Augustine Ifelebuegu

THE FATE AND BEHAVIOR OF SELECTED ENDOCRINE DISRUPTING CHEMICALS IN FULL SCALE WASTEWATER AND SLUDGE TREATMENT UNIT PROCESSES

Endocrine disrupting chemicals are discharged into the environment mainly through wastewater treatment processes. There is a need for better understanding of the fate of these compounds in the unit processes of treatment plant to optimise their removal. The fate of oestrone, 17β-estradiol, 17α-ethinyestradiol and nonylphenol in the unit processes of full scale wastewater treatment plants in the UK, including activated sludge plant, oxidation ditch, biofilter and rotating biological contactor were investigated. The overall removal efficiencies of all the compounds ranged from 41 %to 100%. The removals were predominantly during the secondary biological treatment with the rates of removal related to the nitrification rates and the sludge age. The removal efficiency of the treatment processes were in the order activated sludge > oxidation ditch > biofilter > rotating biological contactors. Activated sludge plant configured for biological nutrient removal showed better removal of the endocrine disrupting chemicals compared to conventional activated sludge plant effluents. Tertiary treatment was also significant in the removal process through solids removal. Overall mechanisms of removal were biodegradation and sorption unto sludge biomass. Phytoremediation was also significant in the removal processes. The endocrine disrupting chemicals persisted in the anaerobic sludge digestion process with percentage removals ranging fro 10–48 %. Sorption of the endocrine disrupting chemicals onto the sludge increased with increasing values for the partitioning coefficients and the organic carbon contents of the sludge.

Removal of an Endocrine Disrupting Chemical (17α-ethinyloestradiol) from Wastewater Effluent by Activated Carbon Adsorption: Effects of Activated Carbon Type and Competitive Adsorption

Granular activated carbon has been extensively used for the adsorption of organic micropollutants for potable water production. In this study the removal of an endocrine disrupting chemical from wastewater final effluent by three types of granular activated carbon (wood, coconut and coal based) has been investigated in batch adsorption experiments and correlated with the removal of chemical oxygen demand (COD), total organic carbon (TOC) and ultraviolet absorbance (UV). The results obtained demonstrated 17α-ethinyloestradiol (EE2) removals of 98.6%, 99.3%, and 96.4% were achieved by the coal based (ACo), coconut based (ACn) and wood based (AWd) carbons respectively at the lowest dose of carbon (0.1gl−1). The other adsorbates investigated all exhibited good removal. At an equilibrium concentration of 7mgl−1 the COD adsorption capacities were 3.16mg g−1, 4.8 mg g−1 and 7.1 mg g−1 for the wood, coconut and coal based carbons respectively. Overall, the order of removal efficiency of EE2 and the other adsorbates for the three activated carbons was ACn > ACo > AWd. The adsorption capacities of the carbons were found to be reduced by the effects of other competing adsorbates in the wastewater effluent.

Mechanistic evaluation of the sorption properties of endocrine disrupting chemicals in sewage sludge biomass.

This study investigated the sorption behaviour of two endocrine disrupting chemicals; 17β-estradiol (E2) and 17β-ethinylestradiol and their thermodynamic properties in an activated sludge biomass. The partition coefficient values measured for E2 and EE2 at varying temperatures range from 245–604 L/kg ( log Kd 2.39–2.78) and 267–631 L/kg (Log Kd 2.43–2.80), respectively. The Kd values were inversely related to temperature. The average percentages of E2 and EE2 adsorbed to the solid phase at 4.3 % dry solid were 87.2 % and 92.5 %, respectively. Sorption of E2 and EE2 to the activated sludge biomass was found to be spontaneous and entropy retarded with ΔG values in the range of −13 to −16 KJ/mol and ΔS value of−105.2J/mol/K and 96.7 J/mol/k for E2 and EE2, respectively. The enthalpy changes for E2 and EE2 were −45.7KJ/mol and −43.4KJ/mol respectively, demonstrating that the sorption process is exothermic. The values of the enthalpy changes also show that the mechanism of sorption is physisorption with some element of chemisorption.

Human factors analysis and classification system for the oil and gas industry (HFACS-OGI)

The oil and gas industry has been beset with several catastrophic accidents, most of which have been attributed to organisational and operational human factor errors. The current HFACS developed for the aviation industry, cannot be used to simultaneously analyse regulatory deficiencies and emerging violation issues, such as sabotage in the oil and gas industry. This paper presents an attempt to improve the existing HFACS investigation tool and proposes a novel HFACS named the Human Factors Analysis and Classification System for the Oil and Gas Industry (HFACS-OGI). Results found the HFACS-OGI system to be suitable for categorising accidents, following the analysis of 11 accident reports from the US Chemical Safety Board (US CSB). The HFACS-OGI system moreover revealed some significant relationships between the different categories. Furthermore, the results indicated that failures in national and international industry regulatory standards would automatically create the preconditions for accidents to occur.

