The aqueous extract from the bark of the black wattle tree, (Acacia mearnsii De Wild)(1), is used extensively in the tanning industry for the production of sole and other heavy leathers as well as in lighter leathers and skins. The commercial extract is available in an easily dissolvable spray dried form and in deference to its genus name Mimosaceae is referred to in the trade as Mimosa(3). Mimosa extract consists primarily of high molecular weight polymeric flavonoid units which also constitutes the active tanning ingredient. Lower phenolics, gums and sugars or the so called "non-tannins" are present as impurities and contribute up to 40% to (3 ) the total mass of the extract.

M.Sc. / Waste generation and waste disposal forms part of our everyday lives, even more so for a tanning facility. This mini dissertation discusses the delisting of waste generated at a tanning facility. This facility produces crust leather from partially tanned hides received from other tanneries in the Mpumalanga province. Crust leather is the product in the penultimate process before it attains its desired leather like properties. The crust leather is sent to a finishing plant for the final process of painting before it is supplied to the automotive industry for upholstery purposes. Large volumes of raw materials including chemicals, water and hides are used in the retanning process to produce crust leather. During the production of this leather various waste streams are generated including effluent, solid waste and tanning sludge. The tanning sludge is classified in terms of the Department of Water Affairs and Forestry’s Minimum Requirements for Handling, Classification and Disposal of Hazardous waste as a possible or potentially hazardous waste. Hazardous waste must be disposed of to a permitted hazardous waste landfill site which has a significant cost implication for the tanning facility. This mini-dissertation focuses on the attempt to delist the tanning sludge. This mini-dissertation highlights the problems associated with hazardous waste disposal in the form of sludge from the tannery. This disposal is expensive because there is only one permitted hazardous waste landfill site in the Gauteng and Mpumalanga provinces. This site is called Holfontein and is situated approximately 200 km from the tanning facility. The high disposal cost encountered is owing to the specialist management required because of the environmental risks involved in operating this waste disposal site. However, an option to delist the hazardous tanning sludge waste is available to the tanning facility, which could mean that the hazard rating is reduced from extremely hazardous to a lower rating or even to general waste. Delisting the tanning sludge will allow it to be disposed of to a general landfill site. Previous attempts to delist the tanning sludge were not successful as the presence of hexavalent chromium (Cr (VI)) and cyanide (CN) in the tanning sludge caused it to remain classified as extremely hazardous waste. Due to the increasing waste disposal cost the tanning facility once again engaged in the processes to delist the tanning sludge. The personnel of the tanning facility is of the opinion that hexavalent chromium (Cr(VI)) and cyanide (CN) should not be present in the tanning sludge as these substances are not used generally in the tanning industry. Therefore, the main aim of this mini-dissertation is to delist the tanning sludge to general waste thus allowing it to be disposed of to a general landfill site, which in turn will result in a reduction in the waste disposal costs. Delisting of hazardous waste produced in a tannery In order to achieve the main aim, the study entailed a literature review of the retanning process explaining the generation of the various waste streams, the possible presence of chromium (Cr) and hexavalent chromium (Cr(VI) in the process, and a review of the environmental legislation that will determine the waste disposal options. To delist the tanning sludge the tanning facility followed a defined procedure as determined by the Department of Water Affairs and Forestry. The tanning sludge was assessed using analytical procedures as specified. The objective was to characterise the leachability of the tanning sludge, as well as to verify the presence of any hazardous substances which prevent the tanning sludge from being delisted. Leachability is the potential mobilisation of substances from the sludge under circumstances similar than that of the waste disposal sites. This includes the presence of hexavalent chromium (Cr(VI)) and cyanide (CN) in the tanning sludge. In an approach to verify the presence of hexavalent chromium (Cr(VI)) and cyanide (CN) in the tanning sludge the composition of the raw materials (chemicals and hides) were evaluated and samples were taken from the various effluent streams. The tanning sludge was sampled separately to determine the leachability characteristics. No hexavalent chromium (Cr(VI)) and cyanide (CN) were found to be present in the raw materials or in any of the waste effluent streams. However, small quantities of cyanide (CN) and hexavalent chromium (Cr(VI)) were found to be present in the tanning sludge. The reason for the presence of these constituents could not be determined as it was proved that hexavalent chromium (Cr(VI)) and cyanide (CN) do not enter the process through the raw materials. It was further proved that the process does not support circumstances to oxidise trivalent chromium to hexavalent chromium (Cr(VI)). Further, the presence of cyanide (CN) cannot be explained since it is not a substance that is generally used in the tanning industry. Part of the study included determining treatment options for the tanning sludge. It was found that treating the tanning sludge with lime reduced the concentration of heavy metals such as hexavalent chromium (Cr(VI)). However, after analysis and classification of the tanning sludge it was found that it was not the hexavalent chromium (Cr(VI)) and cyanide (CN) that prevented the tanning sludge from being delisted to a lower hazard rating but rather the presence of small quantities of cadmium (Cd). Cadmium (Cd) is classified as extremely hazardous and therefore it is this substance that is responsible for the high hazard rating classification of the sludge. Although the objective to delist the tanning sludge was not achieved, it was determined that the waste can be disposed of to a general waste landfill site permitted to accept a certain amount of waste containing heavy metals (such as chromium and manganese). The reduction in the waste disposal cost will therefore be achieved and the tanning facility will dispose of their waste in a Delisting of hazardous waste produced in a tannery sound and environmentally responsible method ensuring it will not have a significant impact on the environment.

