African Journal of Environmental and Waste Management

African Journal of Environmental and Waste Management ISSN 2375-1266 Vol. 6 (6), pp. 001-010, June, 2019. © International Scholars Journals

Full Length Research Paper

Impact of enhanced flow on the flow system and wastewater characteristics of sewage-fed fisheries in India

Pankaj Kumar Roy*, Arunabha Majumder, Asis Mazumdar, Mrinmoy Majumder and Malabika Biswas Roy

School of Water Resources Engineering, Jadavpur University, Kolkata-700 032, India.

Accepted 21 May, 2019

Abstract

In this study, we estimated the impact of enhanced flow on shallow wetlands that receive major effluent discharge from an adjoining metropolitan city. The local people use the shallow wetlands for pisciculture. Beginning in 1998, the population of the city began to rise and the amount of effluent discharge increased. The excess load is now a problem for the city engineers, and they plan to manage the sewage by increasing the area of the sewage network. The depth of the wetlands is also decreasing due to an increase in suspended solids. The quantity of the toxic load suspended in the discharge has increased the silt content, which has consequently further reduced the depth of the wetlands. The excess flow on low depth wetlands may cause overflows and destroy both the ecosystem and the livelihood of the local people. In this study, the pattern identification capability of neuro-genetic models was used to estimate the impact of the excess flow on sewage-fed wetlands. Two neural network models were created to estimate whether fisheries can accommodate the enhanced flow. According to the results of this study, the East Kolkata Wetlands, India can accommodate 1450 million litres per day (MLD) of sewage, if the average depth of water is increased to 1.18 m.

Key words: Dry weather flow, East Kolkata wetlands, neural network, sewage-fed fisheries.

African Journal of Environmental and Waste Management ISSN 2375-1266 Vol. 6 (6), pp. 001-011, June, 2019. © International Scholars Journals

Full Length Research Paper

Growth and yield potential of Echinochloa pyramidalis (Lam.) Hitchc & Chase: A forage plant used in vertical-flow constructed wetlands in Cameroon

Marie-Madeleine NGOUTANE PARE¹*, Doulaye KONE², Ives Magloire KENGNE¹ and Amougou AKOA¹

¹Wastewater Research Unit, P. O. Box 8404, University of Yaoundé I, Cameroon.

²Department of Water and Sanitation in Developing Countries (Sandec), Eawag: Swiss Federal Institute of Aquatic Science and Technology, Ueberlandstrasse, 133 CH-8600 Dübendorf, Switzerland.

Accepted 27 March, 2019

Abstract

This work aims at assessing growth and productivity of Echinochloa pyramidalis in the saline and saline-flooded processes of wetland treatment. Growth characteristics such as density, number of dead plants, height and number of new shoots and biomass production of the plant were studied using 24 laboratory-scale units of vertical-flow constructed wetlands fed with faecal sludge supernatant. Plants collected from the surrounding wetlands were subjected to four salinity levels with electrical conductivity of 2, 3, 6 and 9 dS.m^-1 under both drained and flooded conditions for a 100 day period. The results revealed that salinity and flooding combined with salinity stresses had similar effect on plant survival, height and density, leading to growth and biomass reduction at the higher salinity level than under natural growth conditions. Despite these stress effects, E. pyramidalis remained healthy with no signs of salt or saline-flooding stress injury but higher biomass production. As E. pyramidalis is a forage plant its high biomass production in the wetland treatment systems shows the potential of wetland systems to create a local economy based on forage production and thus the opportunity to link sanitation stewardship to food production. This may contribute to sustain sanitation infrastructures at the same time as increasing food security, especially in developing countries.

Key words: Constructed wetlands, Echinochloa pyramidalis, faecal sludge, flooding, growth, salinity, yield potential.

African Journal of Environmental and Waste Management ISSN 2375-1266 Vol. 6 (5), pp. 001-019, May, 2019. © International Scholars Journals

Full Length Research Paper

Analysis of the measured medical waste generation rate in Tanzanian district hospitals using statistical methods

I. S. Kagonji and S. V. Manyele*

Department of Chemical and Mining Engineering, College of Engineering and Technology,

University of Dar es Salaam, P.O. Box 35131, Dar es Salaam Tanzania.

Accepted 16 January, 2019

Abstract

In this study the medical waste generation rates at Amana and Ligula hospitals were measured and analyzed. The rate of medical waste generation is high; about 2,250 kg/day in Amana and 2,500 kg/day in Ligula hospital. The waste generation rate per patient per day is also high about 1.8 (Amana) and 2.0 (Ligula) kg/patient.day. The daily medical waste generation rate is not constant, and fluctuates randomly. About 6 to 10% of waste generated is left uncollected. Eight medical waste categories were measured and compared: general waste, pathological waste, radioactive waste, chemical waste, infectious waste, sharps waste, pharmaceutical waste, and pressurized containers. The results indicated general waste to have high generation rate while others waste types such as chemical and radioactive wastes have low generation rates. Due to differences in generation rates, the data was normalized in order to compare statistical parameters used to assess medical waste generation rates. The statistical parameters used include: range, skewness, kurtosis, probability density functions and histograms. The study revealed that management of medical waste is still facing critical problems and requires skilled health workers, appropriate technologies and suitable equipment for collection, storage and transportation. The study will enable hospitals to understand trends in variations of medical waste generation and accommodate fluctuations in their plans and budgets.

