The "old-new" challenges of water, sanitation and bioremediation in developing countries

Developing countries face challenges in the development of infrastructure and population growth. These lead to “side-effects" such as uncontrolled urbanization and the fact that basic services such as water and sanitation are lagging behind the actual needs on the ground. Historical challenges, lack of skilled staff and often lack of sustained funding are some of the reasons for the status quo. Extent of water and sanitation coverage often forces national and local governments to install the minimum-standard solutions, e.g. the ventilated improved pit latrines. This improves the public health status in the short-term, but causes problem in the long run due to the lack of regular maintenance such as through lack emptying of pits. Sometimes, construction of these facilities is of inferior standard. Pits are often built without lining or zero consideration is given to the local conditions in terms of soil properties, water table and the number of toilet users

Anaerobic digestion of fungally pre-treated wine distillery wastewater

The combination of fungal pre-treatment with Trametes pubescens and anaerobic digestion were tested for the removal of chemical oxygen demand (COD) and phenolic compounds from wine distillery wastewater. The COD removal efficiency after fungal pre-treatment reached 53.3%. During digestion, pH buffering was achieved using CaCO3 and K2HPO4. This provided a stable environment inside digester for efficient and time-independent COD removal. The total COD removal efficiency reached 99.5%, and the system proved able to eliminate shock COD loads, as indicated by the concentrations of sludge and volatile fatty acids. Complex changes of phenolic compounds are suspected in anaerobic digestionsystem, and are investigated further

Bioremediation of trace organic compounds found in precious metals refineries wastewaters: A review of potential options

Platinum group metal (PGM) refining processes produce large quantities of wastewater, which is contaminated with the compounds that make up the solvents/extractants mixtures used in the process. These compounds often include solvesso, β-hydroxyxime, amines, amides and methyl isobutyl ketone. A process to clean up PGM refinery wastewaters so that they could be re-used in the refining process would greatly contribute to continual water storage problems and to cost reduction for the industry. Based on the concept that organic compounds that are produced biologically can be destroyed biologically, the use of biological processes for the treatment of organic compounds in other types of waste stream has been favoured in recent years, owing to their low cost and environmental acceptability. This review examines the available biotechnologies and their effectiveness for treating compounds likely to be contained in precious metal extraction process wastewaters. The processes examined include: biofilters, fluidized bed reactors, trickle-bed bioreactors, bioscrubbers, two-phase partitioning bioreactors, membrane bioreactors and activated sludge. Although all processes examined showed adequate to excellent removal of organic compounds from various gaseous and fewer liquid waste streams, there was a variation in their effectiveness. Variations in performance of laboratory-scale biological processes are probably due to the inherent change in the microbial population composition due to selection pressure, environmental conditions and the time allowed for adaptation to the organic compounds. However, if these factors are disregarded, it can be established that activated sludge and membrane bioreactors are the most promising processes for use in the treatment of PGM refinery wastewaters

Preliminary assessment of the gender aspects of disaster vulnerability and loss of human life in South Africa

South Africa has reached a medium level of human development and has a heterogeneous situation with respect to disaster risk management. In this article, a preliminary assessment of the gender aspects of disaster vulnerability and fatalities is presented. The United Nations, the Health Systems Trust and Statistics South Africa were used as data sources for the following gender-segregated values: the life expectancy at birth, unemployment rates, the human development index values, the maternal mortality rates and the number of deaths from unnatural and non-natural causes. The relevant inequality indices were then calculated and used to draw conclusions regarding the gender aspects of disaster risk management in South Africa. Results of the calculations indicate that between 1980 and 2011 men were 10% more vulnerable with respect to their health status. However, the gender differences have been decreasing in recent years. Access of women to healthcare is decreasing with time, potentially decreasing the recovery potential of whole families. Women are more economically vulnerable than men in South Africa, as they are 16.3% – 33% more likely to be unemployed than men. Educational status of both genders in South Africa is comparable based on literacy and enrolment rates at primary and secondary level. On the other hand, men are five times more likely to suffer fatal injuries during disasters

Mini-review on the use of liquid membranes in the extraction of platinum group metals from mining and metal refinery wastewaters/side-streams

The current mini-review focuses on the use of liquid membranes in the platinum group metal (PGM/PGMs) extraction from various types of wastewaters to prevent environmental pollution; and for the metal recovery to address the scarcity of the PGMs in the industrial cycles. The bulk liquid membranes have been used to the extracted PGMs from the (acidic) aqueous media with recoveries of up to 96.3 ± 2.5% of the original PGM amount. The extraction time generally ranges from 2 to 24 hours. The bulk membrane liquid in the PGM extraction will depend on the covalent structure of the extractant, the feed phase PGM concentration and the complex of the PGM in question that is actually extracted from the aqueous environment. The advantages of this type of liquid membrane include its operational simplicity, but the disadvantages include limited possibility to improve the extraction performance of the system. Literature data are encouraging as they indicate that extraction of PGMs from mining and metal-refinery side-streams does not suffer from interference from metal contaminants that are commonly found in the mining and metal refinery side-streams, e.g. iron. Thus further research should focus on the application of ELM to extraction of PGMs from said wastewaters and major research drive should focus on the use of the Taylorvortex column and the non-Newtonian ELMs. With the supported liquid membranes, 78-82% of the original PGM content could be recovered from model side-streams. The selectivity of the extraction for individual PGMs can be controlled by the extractant used

