Green Preservation of Goatskin to Deplete Chloride from Tannery Wastewater

Globally, in wet-salting preservation, common salt (sodium chloride, NaCl) is generally practiced for the raw animal skin which emits a huge amount of chloride-containing wastewater affecting groundwater quality, human and plant life. Chlorides in tannery wastewater encourage salt-free or less-salt preservation methods of raw skin. In this study, an alternative salt-free ‘green method’ has been described for goatskin preservation with rapidly growing obnoxious weeds Sphagneticola trilobata leaf. The ‘green leaf paste’ was applied on the flesh side of the raw goatskin and compared with conventional wet-salting (50% NaCl) method for 28 days. Different parameters of both sample like moisture, nitrogen, hydrothermal stability, and bacterial growth were periodically assessed and compared. Shoe upper leather was produced from both preserved goatskins. After comparing with standards, the physical properties like tensile strength, elongation at break, bursting strength satisfied the standard requirements. SEM images showed no deterioration to the fiber structure of both samples. Moreover, the suggested method reduces the pollution loads: chloride, total dissolved solids, biochemical oxygen demand, and chemical oxygen demand by 98.04%, 92.9%, 90.2%, and 85.5%, respectively. The overall assessment recommends that the salt-free ‘green method’ utilizing S. trilobata leaf paste could be an attractive system over the conventional wet-salting method. Doi: 10.28991/HIJ-2021-02-02-03 Full Text: PDF

A Review of Eco-Friendly Preservative and Bio-Tannin Materials Using Powdered Barks of Local Plants for the Processing of Goatskin

Skin is a raw material which is considered as the heart of leather making process. Skin falls vulnerable upon the flayed of the animals and is seriously invaded by bacteria if it is not well protected. Curing and preservation of raw stock resist putrefaction and reserve leather quality. Worldwide, most commonly used skin preservation is by using table salt which is accused of polluting the environment by increasing soil salinity, affecting water body, releasing more than 40% dissolved solids and 55% chlorides etc. Further, on the side of leather tanning, 80-90% of all leathers is manufactured by tanning with basic chromium (III) salt, because of its excellent features and is also solemnly accused that; its safety record is cautionary, uncontrolled emission of chromium (VI) and it is a limited natural resources. Pollution control authorities of many countries are imposed severe restrictions on both salt preservation and chrome tanning forcing the tanners and researchers to look for possible alternative ways that are naturally abundant, easily obtainable, low priced, eco-friendly and offer competitive with existing tanned leather performances. The critical reviewed was targeting the recent alternatives trends to skin/hides salt preservation as well as vegetable tanning as a possible way to replace the use of basic chromium salt for the sustainability of leather industry and to further suggest another preservative and vegetable plant to be used in future studies.

STUDY ON PRODUCTION POTENTIAL AND PRESERVATION METHODS OF HIDE AND SKIN IN THREE SELECTED DISTRICTS OF GAMBELLA REGION, SOUTH WEST ETHIOPIA

Ethiopia is believed to have the largest livestock population in Africa. An estimate indicates that the country is a home for about 54 million cattle, 25.5 million sheep and 24.06 million goats. Therefore, this study was conducted in three selected districts of Gambelia regional state with the objective to assess the production potentials and preservation methods of hide and skin. As a secondary product of the meat consumption, the supply of hides & skins depends on the demand for meat, the rearing, management and slaughtering of animals, with little response to change in price and demand for the products. Hides and skins could be obtained from fish, birds and reptiles as well as wild and domesticated animals. The sample size of the study was estimated to be 384 (128 from Gambella zuria, 128 from Godare and 128 from Lare) using the formula stated in Thrust field. The quantitative data was organized, summarized and encoded on excel sheet and analyzed with the help of Statistical Analysis System (SAS) 9.2 version 2008.Qualitative data derived from direct observations and key informants was examined and presented in form of discussions. In the study areas, for all the three species, the mean annual slaughter at household level ranges between 0.07,1.66 and 1.73 cattle, sheep and goat annually, respectively in the study area. Of the 384 respondents interviewed, (94.01%) used the preservation methods of ground air dry and 6.25% use salt preservation for hide and skin preservation, respectively. Generally, production potential and preservation methods variations were observed among the Hide and skin producers, which suggest that there is an opportunity for improvement through awareness creation.