Mariya Marinova

• PhD, PEng
• Professor (Associate ) at Royal Military College of Canada

This paper gives an overview of development of the EU-bioeconomy, 2014–2020. The Vision of the new Circular Bio-based Economy, CBE is presented: Unlocking the full potential of all types of sustainably sourced biomass, crop residues, industrial side-streams, and wastes by transforming it into value-added products. The resulting product portfolio co...

A pre-hydrolysate is an aqueous stream obtained during the production of hardwood kraft dissolving pulp. It is rich in sugars and contains dissolved organic matters. The purpose of this study is to investigate the optimization of lignin recovery from wood pre-hydrolysates and to characterize the extracted lignin. The optimal conditions for lignin e...

The use of microorganisms is a promising option for an eco-efficient and successful conversion of hardwood hemicelluloses to biofuels. The focus of this work is the treatment of hemicellulosic pre-hydrolysate by flocculation, followed by simultaneous or separate detoxification with Ureibacillus thermosphaericus and Cupriavidus taiwanensis co-cultur...

Integrated forest biorefineries have been proposed as a viable option for the transformation of lignocellulosic biomass into a wide spectrum of profitable products for the pulp and paper industry. Hemicelluloses, a class of wood components can be extracted from a Kraft pulping process prior to chemical pulping and transformed by means of chemical a...

Butanol, a fuel with better characteristics than ethanol, can be produced via acetone–butanol–ethanol (ABE) fermentation using lignocellulosic biomass as a carbon source. However, many inhibitors present in the hydrolysate limit the yield of the fermentation process. In this work, a detoxification technology combining flocculation and biodetoxifica...

During dissolving pulp production, the extraction of hemicellulose and other organics from hardwood chips prior to the kraft pulping process can be performed using steam or hot water. The pre-hydrolysate from this step is rich in sugars and contains a considerable amount of lignin. It was estimated that the lignin content in this stream can be as h...

During the production of kraft dissolving pulp a pre-hydrolysate stream is generated prior to pulping. This pre-hydrolysate is a potential feedstock for the production of high value-added bioproducts. It contains a considerable amount of dissolved organics such as hemicelluloses, lignin and acetic acid. The purpose of this study was to investigate...

Prehydrolysate, a dilute solution consisting mainly of pentoses, hexoses, and lesser quantities of organic acids, furfural and phenolics, is generated in the Kraft dissolving pulp process. An obstacle facing the valorization of the solution in hemicellulose biorefineries, by conversion of the sugars into bioproducts such as furfural, is the low sug...

This paper focuses on the production of furfural from a simulated kraft dissolving pulp mill pre-hydrolysate solution that is rich in pentoses. Presently, this stream at the mill is mixed with the black liquor and then burned to recover some of the energy needed for the process. However, this pre-hydrolysate would have a higher potential if used as...

Phenolic compounds are important inhibitors of the microorganisms used in the Acetone-Butanol-Ethanol (ABE) fermentation. The degradation of phenolic compounds in a wood pre-hydrolysate, a potential substrate for the production of ABE, was studied in this article. First, physicochemical methods for detoxification such as nanofiltration and floccula...

Kraft prehydrolysate contains fermentable sugars and other organic compounds such as furans, phenolic compounds and acids, which are toxic to the fermentation microorganisms. In this work, bacteria-derived laccases were used to degrade key phenolic compounds. Firstly, the potential of degrading the key phenolic compounds in the prehydrolysate was d...

The life cycle assessment (LCA) methodology is increasingly used to ensure environmental sustainability of emerging biofuels. However, LCA studies are usually not performed at the process design stage, when it would be more efficient to identify and control environmental aspects. Moreover, the long-term economic profitability of biofuels depends on...

During kraft dissolving pulp production, the extraction of hemicellulose and other organics from hardwood chips prior to the pulping process is performed using hot water or steam. The pre-hydrolysate from this step is rich in sugars, lignin and acetic acid. Presently, this stream is added to black liquor and burned to produce energy for the process...

In this study, a new fermentation medium combining a flocculated hemicellulosic wood hydrolysate (FHWH), rich in carbohydrates, obtained from a pulp and paper mill and an alfalfa juice, rich in nitrogen was used to produce butanol by Clostridium acetobutylicum ATCC 842. It was demonstrated that pH control enhances solvent production. The culture co...

Confronted by a steady decline in the demand for commodity papers, the pulp and paper industry has undertaken intensive R&D efforts to identify and develop new non paper products that could be manufactured from the forest biomass. The components of wood that can be separated and converted into new non paper products are the cellulose, hemicellulose...

BACKGROUND: Spent sulfite liquor, a by-product obtained in the process of manufacturing dissolving pulp, contains 26% of sugars that can be valorized in order to obtain high value-added products by means of biorefinery processes. A technoeconomic assessment of three options, furfural, xylitol and ethanol, has been developed with the purpose of iden...

The conversion of agricultural and agro-industrial wastes and residues into a spectrum of marketable products and energy is of great importance to the environment and to sustainable development. The objective of this study is to assess the feasibility of using alfalfa juice to substitute or supplement expensive nutrients in an acetone-butanol-ethan...

The effects of mixing hydrodynamics on the particle and filtration properties of precipitated lignin from black liquor has been investigated. The hydrodynamics were varied in terms of turbulent shear rate and impeller flow pattern in the stirred tank. The precipitated lignin flocs were characterized in terms of particle size, size distribution, and...

The feasibility of using hardwood hemicellulosic pre-hydrolysate recovered from a dissolving pulping process for Acetone-Butanol-Ethanol (ABE) fermentation has been investigated. Dilutions and detoxification methods based on flocculation and nanofiltration were tested to determine the inhibitory concentration of phenolic compounds and to evaluate t...

