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To evaluate the effect of brown-rot fungi Oligoporus placenta and earthworm Eisenia fetida on decomposition of paper mill sludge, the paper mill sludge was mixed with cow dung in 0, 25, 50, 75, and 100% proportions and changes in physicochemical quality of waste mixtures was carried out for 28 days. All waste mixtures were treated with: Setup-I (E. fetida), Setup-II (O. placenta) and, Setup-III (E. fetida + O. placenta). A decrease in total organic carbon, C/N ratio and cellulose but an increase in total kjeldhal nitrogen, total phosphorus, total potassium and pH was recorded. The paper mill sludge in 50–75% proportion in feedstock showed the better results and rate of mineralisation were in order: Setup-III > Setup-I > Setup-II. The proportion of CD has direct role in waste mineralisation. The microbial population (bacterial, fungal and actinomycetes) and earthworm biomass were also high in Setup-III, suggesting the influence of brown-rot fungi on paper mill sludge humification. Results indicate that fungal inoculate in vermicomposting was effective in decomposing cellulose-rich industrial sludge.

The global demand for bio-plastic particularly polyhydroxyalkanoate (PHA) have been increased in the last few decades as a substitute of petrochemical-based plastic. Utilization of waste paper, the primary constituent of municipal solid waste (MSW), as a carbon source for polyhydroxybutyrate (PHB) production is not only an alternative, environmental friendly route of waste management but also helps to valorize the waste. In this study, hydrogen peroxide pretreated waste paper saccharification has been optimized using central composite design (CCD). The maximum hydrolysis (88.18%) occurred at paper loading 5.0 g/L, agitation 242 rpm, working volume 20%, cellulase 49.82 U/g, β-glucosidase 20.9 U/g and hemicellulase 29.5 U/g. PHB synthesis and biomass accumulation by xylose-utilizing Burkholderia sacchari using waste paper hydrolysate were studied using different nitrogen sources and carbon to nitrogen (C/N) ratios. Maximum PHB and dry cell weight (DCW) occurred with ammonium sulfate and a C/N ratio of 20. The highest biomass (3.63 g/L), the maximum PHB accumulation (44.2%) and the maximum reducing sugar utilization (92.1%) were observed after 48 h of cultivation using diluted hydrolysate. The physicochemical properties of the extracted PHB were compatible with the standard PHB. Hence, the waste paper could be exploited as a renewable feedstock for the sustainable production of PHB.

It is necessary to preserve rumen fluid for transport from slaughterhouses to the pretreatment facilities for use in treating lignocellulosic biomass. In this study, we investigated how the preservation of rumen fluid at various temperatures affects its use in hydrolysis of waste paper. Rumen fluid was preserved anaerobically at 4, 20, and 35 °C for 7 days. The number of protozoa and fibrolytic enzyme activity after preservation at 4 °C were significantly higher than that after preservation at either 20 or 35 °C. Waste paper was subsequently treated with preserved rumen fluid at 37 °C for 48 h. Preservation at 20 °C remarkedly decreased the hydrolysis of waste paper. Xylanase activity in rumen fluid preserved at 35 °C increased during the treatment, which enhanced the solubilization of waste paper as comparable to the control and preservation at 4 °C. Pretreatment of waste paper with rumen fluid preserved at 4 °C showed that the fluid retained high fibrolytic activity, and reduced the loss of organic carbon as substrate for methanogens. Our results suggest that preservation of rumen fluid at 4 °C is most suitable for efficient pretreatment and methane fermentation of waste paper.

The Swedish climate policy framework requires national GHG emissions to reach net zero by 2045 and become negative thereafter. Bioenergy carbon capture and storage (BECCS) has been identified as a possible main contributor to reach these targets by providing negative emissions – both to offset residual emissions in “hard-to-abate” sectors and to achieve net negative emissions. The pulp and paper industry is the single largest consumer of biomass in Sweden with many large point sources of biogenic CO2 emissions which could potentially be captured. This work investigates the biomass supply required for large scale implementation of BECCS in the pulp and paper industry. Regional biomass supply possibilities are evaluated by choosing four pulp and paper mills located in different parts of Sweden. The results show that regional biomass supply can limit the possibilities for BECCS implementation in regions with high competition for biomass. In regions with low competition and high availability of biomass regional biomass supply can potentially assist CCS implementation on biogenic sources. It is concluded that for a densely populated and industrialized region with high use of logging residues in the heating sector, in this work represented by southern Sweden where two of the studied mills are located, the possibility to increase regional supply of logging residues to fuel the capture process while maintaining mill production output, is limited due to competition for the same assortment of biomass from the energy sector (combined heat and power in district heating systems).

Paper industry wastewater is the significant source of water and soil contamination due to various unknown residual organic pollutants directly discharged into the environment without proper treatment. Therefore, the study has focused on the detection of residual organic pollutants (N-(1,2,2,2-tetrachloroethyl) trimethylacetamide, octadecane, 1-iodo, Oleic acid, trimethylsilyl ester, eicosane; hexadecane, 2-methyl-; octadecane, docosane; tricosane) from paper industry wastewater sources showed endocrine-disrupting compounds and their toxicity. This experiment were carried out the effect of paper mill sludge amendments with garden soil (25%, 50%, 75%, and 100%) and garden soil was utilized as a control in a pot experiment. This study revealed the growth parameters of Triticum aestivum in seeds germination percentage and germination index values decreased with rising in sludge concentration. Further, soil amended with 25% paper industry sludge slightly reduced the growth in root length, shoot length, biomass, photosynthetic and 50% sludge amended soil had variable effects on the root, shoot, and photosynthetic pigment of T. aestivum. Moreover, the toxicity of paper industry wastewater on tubifex-tubifex worms after 48 h of exposure (>50% concentration), worms showed various changes such as movement; haemoglobin content disappeared, cell bursting, and the back of the body became white with body disintegration at the lethal concentrations of paper industry wastewater. This article has revealed that the toxicity of the organic pollutants in the terrestrial and aquatic life due to paper industry wastewater there is needed to treat adequately prior to discharge.

