Hidrólisis y separación de biomasa lignocelulósica en un proceso al sulfito con el objeto de valorizar las principales fracciones dentro del concepto de bio-refinería

ABSTRACT: Physico-chemical and biological processes can be used to transform different pulp and paper industries through integrated forest biorefineries in order to valorise all of the main fractions of the lignocellulosic biomass (cellulose, hemicellulose and lignin). In this work, hydrolysis and fractionation processes have been studied in a sulphite pulp mill to obtain not only dissolving pulp from the cellulose but also lignosulphonates from the lignin and fermentation products from the hemicellulose. Delignification and hydrolysis experiments have been carried out at laboratory scale in order to increase the valorization opportunities and trying to decrease the inhibitors in the final by-product. In addition, detoxification or separation treatments have been developed in order to separate the lignosulphonates and other inhibitors from the sugar substrate.RESUMEN:Diferentes procesos físico-químico y biológicos se pueden utilizar para transformar la industria de la pasta y celulosa en bio-refinerías forestales integradas, con el objetivo de valorizar las principales fracciones de la biomasa lignocelulósica (celulosa, hemicelulosa y lignina). En este trabajo se han utilizado diferentes procesos de hidrólisis y fraccionamiento en una industria de pasta celulósica con el fin de obtener no solo la pasta dissolving sino también lignosulfonatos procedentes de la lignina y productos de fermentación de la hemicelulosa. Se han llevado a cabo diferentes experimentos de hidrólisis y deslignificación a escala laboratorio para aumentar las oportunidades de valorización y tratando de disminuirla producción de inhibidores en los sub-productos. Además, se han desarrollado diferentes procesos de detoxificación o separación con el objeto de separarlos lignosulfonatos y otros inhibidores del sustrato de azúcar.Los autores desean agradecer la ayuda de este trabajo al proyecto Europeo KBBE-2012-6-311935 bajo el séptimo programa marco de la Unión Europea. www.brigit-project.eu

Influence of input variables over the wood digestion in a sulfite pulp mill for biorefinery purposes

Eucalyptus globulus is the most profitable specie in Europe for pulping. However, in recent years some diseases and pests have caused its defoliation, affecting the available quantity of wood. In this sense, the mills are studying how to avoid the loss of pulp yield as well as the optimization of byproducts in order to take advantage of every component present in the wood using biorefinery processes. One of the possible options is to complete the consumption of E. globulus with other species such as Eucalyptus nitens. The objective of this paper is to study the behavior of both species related to the dissolving pulp manufacturing process as well as the characteristics of the resulting products. Parameters that can be very useful for the evaluation of the raw material, such as the growing data or density of both species, have been compared. Major attention has been focused on the composition of both species and how it affects the characteristics of the possible final products. E. nitens presents good results of forestry characteristics, being better than E. globulus in terms of growing and resistance to frosts. The cellulose content of both species is similar, however the digestion process in the case of E. nitens needs to be improved in order to optimize the involved energy and the obtained products.The authors gratefully acknowledge the financial support for this research by the KBBE-2012-6-311935 research project under the European Union Seventh Framework Programme. www.brigit-project.eu

Waelz slag-based construction ceramics: effect of the trial scale on technological and environmental properties

The construction industry has already begun the transition to circular economy and intensive research has been conducted over the last decades at laboratory scale to assess the potential use of waste in ceramic applications. However, industrial trials to prove its scale up have been performed to a lesser extent. This work studies the effect of trial scale on the technological and environmental properties of high quality ceramic products incorporating Waelz slag (WS), an industrial by-product from the recovery of electric arc furnace dust. To this aim, three groups of ceramics have been produced varying the WS content and the process parameters, moulding water and pressure, at laboratory and industrial scale. Preliminary laboratory scale tests were used to optimize WS content and process conditions using the software GAMS (General Algebraic Modeling System). Optimum ceramic products were processed at both laboratory and industrial scale and tested for their technological and environmental properties. Results from the laboratory and industrial trials were compared to evaluate the scale effect on the ceramic properties. The introduction of WS in clay bricks seems to be easily scaled-up for additions of WS ≤ 10wt%, but higher percentages of WS promotes relevant differences in the properties of the laboratory and industrial bricks.This work has been funded by the Spanish Ministry for Education and Science (Project CTM 2009-11303). The authors gratefully acknowledge fnancial support for this research from BEFESA STEEL R&D, S.L.U.C. Company at Asua, Vizcaya, Spain

Evolution of lignocellulosic macrocomponents in the wastewater streams of a sulfite pulp mill: a preliminary biorefining approach

The evolution of lignin, five-and six-carbon sugars, and other decomposition products derived from hemicelluloses and cellulose was monitored in a sulfite pulp mill. The wastewater streams were characterized and the mass balances throughout digestion and total chlorine free bleaching stages were determined. Summative analysis in conjunction with pulp parameters highlights some process guidelines and valorization alternatives towards the transformation of the traditional factory into a lignocellulosic biorefinery.The results showed a good separation of cellulose (99.64%) during wood digestion, with 87.23% of hemicellulose and 98.47% lignin dissolved into the waste streams. The following steps should be carried out to increase the sugar content into the waste streams: (i) optimization of the digestion conditions increasing hemicellulose depolymerization; (ii) improvement of the ozonation and peroxide bleaching stages, avoiding deconstruction of the cellulose chains but maintaining impurity removal; (iii) fractionation of the waste water streams, separating sugars fromthe rest of toxic inhibitors for 2nd generation biofuel production. A total of 0.173 L of second-generation ethanol can be obtained in the spent liquor per gramof dry wood.The proposed methodology can be usefully incorporated into other related industrial sectors.The authors wish to express their sincere gratitude to the Sniace personnel and the financial support of the European Union by the BRIGIT “new tailor-made biopolymers produced from lignocellulosic sugars waste for highly demanding fire-resistant applications” research project http://www .brigit-project.eu/

Incorporation of Waelz slag into the ceramic sector: Practical example of Industrial Ecology

RESUMEN: La recuperación de Zn de polvos de acería mediante el proceso Waelz genera como subproducto una escoria denominada Ferrosita o escoria Waelz. Este subproducto, con elevadas cantidades de óxidos de hierro, óxido de calcio y sílice, puede ser objeto de utilización por parte de otras empresas mediante la incorporación como recurso a otro ciclo productivo. Tras el estudio de diversos sectores industriales a los que la escoria Waelz pudiera ser destinada, se considera el sector cerámico como uno de los procesos susceptibles del empleo de este subproducto. Éste presenta la capacidad de incorporar múltiples materiales sin necesidad de realizar cambios relevantes en el proceso productivo y obteniendo un producto comercial de calidad en condiciones técnicas, económicas y medioambientales iguales o superiores a las actuales de acuerdo a la Ley de Prevención y Control Integrado de la Contaminación (IPPC).ABSTRACT: The recovery of Zn from steel dust by the Waelz process generates a by-product called Ferrosite or Waelz slag. Due to its high amounts of iron oxides, calcium oxides and silica, it could be considered a good candidate for valorisation as resource in other processes. The analysis of the industrial sectors in which the Waelz slag could be employed points out the ceramic field as a potential receptor. The ceramic sector has the capacity of admitting alternative materials without major process modifications. Besides, this allows the obtention of quality products in technical, economical and environmental conditions equal, or even superior, to those gathered in the Law on Integrated Pollution Prevention and Control (IPPC)