Key words: Measured medical waste in selected Tanzania district hospitals, variations of waste generation, average waste generation, waste collection efficiency; range of waste generation, normalized waste generation.

African Journal of Environmental and Waste Management ISSN 2375-1266 Vol. 6 (5), pp. 001-012, May, 2019. © International Scholars Journals

Full Length Research Paper

Geoelectrical investigation and hydrochemical analysis of groundwater in a waste dump environment, Isolo, Lagos

Alile O. M.¹*, Ojuh D. O.², Iyoha A.³ and Egereonu J. C.⁴

^{1, 4}Department of Physics, Covenant University, Ota, Nigeria.

²Department of Basic Science, Benson Idahosa University, Benin, Nigeria.

³Department of Physics, Ambrose Alli University, Ekpoma, Nigeria.

Accepted 14 March, 2019

Abstract

Geoelectrical and hydrochemical analysis of groundwater in a waste dump environment was carried out to investigate the effect of the infiltrations of leachates and other sources of pollution from waste dump on groundwater. This was done by engaging the vertical electrical sounding method and laboratory water sample analysis. An Abem SAS 3000 terrameter was used to acquire the geophysical data from the vicinity of a major dumpsite called Oke Afa refuse dumpsite at Isolo, Lagos. The WINRESIST (version1.0) software was adopted in the interpretation of the survey data. Groundwater samples from boreholes were collected from the vicinity of the dumpsite with the aim of assessing the physiochemical impacts of the waste dumps on the quality of groundwater. Levels of various physiochemical parameters investigated include total dissolved solids (TDS), alkalinity, pH, electrical conductivity (EC), and hardness using standard analytical methods. Traces of metals like Fe, Cu, Zn, Mg and Na were equally determined using flame atomic absorption spectrophotometer (Unicam model 911). Many of the parameters determined following the specification of the World Health Organisation (WHO), groundwater samples in the area were found to be inadmissible for human consumption. This raises the question of toxicities of these elements, hence it is a threat to man. This shows that the groundwater is polluted because of the high conductivity of the water samples. This was confirmed by the water analysis from the study area in the laboratory.

Key words: Geoelectrical investigation, hydrochemical analysis, major dumpsite, groundwater.

African Journal of Environmental and Waste Management ISSN 2375-1266 Vol. 6 (5), pp. 001-012, May, 2019. © International Scholars Journals

Full Length Research Paper

Characterization and analysis of medical solid waste in Osun State, Nigeria

O. O. Fadipe¹, K. T. Oladepo²*, J. O. Jeje² and M. O. Ogedengbe²

¹Department of Civil Engineering, Osun State College of Technology, Esa-Oke, Osun State, Nigeria.

²Department of Civil Engineering, Obafemi Awolowo University, Ile-Ife, Osun State, Nigeria.

Accepted 10 January, 2019

Abstract

This paper reports the study of quantum and characterization of medical solid wastes generated by healthcare facilities in Osun State. The work involved administration of a questionnaire and detailed studies conducted on facilities selected on the basis of a combination of purposive and random sampling methods. The results show that the facilities are well spread among the 30 Local Government Areas; that the total quantity of medical waste generated in the state is 2672 kg/day and when domestic wastes are included the total is 5832 kg/day; that the medical wastes are not being properly disposed of as pathology wastes such as unclaimed dead bodies, placentas, umbilical cords are being dumped into unlined pits and other wastes in open dumps. A centralised system is proposed state–wide involving use of incinerators, landfills, aerobic lagoons, and reed beds. The Federal Ministry of Environment has responsibility to push for development of legislation and codes of practice that would guide facilities to achieve waste segregation, packaging in colour-coded and labeled bags, safe transportation and disposal of medical waste.

Key words: Medical solid wastes, pathological wastes, incinerators, landfills, aerobic lagoons, reed beds.

African Journal of Environmental and Waste Management ISSN 2375-1266 Vol. 6 (5), pp. 001-006, May, 2019. © International Scholars Journals

Full Length Research Paper

Reuse of wastewater in urban farming and urban planning implications in Katsina metropolis, Nigeria

Mohammed Murtala Ruma* and Abdullahi Usman Sheikh

*Department of Geography, Umaru Musa Yar’adua University, P. M. B. 2218 Katsina, Katsina State, Nigeria.

Accepted 18 January, 2019

Abstract

Studies on urban farming in Sub-Saharan African cities reveal the existence of literatures in Eastern, Southern and Central African cities. A few have focused on West Africa. In Nigeria, there is a paucity of information on reuse of waste water in urban farming. The purpose of this paper is to examine the status of wastewater reuse in urban farming in Katsina, an important urban area in the semi arid region of Nigeria. A total of 120 households were selected and interviewed out of the total number of 250 that officially registered with the Katsina Urban Planning Authority. It was found out that the reuse of wastewater in urban farming in the area is an occupation that is not only practiced as a fulltime and sole income earner for many households, but an activity that the town cannot do without. Being a city located within a semi-arid setting, relying on rainfed for successful promotion of urban farming is certainly a risky enterprise and hence the practice virtually has no substitute. Unfortunately urban planning process has not officially recognised and given attention to this important activity in the town. Appropriate recommendation on how to promote the activity and get it integrated into planning processes in the area have been given.

Key word: Urban, peri-urban, agriculture, farming, semi-arid, Nigeria.