Contaminated water contains various types of pollutants, the removal of which requires two or more technologies. It is imperative but challenging to develop water purifier for simultaneous removal of multiple pollutants for the sake of easy operation, low cost, and etc. Previously reported multifunctional purifiers are normally nanoparticles which require caution during use. Here, we describe a design of paper-like multifunctional purifier, which has biomass-based structure by grafting polyethylenimine derived quaternary ammonium compounds onto three-dimensional bacterial cellulose substrate. Compared to similar materials reported previously, our product exhibited strikingly higher adsorption capacities towards various metal ions including Pb2+, Cu2+, and Cr6+, anionic organic dyes including congo red, methyl orange and methyl red, and excellent disinfection efficiency towards both Gram-negative and Gram-positive bacteria. Remarkably, this purifier also demonstrated effective removal of the three contaminative species simultaneously from both simulated and local polluted water. With more virtues of superior reusability and extreme handy convenience, we hope our molecular design could inspire further efforts on the rational construction of multifunctional water purifier with easy operation. We reckon our material to have strong potential for the possible use in water treatment, especially in regions that are short of environmental infrastructures.

Energy recovery from small and medium scale waste thermal treatment facilities in the municipalities of Japan is challenging, owing to low power generation efficiency and high economic demands. Gas Engine (GE) generation is considered an efficient resource utilization method in these facilities. In this study, new and consistent feedstock, Refuse Paper and Plastic Fuel (RPF), and wood pellets were tested in an air-blown Fluidized Bed Gasifier (FBG) for syngas utilization in a GE. With temperatures ranging from 700 to 940 °C and varying Equivalence Ratios (ER) of 0.3–0.5, some of the most important product gas characteristics were analyzed, including the Lower Heating Value (LHV) and tar concentration levels. Gas composition results revealed that the concentration tendencies varied for the product gases CO, H2, and hydrocarbons, depending on the feedstock type, whereas the same tendencies were observed for CH4 and tar concentrations. Through the ER range, the LHV of product gas for RPF and wood pellets was 3.4–5.9 MJ/Nm3. Tar concentrations decreased to 2.5–14.0 g/Nm3-dry as the ER was raised. The optimal ER for LHV performance in GE generation was approximately 0.4 for RPF and wood pellets, and remaining tar concentrations were about 5.0 g/Nm3-dry at the gasifier exit.

In remote areas, such as India, Africa and Southeast Asia, typically not connected to the natural gas distribution network, tissue paper production is currently carried out using a Yankee cylinder and two hot air hoods heated with saturated steam produced in conventional boilers. In this way the drying air is heated at medium temperature, around 160-180 °C, with consequent low levels of dried paper production. In this context, the present study intends to evaluate the technical and economic feasibility of using a wood biomass fixed bed downdraft gasification plant for the production of syngas to be used as fuel in gas hoods, in order to reach high drying temperatures (around 500 °C), comparable with those of the current modern hoods powered with natural gas. Using previously developed calculation codes, an evaluation of energy performance of the paper drying system and of the gasification plant has been performed. The present study also evaluates the possibility of applying a CHP plant, powered by biomass, for the production of steam and electric, this last obtained adopting a steam turbine, thus covering all the electrical and thermal needs of the paper mill. Results show that, for a paper mill with a production of about 80 t/day of paper, two gasification reactors with a thermal output of about 1.95 MWt, and a consumption of dry biomass of 0.86 t/h, are required. For the steam system, the net electric power needed to meet the needs of the paper mill is about 3100 kW with a consumption of 4.72 t/h of moist biomass and a net efficiency of 23.9 %.

Waste paper, a major fraction of municipal solid waste, has a potential to serve as renewable feedstock for the biorefineries of fuels, chemicals and materials due to rich in cellulose and abundant at low cost. This study evaluates the possibility of waste office paper (WOP) to serve as a potential feedstock for the biorefinery production of poly (3-hydroxybutyrate). In this study, the WOP was pretreated, enzymatically saccharified and the hydrolysate was used for PHB production. The hydrolysate mainly consists of glucose (22.70 g/L) and xylose (1.78 g/L) and the corresponding sugar yield was about 816 mg/g. Ammonium sulphate and C/N ratio 20 were identified as most favorable for high yield of PHB. The batch fermentation of Cupriavidus necator using the pretreated WOP hydrolysate resulted in cell biomass, PHB production and PHB content of 7.74 g/L, 4.45 g/L and 57.52%, respectively. The volumetric productivity and yield achieved were 0.061 g/L/h and 0.210 g/g sugar, respectively. The results suggested that WOP could be a potential alternative feedstock for the biorefinery production of bioplastics.

The present study investigates the effect on methane production from waste paper when co-digested with macroalgal biomass. Both feedstocks were previously mechanically pretreated to reduce their particle size. The study was planned according two factors: the feedstock to inoculum (F/I) ratio and the waste paper to macroalgae (WP/MA) ratio. The F/I ratios checked were 0.2, 0.3 and 0.4 and the WP/MA ratios were 0:100, 25:75, 50:50, 75:25 and 100:0. The highest methane yield (386 L kg−1 VSadded) was achieved at an F/I ratio of 0.2 and a WP/MA ratio of 50:50. A biodegradability index of 0.87 obtained in this study indicates complete conversion of feedstock at an optimum C/N ratio of 26. Synergistic effect was found for WP/MA 25:75, 50:50 and 75:25 mixing ratios compared with the substrates mono-digestion.

This study mainly investigated the feasibility of utilizing cellulase to enhance waste activated sludge (WAS) and paper waste (PW) co-fermentation for the generation of volatile fatty acids (VFAs). The introduction of cellulase effectively enhanced the co-fermentation efficiency, and the maximum VFAs generation reached 3014 mg COD/L with 60 mg cellulase/g TSS while it was 1512 mg COD/L in the control reactor. The presence of cellulase evidently improved the concentration of soluble bioavailable substrates (e.g., carbohydrates and proteins) via inducing the EPS disintegration and PW disruption. More importantly, the functional anaerobes (i.e., Macellibacteroides and Bacteroides) and the microbial activities (i.e., ATP, key acid-forming enzymes, and genetic expressions) that related with the VFAs biosynthesis were enriched and enhanced due to the stimulation of cellulase, contributing to the ultimate VFAs promotion. This study provided a novel strategy to recover valuable products from waste biomass with constructive mechanistic exploration.

