Evaluation of the Water Quality of River Kaduna, Nigeria Using Water Quality Index

Water is a natural resource of fundamental importance and supports all life forms. The study evaluated the water quality of River Kaduna using the Canadian Council of Ministers of the Environment (CCME) Water Quality Index. The study covered both raining and dry seasons in 10 sampling points. Water parameters analysed were turbidity, Zn, Pb, Cd, Cr, Cu, Mn, Fe, dissolved oxygen, electrical conductivity, pH, TDS and Ni using standard laboratory techniques. The data obtained were used to develop Water Quality Index (WQI) across the 10 sampling points and results showed that the water quality at Barnawa, Kudenda, Tudun Wada, Makera and Angwan Muazu are poor as their index values ranged between 31.8 – 42 while Kawo, Angwan Dosa, Malali, Kigo and Angwan Rimi are marginal as their index ranged between 45 – 61.3. The study concluded that the variety and level of contaminants in River Kaduna was related to the anthropogenic activities in the various parts of Kaduna Metropolis from where run-off and contaminants were received, hence, the water quality of River Kaduna is deteriorating. There is therefore the need for proper environmental education and discouragement in the use of toxic chemicals for farming so that pollution can be controlled at the source.&nbsp

Technical, Economic, and Greenhouse Gas Reduction Potential of Combined Ethanol Fermentation and Biofuel Gasification-Synthesis at Sulphite Pulping Mills

The integrated production of second generation biofuel at a sulphite mill, by ethanol fermentation of spent sulphite liquor (SSL), can be expanded by gasification-synthesis to produce synthetic fuels from bark residues available onsite. The potential contributions of such synthetic fuel production to economic and environmental performance of the integrated facility, in comparison to ethanol production that is accompanied by heat and power generation from bark, were determined. Thus, bark is used either for (i) direct heat and power generation via direct combustion in a high pressure boiler or a biomass integrated gasification and combined cycle (BIGCC) or, alternatively, for (ii) gasification-synthesis to produce either methanol or Fischer-Tropsch (FT) synthesis crude (syncrude). Techno-economic evaluations and calculations of the net greenhouse gas reduction (NGGRP) potential for all process scenarios were conducted on the basis of Aspen Plus^⊙ simulations. Combining synthetic fuels production with SSL-fermentation at sulphite pulp mills were shown to improve the liquid fuel yields from 15 to 69 MW_th on average, thus providing both acceptable NGGRP and investment opportunities that are financially viable. The internal rates of return (IRRs) were shown to improve from 25% for ethanol production only to 30% when combined with FT crude synthesis and to 32% when combined with methanol synthesis. Thus, negating disposal costs by utilizing waste biomass for combining synthesis fuels with ethanol production from SSL could be profitable at small scales, while maintaining the desired environmental benefits

Life Cycle Assessments of Waste-Based Biorefineries\u2014A Critical Review

In recent years advanced biorefineries based on organic residues and waste have gained increased attention for their potential to obviate first-generation bio-refineries environmental burdens. During the conceptual design phase of an advanced biorefinery the role of Life Cycle Assessment (LCA) is crucial for providing information on its envi-ronmental performances, better solutions, preferable process setup, more suitable feedstock, trade-off, and so on. This review focuses on advanced biorefineries LCAs in order to accomplish a synthesis of the state-of-the-art from the methodological point of view. Some main methodological issues have been analyzed and discussed on twenty-four LCAs. Attention has been drawn to functional units, system boundaries, invento-ry data collection, allocation methods and multifunctionality management ap-proach. Results show different approaches and solutions to the analyzed aspects but some clear addresses can be pointed out. It has been observed that LCA of biore-fineries can be classified in three different types in base on focal aim, and then functional units are consequentially defined. A large variability has been ob-served regarding system boundaries even if \u201ccradle-to-gate\u201d appears the most common. Inventories are mainly based on secondary data due to the very innova-tive features of the analyzed technologies. No general consensus has been ob-served concerning allocation of environmental impact between co-products