Search

Hospital waste is a special category of waste that is quite detrimental as it may contain infectious and contaminated substances thus posing serious threats to the environment and public health. The knowledge of quantities and characteristics of hospital waste, helps in proper management. This study aimed at waste quantification, characterization, and assessment of the general waste management patterns at Mulago referral hospital, Uganda. The experiment was carried out for 30 consecutive days and solid waste generated within 24 hours were collected from different departments of the Mulago hospital in designated containers, sorted and weighed then grouped into general waste and clinical waste. The study established that general waste comprises 72% while clinical waste is 28% of the total waste generated in the facility. The average solid waste generation rate was found to be at 111.4kg per day with wards producing the highest quantities, followed by operating theatres, kitchen, public areas, laundry, and administration. Using the individualized Rapid Assessment Tool (I-RAT), it was found that Mulago hospital's authorities are aware of policies surrounding the handling and disposal methods of waste and gaps were observed in compliance. The average solid waste sorting compliance in the hospital was found very low, 37.4%, with the highest compliance in operating theatres at 62.8%, followed by the administration 51.7%, kitchen 32%, wards 27.3%, public areas 25.6%, and laundry 25%. The analysis of the discharged liquid waste revealed that Lead, Nitrate, COD, and BOD concentrations were beyond the permissible limits. Therefore, we recommend commitment on compliance with policies and legislation measures to safeguard the workers and environment. Technically, we recommend a bio-chemical pre-treatment of wastewater for the abatement of the pollutants prior to discharging it into the environment. Also, to minimize waste mixing and spillage at the waste generation points as a result of inappropriate bins, we recommend a combined 0.062 m3 capacity containers for general waste and 0.024 m3 for clinical waste in all hospital units.

EIA is an important regulatory tool which can play a key role in achieving of Sustainable Development Goals (SDGs) and it is defined as a tool used to predict the likely impact of a project or development on the environment. This study aims to evaluate the effectiveness of Environmental Impact Assessment (EIA) in Rwanda. Data were collected using a descriptive survey design. A structured questionnaire was developed, pretested and administered to a sample of 110 respondents using purposive sampling technique. Of the 110 questionnaires administered 82 were retrieved and analyzed into frequencies and simple percentages using the Statistical Package for the Social Sciences (SPSS) and Microsoft Excel 2016 version. The study showed that 1188 EIA clearances were issued between 2011 and 2019 while 3085 EIA certificates were issued between 2006 and 2019. The survey revealed that EIA experts in Rwanda largely gain experience from the construction, water and sanitation, and agriculture sectors. Though the legislation covering EIA in Rwanda is very strong, the study showed that the only way to improve the effectiveness of EIA is to strengthen the quality of documentation and to offer electronic services as well as incorporating EIA results into decision‐making mechanisms. The study also identified insufficient monitoring of environmental management plans (45% of respondents), poor follow‐ups (30%), inexperienced practitioners in EIA implementation and auditing (30%), lack of professionalism by EIA practitioners (30%), and poor public participation (25%). This could potentially hinder EIA effectiveness. The study therefore recommends that quality documentation and electronic services as well as follow‐up to review projects be enforced to improve EIA effectiveness. [ABSTRACT FROM AUTHOR]

This study assessed the current status of solid waste management (SWM) in the City of Kigali (CoK), the capital city of Rwanda. This assessment was done using systems analysis methodology of “wasteaware” benchmark indicators for integrated sustainable waste management in cities. This method of assessing helps to assess the Municipal Solid Waste Management (MSWM) in a city according to its physical components and governance features. Data were collected during a 6-month period from May to October 2017, but verification took other four months (Up to February 2018). Data were obtained from official reports, legal documents, and interviews with key personnel and operators and also from official and unofficial dumpsites visits. In CoK, approximately 232,870 tons of MSW is generated per year, MSW collection and transportation is done by private companies but the only dumpsite present in Kigali is fully controlled by the City of Kigali. Residents pay waste collectors according to their social classes and their locations. There is no official recycling system; recycling activities are informally performed by private companies and some wastes, like plastic bottles, are taken to Uganda and Tanzania to be recycled. This study found that the recycling rate was 10% contrarily to the 2% which is recorded by official sources. This study has contributed by filling the gap in literature on waste management for the city of Kigali and it recommends that the Government represented by the CoK should do more in terms of investing in SWM and creating a relationship between private waste collectors and local communities, and the private sector should be mobilized to invest in SWM activities.

