Evaluation of the Influence of Reactor Design on the Treatment Performance of an Optimized Pilot-Scale Waste Stabilization Pond

Waste stabilization pond (WSP) is globally one of the most popular wastewater treatment options due to its high efficiency and low cost. A field scale prototype was designed and scaled down to a pilot-scale model using dimensional analysis in the development of the foot print size. Pilot-scale reactors were built with the specifications produced from literature suggested reactor geometric configurations and experimental study was conducted to evaluate the performance of optimized pilot-scale WSP configurations. The optimized pilot scale WSPs consisted of an anaerobic, facultative, and a maturation stage with varying baffle orientation, length to width ratio, and depth. Comparisons were made on the optimized pilot-scale WSP reactors. The removal performance of the experimental test was based on a number of parameters (Faecal coliform, pH, TDS, and Conductivity). Results showed that the significantly lower cost design displayed slightly better removal performance compared to other WSP design developed from literature data. This paper covers a relevant subject within the field of waste stabilization ponds, namely the representation of the influence of reactor design on the treatment performance of WSP

Assessment of wash program in public secondary schools in south-western Nigeria

The provision of safe water, sanitation and hygiene in schools has been established to improve health, boost educational achievement, and promote gender equity which has a positive impact on the society. The aim of this pilot study is to ascertain the state of WASH program in public secondary schools in South-Western Nigeria. A total of twelve schools which span across three Local Government areas in two States (Lagos and Ogun), in South-Western Nigeria were selected. The standard for WASH in schools by UNICEF was used as the guiding principles to evaluate the adequacy of the various WASH components. Out of the 12 public secondary schools visited, only 3 (25%) had drinking water points (boreholes) and 40% of the schools do not have separate latrines for boys and girls, and for promoting privacy of older girls. Only 1 (10%) of the schools had hand washing points but without soap and there is no plan in the schools for advancing WASH program. This study reveals that the present WASH practice in many of the schools is not adequate

Rainfall-Runoff Relationships and flow forecasting, Ogun river Nigeria

An excess or a lack of rainfall are the major causes of most hydrological hazards, and the need for a systematic approach to river flow forecasting based on rainfall is imperative, especially in Nigeria. A study was carried out on three major gauging stations of the Ogun river basin to determine the rainfall-discharge relationship and model equations for use in the basin and similar basins. Stream flow and rainfall data for at least seven consecutive years for each station were collected and analyzed. The rainfall-runoff data were subjected to linear, exponential and higher order analysis. Stream flow data were also fitted to normal, log-normal and log-Pearson Type III distributions. The selection of the appropriate probability distribution model for each gauging station was based on graphical comparisons between observed and predicted flows and goodness-of-fit tests using chi-square and probability correlation coefficients. Results show that model equations with logarithmic and exponential relationships between rainfall and discharge gave better and more realistic prediction estimates and can be used for the basin. It was determined that the peak discharges occurred when the rainfall values were at their maximum, and a distinct relationship between the discharge and rainfall exists at each of the gauging stations

Environment, Health and Wealth: Towards an Analysis of Municipal Solid Waste Management in Ota, Ogun State, Nigeria

The management of municipal solid waste is one of the challenges facing the developing countries because governments, institutions, and private sectors have given solid waste management low priority and ignoring the implication it has on the general public. This is characterized by inefficient collection methods, insufficient coverage of the collection system and improper disposal. This paper presents the current solid waste management method adopted in Ado-Odo Ota local government and its associated challenges. Four locations (Iganmode area, Joju area, Ota market and toll gate area) were selected. These sites are points where the waste bins are located. A field work that involves the characterization and types of the waste generated, and frequency of collection from each site was carried out. A representative sample of 280 kg was used for the waste characterization and the result shows that about 64% of the wastes are recyclable with lots of organic waste that comprises of food and agricultural waste which can be used as compost. The only dump site in Ota was visited in order to obtain useful information concerning the present state of solid waste management. The study revealed that there is presently no investment made to the existing development plan to introduce a modern waste management system. The study suggests new approach that could be used by institutions and government agencies for municipal solid waste management to achieve sustainable and effective sanitation

Hydraulic Modelling and Optimization of a Wastewater Treatment System for Developing Nations Using Computational Fluid Dynamics

Waste stabilization pond (WSP) is globally one of the most popular wastewater treatment options because of its high efficiency and low cost. However, no rigorous assessment of WSPs that account for cost in addition to hydrodynamics and treatment efficiency has been performed. A study was conducted that utilized Computational Fluid Dynamics (CFD) coupled with an optimization program to optimize the selection of the best WSP configuration based on cost and treatment efficiency. Several designs generated by the CFD/optimization model showed that both shorter and longer baffles, alternative depths, and reactor length to width ratios could improve the hydraulic efficiency of the ponds at a reduced overall construction cost. In addition, a study was conducted on the optimized WSP which consisted of an anaerobic, facultative, and a maturation stage whose baffle orientation, length to width ratio, was specified by a CFD model prediction and was compared with a three stage WSP designed according to literature suggested reactor geometric configurations. Experimental tests were performed on a pilot scale version of the threestage WSP where the removal performance was based on a number of parameters (Faecal coliform, pH, TDS, and Conductivity). Results showed that the significantly lower cost design based on the optimized CFD simulations displayed slightly better removal performance compared to the standard WSP design developed from literature data. The results of this study clearly showed that unit treatment process designs based on rigorous numerical optimization can aid in producing cost effective designs that make it more possible for developing nations to incorporate adequate and effective sanitation

Integrating Water, Sanitation and Hygiene (WaSH) Program into Educational Institutions Policy in Nigeria.

The provision of safe water, sanitation and hygiene (WASH) in educational institutions has been established to improve health, boost educational achievement, and promote gender equity which has a positive impact on the society. However, most public secondary schools in Nigeria are short of the basic water and sanitation facilities, and hygiene education programs are often inadequate. The aim of this study is to ascertain the state of WASH program in the educational institutions. This was assessed by investigating the causes of inadequate potable water supply, poor sanitation and deficient hygiene education in public secondary schools. A total of fifteen schools were selected for the study which span across three Cities (Lagos, Abeokuta and Ota) in two States (Lagos and Ogun), in South-Western Nigeria. The standard for WASH in schools by UNICEF was used as the guiding principles to evaluate the adequacy of the various WASH components. Out of the 12 public secondary schools visited, only 3 (25%) had drinking water points (boreholes) and 40% of the schools do not have separate latrines for boys and girls. Only 1 (10%) of the schools had hand washing points but without soap. One school reported giving hygiene talk once in a term whereas there are no facilities and program in the schools for promoting safety, privacy and security of older girls. In all the schools, open dump system of solid waste disposal that are not properly managed is the general practice. This study reveals that the present WASH facilities and practices in many of the schools are not satisfactory. Therefore, to maximize the potential of students as the most persuasive advocates of good WASH practices in the society, it is necessary to integrate WASH program into national education policy and schools should be provided with adequate facilities.