scholarly journals Faecal sludge as a solid industrial fuel: a pilot-scale study

2017 ◽  
Vol 7 (2) ◽  
pp. 243-251 ◽  
Author(s):  
Moritz Gold ◽  
Daniel Isaac Waya Ddiba ◽  
Alsane Seck ◽  
Patrick Sekigongo ◽  
Alassane Diene ◽  
...  
Keyword(s):  
Calorific Value ◽  
Pilot Scale ◽  
Wastewater Sludge ◽  
Sub Saharan Africa ◽  
Clay Bricks ◽  
Financial Benefits ◽  
Treatment Technologies ◽  
Sub Saharan ◽  
Faecal Sludge

Revenues from faecal sludge (FS) treatment end products could offset treatment costs and contribute to financially viable sanitation. In urban sub-Saharan Africa, energy-producing resource recovery has the potential to generate greater revenue than use as soil conditioner. In contrast with wastewater sludge, the technical feasibility of using dried FS as solid fuel in industries has not been investigated. This study evaluated it through characterization of dried FS from drying beds and by assessing the combustion performance in two pilot-scale kilns, in Kampala and Dakar. Results from the fuel characterization demonstrate that dried FS had comparable fuel characteristics as wastewater sludge considering calorific value and ash content. The calorific values and ash contents were 10.9–13.4 MJ/kg dry matter (DM) and 47.0–58.7%, respectively. Results from pilot-scale experiments suggest that dried FS can be effective in providing energy for industries. Temperatures in pilot-scale kilns fueled by FS were 800 °C, sufficient for curing of clay bricks, and 437 °C, sufficient for waste oil regeneration. In Kampala and Dakar, an estimated 20,000 tons of FS DM per year accumulate. Tapping the industrial fuel market and financial benefits could be realized through optimization of onsite sanitation and treatment technologies.

scholarly journals To char or not to char? Review of technologies to produce solid fuels for resource recovery from faecal sludge

2019 ◽  
Vol 9 (2) ◽  
pp. 210-224 ◽  
Author(s):  
Nienke Andriessen ◽  
Barbara J. Ward ◽  
Linda Strande
Keyword(s):  
Solid Fuel ◽  
Calorific Value ◽  
Resource Recovery ◽  
Hydrothermal Carbonization ◽  
Pilot Scale ◽  
Market Potential ◽  
Sub Saharan Africa ◽  
Combustion Technology ◽  
Sub Saharan ◽  
Faecal Sludge

Abstract Resource recovery from faecal sludge can take many forms, including as a fuel, soil amendment, building material, protein, animal fodder, and water for irrigation. Resource recovery as a solid fuel has been found to have high market potential in Sub-Saharan Africa. Laboratory- and pilot-scale research on faecal sludge solid fuel production exists, but it is unclear which technology option is most suitable in which conditions. This review offers an overview and critical analysis of the current state of technologies that can produce a dried or carbonized solid fuel, including drying, pelletizing, hydrothermal carbonization, and slow-pyrolysis. Carbonization alters fuel properties, and in faecal sludge, it concentrates the ash content and decreases the calorific value. Overall, a non-carbonized faecal sludge fuel is recommended, unless a carbonized product is specifically required by the combustion technology or end user. Carbonized and non-carbonized fuels have distinct characteristics, and deciding whether to char or not to char is a key judgement in determining the optimal solid fuel technology option. Based on the existing evidence, this review provides a decision-making structure for selecting the optimal technology to produce a faecal sludge solid fuel and identifies the top research needs prior to full-scale implementation.

Chemical Constituents and Antibacterial Activity of Cissus Aralioides.

2020 ◽  
Vol 17 ◽  
Author(s):  
Balogun Olaoye Solomon ◽  
Ajayi Olukayode Solomon ◽  
Owolabi Temitayo Abidemi ◽  
Oladimeji Abdulkarbir Oladele ◽  
Liu Zhiqiang
Keyword(s):  
Plant Extract ◽  
Chemical Constituents ◽  
Ethyl Acetate Fraction ◽  
Antibacterial Activities ◽  
Sub Saharan Africa ◽  
Chromatographic Purification ◽  
Whole Plant ◽  
Sub Saharan ◽  
First Time

