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Honey is a sweet substance made by bees using nectar from flowers. Honey is of different types, but the Apis mellifera is the one most commonly used, consumed by people and collected by bee keepers. The flower from which bees gather nectar, determines the colour, chemical composition, flavour and aroma of the honey. The use of honey in folk medicine has been practiced since ancient times and has more recently been rediscovered by medical researchers for its use in dressing acute and chronic wounds, particularly where conventional modern therapeutic agents have failed. The wound healing property of honey is due to its antibacterial activity; the ability to maintain a moist wound condition, the high sugar content which hinders microbial growth, the high viscosity which help in providing a protective barrier to prevent infection, the immunomodulatory property which helps in wound repair, the enzymatic production of hydrogen peroxide and the high osmolarity which draws fluid out of the wound bed to enable an outflow of lymph, as occurs with negative pressure wound therapy. Different scientists reported honey, as having one of the most powerful inhibitory effect with regard to sixty species of bacteria. Although the inhibitory activity of honey has been established against wide spectrum of bacteria, it differs depending on the type of honey. Under different concentrations, honey has been reported to be active against a number of bacterial pathogens such as (Escherichia coli, Pseudomonas aeruginosa, Klebsiella, Salmonella, Shigella, Enterobacter and Coagulase positive/ negative Staphylococcus etc.) isolated from wounds.

Cleaner production is the key to environmental sustainability. Conversion of crude oil to various beneficial products is responsible for the contamination of air, water, and soil which are harmful to human, plants, animals, public health and the environment. Adequately treating produced water is beneficial for irrigation, wildlife consumption, industrial water and for domestic purposes. Therefore, green technology for treatment of crude oil processed water would provide the environmental friendliness needed for prolong utilization of our natural resources. Hence, the aim of this book chapter is to investigate the potentials of constructed wetland as a promising, effective and environmentally friendly alternative for secondary petroleum refinery wastewater treatment. Planted and unplanted mesocosm scale experiment with real secondary refinery wastewater was used for the purpose of the study. The parameters investigated were temperature, pH, dissolved oxygen, electrical conductivity, total suspended solids, carbon oxygen demand, total petroleum hydrocarbon and oil and grease. The results revealed that Typha latifolia planted VSSF CWs effectively treated organic contaminants in secondary refinery wastewater with a better performance than the unplanted control VSSF CWs. The chromatographs for wastewater and T. latifolia samples showed a hydrocarbon distribution between n-C9 to n-C24 indicating abundance of lower weight hydrocarbon contamination.

Cleaner production is the key to environmental sustainability. Conversion of crude oil to various beneficial products is responsible for the contamination of air, water, and soil which are harmful to human, plants, animals, public health and the environment. Adequately treating produced water is beneficial for irrigation, wildlife consumption, industrial water and for domestic purposes. Therefore, green technology for treatment of crude oil processed water would provide the environmental friendliness needed for prolong utilization of our natural resources. Hence, the aim of this book chapter is to investigate the potentials of constructed wetland as a promising, effective and environmentally friendly alternative for secondary petroleum refinery wastewater treatment. Planted and unplanted mesocosm scale experiment with real secondary refinery wastewater was used for the purpose of the study. The parameters investigated were temperature, pH, dissolved oxygen, electrical conductivity, total suspended solids, carbon oxygen demand, total petroleum hydrocarbon and oil and grease. The results revealed that Typha latifolia planted VSSF CWs effectively treated organic contaminants in secondary refinery wastewater with a better performance than the unplanted control VSSF CWs. The chromatographs for wastewater and T. latifolia samples showed a hydrocarbon distribution between n-C9 to n-C24 indicating abundance of lower weight hydrocarbon contamination.

A duplex constructed wetland (duplex-CW) is a hybrid system that combines a vertical flow (VF) CW as a first stage with a horizontal flow filter (HFF) as a second stage for a more efficient wastewater treatment as compared to traditional constructed wetlands. This study evaluated the potential of the hybrid CW system to treat influent wastewater containing diesel range organic compounds varying from C7 – C40 using a series of 12-week practical and numerical experiments under controlled conditions in a greenhouse (pH was kept at 7.0 ± 0.2, temperature between 20 and 23° C and light intensity between 85 and 100-μmol photons m−2 sec−1 for 16 h d−1). The VF CWs were planted with Phragmites australis and were spiked with different concentrations of NH4+-N (10, 30 and 60 mg/L) and PO43--P (3, 6 and 12 mg/L) to analyse their effects on the degradation of the supplied petroleum hydrocarbons. The removal rate of the diesel range organics considering the different NH4+-N and PO43--P concentrations were simulated using Monod degradation kinetics. The simulated results compared well with the observed database. The results showed that the model can effectively be used to predict biochemical transformation and degradation of diesel range organic compounds along with nutrient amendment in duplex constructed wetlands.