The study assessed the impact of volatile fatty acids (VFA) to total alkalinity (TA) ratio (VFA/TA), and percentage volatile solids (VS) reduction of batch and semi-continuous anaerobic co-digestion of palm nut paste waste (PNPW) and anaerobic-digested rumen waste (ADRW) on digester stability and biogas production under the environmental condition of 50 ± 1°C and hydraulic retention time of 21 days for the batch studies and 14 days for semi-continuous co-digestion. The co-digestion ratios were based on percentage digester volume corresponding to 90%:10%, 75%:25% and 50%:50%. During batch and semi-continuous anaerobic co-digestion, VFA/TA of 0.32–1.0 and VS reduction of 53–67% were observed as the stable range at which biogas production was maximum. In terms of semi-continuous anaerobic digestion (AD), except for the 50%:50% ratio where biogas production progressed steadily from the first to fourteenth days, biogas production initially dropped from 180.1 to 171.3 mL between the first and third days of the 90%:10% reaching a maximum of 184 mL on the fourteenth day. Biogas production declined from 198.8 to 187.5 mL on the second day and then increased to 198.8 ± 0.5 mL in the case of the 75%:25% with a significant difference between the treatment ratios at p < 0.05. Therefore, the study can confirm that the 50%:50% ratio (PNPW:ADRW) is a suitable option for managing crude fat-based waste under thermophilic AD due to its potential for rapid start-up and complete biodegradation of active biomass within a 21-day period. This presupposes that residual methane as greenhouse gas will be void in the effluent if disposed of. [ABSTRACT FROM AUTHOR]

Carbon monoxide (CO) is harmful to human health, yet there is limited evidence concerning emissions associated with biomass fuel cooking in occupational settings. Real-time 48-hour monitoring of CO concentrations at breathing height, was undertaken in staff and student kitchen and serving areas of two commercial canteens. We characterized two diurnal CO peaks coinciding with cooking activities. Peak CO concentrations of 255.5 ppm and 1-hour average of 76.3 ppm (IQR: 57.8–109.0 ppm) were observed in the student kitchen; the staff kitchen levels were 208.5 ppm, and 76.3 ppm (IQR: 52.5–114.0 ppm), respectively. High magnitude CO concentrations (8-hour average: 40.7 ppm SD: 40.0 ppm) which exceed World Health Organisation (WHO) Indoor Air Quality standards were observed. Further investigation of personal exposure and health impacts among kitchen staff is required, to inform interventions in this setting. [ABSTRACT FROM AUTHOR]

This paper reports the first research investigation in urban Rwanda of indoor PM2.5 and CO levels associated with biomass fuel cooking activities. The study included a survey of household and cooking activity among 40 biomass fuel households in Nyarugenge District, Kigali, together with air quality monitoring for particulate matter (PM) and carbon monoxide (CO) within those 20 households in which cooking was performed exclusively indoors. Pollutant concentrations were measured at one-minute intervals, using the IQ Air Visual Pro sensor (PM2.5) and electrochemical COA1 (CO) detector adapter devices, respectively. In the majority of households (90%, n = 18) in which monitoring was performed, mean pollutant concentrations were in excess of WHO Air Quality (WHO-AQ) Standards with 24-h values of 93 µgm3 and 35.1 ppm for PM2.5 and CO, respectively. Efforts are required to change household energy policies in favour of cleaner fuel sources and develop effective structural ventilation. [ABSTRACT FROM AUTHOR]

Abstract: In order to mitigate the adverse impacts of climate change, CO2 captured from carbon emitters like coal-fired power plants may be stored in deep saline aquifers. This action may cause pressure changes, which affect subsurface volumes. The main purpose of this study is to evaluate the pressure changes during CO2 sequestration in CO2 storage formation embedded in a sequence of aquifers and aquitard of Qianjiang depression area in China. In order to demonstrate the transient pressure, we have conducted TOUGH2 modeling of CO2 injection into closed formations of different thicknesses assuming impermeable boundaries. A 2-D radially symmetric model was developed to represent a CO2 storage site in the Qianjiang depression area. The storage formation into which CO2 was injected is 120 m thick and located at a depth of about 1380m below the ground surface. The CO2 injection thickness was 15m from the bottom of the storage formation. Carbon dioxide was injected into a zone of 77 m radial extent representing a few distributed wells. Injection occurs at an annual rate of 2.488 * 10 7 tonnes of CO2 representing 16 times the CO2 rate captured from a medium-size-coal-fired power plant. The simulation runs cover a time period of 100 years altogether, comprising the 30-year injection period and a 70-year post-injection period. The pressure buildup results after one year never attains 50% of initial pressure (maximum tolerable pressure buildup). Our simulation results indicate that interlayer pressure propagation through a sequence of aquitard/aquifer will not affect the top aquifer. Moderate pressure increases occur in top aquifer only in case when pore compressibility was reduced by one order of magnitude. [Copyright &y& Elsevier]