The prehydrolysate stream from a Kraft dissolving pulp mill can be valorized by fermentation of the hemicellulosic sugars into biofuels or bioproducts, such as ethanol or butanol, instead of the typical practice of combustion to produce energy. An obstacle facing the use of Kraft hemicelluloses prehydrolysate for biofuels production is the low suga...

Hemicellulosic sugars from a Kraft dissolving pulp mill can be valorized through the integration of a biorefinery for furfural production. Furfural is a multipurpose platform chemical, with derivatives that can replace many organic compounds currently produced from fossil resources. A novel process for furfural production from biomass, with a Kraft...

The Green Integrated Forest Biorefinery (GIFBR), a new concept suitable for implementation in pulp and paper mills is characterized by low greenhouse gases emissions, reduced water consumption and production of effluents. Its fossil fuel consumption must be nil. Several challenges have to be addressed to develop a sustainable GIFBR facility. An imp...

The forest biomass is an abundant renewable resource from which biofuels can be derived. In the Kraft process the cellulose is extracted from the wood to form the paper pulp while the other organic components, primarily hemicelluloses and lignin, are burnt to produce steam. It is possible to divert part of the hemicelluloses or lignin to produce fu...

Incorporating a biorefinery unit to an operating Kraft pulping process has significant technological, economic and social advantages over the construction of a grassroot biorefinery. Also, the conversion of a Kraft mill from total pulp making to complete biorefinery can be done in a stepwise fashion and so give a company that envisages such transfo...

28 Lignin, which is currently burned in the Kraft mill recovery boiler, can be recovered and converted to a broad spectrum of bio-based products using the acid precipitation process. In this process, a part of the black liquor is extracted from the evaporator train and treated with CO 2 to precipitate the lignin. The precipitated lignin is washed w...

Water and thermal energy are extensively used in many chemical processes. Reducing the consumption of both utilities is important from both an economic and environmental point of view. A new method for water and energy optimization has been developed and is presented here. It consists of three steps: specification of the minimum water use that mini...

In recent years, the forest biorefinery has been identified and proposed as an opportunity for pulp and paper mills to improve their profitability. The implementation of biorefinery units will have an impact on the energy requirements of the receptor mill, and the energy consumption of the biorefinery should therefore be optimized before integratio...

For several years, the Canadian pulp and paper industry has been facing the worst crisis in its history. For a promising and sustainable future, the industry needs to develop and implement new profitable strategies. The objective of this review is to present the most promising options for the Canadian pulp and paper mills. Three options are conside...

For several years, the Canadian pulp and paper industry has been facing the worst crisis in its history. For a promising and sustainable future, the industry needs to develop and implement new profitable strategies. The objective of this review is to present the most promising options for the Canadian pulp and paper mills. Three options are conside...

A new systematic methodology has been developed to study interactions between water and energy in the kraft pulping process and has been applied to an operating mill. The methodology, which can be used to find appropriate strategies for water consumption reduction and which also considers their impacts on the thermal energy efficiency of the proces...

A methodology for the construction of computer simulations of chemical pulp mills suitable for conversion into integrated biorefineries has been proposed. A simulation of a dissolving pulp mill located in Eastern Canada has been developed using this methodology. The objective of the simulation is to supply data for energy and water studies and to a...

In Canada, the pulp and paper industry, a major contributor to the economy, is facing one of the most severe crises of its history. The biorefinery concept offers an opportunity to revitalize the industry by producing high-value chemicals and biofuels, by developing new technologies and by penetrating new markets. To become successful, the biorefin...

The development of integrated forest biorefineries is an attractive alternative for pulp and paper mills as they can increase their revenue by producing biofuels and chemicals in addition to their core products. However, the implementation of any biorefinery technology will alter the energy balance of the pulp mill. The purpose of this study was to...

The article investigates the feasibility of district heating in a small town adjacent to a Kraft pulp mill in eastern Canada. A detailed heat demand analysis is performed for all buildings using a geographical information system and archived data provided by the municipality. The study shows that the entire space heating requirement of the town can...

A systematic methodology is proposed to assist in the positioning of trigeneration units in industrial processes. It provides guidelines for the selection of heat sources and sinks which maximize the benefit derived from the trigeneration while respecting the process constraints and the operating requirements of the turbine and heat pump. The trige...

Résumé: La méthode de la double représentation est appliquée à l’analyse énergétique du département des évaporateurs dans une usine de pâtes kraft. La demande en énergie est représentée sous deux perspectives, thermodynamique et technologique, qui permettent d’identifier les opportunités de réduction des coûts énergétiques liés au fonctionnement de...

The effect of the modifier 1-decanol on the extraction of tartaric acid by the extractants tri-n-octylamine (TOA), quaternary ammonium chloride (Aliquat 336), or their mixture in the diluent n-dodecane was studied at different pH values. The effect of the modifier was examined as a function of the initial pH value of the aqueous solution for the th...

A study of the possibilities for separating tartaric and lactic acids from winery wastewaters was conducted. Some principal extractants were tested. The organic phase containing TBP, dodecane or TOA, 1-decanol, dodecane permits a selective extraction of one of the acids. The distribution coefficients of both acids with solution of tertiary amine, m...

A novel method for the extraction of lactic acid by means of a modified extractant is proposed. A quaternary ammonium salt (Aliquat 336), dissolved in 1-decanol and n-dodecane, is treated successively with different concentrations of ammonium carbonate for replacement of the chloride anion with a carbonate one. The effects of the initial lactic aci...

Equilibrium studies on the extraction of lactic acid by means of a mixed extractant (a mixture of tri-n-octylamine and Aliquat 336 in decanol) are carried out. Different ratios between the two extractants are investigated, and the obtained results are compared with those using the individual extractants. The effect of the initial pH of the aqueous...