: Cissus aralioides is a medicinal plant used in sub-Saharan Africa for treatment of infectious diseases; however the chemical constituents of the plant have not been investigated. Thus, in this study, attempt was made at identifying predominant phytochemical constituents of the plant through chromatographic purification and silylation of the plant extract, and subsequent characterization using spectroscopic and GC-MS techniques. The minimum inhibitory concentration (MICs) for the antibacterial activities of the plant extract, chromatographic fractions and isolated compounds were also examined. Chromatographic purification of the ethyl acetate fraction from the whole plant afforded three compounds: β-sitosterol (1), stigmasterol (2) and friedelin (3). The phytosterols (1 and 2) were obtained together as a mixture. The GC-MS analysis of silylated extract indicated alcohols, fatty acids and sugars as predominant classes, with composition of 24.62, 36.90 and 26.52% respectively. Results of MICs indicated that friedelin and other chromatographic fractions had values (0.0626-1.0 mg/mL) comparable with the standard antibiotics used. Characterization of natural products from C. aralioides is being reported for the first time in this study.

Water treatment and supply: intermediate education in Sub-Saharan Africa

2011 ◽  
Vol 11 (5) ◽  
pp. 578-585 ◽  
Author(s):  
P. Byars ◽  
B. Antizar-Ladislao
Keyword(s):  
International Development ◽  
Current Approach ◽  
Appropriate Technology ◽  
Sub Saharan Africa ◽  
Experimental Learning ◽  
Treatment Technologies ◽  
Technical Expert ◽  
Sub Saharan ◽  
Water Supply And Treatment ◽  
Water Provision

In 1973 the economist E.F Schumacher wrote ‘Small is Beautiful’. In this he created the vision of a concept known as ‘intermediate technology’. Directly from this grew the popular ‘appropriate technology’ movement. An appropriate technology, in the ideal sense, is designed with special consideration of the environmental, ethical, cultural, social, political, and economical aspects of the community it is intended for. The term ‘appropriate technology’ is continually used when referring to water supply and treatment technologies in international development. The widespread provision of hand-pumps in Africa by Non-Governmental Organisations (NGOs) fully characterises the approach and remains the most prominent display of technologies, transferred on a charitable basis, between the developed and developing countries. However, after years of NGOs working with hand-pumps in Africa the first signs are showing that there are widespread problems with the current approach. In many cases the nature of ‘appropriateness’ is determined from the perspective of an external technical expert and not by the communities themselves. The lack of appropriateness is leading to severely unsustainable projects. This paper explores the linkage that has not been clearly mapped in technology transfer, i.e., the use of scientific and technical education. The focus of the transfer is on developing the knowledge and skills necessary to evaluate ‘appropriateness’ from the perspective of the end user. It explores the concept of ‘Intermediate Education’ – a method of using experimental learning to address a systemic weakness in safe water provision in development.

scholarly journals Inhibition of Ammonia and Hydrogen Sulphide Using Plant Waste Materials for Faecal Sludge Odour Control in Dry Sanitation Toilet Facilities

2021 ◽  
Author(s):  
Bernice Mawumenyo Senanu ◽  
Patrick Boakye ◽  
Sampson Oduro-Kwarteng ◽  
Divine Damertey Sewu ◽  
Esi Awuah ◽  
...  
Keyword(s):  
Rice Husk ◽  
Hydrogen Sulphide ◽  
Cost Effective ◽  
Sub Saharan Africa ◽  
Open Defecation ◽  
Sub Saharan ◽  
Sanitation Systems ◽  
S Peak ◽  
Faecal Sludge ◽  
Peak Value

Abstract On-site dry sanitation facilities, although cheaper than wet sanitation systems, suffer from high malodour and insect nuisance as well as poor aesthetics. The high odour deters users from utilizing dry sanitation toilet as an improved facility leading to over 20% open defecation in Sub-Saharan Africa. To address this malodour concern, this study first assessed odour levels, using hydrogen sulphide (H2S) and ammonia (NH3) as indicators, on two (2) dry sanitation facilities (T1 and T2). The potential of using biomass (sawdust, rice husk, moringa leaves, neem seeds), ash (coconut husk, cocoa husk) or biochar (sawdust, rice husk, bamboo) as biocovers to remove or suppress odour from fresh faecal sludge (FS) over a 12-day period was investigated. Results showed high odour levels, beyond and below the threshold limit for unpleasantness for humans on H2S (peak value: T1 = 3.17 ppm; T2 = 0.22 ppm > 0.05 ppm limit) and NH3 (peak value: T1 = 6.88 ppm; T2 = 3.16 ppm < 30 ppm limit), respectively. The biomasses exhibited low pH (acidic = 5-7) whereas the biochars and ashes had higher pHs (basic = 8-13). Acidic biocovers generally reduced NH3 emission significantly (12.5% to 64.8%) whereas basic biocovers were more effective at H2S emission reduction (80.9% to 96.2%). In terms of H2S and NH3 removal, sawdust biochar was the most effective biocover with odour abatement values of 96.2% and 74.7%, respectively. The results suggest that locally available waste plant-based materials, like sawdust, when converted to biochar can serve as a cost-effective and sustainable way to effectively combat odour-related issues associated with dry sanitation facilities to help stop open defecation.

