Investigation of water recycling in an anaerobic digester

Abstract: Anaerobic digesters (AD) are important biogas production units that convert waste to energy. In this paper, the water recycling will be investigated in the digestate of the AD as a way to utilize the scarce resources. Mostly, the digestate are put in dry bed for water vaporization and recovery of the solid bio-fertilizer. This paper focusses not only on extracting of the solid content, but it also focusses on capturing water such that it can be reused in the anaerobic digestion system. The tests that were performed are the accumulated mass, water quantity and water quality tests. The experimental matrix for testing were also designed. In the results, it was determined that most suitable material was 60 micrometre stainless steel mesh. This material was found to have a separation efficiency of 44% while recycling 77% of the water from liquid digestate. The material’s properties had a high durability, high corrosion resistance and high strength. This made the material long lasting and efficient for real life applications and due to its low corrosion, the recycled water does not have material impurities. The filtered water can be fed back into the digester while the filtrate can be used as a fertilizer

Alignment of water use licenses with strategic water management objectives for the uMkhanyakude District area, Kwazulu-Natal

MSc (Environmental Management with Ecological Water Requirements), North-West University, Potchefstroom CampusIn South Africa, water is a scarce resource and the National Water Act (Act No. 36 of 1998) makes provision for water resources to be used, controlled, protected, managed and developed to ensure sustainable use for all. The study was undertaken in the uMkhanyakude District Municipality (UKDM), situated in the KwaZulu-Natal (KZN) Province. The motivation for this research study is the on-going water shortages and droughts experienced in the Republic of South Africa (RSA), especially the UKDM. With the focus on the understanding by the members of the uSuthu to Mhlathuze Catchment Management Forum (CMF) regarding water governance in the area, a questionnaire was developed to capture the views and perspective of water users within the uSuthu to Mhlathuze Catchment Management Area (CMA). The idea was to gain an understanding of the knowledge of participants related to their authority regarding water governance and water management within the area. Of significance to the study was to incorporate the involvement of those within the CMF and their knowledge on water governance and its implementation. The collected data identified constraints and limitations experienced at catchment level and enabled the making of recommendations to address the issues currently faced by the catchment. A concern is that water uses to some extent of the RSA, especially country areas, are not regulated in an effective and efficient manner. This raises concerns about how water use is unaccounted for in some areas. The National Water Resource Strategy (NWRS) makes provision for instruments, such as Resource-directed Measures (RDM) and Source-directed Measures (SDM) to affirm that the nation’s water resources are shared equitably in order to ensure sustainability and the efficient use thereof and to ensure that water is not over-allocated or used and that the quality thereof is not compromised. Chapter 4, Part 1 of the NWA (1998) requires that water uses, as defined in section 21 of the Act, must be authorised. Thus, this raises a question to determine whether authorised water quantities are aligned with the predetermined water quantities of the uSuthu to Mhlathuze CMA. A literature review and secondary data from the Department of Water and Sanitation’s (DWS) Water use Authorisation and Registration Management System (WARMS) was used to determine whether issued water use authorisations of the uSuthu to Mhlathuze CMA are in line with strategic objectives of the area. The information gathered regarding water uses within the study area revealed allocations, different uses and users per sector. However, current information regarding the volume within the catchment could not be provided.Master

Equality before the law and access to justice in criminal proceedings under a bill of rights.

Thesis (LL.M.)-University of Natal, Durban, 1994.This work seeks to critically examine the right to legal representation in the South African criminal justice system under a future constitutional dispensation. Extensive attention has been given to how the right to legal representation has been interpreted under the common law. Reference has been made to the united States 6f America's approach to the due process and equal protection clauses in shaping the substantive and procedural content of the right to counsel in criminal proceedings. The importance of legal representation is examined during the pre-trial, trial and sentencing stages of criminal proceedings. A brief comparative examination has been made of the right to legal representation in other foreign jurisdictions, and how the courts have dealt with indigent accused persons facing criminal charges. Proposals from different quarters in South Africa have been discussed in the hope that these proposals may still find a place in the country's final constitution. Finally, the practical implications of a qualified right to free legal representation as provided by the Interim South African Constitution is discussed. Suggestions are also made concerning the approach to be adopted by the courts in the face of judicial precedents which would be in conflict with a new value system under a Bill of Rights after 27 April 1994