Thesis (Master)--İzmir Institute of Technology, İzmir, 2006. / Keywords: Conservation, tourism, production buildings, refunctioning, Kuşadası. Includes bibliographical references (leaves. 204).

Saline deterioration in the South African public water system has been documented and disposal of brine wastes has been identified as part of the problem. The broad aim of this research programme was to undertake an initial technical study to evaluate the feasibility of integrating algal biotechnology into a disposal function for these wastes. A demonstration of utility in the form of products and waste treatment could produce a beneficiation of saline effluents and provide incentives necessary to deal with the disposal issue. The study attempted to demonstrate a synthesis between the two main thrusts in algal biotechnology that have produced large-scale practical applications - stable, predictable algal production in saline media and the cost effective High Rate Oxidation Ponding (HROP) process for incorporating algal production into a waste treatment function. Tannery organic saline effluents and the biotechnology of Dunaliella salina culture producing β- carotene were chosen as paradigms for the study. 1. The alga was shown to grow in certain tannery effluents producing enhanced biomass yields compared to defined inorganic medium cultivation. The potential for amino acid or protein supplementation of defmed culture media was noted. 2. A reduction in organic load simultaneous with the growth of D.salina was recorded in laboratory-scale simulations of the HROP process. Rates similar to the fresh water HROP equivalent were demonstrated. 3. These results suggested the uptake and storage of organic nitrogen by D.salina. The consequent inhibition of β-carotene accumulation by the organism presented a potentially insurmountable obstacle to the feasibility of β-carotene production in this medium. Uptake and release of organic compounds, previously demonstrated in phytoplankton and other micro-algae, was confirmed in this study for D.salina. The evidence acquired indicated the internalization of both glycine and bovine serum albumin. An ultrastructural study demonstrated mechanisms by which this process might occur. 4. The release of substantial quantities of glycerol was shown. A mechanism whereby D. salina may use this to regulate ammonia availability via control of its associated bacterial population was observed. Glycerol release was identified as presenting an application in treating refractory organic wastes, such as secondary sewage sludges, by elevating C:N ratios. This could demonstrate a significant utility for brine waste impoundments. 5. A multistage production process was proposed to deal with the problem of β-carotene inhibition by separation of the growth and metabolite accumulation functions into separate unit operations. It was shown in this study that the stress of nitrogen deficiency combined with high salinity provides for effectiveβ-carotene accumulation under the conditions of low illumination that pertain in dense cultures. Subjected to these conditions effluent-grown cells show delayed but unimpaired {j-carotene accumulation. 6. A role for the plant hormone abscisic acid in mediating the stress response was demonstrated in D.salina. Fluorescence induction studies suggested the presence of a signalling process forming part of a sensitivity control mechanism. Stress induction of β-carotene accumulation could occur through four clearly defined stages. Potential was identified for using this response as a physiological probe for monitoring and regulating the stress induction process. 7. The multistage processing concept requires effective algal cell separation technology. The use of cross-flow ultrafiltration and diafiltration with a polyethersulfone tubular membrane system was demonstrated as an effective process for the recovery and washing of D. salina. Cell concentrates were produced in a viable form. 8. Process designs incorporating the findings of the research programme are presented demonstrating how effluent and organic waste treatment functions may be combined with the production of D.salina and its products. Application of the multi-stage processing concept to β-carotene production in a defined medium process was identified as offering a potential four-fold yield enhancement. This could have a significant impact on a high cost, marginal algal biotechnology process. Aspects of novelty have been claimed in provisional patents applications. A provisional demonstration of the feasibility of D.salina production in tannery effluent indicates that algal biotechnology may provide a utility for, and hence the beneficiation of saline effluent wastes.

