Technology selection of biogas digesters for OFMSW via multi-criteria decision analysis

Multi-criteria decision analysis (MCDA) techniques are becoming increasingly popular in decision making for technology selection because of their ability to capture the multi-dimensionality of technologies. Biogas typically refers to an odourless gas produced by anaerobic digestion of biomass using microorganisms. Its production can occur naturally in marshes and landfills or more commonly, in specifically designed plants called biogas digesters under controlled conditions. For techno-economic efficiency of a biodigester, several factors such as cost of plant are taken into consideration. This paper examines various available technologies for biogas digesters using defined selection criteria via MCDA and chooses the best alternatives at various scales of biogas production for a case study in South Africa with municipal biowaste as the target feedstock. 14 biogas plants were analysed in this study and the Puxin and Bio4gas digesters were the best alternatives for small and large scale biogas production respectively

Technology selection and siting of a biogas plant for OFMSW via multi-criteria decision analysis

Abstract: Multi-criteria decision analysis (MCDA) techniques were applied to choose a biogas digester technology and a site from a list of potential alternatives for an anaerobic digestion (AD) system utilising the organic fraction of municipal solid waste (OFMSW) based on a case study at the University of Johannesburg’s Doornfontein campus in South Africa. The simple multi-attribute rating technique (SMART) and analytic hierarchy process (AHP) techniques of MCDA were used to select a suitable biodigester model and site respectively. From a list of 14 biodigester technologies to be established at 1 of 3 potential sites in the study area, the most preferred model was the Puxin digester to be sited near the Aurum ladies’ residence within the school campus to supply biogas for heating purposes

Sizing of an anaerobic biodigester for the organic fraction of municipal solid waste

The anaerobic digestion (AD) of the organic fraction of municipal solid waste (OFMSW) for biogas production is a potential solution to the growing challenges associated with municipal solid waste (MSW) management while simultaneously providing an alternative clean energy source. Biogas is produced by the anaerobic digestion (AD) of biomass using microorganisms in specifically designed plants called biogas digesters under controlled conditions or naturally in marshes and landfills. It is a rather clean and versatile fuel as opposed to fossil fuels. To design an efficient AD system, a proper understanding of the quality and quantity of available feedstock must be made as well as prevailing operating conditions. This paper represents steps that were taken to come up with an optimal size of biodigester to treat OFMSW produced at the University of Johannesburg’s Doornfontein Campus in downtown Johannesburg. The campus generates 232.2kg of OFMSW per day which required 30m3 of biodigester capacity

Alcohol use in fishing communities and men's willingness to participate in an alcohol, violence and HIV risk reduction intervention: qualitative findings from Rakai, Uganda.

Alcohol use, intimate partner violence (IPV) and HIV infection are associated, but few programmes and interventions have addressed their synergistic relationship or been evaluated for effectiveness and acceptability. This is a critical gap in populations with high rates of alcohol use, HIV and IPV, such as Uganda's fishing communities. This study examined drinking norms, barriers and facilitators to engagement in a risk reduction programme, and ideas for tailoring. Results showed that alcohol use is common in fishing villages. While men and women drink, gendered notions of femininity deem alcohol largely unacceptable for women. Plastic sachets of liquor were the most common alcoholic drink. Participants did not understand the definition of 'hazardous drinking', but recognised connections between drinking, violence and sexual risk-taking. The idea of an alcohol, IPV and HIV risk reduction intervention was supported, but barriers need to be addressed, including how best to help those uninterested in reducing their drinking, addressing normalisation of drinking and how best to inform those who truly need intervention. Intervention to people living with HIV around the time of diagnosis and treatment may be warranted. Study findings highlight the potential to integrate alcohol and IPV reduction programmes into an HIV service provision

Bio-methane potential of the organic fraction of municipal solid waste

Biogas is a gas formed from the breakdown of biomass by microorganisms in an anaerobic environment composed of methane (50%–70%) and carbon dioxide (30%–50%). The upgrading of biogas by the removal of carbon dioxide to increase the percentage of methane to over 92% produces bio-methane which is a potent versatile clean fuel. This paper represents a study that was carried out at the University of Johannesburg’s Doornfontein Campus (UJ DFC) to ascertain the potential of bio-methane recovery from the organic fraction of municipal solid waste (OFMSW) collected at the campus’ cafeteria and student residences. ..

The long-term effects of a family based economic empowerment intervention (Suubi+Adherence) on suppression of HIV viral loads among adolescents living with HIV in southern Uganda: Findings from 5-year cluster randomized trial

BACKGROUND: The rapid scale-up of HIV therapy across Africa has failed to adequately engage adolescents living with HIV (ALWHIV). Retention and viral suppression for this group (ALWHIV) is 50% lower than for adults. Indeed, on the African continent, HIV remains the single leading cause of mortality among adolescents. Strategies tailored to the unqiue developmental and social vulnerabilities of this group are urgently needed to enhance successful treatment. METHODS: We carried out a five-year longitudinal cluster randomized trial (ClinicalTrials.gov ID: NCT01790373) with adolescents living with HIV (ALWHIV) ages 10 to 16 years clustered at health care clinics to test the effect of a family economic empowerment (EE) intervention on viral suppression in five districuts in Uganda. In total, 39 accredited health care clinics from study districts with existing procedures tailored to adolescent adherence were eligible to participate in the trial. We used data from 288 youth with detectable HIV viral loads (VL) at baseline (158 -intervention group from 20 clinics, 130 -non-intervention group from 19 clinics). The primary end point was undetectable plasma HIV RNA levels, defined as \u3c 40 copies/ml. We used Kaplan-Meier (KM) analysis and Cox proportional hazard models to estimate intervention effects. FINDINGS: The Kaplan-Meier (KM) analysis indicated that an incidence of undetectable VL (0.254) was significantly higher in the intervention condition compared to 0.173 (in non-intervention arm) translated into incidence rate ratio of 1.468 (CI: 1.064-2.038), p = 0.008. Cox regression results showed that along with the family-based EE intervention (adj. HR = 1.446, CI: 1.073-1.949, p = 0.015), higher number of medications per day had significant positive effects on the viral suppression (adj.HR = 1.852, CI: 1.275-2.690, p = 0.001). INTERPRETATION: A family economic empowerment intervention improved treatment success for ALWHIV in Uganda. Analyses of cost effectiveness and scalability are needed to advance incorporation of this intervention into routine practice in low and middle-income countries