International audience; Hemicellulose materials are arguably the second most abundant renewable component of lignocellulosic biomass after cellulose. They are relatively under-utilized hetero-polysaccharides present in lignocellulosic biomass. In this research an alkaline treatment was optimized for extraction of polymeric hemicellulose from fully bleached hardwood pulp (B-HWP) and partially delignified switchgrass (SWG). The hemicellulose extracted from B-HWP was relatively pure with zero percent lignin and 89.5% xylose content whereas the partially delignified SWG hemicellulose contained about 6-3% lignin and 72–82% xylose, depending on the NaOH concentration during extraction (3–17% NaOH solution). A maximum molecular weight of SWG hemicellulose of 64,300 g/mol was achieved for the 10% NaOH solution extraction, whereas the MW of B-HWP hemicellulose at 10% NaOH solution extraction was lower at 49,200 g/mol. We have demonstrated that the residual lignin in SWG hemicellulose lowered the system Tg and this might be utilized as a way to increase the applications of hemicellulose in high value biomaterials. Furthermore, the hemicellulose could be crosslinked with zirconium to develop a water resistant gel for coating or adhesive applications. Our results showed that the loading stress required to break an hemicellulose based adhesive connection between two paper surfaces was 0.89, 2.02, 2.75, 3.46, and 3.11 (MPa) for 2, 4, 6, 8 and 10% AZC samples, indicating that up to about 8% AZC crosslinker in the hemicellulose increases the adhesive behavior of the material.

As a kind of industrial hazardous solid waste, paper mill sludge (PMS) was hard to treated by conventional process because of its high moisture, high organic content and and high environmental risk. The hydrothermal liquefaction (HTL) shows excellent potential for the conversion to a wide variety of organic matter with high water contents including various kinds sludge into fuels or value-added chemicals. In this paper, the liquefaction potential for PMS under different reaction temperatures were investigated, and the products were classified into several main components based on the results of GC-MS. The results showed that the highest yield of bio-oil was 44 % (wt/wt dry PMS without ash) at 340 °C with simply compound composition. And the bio-oil product has above 26 % long chain hydrocarbon and 22 % cycloketones. It has potential for conversion to biomass platform compounds. It can be used as bio-fuel for heat recovery of alkali recovery system of paper mill. So, adjusting different reaction temperatures of HTL, the properties of products can meet the different requirements for platform chemical and/or bio-oil fuel.

A two-stage thermophilic hydrogen fermentation and mesophilic methane production from paper sludge was successfully explored. The maximum hydrogen and methane potential were 0.165 L/g VS and 0.376 L/g CODeffluent, respectively with Clostridium thermocellum augmentation. 63 L of hydrogen and 122 L of methane were recovered from 1 kg Paper sludge (PS, dry weight) with an energy yield of 4.5 MJ/kg PS, 50% higher compared to the single-stage anaerobic digestion (94 L CH4, 3.0 MJ/kg PS). The bacterial community of second-stage process was dominated by genus Propionispira, Mesotoga and Aminobecterium with stability, whereas the bacterial structure in single-stage process presented dynamic changes where genus Acetivibrio and Fibrobacter played an indispensable role. However, Genus Methanosaeta, Methanosarcina, Methanobacterium and Methanospirillum existed stably and predominantly in the archaeal community of single-stage and second-stage processes. The present study suggests the potential application of the established two-stage process in valorization of low-value waste biomass.

Herein, we demonstrate a microwave-assisted chemical reduction technique to exfoliate a few layers of graphene from the natural waste material, ‘coconut shell’. The microwave irradiation coconut shell is subjected to structural, morphological and functional groups characterization methods including SEM, Raman, FTIR and XPS spectroscopic analyses. The formation of biomass reduced graphene (BRG) has been confirmed through Raman and FTIR spectroscopic analyzes with the presence of D, G and 2D and other functional spectral bands, respectively. The surface topography of the BRG exhibits two-dimensional mat structures with wrinkle topography, imaged by electron microscopic techniques. The metallic behaviour of the BRG is evaluated by band structure calculation using density functional theory. The synthesized nanostructure has been evaluated for exhaled diabetic breath sensing application by fabricating sensor device on the paper-based substrate by roll-to-roll coating technique. The BRG sensor exhibited enhanced sensing response at a very lower concentration of diabetic biomarker with long term stability and rapid response/recovery time of 1.11 s/41.25 s, respectively. Based on our findings, the microwave-assisted BRG is a potential candidate for fabricating highly scalable, inherently safe, economically viable and excellent sensing performance to detect exhaled diabetic breath at room temperature.

The biorefinery design has attracted interest from the industry and scientific community due to its main role in a future transition to a sustainable bioeconomy. This paper provides a critical review of the integration of biorefinery concepts in the pulp and paper industry, focusing on gasification-based biorefineries, including technological and commercial drivers and barriers, and biorefinery general opportunities and challenges. The pulp and paper industry is commonly recognized as highly suitable to integrate biorefinery concepts. For this purpose, various integrable biorefinery designs composed of distinct conversion processes are proposed in the literature. However, key technologies and biorefinery concepts must firstly be improved and proven at a market level to increase stakeholders confidence. Gasification can be a driving force for this integration and efficient replacement of natural gas by producer gas in burners is the first and most immediate step. Nonetheless, drawbacks associated with the contaminants present in the producer gas (e.g., tars) must be addressed. Research rarely focus on this first step and is more centered on sophisticated gasification applications (e.g., methanol synthesis), without considering associated technological and commercial barriers. Furthermore, supporting policies are generally required to make the integration of biomass gasification technologies in the pulp and paper industry profitable and to avoid the interruption of operation of fully functioning large-scale gasification plants.

Growth properties, oxidation-reduction potential kinetics and hydrogen production of Escherichia coli BW25113 parental strain (PS) and hydrogenase (Hyd)-negative mutants were investigated after fermentative growth using office paper waste and cardboard (PW) hydrolysate (PWH). PWH was obtained by using dilute acid method in a steam sterilizer for 1 h, 121 °C. Optimal conditions for bacterial growth and H2 production were identified (PWH concentrations, pH 7.5). Recording of redox potential using a platinum electrode revealed a drop to −500 ± 10 mV, with a H2 yield of ~1.45 mmol H2 L−1 after 4 h of growth using PWH resulted in the formation of 0.20 ± 0.02 g bacterial cell dry weight L−1. Bacterial biomass formation was stimulated ~3-fold upon addition of 0.5% yeast extract, and H2 production started early - at the beginning of the exponential phase. Moreover, mutants lacking Hyd-1 and Hyd-2 significantly enhanced H2 production. The findings would be beneficial for the development of H2 production biotechnology using cheap solid waste materials.