Salinisation has been identified as a major cause of the progressive deterioration in the public water system in South Africa. To deal with this problem Waste Stabilisation Ponding systems have been used by the Leather Processing Industry as zero-dischaJ;ge wastewater evaporation disposal processes in water-limited inland regions of the country. While effective in the evaporation disposal function these systems are plagued by the generation of serious odour nuisance creating intractable environmental problems relating to adjacent residential communities. High loading to ponds of organic compounds, sulphides and ammonia results in strongly reducing anaerobic conditions prevailing in early parts of pond cascades. These are characterised by bright red colours due to the predominance of purple photosynthetic bacteria. Sporadic micro algal blooms of Spirulina sp. and Dunaliella sp. had been previously noted to occur on the latter ponds in these cascades, and were associated with their conversion to facultative function, with aerobic surface layers, and a marked reduction in odour release. This research programme undertook an investigation of the microbial ecology of a tannery waste stabilisation ponding system to describe factors which give rise to these blooms, and to determine whether microalgal growth may be manipulated to achieve a reliable oxygengenerating capping of the anaerobic ponds. The predominance of near pure cultures of Spin/lina platensis was demonstrated for the blooms and factors restricting its growth in the system were described. These include the interaction of ammonia and sulphide toxic effects and laboratory studies were undertaken to show how effluent loading may be regulated to enable effective growth of the cyanobacterium. At appropriate dilutions of tannery effluent an enhancement of growth was noted, compared to growth in defined mineral medium. An investigation of this phenomenon provided preliminary evidence for organic uptake by the pond micro algae and a possible contribution to heterotrophic nutrition. The manipulation of Spirulina sp. growth in a High Rate Algal Pond raceway was undertaken in outdoor pilot plant studies and the effect of microalgal capping of the anaerobic ponds in the cascade was demonstrated by activating a recycle loop from a blooming facultative pond. Heavy metal contaminants were effectively eliminated by an optimisation of the primary anaerobic pond function and precipitation as metal sulphides. Biomass was harvested and dried, during which a range of methods were evaluated. Toxicological studies were undertaken on the dried biomass using Artemia and chick assays, and feed studies showed its useful application in rations for the abalone Haliotlls midae and rainbow trout Onchorhynchlls mykiss. Based on positive independent assessment of research outcomes, a decision was made by the tanning company operating the Waste Stabilisation Ponding system, to proceed to the construction of a full-scale 2 500 m2 High Rate Algal Pond raceway. This would be used for controlled Spirlilina biomass production to effect a practical capping of the anaerobic ponds in the system, and to evaluate its commercial potential in the feed market. The Advanced Integrated Wastewater Ponding System described by Oswald (1991) provided the conceptual basis for the Algal Biotechnology process development undertaken. The studies of the microbial ecology and the biotechnological potential of this system have shown that a Spirulina-based High Rate Algal Ponding process can be engineered in such a way that saline tannery effluents may be treated to effect a significant reduction in overall pollution load, that biomass may be recovered as a value added product of the treatment process and that the operational performance of Waste Stabilisation Ponding systems, and hence their immediate environment, may be improved by the use of the High Rate Algal Pond as a retrofitted upgrading unit operation.