"The Bottle Is My Wife": Exploring Reasons Why Men Drink Alcohol in Ugandan Fishing Communities.

Fishing communities in Uganda have high rates of excessive alcohol consumption and negative health outcomes related to alcohol consumption, such as HIV acquisition and transmission and intimate partner violence victimization and perpetration. Research lacks understanding of alcohol use in Ugandan fishing communities, underlying reasons for excessive drinking among fishermen or how their community perceives negative health outcomes linked to excessive alcohol consumption. This qualitative study was conducted among Ugandan fisherfolk to determine why excessive alcohol consumption has overtaken their communities. Through analyzing in-depth interviews and focus group discussions, reasons for drinking and community perceptions of drinking were explored using the Socio Ecological Model and the Time Perspective Theory. Interviews were coded into two content themes: social influences on drinking and using alcohol to cope with stress. Participants acknowledged links between excessive alcohol consumption and negative health outcomes within their families and communities. These findings highlight the need for alcohol-related reduction interventions that are sensitive to contextual factors and self-identified contributors to problematic alcohol use within individuals and their communities. Such interventions must consider the social, ecological and economic conditions within fishing sites, focusing not only on individual-level behavioral change but also challenging the underlying structures that foster excessive alcohol consumption

Process evaluation of the SHARE intervention for preventing intimate partner violence and HIV infection in Rakai, Uganda.

The Safe Homes And Respect for Everyone (SHARE) intervention introduced an intimate partner violence (IPV) prevention approach into Rakai Health Sciences Program, an established HIV research and service organization in Uganda. A trial found exposure to SHARE was associated with reductions in IPV and HIV incidence. This mixed methods process evaluation was conducted between August 2007 and December 2009, with people living in SHARE intervention clusters, to assess awareness about/participation in SHARE, motivators and barriers to involvement, and perceptions of how SHARE contributed to behavior change. Surveys were conducted with 1407 Rakai Community Cohort Study participants. Qualitative interviews were conducted with 20 key informants. Most (77%) were aware of SHARE, among whom 73% participated in intervention activities. Two-thirds of those who participated in SHARE felt it influenced behavior change related to IPV. While some felt confident to take part in new IPV-focused activities of a well-established program, others were suspicious of SHARE's motivations, implying awareness raising is critical. Many activities appealed to the majority (e.g., community drama) while interest in some activities was limited to men (e.g., film shows), suggesting multiple intervention components is ideal for wide-reaching programming. The SHARE model offers a promising, acceptable approach for integrating IPV prevention into HIV and other established health programs in sub-Saharan Africa

Cost effectiveness analysis of clinically driven versus routine laboratory monitoring of antiretroviral therapy in Uganda and Zimbabwe.

BACKGROUND: Despite funding constraints for treatment programmes in Africa, the costs and economic consequences of routine laboratory monitoring for efficacy and toxicity of antiretroviral therapy (ART) have rarely been evaluated. METHODS: Cost-effectiveness analysis was conducted in the DART trial (ISRCTN13968779). Adults in Uganda/Zimbabwe starting ART were randomised to clinically-driven monitoring (CDM) or laboratory and clinical monitoring (LCM); individual patient data on healthcare resource utilisation and outcomes were valued with primary economic costs and utilities. Total costs of first/second-line ART, routine 12-weekly CD4 and biochemistry/haematology tests, additional diagnostic investigations, clinic visits, concomitant medications and hospitalisations were considered from the public healthcare sector perspective. A Markov model was used to extrapolate costs and benefits 20 years beyond the trial. RESULTS: 3316 (1660LCM;1656CDM) symptomatic, immunosuppressed ART-naive adults (median (IQR) age 37 (32,42); CD4 86 (31,139) cells/mm(3)) were followed for median 4.9 years. LCM had a mean 0.112 year (41 days) survival benefit at an additional mean cost of $765 [95$7386 [3277,dominated] per life-year gained and $7793 [4442,39179] per quality-adjusted life year gained. Routine toxicity tests were prominent cost-drivers and had no benefit. With 12-weekly CD4 monitoring from year 2 on ART, low-cost second-line ART, but without toxicity monitoring, CD4 test costs need to fall below$3.78 to become cost-effective (<3xper-capita GDP, following WHO benchmarks). CD4 monitoring at current costs as undertaken in DART was not cost-effective in the long-term. CONCLUSIONS: There is no rationale for routine toxicity monitoring, which did not affect outcomes and was costly. Even though beneficial, there is little justification for routine 12-weekly CD4 monitoring of ART at current test costs in low-income African countries. CD4 monitoring, restricted to the second year on ART onwards, could be cost-effective with lower cost second-line therapy and development of a cheaper, ideally point-of-care, CD4 test