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Water hyacinth (WH, Eichhornia crassipes, ’Emboch’ in Ethiopia) is a highly disturbing class of invasive and noxious aquatic plants found worldwide in other water bodies and as such is a prime problem in Lake Tana. One approach to successfully control the rapid invasion of WH is to utilize it as a feedstock to produce high-valued commodities in a biorefinery framework. Preliminary life cycle analysis carried out in the study shows that WH biomass is a competitive feedstock for biorefinery systems with a unit cost at $ 24.40 per ton of dry matter. Based on the annual generation capacity of 0.71 million tons of dry mass in lake Tana and following the standard biorefinery process protocols, the predictions indicate that the economic potential of converting WH biomass into 38.8 billion liters of biomethane alone to be at $ 38.8 million, 74.2 million liters of bioethanol alone at $ 51.9 million, and o.52 million tons organic agro-fertilizer alone at $ 130.5/78.3 million as a partial substitute for Anhydrous Ammonia or Muriate of Potash (MOP) fertilizers. Hence the integrated WH management and utilization as a biorefinery feedstock ranks it among the world’s most competitive feedstocks with attractive socio-economic and environmental benefits.

When buildings are exposed to earthquake sequence, damage aggravation is expected to occur. Although several studies report seismic vulnerability of reinforced concrete (RC) buildings under the mainshock–aftershock sequence, indicating damage aggravation due to aftershock, none, to the best of our knowledge, quantifies seismic vulnerability of buildings under foreshock–mainshock–aftershock sequences. Since foreshock–mainshock–aftershock sequences are also expected in many active seismic regions, we aim to quantify the level of vulnerability under seismic sequences considering the seismically highly active Himalayan region as the case study location. Fragility functions are derived considering foreshock, foreshock–mainshock sequence, and foreshock–mainshock–aftershock sequence for a low-rise special moment-resisting frame (SMRF) building that represents a typical low-rise owner-built construction system in Nepal, one of the most active seismic regions in the world. The results highlight that the foreshock significantly increases seismic vulnerability of the structures with respect to the often-considered case of a mainshock–aftershock sequence.

This work presents an updated techno-economic assessment of methanol production, considering an entrained flow gasifier with different second generation biomasses. Computer simulations were performed with the aid of a gasification simulator GasDS and with commercial process simulator Aspen HYSYS. A method was proposed to determine biomass composition in terms of cellulose, hemicellulose and three surrogate compounds that account for the most abundant monomers that compose lignin chains; the lower heat value (LHV) relative error was not bigger than 10%. The kinetic model deriving from this biomass characterization (composition) is not sufficiently accurate to describe biomass gasification; this is due to unrealistically small residence times and the (not modelled) catalytic effect of molten slag. Biomass gasification output is efficiently estimated by using chemical equilibrium. At current methanol market price (350 €/t) the process is economically unfeasible at the current plant capacity of 100 MW LHV biomass input (production costs vary between 360 and 440 €/t).

In this paper matrix and vector products are exploited to reformulate Bender Equation of State. Finally, the new formulation is used to generate results which has been compared with experimental data sets available in literature and the analogous findings coming from different thermodynamic packages commonly used in Aspen Hysys for Air Separation Unit.