This study examined the performance of pilot-scale vertical subsurface flow constructed wetlands (VSF-CWs) planted with three indigenous plants, i.e. Typha latifolia, Cyperus alternifolius, and Cynodon dactylon, in removing heavy metals from secondary treated refinery wastewater under tropical conditions. The T. latifolia-planted VSF-CW had the best heavy metal removal performance, followed by the Cyperus alternifolius-planted VSF-CW and then the Cynodon dactylon-planted VSF-CW. The data indicated that Cu, Cr, Zn, Pb, Cd, and Fe were accumulated in the plants at all the three VSF-CWs. However, the accumulation of the heavy metals in the plants accounted for only a rather small fraction (0.09-16%) of the overall heavy metal removal by the wetlands. The plant roots accumulated the highest amount of heavy metals, followed by the leaves, and then the stem. Cr and Fe were mainly retained in the roots of T. latifolia, Cyperus alternifolius, and Cynodon dactylon (TF < 1), meaning that Cr and Fe were only partially transported to the leaves of these plants. This study showed that VSF-CWs planted with T. latifolia, Cyperus Alternifolius, and Cynodon dactylon can be used for the large-scale removal of heavy metals from secondary refinery wastewater.

The pollution of waterbodies and the environment by the petroleum industry is of particular concern in Nigeria. This problem can be addressed by the application of a constructed wetland (CW) which is a naturebased system that is simple to construct, has low operational and maintenance costs in terms of supply of energy and periodic maintenance. The application of CWs in Nigeria for polishing of petroleum refinery wastewater is an unprecedented research. This PhD thesis focused on some specific objectives which were characterization of treated secondary refinery wastewater, design, construction, operation and monitoring of planted (T. latifolia, C. alternifolius and C. dactylon) and unplanted vertical subsurface flow, horizontal subsurface flow and hybrid CWs for the removal of suspended solids, nutrients,heavy metals, organic matter and organic pollutants. The CWs effectively treated the petroleum contaminated wastewater to effluent compliance limits. In this study, T. latifolia planted CWs had consistently higher removal efficiencies for all the measured parameters than C. alternifolius and C. dactylon planted CW systems. Therefore, in order to improve the wastewater quality discharged by the Kaduna Refining and Petrochemical Company (KRPC) and meet the stringent guidelines as well as protect the recipient streams, installation of CWs at the effluent discharge point of KRPC is strongly recommended.

Typha latifolia-planted vertical subsurface flow constructed wetlands (VSSF CWs) can be used to treat petroleum refinery wastewater. This study evaluated if the removal efficiency of VSSF CWs can be improved by changing the plant species or coupling horizontal subsurface flow constructed wetlands (HSSF CWs) to the VSSF CW systems. The VSSF CWs had a removal efficiency of 76% for biological oxygen demand (BOD5), 73% for chemical oxygen demand (COD), 70% for ammonium-N (NH4+-N), 68% for nitrate-N (NO3−-N), 49% for phosphate (PO43−-P), 68% for total suspended solids (TSS), and 89% for turbidity. The HSSF CWs planted with T. latifolia further reduced the contaminant load of the VSSF CW-treated effluent, giving an additional removal efficiency of 74, 65, 43, 65, 58, 50, and 75% for, respectively, BOD5, COD, NH4+-N, NO3−-N, PO43−-P, TSS, and turbidity. The combined hybrid CW showed, therefore, an improved effluent quality with overall removal efficiencies of, respectively, 94% for BOD5, 88% for COD, 84% for NH4+-N, 89% for NO3−-N, 78% for PO43−-P, 85% for TSS, and 97% for turbidity. T. latifolia strived well in the VSSF and HSSF CWs, which may have contributed to the high NH4 +-N, NO3−-N, and PO43−-P removal efficiencies. T. latifolia-planted VSSF CWs showed a higher contaminant removal efficiency compared to the unplanted VSSF CW. T. latifolia is thus a suitable plant species for treatment of secondary refinery wastewater. Also a T. latifolia-planted hybrid CW is a viable alternative for the treatment of secondary refinery wastewater under the prevailing climatic conditions in Nigeria.

