Technical–economic evaluation of a small-scale model plant for the manufacture of pine glue laminated timber

A small-scale glue laminated timber (GLT) model plant, capable of producing an average of 880 linear m of lamellas per day, approximately 1500 m³/year, located in Castilla y León, Spain, was technically and economically evaluated. The production of such plant is aimed at substituting imports of GLT manufactured from spruce in Central Europe. The total investment considered for this theoretical operation was 455 k€. The raw material proposed was Pinus sylvestris classified according to UNE 56544 as ME-2. The external lamellas were defined as ME-1, upgraded from ME-2 by the removal of knots and deformations, which gives an average block length of 1825 and 3800 mm for external and internal lamellas, respectively. The effective stiffness of such configuration was modeled, rendering beams that could be assigned to class resistance GL24. Production costs were 770 k€, 52% of which were timber as raw material. The volume of production is affected by the combination of products manufactured; therefore, this variable was presented as a function of economic result, defining zones of product-mix that would be economically unfeasible, feasible with reservations, and feasible. The products to be manufactured were straight beams, 6-m long, of 9 different cross-sections, varying from 80?×?120 mm² to 200?×?600 mm². Additionally, production volume, wood cost, and block length are identified as critical parameters for the sensitivity analysis of the plant. Considering a wood cost for ME-2 of 220 €/m³, the plant must operate at 70% of its capacity to be economically feasible. The economic result of the operation increases proportionally to block length. The plant generates an EBIT of 51 k€, PNV of 415 k€ (discount rate of 4%), and an IRR of 19%.

     

Determination of Moisture Content in Ceramic Brick Walls Using Ground Penetration Radar

The moisture content in ceramic masonry plays an important role in their performance and durability, also serviceability is severely affected by moisture. The presence of moisture represents one of the major issues associated with structures fabricated with ceramic masonry. The intrinsic characteristic of the material along with the age of the structure plays an important role in the amount of moisture absorbed by the walls. Traditional methods for determining the moisture content of in-situ masonry walls are many times destructive or semi-destructive and provide limited information. In this study, ground penetrating radar is used as a non-destructive technique for measuring the moisture content in ceramic masonry walls. Control samples were used as calibration in the laboratory and field measurements were performed to determine the moisture content of the ceramic walls. The developed methodology was applied to real size ceramic walls, were in-situ measurements showed areas with different moisture levels. The methodology developed showed to be fast and easy to use in the field for measuring the moisture content of ceramic brick walls.     

Continuous Lipase-Catalyzed Alcoholysis of Sunflower Oil: Effect of Phase-Equilibrium on Process Efficiency

Phase-equilibrium diagrams of biodiesel synthesis substrate (oil/alcohol/alkyl esters) and product (alkyl esters/glycerol/alcohol) mixtures containing methanol, ethanol and propanol, respectively, were used for the identification of those composition ratios leading to mixture homogeneity. Based on the diagrams, complete conversion of the substrate oil contained in a sunflower oil/ethanol/ethyl ester mixture at a weight ratio of 7.6:11.4:81.0 resulted in the generation of an amount of glycerol capable of remaining in solution in the product mixture. In contrast, complete conversion using a mixture of a lower alcohol and ethyl ester content (19.0:6.0:75.0) leads to the separation of phases. A continuous reactor charged with Lypozyme TL-IM and fed with the former mixture showed constant conversion and productivity with time, whereas process efficiency was found to decrease drastically when the latter mixture was fed. When a sunflower oil/isopropanol/isopropyl ester mixture at a weight ratio of 35:35:30 was fed in the reactor charged with Novozym 435, the output glycerol concentration was equivalent to that theoretically expected. In contrast, feeding a sunflower oil/ethanol/ethyl ester mixture of equal proportions as above, the glycerol concentration was lower than expected, suggesting the occurrence of glycerol adsorption on the enzyme support.