scholarly journals The Orphan Crop Crassocephalum crepidioides Accumulates the Pyrrolizidine Alkaloid Jacobine in Response to Nitrogen Starvation

2021 ◽  
Vol 12 ◽  
Author(s):  
Sebastian Schramm ◽  
Wilfried Rozhon ◽  
Adebimpe N. Adedeji-Badmus ◽  
Yuanyuan Liang ◽  
Shahran Nayem ◽  
...  
Keyword(s):  
Pyrrolizidine Alkaloid ◽  
Sub Saharan Africa ◽  
Close Relative ◽  
Environmental Cues ◽  
N Deficiency ◽  
Sub Saharan ◽  
Rate Limiting ◽  
Homospermidine Synthase ◽  
Orphan Crop

Crassocephalum crepidioides is an African orphan crop that is used as a leafy vegetable and medicinal plant. Although it is of high regional importance in Sub-Saharan Africa, the plant is still mainly collected from the wild and therefore efforts are made to promote its domestication. However, in addition to beneficial properties, there was first evidence that C. crepidioides can accumulate the highly toxic pyrrolizidine alkaloid (PA) jacobine and here it was investigated, how jacobine production is controlled. Using ecotypes from Africa and Asia that were characterized in terms of their PA profiles, it is shown that the tetraploid C. crepidioides forms jacobine, an ability that its diploid close relative Crassocephalum rubens appears to lack. Evidence is provided that nitrogen (N) deficiency strongly increases jacobine in the leaves of C. crepidioides, that this capacity depends more strongly on the shoot than the root system, and that homospermidine synthase (HSS) activity is not rate-limiting for this reaction. A characterization of HSS gene representation and transcription showed that C. crepidioides and C. rubens possess two functional versions, one of which is conserved, that the HSS transcript is mainly present in roots and that its abundance is not controlled by N deficiency. In summary, this work improves our understanding of how environmental cues impact PA biosynthesis in plants and provides a basis for the development of PA-free C. crepidioides cultivars, which will aid its domestication and safe use.

scholarly journals Pteropine Orthoreovirus in an Angolan Soft-Furred Fruit Bat (Lissonycteris angolensis) in Uganda Dramatically Expands the Global Distribution of an Emerging Bat-Borne Respiratory Virus

Viruses ◽  
2020 ◽  
Vol 12 (7) ◽  
pp. 740
Author(s):  
Andrew J. Bennett ◽  
Tony L. Goldberg
Keyword(s):  
Southeast Asia ◽  
Respiratory Virus ◽  
Rectal Swab ◽  
Geographic Distance ◽  
Sub Saharan Africa ◽  
Zoonotic Virus ◽  
Fruit Bat ◽  
Dsrna Genome ◽  
Sub Saharan

Pteropine orthoreovirus (PRV; Reoviridae: Spinareovirinae) is an emerging bat-borne zoonotic virus that causes influenza-like illness (ILI). PRV has thus far been found only in Australia and Asia, where diverse old-world fruit bats (Pteropodidae) serve as hosts. In this study, we report the discovery of PRV in Africa, in an Angolan soft-furred fruit bat (Lissonycteris angolensis ruwenzorii) from Bundibugyo District, Uganda. Metagenomic characterization of a rectal swab yielded 10 dsRNA genome segments, revealing this virus to cluster within the known diversity of PRV variants detected in bats and humans in Southeast Asia. Phylogeographic analyses revealed a correlation between geographic distance and genetic divergence of PRVs globally, which suggests a geographic continuum of PRV diversity spanning Southeast Asia to sub-Saharan Africa. The discovery of PRV in an African bat dramatically expands the geographic range of this zoonotic virus and warrants further surveillance for PRVs outside of Southeast Asia.

