous crude substance into less toxic or non-toxic compounds. It is worthy of note that bioremediation is an optimization of a natural process of biodegradation where micro-organism chemically alter and break down organic molecules in other substance such as carbon dioxide, fatty acids and water in order to obtain energy and nutrients. Under bioremediation two distinct processes may be applied to speed and enhance the process. They include Biostimulation and Bioaugmentation. Bioaugmentation involves the addition or application of Hydrocarbon utilizing micro-organism thereby increasing the microbial population responsible for the clean-up of the polluted site. Specific bacteria and fungi can be used in this process but bacteria are more commonly used. Biostimulation involves the addition of appropriate microbial nutrients to a polluted site to increase the microbial activities of indigenous microbial flora. Some useful bacteria involved in bioremediation includes pseudomonas, aeromonas, Moraxella, Bilejerirckia, chrobacter, Nocardia, Streptomyces. In this study the effect of Nutrients specifically Urea and Nitrogen, Phosphorus and Potassium (N.P.K) on bioremediation will be examined.
1.2 Statement of problem
Due to the ever increasing demand globally for crude oil and its various fractions, pollution of crude oil and its various fractions on both land and sea has been a major challenge associated with this industry. The need for a cleaner and better technology which would create a cleaner environment for aquatic wildlife and terrestrial organization has placed a call for the clean-up technology of bioremediation. On a crude oil contaminated site, the number of microbes’ present increases rapidly without a subsequent increase in the nutrients available in the soil or aquatic body, thus a challenge of insufficient nutrients for proper bioremediation.
Hence, this research studies the effect of the addition of Nitrogen,Phosphorus,Potassium(N.P.K) fertilizer and Urea nutrients to contaminated crude oil water with a cultured stain of bacteria of the pseudomonas sp on the rate of bioremediation. This biotechnology is very promising as it makes land or aquatic environment habitable again after the treatment has been carried out.
1.3 Aim and Objectives of the Project
To study the effect of urea and N.P.K on the bioremediation of crude oil-contaminated water.TO achieve this, the following activities were defined and carried out:
To synthesize a crude oil contaminated water. To culture pseudomonas aeroginosa bacteria. To apply nutrients to this synthesized crude oil contaminated water containing cultured bacteria To prepare samples with varying quantity of nutrients. To observe the effect of the nutrients in the crude oil-contaminated water. To determine the Residue Hydrocarbon Content (RHC) in the crude contaminated water.
1.4 Significance of the work
This method of crude oil contamination clean-up is very effective in that it utilizes naturally occurring micro-organism capable of ‘eating up’ crude oil and its various fraction depending on some environmental factors which may include availability of adequate nutrients in the contaminated site. A thorough understanding of the bioremediation process and the responsible micro-organism would in a long run help in solving the problem of oil pollution associated with the oil industry when applied. The proportions of combination of the nutrients to achieve a balance concentration in the aquatic environment to be added to any environment so as not lead to eutrophication and so enhance the bioremediation of crude oil contained site. The importance of this study would lead to a great reduction in the effects of the pollution caused by oil spill in Nigeria and the world at large and facilitate the quick recovery of such site and make them habitable in the shortest possible time.
1.5 Scope of Research
This research would consider primarily the biostimulation aspect of bioremediation of crude oil-contaminated water. Nutrients like Nitrogen Phosphorus Potassium (N.P.K) fertilizer and Urea would be added to an artificially contaminated crude oil-water to carry out the study.