Paper mill sludge (PMS) was assessed as cheap renewable lignocellulosic biomass for lipid production by the oleaginous yeast Cryptococcus vishniaccii (MTCC 232). The sonicated paper mill sludge extract (PMSE) exhibited enhanced lipid yield and lipid content 7.8±0.57g/l, 53.40% in comparison to 5.5±0.8g/l, 40.44% glucose synthetic medium, respectively. The accumulated triglycerides (TAG) inside the lipid droplets (LDs) were converted to biodiesel by transesterification and thoroughly characterized using GC-MS technique. The fatty acid methyl ester (FAME) profile obtained reveals elevated content of oleic acid followed by palmitic acid, linoleic acid and stearic acid with improved oxidative stability related to biodiesel quality.

Mixed sludge from a pulp and paper mill was hydrothermally carbonized at 180–260 °C for 0.5–5 h with the use of HCl or NaOH for determining the effect of acid and base additions during sludge carbonization. Based on the results carbonization was mainly governed by dehydration, depolymerization and decarboxylation of sludge components. Additive type had a statistically significant effect on hydrochar carbon content and carbon and energy yield, of which especially energy yield increased through the use of HCl. The theoretical energy efficiencies of carbonization increased with decreasing reaction temperature, retention time and the use of HCl and suggested that the energy requirement could be covered by the energy content of attained hydrochar. The BOD5/COD-ratios of analyzed liquid samples indicated that the dissolved organic components could be treated by conventional biological methods.

Plastic film (PF) is a common soil mulching material used worldwide in crop production. In recent years there is an increasing demand for reducing the use of PF because of potential environmental- and ecological-risks. Although biodegradable paper (BP) and bio-based film (BB) have been used as alternatives to PF, little information is available regarding their efficiency in summer crop production, which is often restricted by the combination of heat stress and drought stress. To meet this need, PF (silver-gray plastic film made from polyethylene), BP (biodegradable paper made from plant straw) and BB (bio-based film made from plant straw combined with decomposed coal) were used as soil mulching materials to investigate their influence on soil properties (temperature, moisture, pH, electricity conductivity (EC), nutrients and enzymes), plant growth (root morphology, the relative growth rate (RGR), plant biomass and the root/shoot ratio), fruit yield and fruit quality. The un-mulched soil served as control. The trial was conducted in a five-year-old commercial greenhouse located in Helan county, Ningxia, China, with the mean air temperatures of about 32 °C and 31 °C during the summer season in 2016 and 2017, respectively. In general, although PF mulching increased soil moisture, it increased soil temperature, pH and EC and decreased available P, resulting in the reduction of plant growth (root length and diameter, the RGRs of plant height and leaf area, and shoot and root biomass) and fruit yield. The BB mulching decreased soil temperature, however, it decreased soil moisture and invertase and increased soil EC, leading to reduced root growth (root diameter and biomass, and the root/shoot ratio). The BP mulching not only decreased soil temperature, but also increased soil moisture. As a result, it showed several advantages such as decreasing soil EC, increasing soil enzyme activities, improving plant growth (root length, the RGRs of plant height and leaf area, plant biomass and the root/shoot ratio) and increasing fruit yield. Moreover, the fruit quality was partly improved by BP mulching due to reduced nitrate but increased vitamin C. Our results infer that BP was a potential mulching material that could be used for summer tomato production.

The aim of the study was to grow microalgae on mixed municipal and industrial wastewater to simultaneously treat the wastewater and produce biomass and lipids. All algal strains grew in all wastewater mixtures; however, Selenastrum minutum had the highest biomass and lipids yields, up to 37% of the dry matter. Nitrogen and phosphorus removal were high and followed a similar trend in all three strains. Ammonium was reduced from 96% to 99%; this reduction was due to algal growth and not to stripping to the atmosphere, as confirmed by the amount of nitrogen in the dry algal biomass. Phosphate was reduced from 91% to 99%. In all strains used the lipid content was negatively correlated to the nitrogen concentration in the algal biomass. Mixtures of pulp and paper wastewater with municipal and dairy wastewater have great potential to grow algae for biomass and lipid production together with effective wastewater treatment.

Biomass is a renewable energy and had been recognized as a promising feedstock for producing bio-fuels. In this work, pyrolysis of black wattle residues was investigated with the aim to study the product distribution and their chemical composition and predicting the optimal condition for maximized bio-oil especially aromatics content by using a two level factorial design of experiment. The pyrolysis were performed at temperature of 380 – 580 oC, Under screw feeder carried the biomass residues and weight of dolomite as catalyst of 1-5 wt% inside pyrolyzer with nitrogen gases flow rate of 20 to 80 cm3/min The detention time was controlled by reactor screw feeder at feeding rate of 120 to 240 rpm. Based on the analysis from a design-expert program to determine the appropriated condition of experiment was 515.18 oC, 120.01 rpm of feed rate and 20.00 cm3/min of nitrogen flow rate using 5.00wt% of dolomite catalyst. The elemental and physicochemistry analysis of bio-oil were determined, the chemical composition also investigated using gas chromatography-mass spectrometry and 1H NMR. The composition of bio-oil mainly oxygenated compound with high molecular weight and phenol. The results show that the biomass residual can be considered as a potential alternative fuels and relevant to valuable chemical feedstock.

Levoglucosan is used as a tracer of biomass burning; however, its determination often requires expensive analytical techniques. Therefore, this study describes the development of an inexpensive and useful method using paper-based analytical devices (PADs) to determine levoglucosan based on colorimetric measurements. The color intensities were correlated with the analytical concentrations and presented linear behavior in the range from 0 to 64.8 μg mL−1. The achieved limits of detection and quantification were 2 and 6 μg mL−1, respectively. The conversion rate of levoglucosan into glucose was 81 ± 8% and the average recovery was 105 ± 9%. Moreover, the method presented selectivity for levoglucosan, showing variation in colorimetric signal intensity lower than 8% in the presence of other saccharides (xylose, glucose, galactose, maltose, mannose, arabinose, and fructose). The accuracy of the method was confirmed by comparison with gas chromatography-mass spectrometry. The proposed method was explored to determine levoglucosan in samples of atmospheric particulate matter collected in Goiania city (Brazil) and the values ranged from 0.08 to 1.10 μg m−3, showing the high impact of the biomass burning to the particulate matter in the region's atmosphere. The method was also used to detect levoglucosan in rainwater samples. Therefore, the use of PADs can simplify fieldwork involving the determination of levoglucosan in atmospheric particulate matter.