scholarly journals Genetic dissection of drug resistance in trypanosomes

Parasitology ◽  
2013 ◽  
Vol 140 (12) ◽  
pp. 1478-1491 ◽  
Author(s):  
SAM ALSFORD ◽  
JOHN M. KELLY ◽  
NICOLA BAKER ◽  
DAVID HORN
Keyword(s):  
Neglected Tropical Diseases ◽  
Sub Saharan Africa ◽  
Genetic Dissection ◽  
Molecular Tools ◽  
Sequencing Technology ◽  
Exponential Increase ◽  
Technological Developments ◽  
Sub Saharan ◽  
Identification And Characterization

SUMMARYThe trypanosomes cause two neglected tropical diseases, Chagas disease in the Americas and African trypanosomiasis in sub-Saharan Africa. Over recent years a raft of molecular tools have been developed enabling the genetic dissection of many aspects of trypanosome biology, including the mechanisms underlying resistance to some of the current clinical and veterinary drugs. This has led to the identification and characterization of key resistance determinants, including transporters for the anti-Trypanosoma bruceidrugs, melarsoprol, pentamidine and eflornithine, and the activator of nifurtimox-benznidazole, the anti-Trypanosoma cruzidrugs. More recently, advances in sequencing technology, combined with the development of RNA interference libraries in the clinically relevant bloodstream form ofT. bruceihave led to an exponential increase in the number of proteins known to interact either directly or indirectly with the anti-trypanosomal drugs. In this review, we discuss these findings and the technological developments that are set to further revolutionise our understanding of drug-trypanosome interactions. The new knowledge gained should inform the development of novel interventions against the devastating diseases caused by these parasites.

The characterization of Brucella strains isolated from cattle in Algeria reveals the existence of a B. abortus lineage distinct from European and Sub-Saharan Africa strains

2017 ◽  
Vol 211 ◽  
pp. 124-128 ◽  
Author(s):  
Mammar Khames ◽  
Virginie Mick ◽  
M. Jesús de Miguel ◽  
Guillaume Girault ◽  
Raquel Conde-Álvarez ◽  
...  
Keyword(s):  
Sub Saharan Africa ◽  
Sub Saharan

scholarly journals Characterization of virulence factors of Salmonella isolated from human stools and street food in urban areas of Burkina Faso

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Marguerite E. M. Nikiema ◽  
Solange Kakou-ngazoa ◽  
Absatou Ky/Ba ◽  
Aboubacar Sylla ◽  
Evariste Bako ◽  
...  
Keyword(s):  
Burkina Faso ◽  
Urban Areas ◽  
Virulence Genes ◽  
Sub Saharan Africa ◽  
Clinical Isolates ◽  
Genetic Profile ◽  
Street Food ◽  
Serological Identification ◽  
Sub Saharan

Abstract Background This study was undertaken to identify and functionally characterize virulence genes from Salmonella isolates in street food and stool cultures. From February 2017 to May 2018, clinical and food Salmonella strains were isolated in three regions in Burkina Faso. Salmonella was serotyped according to the White-Kauffmann-Le Minor method, and polymerase chain reaction (PCR) was used to detec invA, spvR, spvC, fimA and stn virulence genes commonly associated with salmonellosis in Sub-Saharan Africa. Results A total of 106 Salmonella isolates (77 human stools; 14 sandwiches) was analyzed using a serological identification with an O-group test reagent. The presence of Salmonella was confirmed in 86% (91/106) of the samples were reactive (OMA-positive/OMB-positive). Salmonella serogroup O:4,5 was the most common serogroup detected (40%; 36/91). Salmonella Enteritidis and Typhimurium represented 5.5% (5/91) and 3.3% (3/91), respectively and were identified only from clinical isolates. Furthermore, 14 serotypes of Salmonella (12/91 human strains and 2/15 sandwich strains) were evocative of Kentucky/Bargny serotype. For the genetic profile, 66% (70/106) of the Salmonella had invA and stn genes; 77.4% (82/106) had the fimA gene. The spvR gene was found in 36.8% (39/106) of the isolates while 48.1% (51/106) had the spvC gene. Among the identified Salmonella Enteritidis and Salmonella Typhimurium isolated from stools, the virulence genes detected were invA (3/5) versus (2/3), fimA (4/5) versus (3/3), stn (3/5) versus (2/3), spvR (4/5) versus (2/3) and spvC (3/5) versus (2/3), respectively. Conclusion This study reports the prevalence of Salmonella serotypes and virulence genes in clinical isolates and in street foods. It shows that food could be a significant source of Salmonella transmission to humans. Our results could help decision-making by the Burkina Faso health authority in the fight against street food-related diseases, in particular by training restaurateurs in food hygiene.

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