The considerable volume of chromium-bearing wastes generated during the process of leather tanning, exacerbated by the potential for trivalent chromium in the wastes to be oxidised to the toxic hexavalent state, has created a major waste disposal dilemma for the tanning industry. While methods are available for the safe and effective treatment of residual chrome-tanning liquors, little has been done to address the issue of the chrome-bearing solid wastes. Given the increasingly stringent environmental compliance standards facing tanneries, unless an appropriate treatment process is developed in the immediate future, the continued use of chromium as a tanning agent could be compromised. Recent investigations have demonstrated the potential of heated alkaline conditions for dechroming these solid wastes. This study expanded upon these considerations and examined the feasibility of utilising the highly alkaline tannery waste effluents as cost-effective, substitute alkaline media. The three effluents considered in this study, classed as lime sulphide liquors, were shown to be capable of dechroming wet blue shavings, with resultant separation of the solid wastes into a protein and a concentrated chromium product. The solubilised protein product contained low chromium concentrations which comply with legal discharge limits. The precipitated chromium product offers opportunity for reutilisation in the tannery. A novel industrial-scale treatment process, based on these investigations, indicated the process to be capable of treating the quantity of shavings produced on a daily basis by a medium to large scale tannery. Application of this method for the dechroming of other chrome-tanned solid wastes was also shown to be feasible.

Worldwide chromium waste from tanneries is a major environmental concern. A considerable amount of effort is being implemented by tanneries to resolve the environmental concerns. Because of the wide range of chemicals used in tanning, waste treatment is an important issue in the industry. All the tanneries put considerable money and effort into treating their effluent. South African tanneries currently have various methods of disposing of their chrome waste. Most have systems for recycling the waste and disposing of it in municipal waste dumps or it is dumped on the company's own land. Hence the cost of disposal varies widely. Some companies are forced to pay excessive amounts to dispose of their waste at hazardous waste dumps. Others appear to get away by using municipal dumps. Trivalent Chrome (Pty) Ltd offers a solution to the environmental concern by extracting the most dangerous compound in the waste and converting it to a by-product (green chrome oxide). However, the company must be able to then sell of the green chromium oxide. The study seeks to address how the company can market the by-product.

M.Com. (Business Management) / Please refer to full text to view abstract

Submitted by Erika Demachki (erikademachki@gmail.com) on 2014-10-06T11:03:18Z No. of bitstreams: 2 Dissertação - DAIANE GONÇALVES RIBEIRO - 2013.pdf: 19061537 bytes, checksum: 9518094e500b8d33e156ef7961e7c513 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2014-10-06T15:39:25Z (GMT) No. of bitstreams: 2 Dissertação - DAIANE GONÇALVES RIBEIRO - 2013.pdf: 19061537 bytes, checksum: 9518094e500b8d33e156ef7961e7c513 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2014-10-06T15:39:25Z (GMT). No. of bitstreams: 2 Dissertação - DAIANE GONÇALVES RIBEIRO - 2013.pdf: 19061537 bytes, checksum: 9518094e500b8d33e156ef7961e7c513 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2013-10-08 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / This study refers to an investigation about competitiveness of syndicated tanneries in Goiás State, using as standard the tanneries situated at Vale do Rio dos Sinos – RS. The research question was: which indicators reflect the tanneries competitiveness? The general objective of this research was analyzing the syndicated tanneries competitiveness of Goiás state. It was used as method the exploratory research, the bibliographic and documental survey, the field research, the interviews and the observation. As a result it was diagnosed that the syndicated tanneries of Goiás have enough competitiveness to keep themselves in the inside market and in the exportation to Europe and Asia. And as a final consideration it is expected that this research contributes to the leather chain development in Goiás and enlarge the approaches that make possible the evaluation of the organizational competitiveness. / Este estudo refere-se a uma investigação voltada à competitividade dos curtumes sindicalizados no Estado de Goiás, utilizando como parâmetro os curtumes localizados na região do Vale do Rio dos Sinos – RS. O problema de pesquisa definido foi: quais os indicadores refletem a competitividade dos curtumes? O objetivo geral desta pesquisa foi analisar a competitividade dos curtumes sindicalizados do Estado de Goiás. Utilizou-se como método a pesquisa exploratória, o levantamento bibliográfico e documental, a pesquisa de campo, as entrevistas e a observação. O resultado diagnosticou que os curtumes sindicalizados do Estado de Goiás possuem um suficiente grau de competitividade para manter-se no mercado interno e na exportação para Europa e Ásia. E como consideração final, espera-se que esta pesquisa contribua para o desenvolvimento da cadeia de couro de bovino no Estado de Goiás e amplie as abordagens que possibilitem a avaliação da competitividade organizacional.

Thesis (Ph.D.)--University of Adelaide, Dept. of Soil and Water, 2002. / Bibliography: leaves 166-180.