Remediation of engineered-nanomaterials is an up-coming major environmental concern. This study demonstrates adsorptive-remediation of cobalt oxide nanoparticles (CoO NPs) from the water. The α-cellulose-fibers were extracted from waste-paper biomass (WP-αCFs) and magnetized with Fe3O4 NPs (M-WP-αCFs). The XRD, FT-IR, and TGA were performed for detailed characterization of the newly developed bioadsorbent. The M-WP-αCFs was then applied for adsorptive remediation of CoO NPs. The adsorptive kinetics of CoO NPs adsorption onto the M-WP-αCFs reveals the pseudo-second-order model. The various adsorption isotherm studies revealed Langmuir is a best-fit isotherm. A prominently high adsorption capacity qm (1567 mg/g) corroborated extraordinary adsorptive potential of M-WP-αCFs. Furthermore, CoO NPs were adsorbed onto M-WP-αCFs were analyzed by the XPS, VSM, and TEM. Therefore, this study gave rise WP biomass extracted and rapidly-separable nano-biocomposite of ‘M-WP-αCFs’ with a high-capacity for CoO NPs remediation and can be further applied in remediation of several other engineered-nanomaterials.

Soil algal bioassays have been limited by their inability to evaluate several toxic endpoints because it is difficult to collect pure soil algae growing on and beneath the soil surface. This study describes the extension of a previously developed paper-disc method for analyzing soil toxicity to algae. The method can be used in conjunction with flow cytometric analysis and facilitates the assessment of previously proposed toxicity endpoints, such as the growth zone, biomass, and photosynthetic activity. We assessed the applicability of this paper-disc soil method using the green algae Chlamydomonas reinhardtii and Pseudokirchneriella subcapitata exposed to nickel-contaminated soil; examined cell sizes, cell granularity, enzyme activity, and oxidative stress as new toxicity endpoints using flow cytometry; and identified morphological changes in green algae assayed. The results showed that, used in conjunction with flow cytometry, the extended paper-disc soil method is sufficiently sensitive to detect decreases in cell granularity in C. reinhardtii and esterase activity in P. subcapitata. The method also revealed decreases in growth zone, biomass, and electron transfer from the reaction center to the quinone pool. Collectively, the results of this study indicate that soil algal bioassays using nonspecific algae can be used to assess soil quality, to derive several toxicity endpoints for individual cells, and to evaluate previously established flow cytometric toxicity endpoints.

A novel integrated thermophilic submerged aerobic membrane bioreactor (TSAMBR) and electrochemical oxidation (EO) technology was developed for thermomechanical pulping pressate treatment with the aim of system closure. The TSAMBR was able to achieve a chemical oxygen demand (COD) removal efficiency of 88.6 ± 1.9-92.3 ± 0.7% under the organic loading rate of 2.76 ± 0.13-3.98 ± 0.23 kg COD/(m(3) d). An optimal hydraulic retention time (HRT) of 1.1 ± 0.1d was identified for COD removal. Cake formation was identified as the dominant mechanism of membrane fouling. The EO of the TSAMBR permeate was performed using a Ti/SnO(2)-Sb(2)O(5)-IrO(2) electrode. After 6-h EO, a complete decolourization was achieved and the COD removal efficiency was increased to 96.2 ± 1.2-98.2 ± 0.3%. The high-quality effluent produced by the TSAMBR-EO system can be reused as process water for system closure in pulp and paper mill.

This study evaluates acid pretreated waste paper hydrolyzate as feedstock for bioethanol production. The presence of 70.12 ± 4.88% carbohydrates (holocellulose) makes waste paper a prospective and renewable biomass for bioethanol production. The waste paper was found to contain α-cellulose (61.5 ± 3.49%), pentosans (7.42 ± 0.36%), lignin (16.33 ± 0.96%), ash (12.50 ± 0.33%) and moisture (8.28 ± 0.63%). Conditions for the dilute acid pretreatment of waste paper were optimized by varying solid/liquid ratio 1:8–1:14 (w/v), reaction time 01–06 h, and sulfuric acid concentration 0.005–1.00 N at 120 °C in an autoclave. The conditions optimized for acid hydrolysis of waste paper were 0.50 N H 2 SO 4 at 120 °C for 02 h reaction time keeping biomass:acid ratio 1:10 (w/v) for recovery of reducing sugars from waste paper hydrolyzate. Fermentation of acid hydrolyzate of waste paper with Pichia stipitis under optimum condition resulted in ethanol production 3.73 ± 0.16 g/l with 77.54 ± 4.47% of fermentation efficiency.

A new method, microwave pyrolysis, has been investigated to dispose the paper mill sludge. Microwave pyrolysis is a new fast pyrolysis technology for biomass. The effects of various different factors on paper mill sludge’s microwave pyrolysis were mainly discussed. The results showed that the mass of the paper mill sludge reduced very rapidly within the first 6 min and then flattened out with the microwave reaction time increasing; The greater the microwave power was, the faster the sludge’s pyrolysis and the more the smell and concentration of diesel smoke was; The pyrolysis performance was better when the dosage of the paper mill sludge was increased and of 5% NaOH was added as microwave absorbers; Under CO2 atmosphere, the pyrolysis performance was the best when of 5% NaOH was added, while under N2 atmosphere, the pyrolysis performance was the best when of 5% ZnCl2 was added.

This study investigated the feasibility of the enhanced efficiency of energy yields in the catalytic gasification processes of paper-reject sludge. The experiments were conducted by controlling the temperatures that ranged from 600 °C to 900 °C with the addition of the mineral catalyst (calcium oxide, CaO) with a ratio that ranged between 10 percent and 20 percent by weight. According to the experimental results, increasing gasification temperatures will enhance the lower heating value (LHV) of syngas in the gasification of paper-reject sludge. The LHV of syngas increased from 10.6 MJ/Nm 3 to 21.1 MJ/Nm 3 with increased temperatures from 600 °C to 900 °C. The energy density of syngas was also increased from 1.13 to 4.56, as gasification temperature operated between 600 °C and 900 °C. This implied that the energy utilization of syngas, produced by gasification, could increase approximately four times the energy content of paper-reject sludge. Besides this, the energy yield efficiency in gasification will be enhanced by the tested mineral catalyst. In the case of gasification temperatures operating from 600 °C to 900 °C, the LHV of syngas increased significantly from 13.04 MJ/Nm 3 to 21.52 MJ/Nm 3 by the tested mineral catalyst. Meanwhile, the results of the energy density as well as the carbon conversion rate in catalytic gasification indicated that the results were 2.8–4.59 and above 95%, respectively. The experimental results of this research confirm that it is possible to improve the efficiency of tar reduction and energy yields using a tested mineral catalyst and can promote the potential for renewable energy in the application of paper-reject sludge.