Nonconventional low-cost cellulose- and keratin-based biopolymeric sorbents for oil/water separation and spill cleanup: A review

ABSTRACT Oil spills remain an inevitable risk in the exploration, production, and transportation of hydrocarbons. Their impacts on the environment are usually severe, hence effective and efficient response strategies are essential to minimise environmental damage. Conventional synthetic oil sorbents are the most widely used sorbents for spill cleanup but are usually expensive and non-biodegradable. Low-cost nonconventional biopolymeric sorbents are now emerging as alternatives to conventional sorbents used in oil spill cleanup owing to their availability and eco-friendliness. In this review, we present low-cost nonconventional cellulose- and keratin-based biopolymeric oil sorbents highlighting their oil sorption capacities, properties, and mechanisms.

Environmental effects of crude oil spill on the physicochemical and hydrobiological characteristics of the Nun River, Niger Delta

Oil spill pollution has remained a source of several international litigations in the Niger Delta region of Nigeria. In this paper, we examined the impacts of small recurrent crude oil spills on the physicochemical, microbial and hydrobiological properties of the Nun River, a primary source of drinking water, food and recreational activities for communities in the region. Samples were collected from six sampling points along the stretch of the lower Nun River over a 3-week period. Temperature, pH salinity, turbidity, total suspended solids, total dissolved solids, dissolved oxygen, phosphate, nitrate, heavy metals, BTEX, PAHs and microbial and plankton contents were assessed to ascertain the quality and level of deterioration of the river. The results obtained were compared with the baseline data from studies, national and international standards. The results of the physicochemical parameters indicated a significant deterioration of the river quality due to oil production activities. Turbidity, TDS, TSS, DO, conductivity and heavy metals (Cd, Cr, Cu, Pb, Ni and Zn) were in breach of the national and international limits for drinking water aquatic health. They were also significantly higher than the initial baseline conditions of the river. Also, there were noticeable changes in the phytoplankton, zooplankton and microbial diversities due to oil pollution across the sampling zones.

Renewable Energy in Africa: Policies, Sustainability, and Affordability

Africa is endowed with significant renewable energy resources: abundant biomass, wind, hydropower, geothermal, and solar energy. However, these huge potentials remain largely unexploited, with Sub-Saharan Africa having the world’s lowest electricity access rate, at only about 24%. The level of investment and policy interest in renewable energy remains low. A major challenge to Africa’s efforts to develop renewable energy sources and the associated technologies is cost. Affordability is, therefore, a major consideration in the development/uptake of renewable energy technologies and depends mainly on the type of technology, policy direction, sustainability, and investment considerations. This chapter will review the policies and policy direction of African countries on renewable energy and the factors that affect the affordability of the technologies currently and in the future.

Low cost sustainable materials for grey water reclamation

Grey water reclamation is a sustainable solution for managing water shortages. However, grey water contains high levels of detergents, particularly surfactants, which alongside other chemical constituents can pose a serious risk to human health and the environment. Biological treatments are not effective in the treatment of grey water since the detergents inhibit the activities of microorganisms. Chemical treatment options have an impact on public perception and could be cost prohibitive for domestic and small scale reuse applications. In this paper, we review the characterization of the constituents of grey water and the application of various low cost sustainable materials such as zeolite, activated carbon, mussel shells, tyre granules, fly ash, ground granulated blast furnace slag and silica gel for the treatment and removal of detergent characteristics.

Analysis of Penalties Imposed on Organisations for Breaching Safety and Health Regulations in the United Kingdom

Background The study analyzes penalties imposed on organizations for breaching safety and health regulations. The research questions are as follows: what are the commonly breached safety and health regulations? How proportional are penalties imposed on organizations for breaching health and safety regulations in the United Kingdom? Methods The study employed sequential explanatory mixed research strategies for better understanding of health and safety penalties imposed on organizations. Actual health and safety convictions and penalties data for 10 years (2006 to 2016) were obtained through the United Kingdom Health and Safety Executive (HSE) public register for convictions. Overall, 2,217 health and safety cases were analyzed amounting to total fines of £37,179,916, in addition to other wide-ranging penalties. For thorough understanding, eight interviews were conducted with industry practitioners, lawyers, and HSE officials as part of the study qualitative data. Results Findings show that the Health and Safety at Work (HSW) Act accounted for 46% of all HSE prosecution cases in the last decade. This is nearly half of the total safety and health at work prosecutions. Moreover, there is widespread desire for organizations to comply with the HSW Act, but route fines are seen as burdensome and inimical to business growth. Conclusion A key deduction from the study reveal significant disproportionality concerning penalties imposed on organizations for breaching safety and health regulations. On aggregate, small companies tend to pay more for health and safety offenses in a ratio of 1:2 compared to large companies. The study also reveals that the HSW Act accounted for nearly half of the total safety and health at work prosecutions in the last decade.