Typha latifolia-planted vertical subsurface flow constructed wetlands (VSSF CWs) and an unplanted microcosm constructed wetland were used for treating secondary refinery wastewater from the Kaduna Refining and Petrochemical Company (KRPC, Nigeria). Cow dung was applied to the planted wetlands at the start of the experiment and after 3 months to enhance plant growth and petroleum degradation. The T. latifolia-planted VSSF CWs removed 45–99% total petroleum hydrocarbon (TPH), 99–100% phenol, 70–80% oil and grease, 45–91% chemical oxygen demand (COD), and 46–88% total suspended solids (TSSs). The performance of the unplanted control VSSF CW achieved lower removal efficiencies (15–58% TPH, 86–91% phenol, 16–44% oil and grease, 24–66% COD, and 20–55% TSS). T. latifolia plants had a bioaccumulation factor (BAF) > 1 for phenol, total nitrogen (TN), and total phosphate (TP), suggesting a high removal performance for these contaminants and good translocation ability (TF) for TPH, phenol, oil and grease, and TN, with the exception of TP which was mainly retained in their roots (BAF = 47). This study showed T. latifolia is a good candidate plant to be used in VSSF CWs for polishing secondary refinery wastewater in developing countries.

Petroleum refining industries extract large volumes of freshwater for the process of refining crude oil. Thus, large volumes of wastewater are generated. These wastewaters contain contaminants that are neurotoxic, carcinogenic and mutagenic. Petroleum-related industries have to comply with strict regulations by regulatory authorities; these have led them to explore many treatment technologies for effluent management. However, conventional wastewater treatment technologies have higher energy and capital requirement than biological treatment systems. In addition, their processes can lead to incomplete decomposition of contaminants which can generate by-products that are often toxic to both humans and the environment. Thus, these by-products require further treatment.

Secondary wastewater discharged by the Kaduna refining and petrochemical company in Kaduna (Nigeria) was characterized and treated in six vertical subsurface flow constructed wetlands (VSF CW) under field conditions. The secondary refinery wastewater had high levels of BOD (106 ± 58.9 mg/L), COD (232 ± 121.2 mg/L), TSS (86.1 ± 99.7 mg/L), TDS (278.8 ± 112.7 mg/L) and a turbidity of 56.8 ± 59.2 NTU. Cyperus alternifolius and Cynodon dactylon (L.) Pers. were planted in four VSF CWs and the last two VSF CWs served as the unplanted control. Good reduction efficiencies in the concentration of the contaminants were achieved which corresponds to removal rates of 54%, 85%, 68%, 65%, 68%, 58% and 43% for TDS, turbidity, BOD, COD, ammonium-N, nitrate-N and phosphate-P respectively, for the C. alternifolius planted vertical flow constructed wetland and 50%, 82%, 70%, 63%, 49%, 54% and 42% for the C. dactylon planted wetland system. Hence, C. alternifolius and C. dactylon planted VSF CWs were shown capable of treating secondary refinery effluent to discharge permit limits. For most of the parameters considered, the performance of the C. alternifolius and C. dactylon planted vertical flow constructed wetland systems was not significantly different from each other, however, they performed significantly better than the unplanted control.

This paper examines the impact of the Community-Based Poverty Reduction Project (CPRP) in alleviating poverty in selected benefiting communities in Yobe State. Purposive and simple random sampling was used to select the area of study and respondents. Questionnaires, Focus Group Discussion and Key Informants Interview were also used to collect data. The data was presented by the use of simple percentage and frequency tables, graphs and charts. Data was analysed through the use of ANOVA. The discourse, guided by the Basic Needs Theory found out that even though the concept for which the CPRP was adopted has been achieved, e.g. community participation and provision of 838 micro-projects in the whole of Yobe State, the micro-projects or basic needs infrastructure implemented are not adequate and wide-spread enough to reduce poverty in concrete terms. It however reduced the stress of people in accessing some basic needs e.g. water supply in some communities. The paper recommends that to effectively achieve poverty reduction, there should be sustained commitment of funding and maintenance of projects by respective stakeholders for holistic and widespread approach to poverty reduction in Yobe State. Nonetheless, this paper maintains that the CPRP poverty reduction intervention is a viable tool for the provision of basic needs infrastructure in rural communities to set the path for development of Yobe State.