Supercritical water gasification (SCWG) is a method by which biomass can be converted into a hydrogen-rich gas product. Wet industrial waste streams, which contain both organic and inorganic material, are well suited for treatment by SCWG. In this study, the gasification of two streams of biomass resulting from the pulp and paper industry, black liquor and paper sludge, has been investigated. The purpose is to convert these to useful products, both gaseous and solids, which can be used either in the papermaking process or in external applications. Simple compounds, such as glucose, have been fully gasified in SCWG, but gasification of more complex compounds, such as biomass and waste, have not reached as high conversions. The investigated paper sludge was not easily gasified. Improving gasification results with catalysts is an option and the use of alkali salts for this purpose was studied. The relationship between alkali concentration, temperature, and gasification yields was studied with the addition of KOH, K2CO3, NaOH and black liquor to the paper sludge. Addition of black liquor to the paper sludge resulted in similarly enhancing effects as when the alkali salts were added, which made it possible to raise the dry matter content and gasification yield without expensive additives.

The effect of waste paper on biogas yield produced by co-digesting fixed amount of cow dung and water hyacinth in five digesters A–E was studied at room temperature. Waste paper was observed to improve biogas yield in digesters B–E with digester A acting as the control. However, as the amount of waste paper increased the biogas yield was observed to decrease. Kinetic model based on first order kinetic was derived to estimate the maximum, ultimate, biogas yield and also the ultimate methane yield from these biomass mixtures. The maximum biogas yield estimated using this model for digesters B–E were 0.282, 0.262, 0.233, and 0.217 lg −1 VS fed with goodness of fit ( R 2 ) of 0.995, 0.99, 0.889, and 0.925 respectively, which were obtained by fitting the experimental biogas yield ( y t ) against (exp( kt )−1)/exp( kt ). The ultimate biogas and methane yield at very low batch solid load were extrapolated to be 0.34 and 0.204 lg −1 VS fed respectively. In essence, the addition of waste paper in the co-digestion of cow dung and water hyacinth can be a feasible means of improving biogas yield and also alternative means of recycling waste paper. Furthermore, the kinetic model developed can compliment other models used in anaerobic digestion of agricultural and solid waste.

The performance of four species of earthworm––Eudrilus eugeniae, Kinberg, Drawida willsi Michaelsen, Lampito mauritii, Kinberg and Perionyx excavatus, Perrier––born and grown in vermireactors fed with paper waste was studied over six months, in terms of vermicast output per unit feed, production of offspring, and increase in worm zoomass. These were compared with the performance of the previous generation which had been raised to adulthood on cowdung as principal feed before shifting them to vermireactors operating on cowdung-spiked paper waste. The results indicated that except with D. willsi of which the second generation performed only a shade better than the first, there was significant improvement in vermicast output, animal growth, and reproduction in the second generation compared to the first. The results indicated that cowdung-spiked paper waste can be an adequate food for successive generations of earthworms and that reactors can be operated indefinitely on this feed. The results also indicated that the earthworm generations born and raised in vermireactors operated on this feed become better vermiconverters of this feed than the parent earthworms.

Gluconic acid production was investigated using an enzymatic hydrolysate of waste office automation paper in a culture of Aspergillus niger. In repeated batch cultures using flasks, saccharified solution medium (SM) did not show any inhibitory effects on gluconic acid production compared to glucose medium (GM). The average gluconic acid yields were 92% (SM) and 80% (GM). In repeated batch cultures using SM in a turbine blade reactor (TBR), the gluconic acid yields were 60% (SM) and 67% (GM) with 80-100 g/l of gluconic acid. When pure oxygen was supplied the production rate increased to four times higher than when supplying air. Remarkable differences in the morphology of A. niger and dry cell weight between SM and GM were observed. The difference in morphology may have caused a reduction of oxygen transfer, resulting in a decrease in gluconic acid production rate in SM.

Land restoration at a former landfill site, Bidston Moss, NW England, has involved heavy applications of paper mill sludge (PMS), a byproduct of paper recycling. The development of earthworm communities at the site has been assisted by earthworm inoculation. Initially low numbers of epigeic species were present, but as the restoration has progressed since 1996 a substantial number, biomass and diversity of earthworms has become established, including a variety of ecological types. In some areas there is substantial surface casting. Cast colour indicates selective consumption of PMS, and δ13C ratios suggest that PMS is a major nutrient source for earthworms. Although concentrations of copper in the PMS are higher than those typical for soils, concentrations in earthworm tissue are relatively low. Low availability of copper will reflect the high content of organic matter and clay, and relatively high pH, of the PMS.

Some processes have been widely applied to biomass in order to take advantage of its energy potential. In particular, these processes are based on pyrolysis or gasification. In this study, briquetting was applied to olive refuse and paper mill waste to form fuel briquettes. For this purpose, the particle sizes of both biomass samples were decreased to −250 μm and then they were briquetted in a steel die under pressure between 150 and 250 MPa at ambient temperature. Effects of the moisture content of the biomass samples and briquetting pressure on the shatter index, compressive strength, and water resistance of the briquettes obtained were investigated. This study showed that the mechanical strength of the briquettes produced only from the olive refuse was not high enough. On the other hand, strong briquettes were produced using paper mill waste. When olive refuse was blended with fibrous paper mill waste, briquettes with sufficiently high mechanical strength could be produced. Burning profiles of the samples were derived applying derivative thermogravimetry technique under dynamic dry air atmosphere up to 1273 K with a heating rate of 40 K·min−1 and then combustion characteristics of the briquettes were compared.

The cultivation conditions for Rhizopus oryzae grown in synthetic medium and paper pulp spent sulfite liquor (SSL) were investigated to achieve high biomass and ethanol yields using shake flasks and bioreactors. The fungus assimilated the hexoses glucose, mannose and galactose, and the pentoses xylose and arabinose as well as acetic acid which are present in SSL. The assimilation of hexoses was faster than pentoses during cultivation in a synthetic medium. However, all sugars were assimilated concomitantly during growth in SSL supplemented with ammonium, magnesium, calcium, phosphate, sulfate and trace amounts of some other metal ions (SSL-S). The medium composition had an important influence on biomass yield. The highest biomass yields, viz. 0.18 and 0.43 g biomass/g sugar were obtained, when the cells were cultivated in shake flasks with a synthetic medium containing glucose as carbon and energy source and SSL-S, respectively. The corresponding yields in a bioreactor with more efficient aeration were 0.22 and 0.55 g/g. In addition to the biomass, ethanol, lactic acid, and glycerol were important extracellular metabolites of the cultivation with maximum yields of 0.37, 0.30 and 0.09 g/g, respectively. When the source of sugars in the medium was exhausted, the fungus consumed the metabolites produced, such that the liquid medium was depleted of potential oxidizable nutrients. In general, there was a direct competition between lactic acid and ethanol among the metabolites. Poor medium compositions and cultivation conditions resulted in higher yields of lactic acid, whereas the ethanol and biomass yields were higher in rich media. SSL-S supported good growth of mycelium and a high ethanol yield.