Pristine and modified mucuna beans adsorptive studies of toxic lead ions and methylene blue dye from aqueous solution

In this study mucuna beans were used for the removal of toxic Pb(II) ions and methylene blue dye from aqueous solution. The use of mucuna beans in water treatment application is largely unexplored. Therefore the current study is the first ever to report on mucuna beans as potential adsorbents. Mucuna beans were tested as adsorbents in pristine and chemically treated form. Batch adsorption experiments were conducted to evaluate the effect of systematic parameters such as the initial concentration, temperature, contact time and pH. The adsorbents were characterized by scanning electron microscope (SEM), thermogravimetric analysis (TGA), X-ray diffraction (XRD), fourier transformed infrared (FTIR) and Brunauer-Emmet teller (BET). SEM images revealed that acetone treated mucuna beans (Ac-MB), methanol treated mucuna beans (Me-MB) and dimethylformamide treated mucuna beans (DMF-MB) morphologies were dominated by spherical microstructures. FTIR analysis affirmed the presence of oxygen containing functional groups such as (–OH), (–COOH) and (–CO) attached to the adsorbents surface. These groups could enhance the adsorption processes. BET results also suggested that treated mucuna beans exhibits large pores, which could easily trap Pb(II) ions and methylene blue dye. It was observed that uptake of Pb(II) and methylene blue increased with increase in initial concentration of solution. However, all adsorbents had higher adsorption capacity for methylene blue molecules than Pb(II) ions. Also adsorption rate of methylene blue was faster, achieving equilibrium in 20 min and Pb(II) ions in 90 min. Enhancing the temperature of the solution had a positive effect on the removal of Pb(II) ions by UT-MB and Ac-MB, while for methylene blue it was Me-MB and Ac-MB revealing the exothermic nature of the processes. However, increasing the temperature was detrimental on the adsorption of Pb(II) ions onto Me-MB, AA-MB and DMF-MB, for methylene blue it was onto DMF-MB, UT-MB and AA-MB revealing the endothermic nature of the processes. The maximum adsorption capacities were obtained at pH 9 for both pollutants, Pb(II) adsorption capacity trends were UT-MB > Ac-MB > DMF-MB > AA-MB > Me-MB (19.96, 18.94, 17.60, 16.17 and 16.15 mg/g) respectively and for methylene blue were Me-MB > DMF-MB > UT-MB > Ac-MB > AA-MB (24.56, 23.89, 22.86, 22.78 and 22.55 mg/g). Pb(II) adsorption onto all adsorbents fitted Freundlich model. Methylene blue adsorption onto UT-MB and Ac-MB fitted Langmuir model, while Me-MB, AA-MB and DMF-MB fitted Freundlich model. Kinetic studies revealed that all adsorption processes found good fit for PSO model. However, Pb(II) ions adsorption onto AA-MB and DMF-MB had good fit for PFO model. The reusability of the adsorbents was also tested. Keywords: Mucuna beans, Methylene blue, Lead, Kinetics, Thermodynamics, Equilibriu

Problematising race for journalists: critical reflections on the South African Human Rights Commission Inquiry into media racism

How journalists report race and racism was at the centre of the South African Human Rights Commission (SAHRC) Inquiry into racism in the media. A critical analysis of the conceptual assumptions in the Inquiry's Final Report, however, reveals serious limitations to the enterprise. In particular the flawed conceptualisations, plus the generalised character of the findings are of little help in assisting the momentum of eradicating racism in South African media, and for linking race transformation to issues of class, gender, sexual orientation and xenophobia. This article identifies the problems as race essentialism and a relativism about what constitutes racism. It argues instead that journalists need the concept of racialisation in order to change their reporting. The argument upholds the desired role of the South African media as one that contributes to a non-racial, as opposed to a multi-racial, society