Monitoring of potable water quality in Makana Local Municipality, South Africa

The aim of this article is to examine the physicochemical and microbial water quality from 3 sampling sites spread across municipal drinking water supply grid in Makana Local Municipality, South Africa. Samples were analysed for the concentrations of faecal coliforms, heterotrophic plate count, the chemical oxygen demand, concentrations of ammonium, phosphate and chlorides. The chloride concentrations ranged from less than 0.01 to 7.60 ± 0.08 mg/L. At the same time, the ammonium concentrations were found ranging from 0 mg/L to 1.70 ± 0.23 mg/L. For the chemical oxygen demand, the measured values ranged from 55 ± 1 to 260 ± 18 mg/L. Finally, the phosphate concentrations were shown to vary between values which were lower than 0.01 mg/L up to 1.3 ± 2.0 mg/L. There were significant differences in the values of all chemical parameters between the various sampling points and the values measured on different sampling occasions (p-value < 0.01 in all cases, Kruskal-Wallis analysis and 5 % level of significance). A total of 16 drinking water samples were tested for microbial water quality and 75 % of all samples was free of faecal contamination as indicated by the faecal coliform concentration < 0 colonyforming units per 100 mL. This percentage is lower than the data of 92-100 % of samples free of faecal contamination as published by local government. The discrepancy can be effected by the hygiene habits of the household occupants or from regrowth of organisms in the drinking water distribution system in Makana. Examination of the microbial quality of water led to the discovery of the presence of Vibrio cholera and Aeromonas hydrophila

Microbial water quality of treated water and raw water sources in the Harare area, Zimbabwe

Microbial water quality is an essential aspect in the provision of potable water for domestic use. The provision of adequate amounts of safe water for domestic purposes has become difficult for most municipalities mandated to do so in Zimbabwe. Morton-Jaffray Treatment Plant supplies potable water to Harare City and areas surrounding Harare. This study investigated microbial water quality and the impact of microbial water quality related disasters in the area supplied by the Morton Jaffray Treatment Plant. Questionnaires were distributed to household owners in Harare who receive their water from the Municipality and those who use alternate water supplies. Candidates were randomly selected from their workplace. The raw water quality of Manyame River and its tributaries was assessed. Treated water in households was assessed for microbial quality using hydrogen sulphide test and heterotrophic bacteria plate count. Raw water sources were found to be contaminated by faecal matter. Household water sources tested negative for faecal contamination but positive for heterotrophic bacteria. CFU quantities ranged from 1 to 452 CFU/m. for all samples. The WHO guidelines for domestic water sources state that water used for domestic purposes should not be contain than 100 CFU/m.. Public perceptions of water quality ranged from eunsafef to ehighly contaminatedf. A decrease in the level of aesthetic appeal resulted in residents resorting to alternative sources such as wells and rivers for their domestic water. The current state of treated water was suitable for domestic use. Pathogen monitoring of domestic water is recommended using the hydrogen sulphide test and R2A agar test

Challenges and curriculum transformation in the higher education sector in South Africa: a case study in WASH to improve the training of pharmacists

South Africa is a member state of the “BRICS” bloc (BRICS2017.org, 2017) and the G20 group of the 20 nations/economic blocs, which between them account for the majority of the world’s trade and economic activity. It faces many developmental challenges which are mirrored in its higher education sector. In this article, the authors seek to provide an overview of the challenges that South African higher education faces in the achievement of the developmental goals of the country. The focus of this paper is a case study in WASH (water, sanitation and hygiene) to improve context-specific responses that trains pharmacists on knowledge and skills

Extended use of grey water for irrigating home gardens in an arid environment

The use of treated grey water (GW) for home gardens, peri-urban agriculture and landscaping is becoming popular in many water stressed countries such as Oman. This study aims to investigate the treatment efficacy, health and chemical concerns, cost-benefits and maintenance protocol of a GW treatment system as well as the effect of irrigation with GW on crop yield. Therefore, a decentralized homemade GW treatment system was installed in a newly constructed house in Muscat, Oman and studied over a 2-year period. The treated GW was found to be suitable for irrigation as per Omani standards. GW when mixed with kitchen effluent substituted the use of nutrient supplements for plants and did not show any harmful chemical or biological contamination. The capital cost of the system was around US $980, and the annual operating cost was US$78 with annual income and savings from the system being around US $572 indicating a payback period of nearly 2 years. It was found that the system required simple but regular maintenance particularly cleaning of the top layer of the filter. It can be concluded from this study that such a GW system should be technically, economically and environmentally feasible in Oman. Also, wider acceptance by the general public to the idea of GW reuse will help in mitigating the water shortage problem of the country to some extent

Efficiency of wastewater treatment by a mixture of sludge and microalgae

A combined system using the microalgae from South Africa and the sewage sludge from Algeria has been tested, in order to study the efficiency of wastewater treatment by mixtures of microalgae / activated sludge, five bioreactors were installed with different inoculation rates (microalgae / activated sludge) B1: 100% algae, B2: 90.90%: 9.1%, B3: 83.33%: 16.67%, B4: 50%: 50% and B5: 16.67: 83.33. The best removal percentages were measured as: 76.36% for PO4-P, 94.90% for NO3-N, 90.42% for NH4-N and 65.73% for COD, in the combined system. Except in the case of COD, there were highly significant effects of different inoculations rates on yield. The best results are those of the bioreactor B5. These results suggest that the nutrients in the wastewater can be effectively eliminated by co-cultivation of micro-algae with bacteria (activated sludge)