As an alternative renewable energy source, methane production in biogas plants is gaining more and more attention. Biomass in a bioreactor contains different types of microorganisms, which should be considered in terms of process-stability control. Metabolically inactive microorganisms within the fermentation process can lead to undesirable, time-consuming and cost-intensive interventions. Hence, monitoring of the cellular metabolism of bacterial populations in a fermentation broth is crucial to improve the biogas production, operation efficiency, and sustainability. In this work, the extracellular acidification of bacteria in a paper-fermentation broth is monitored after glucose uptake, utilizing a differential light-addressable potentiometric sensor (LAPS) system. The LAPS system is loaded with three different model microorganisms (Escherichia coli, Corynebacterium glutamicum, and Lactobacillus brevis) and the effect of the fermentation broth at different process stages on the metabolism of these bacteria is studied. In this way, different signal patterns related to the metabolic response of microorganisms can be identified. By means of calibration curves after glucose uptake, the overall extracellular acidification of bacterial populations within the fermentation process can be evaluated.

We studied vermicomposting with Eisenia andrei of sludges from a paper mill mixed with cattle manure in a six-month pilot-scale experiment. Initially, a small-scale laboratory experiment was carried out to determine the growth and reproduction rates of earthworms in the different substrates tested. In the pilot-scale experiment, the number of earthworms increased between 22- and 36-fold and total biomass increased between 2·2- and 3·9-fold. The vermicomposts were rich in nitrogen and phosphorus and had good structure, low levels of heavy metals, low conductivity, high humic acid contents and good stability and maturity. These sludges could be potentially useful raw substrates in larger commercial vermicomposting systems, and would reduce the costs related with the exclusive use of different types of farm wastes as feed for earthworms.

During the summertime, water hyacinth, Eichhornia crassipes (Mart.) Solms, was produced on paper-industry effluent, in a 1 hectare lagoon, as a finishing treatment. This paper describes the evolution of the culture (cover area, biomass production). The available space was covered up to 60% within four months with an average production of 66·6 g d.wt d−1 m−2. At the beginning, the culture was restrained by the effluent foam and, thus, an initial biomass of 100 kg fresh weight was necessary for its development. The lack of available space restrained the covering speed of the lagoon after 60% coverage. The harvest of the water hyacinths, 220 tons fresh weight, was carried out during the fifth month and was very difficult because of the entanglement of the plants. So, harvesting had to be carried out in order to reduce the plant cover from 50 to 25%, when harvesting was still easy but treatment was still efficient.

Catalytic co-pyrolysis of biomass and plastics (HDPE (high density polyethylene), PP (polypropylene) and PET (polyethylene terephthalate)) has been performed in a fixed-bed reactor in presence of cobalt based alumina, ceria and ceria-alumina catalysts to analyze the product distribution and selectivity. Catalysts are synthesized using co-precipitation method and characterized by BET (Brunauer-Emmett-Teller) surface area and XRD analysis. The effect of catalytic co-pyrolysis at different temperature with product distribution has been evaluated. The results have clearly shown the synergistic effect between biomass and plastics, the liquid products gradually increases forming with rise in the plastic content in the blend. Gaseous products have yielded most during pyrolysis of blend having biomass/plastics ratio of 5:1 with the presence of 40% Co/30% CeO2/30% Al2O3 catalyst with hydrogen gas production touched its peak of 47 vol%. Catalytic performance enhanced with increase with the cobalt loading, with best performance attributing to 40% Co/30% CeO2/30% Al2O3 catalyst. (C) 2016 Elsevier Ltd. All rights reserved.

Land application of organic wastes to short rotation woody crops (SRWC) can reduce the environmental impacts associated with waste disposal and enhance the productivity of biomass production systems. Understanding the potential impacts of organic amendments however, requires the examination of changes in soil characteristics and plant productivity. This study was conducted to evaluate the effect of paper sludge and dairy manure on biomass production of shrub willow (Salix dasyclados SV1) and to determine the impacts of these amendments on soil chemical properties. Treatments included urea, dairy manure and paper sludge separately and in combination, and a control. These materials were applied in the summer of 2005 to two fields of SV1 at different stages of growth: An old field with one year old shoots on a 10 year old root system and a young field which was beginning regrowth after being coppiced at the end of its first growing season. Foliar nutrient concentrations and soil chemical properties were analyzed at the end of the second growing season after treatment application to determine plant response to the fertilization regimes and to determine the effects of fertilization on soil characteristics. Fertilization did not increase biomass production in either field. However, application of the N-poor paper sludge did not reduce yield either. In general, fertilization did not influence soil or foliar chemistry, although there were some exceptions. The lack of response observed in this study is probably related to the nutrient status of the site or losses of applied nutrients.

Densified biomass pellets using waste wood sawdust (S) as main materials and wrapping paper fiber (P) as “solid bridge”, named as P/S-BPs, was prepared by a hydraulic press powder pelletizer under room temperature and pressure lower than10 MPa. The effects of the addition of P to S and the compressed pressure on the density, resiliency (R), abrasion resistance (AR), impact resistance index (IRI)) and the combustion behavior of the P/S-BPs were investigated. The results showed that the addition of P to S greatly reduced the negative effects of resiliencies on the densities and mechanical properties of P/S-BPs during storage. For example, P/S-BPs compressed at 6 MPa in a P/S mass ratio of 1–3 showed the smooth surface and low resiliency of 10% with a high relaxed density of 1.08 kg m −3 . This is due to the strengthened interlocking bonds through fabricating “solid bridge” and increasing attracting force by adding P to resist the disruptive force created by elastic recovery even under low pressure. Combustion results showed that the addition of P decreased the soot index (SI) due to the lower devolatilization rate and burnout rate, and increased the HHV per unit volume because of its high relaxed density. Thus, compression of waste P and S in a P/S mass ratio of 1–3 at room temperature under 6 MPa is a cost-effective process to produce densified sustainable bio-fuel from waste S and P as well as dispose them.

Rice straw, rice husk and paper sludge are by-products and industrial waste, and are beneficial resources as raw biomass materials used for manufacturing value-added composite products. We investigated the effect on selected mechanical properties of adding rice straw, rice husk and paper sludge to wood composites to replace wood particles for manufacturing green pallets. Results showed that increasing the contents of rice straw and rice husk dramatically decreased the mechanical strength of the composites. This is because the wax and silicate coating of these materials obstructed the strong bonding with UF resin. When 10 wt.% of wood particle was replaced with 10 wt.% of paper sludge, the wood–paper sludge composites showed similar mechanical properties to those of wood particle. Wood particle can be replaced by 10 wt.% of dried paper sludge in accordance with the minimum requirement recommended by standards in green pallet manufacturing.

The significance of technical data, as well as the significance of system boundary choices, when modelling the environmental impact from recycling and incineration of waste paper has been studied by a life cycle assessment focusing on global warming potentials. The consequence of choosing a specific set of data for the reprocessing technology, the virgin paper manufacturing technology and the incineration technology, as well as the importance of the recycling rate was studied. Furthermore, the system was expanded to include forestry and to include fossil fuel energy substitution from saved biomass, in order to study the importance of the system boundary choices. For recycling, the choice of virgin paper manufacturing data is most important, but the results show that also the impacts from the reprocessing technologies fluctuate greatly. For the overall results the choice of the technology data is of importance when comparing recycling including virgin paper substitution with incineration including energy substitution. Combining an environmentally high or low performing recycling technology with an environmentally high or low performing incineration technology can give quite different results. The modelling showed that recycling of paper, from a life cycle point of view, is environmentally equal or better than incineration with energy recovery only when the recycling technology is at a high environmental performance level. However, the modelling also showed that expanding the system to include substitution of fossil fuel energy by production of energy from the saved biomass associated with recycling will give a completely different result. In this case recycling is always more beneficial than incineration, thus increased recycling is desirable. Expanding the system to include forestry was shown to have a minor effect on the results. As assessments are often performed with a set choice of data and a set recycling rate, it is questionable how useful the results from this kind of LCA are for a policy maker. The high significance of the system boundary choices stresses the importance of scientific discussion on how to best address system analysis of recycling, for paper and other recyclable materials.

Summary Commercially processed vermicomposts, produced from food wastes, paper wastes and cattle manure, were applied to 8.25 m 2 field plots, at rates of 10 or 20 t/ha in 1999 and 5 or 10 t/ha in 2000, to evaluate their effects on the growth and yields of peppers ( Capsicum annuum ) var. King Arthur. The vermicomposts were incorporated into the upper 10 cm of soil and supplemented, based on chemical analyses, with amounts of inorganic NPK fertilizers calculated to equalize initially with the rates of 95-95 NK kg/ha applied to the inorganic fertilizer control plots. Phosphorus was determined to be adequate in soils at the experiment site so was not added. All treatments were replicated four times in a randomized complete block design. The vermicompost applications increased the growth and yields of peppers significantly; including increased leaf areas, plant shoot biomass, marketable fruit weights and decreased yields of non-marketable fruit. Application of vermicomposts to soils increased their microbial biomass and dehydrogenase activity. Humic materials and other plant growth-influencing substances, such as plant growth hormones, produced by microorganisms during vermicomposting, and produced after increased microbial biomass and activity in soils, may have been responsible for the increased pepper growth and yields, independent of nutrient availability.

Paper machines can be made environmentally harmless by enclosing their water systems. However, consumption of dissolved solids then takes place in the whitewater. A purification system can be used to prevent this consumption. The integration of biological treatment into the water system of a paper machine is analysed in this paper. The concentration dynamics of the dissolved organic compound (DOC) and the reactor volume required in aerobic treatment are estimated. The required volume depends on the treatment; in advanced treatment it is 1 10 of the volume required in conventional treatment. The reactor can be made more productive by using higher biomass concentrations. The high biomass concentration can be consumed and maintained in a reactor by cross-flow filtration, used for separation of the sludge from treated water. A new model is proposed for the description of the concentration dynamics in the paper machine and membrane bioreactor. The model is applied for the prediction of DOC changes in whitewater, bulkwater, and treated water. Closed-cycle papermaking processes are analysed, based on a conventional reactor and a membrane reactor.

Briquetting may be considered as a good idea to utilise low grade combustible materials obtained from biomass sources. Studies demonstrated that waste paper and wheat straw or their mixtures can be compressed to a relative density greater than unity and stabilised at that density without binder material. A reduction in the volume of the material also provides its technological benefit, i.e., the material could be transported and stored more economically than is possible at present. The effects of the briquetting pressure on the density, moisture content and compressive strength of the briquettes were examined at six different pressures (300, 400, 500, 600, 700 and 800 MPa). The optimum moisture contents and briquetting pressures were found to be, respectively, 18% and 780 MPa for waste paper, 22% and 710 MPa for wheat straw and 18% and 750 MPa for a 20%(w) waste paper–straw mixture. The effect of the temperature on the briquette density of wheat straw was determined. The best wheat straw briquettes were obtained at 385 K.

An experimental apparatus, with the features of fast heating rate and continuous record of reaction parameters, was developed to study kinetics of fast pyrolysis. The temperature effects, at a range of 400°C to 900°C, on pyrolysis rate, products profile, gas quality and quantity, and so on, were studied and the results are listed and analyzed. The effect of secondary reaction of gas phase at 700°C was tested and the regression result is expressed in an experimental formula. Based on the experimental results, the three-stage-reaction mechanism module is suggested. The kinetic expression to calculate gas formation rate is concluded as: dαdt=Aexp(-ERT)(1-α)n . The kinetic parameters of A, E, and n at different temperatures are given in the paper.

European agriculture must progress towards a more multi-faceted utilization of different types of land in order to conserve arable land and thereby food production. The simultaneous production of food, energy and fibres appears economically viable . This also provides a solution to environmental problems of the community. The utilization of waste products as fertilizer when cultivating biomass should be done in such a way that we remain able to return rapidly to full-scale food production if unexpected developments occur. Thus crops chose must be able to be replaced rapidly by grain or pasture on land which has not experienced a loss of fertility or pollution by heavy metals.