Development of a Composite Material Based on Wood Waste Stabilized with Recycled Expanded Polystyrene

Environmental pollution is a whole world concern. One of the causes of that pollution is the proliferation of plastic waste. Among these wastes there is expanded polystyrene (EPS), mainly from packaging. This study aims to valorize EPS waste by developing a composite material from EPS waste and wood waste. For this purpose, a resin made of EPS has been elaborated by dissolving EPS in acetone. That resin was used as a binder in volume proportions of 15%, 20%, 25% and 30% to stabilize the samples. Some of them were thermoformed. The method of elaboration was based on a device consisting of an extruder for mixing the constituents, and a manual press for shaping and compacting the samples. Analyses show that the drying time depends on the composition of the mixture. Increasing the resin content leads to reduce water absorption and porosity of the samples;it also contributes to homogenize the internal structure of the samples. However, for the same resin contents, the thermoformed samples are less porous;they have more homogeneous internal structure;and absorb less water than non-thermoformed samples.

Wood waste biochar promoted anaerobic digestion of food waste:focusing on the characteristics of biochar and microbial community analysis

Anaerobic digestion(AD)has been considered as a promising technique for food waste(FW)recycling.However,the accumulation of volatile fatty acids(VFAs)restricts the stability of anaerobic reactors.The present study investigated the use of biochar produced at different conditions(750℃-30 min,750℃-60 min,750℃-120 min,550℃-60 min,650℃-60 min,850℃-60 min,950℃-60 min)for enhancing the AD of FW.Batch experiments showed that all the biochar increased the methane production rates and biochar obtained at 750℃-60 min resulted in the highest enhance-ment by 21.5%.It was further showed surface oxygen-containing functional groups and graphitization degree of biochar were the critical factors for improving methane production.Microbial analysis showed that biochar addi-tion formed different microbial communities,and Methanosaeta,Romboutsia,and norank_f_Anaerolineaceae were enriched,which might be correlated with direct interspecies electron transfer(DIET).This research showed biochar could enhance the AD of FW and also revealed the main characteristics of biochar relating with the enhancement of AD.

Growth Response of Bacterial Antagonists in a Mix of Composted Wood Fibre Waste and Millet Seed under Sterile and Non-sterile Conditions

The potential use ofcomposted wood fibre waste （WFW） for the cultivation of bacterial antagonists of Sclerotinia minor was examined with the result that a mix of millet seed （20% w/w） and WFW, suitably amended with nutrients, proved to be an ideal matrix for the growth of some of these bacteria. Densities in terms ofcfu＇s ranged from 8.5 IOgl0 cfu/g dw to 10.5 logl0 cfu/g dw ullder sterile conditions after 14 days incubation. Lower population densities of the antagonists were achieved under non-sterile conditions in the compost： millet mix of between 7.9-9.3 logm cfu/g dw at the same period. However, when applied in a pot （glasshouse） trial to protect against S. minor, the millet seed appeared to stimulate the growth of this pathogen resulting in a high incidence of attack of lettuce plants after 2-3 weeks. Although the percentage of healthy seedlings increased following application of compost mix grown antagonists （at a rate of 5% v/v） when compared to the control treatment, these values were not statistically significant （p〉0.05） in most cases. Therefore, the use of millet seeds cannot be recommended as a nutrient supplement for the bacterial antagonist cultivation, if to be subsequently used to control fungal pathogens in the field.

An Assessment of the Potential Use of Forest Residues for the Production of Bio-Oils in the Urban-Rural Interface of Louisiana

Louisiana is endowed with forest resources. Forest wastes generated after thinning, land clearing, and logging operations, such as wood debris, tree trimmings, barks, sawdust, wood chips, and black liquor, among others, can serve as potential fuels for energy production in Louisiana. This paper aims to evaluate the potential annual volumes of forest wastes established on detailed and existing data on the forest structure in the rural-urban interface of Louisiana. It also demonstrates the state’s prospects of utilizing forest wastes to produce bio-oils. The data specific to the study was deduced from secondary data sources to obtain the annual average total residue production in Louisiana and estimate the number of logging residues available for procurement for bioenergy production. The total biomass production per year was modeled versus years by polynomial regression curve fitting using Microsoft Excel. Results of the model show that the cumulative annual total biomass production for 2025 and 2030 in Louisiana is projected to be 80000000 Bone Dry Ton (BDT) and 16000000 (BDT) respectively. The findings of the study depict that Louisiana has a massive biomass supply from forest wastes for bioenergy production. Thus, the potential for Louisiana to become an influential player in the production of bio-based products from forest residues is evident. The author recommends that future research can use Geographic Information Systems (GIS) to create maps displaying the potential locations and utilization centers of forest wastes for bioenergy production in the state.

Alternative feedstock for the production of activated carbon with ZnCl_(2):Forestry residue biomass and waste wood

In order to substitute fossil resources in activated carbon(AC)production,recent efforts have focused on the utilization of renewable raw materials.Regions with important wood industries offer two potentially underestimated resource types:forestry residue biomass(FRB)and waste wood(WW).Although these materials are widely available(approx.130 mio.m3a-1 FRB,approx.50 mio.ta^(-1) WW in the EU),they are mostly valorised through energy production,as they are high in ashes and may be contaminated with organics and heavy metals.In this study,both FRB and WW were treated via one-step pyrolysis for AC production.ZnCl_(2) was applied as activating agent at pyrolysis temperatures varying from 400 to 600℃ and residence times between 1 and 3 h.Overall,76 samples were prepared and characterized thoroughly via elemental analysis,N_(2)/CO_(2) ad/-desorption,thermogravimetric analysis(TGA),scanning electron microscopy(SEM),and infrared spectroscopy(FTIR).The produced carbons showed specific surface areas of up to 1430 m2g􀀀1 and a pore size distribution with a micropore share of up to 80%.The presence of oxygen-containing functional groups was confirmed via FTIR.Potential feedstock contamination can be mitigated,as minerals and heavy metals could be leached out(up to-99.15%)by an additional wash step and organic contamination undergoes thermal cracking during pyrolysis.The presented study could be a next step in upcycling considerable waste streams from the wood sector through localised and non-fossil-based AC production.

Carbon-negative cement-bonded biochar particleboards

Biochar from bio-waste pyrolysis presents excellent CO_(2) sequestration capacity.This study innovated the design of cement-bonded particleboards utilizing a substantial amount of 50-70 wt.%pre-soaked biochar to render the products carbon-negative.We investigated the roles of biochar in magnesium oxysulfate cement(MOSC)system and demonstrated good mechanical and functional properties of biochar cement particleboards.In the presence of biochar,the amounts of hydration products were enriched in the cement systems as illustrated by the thermogravi-metric analyses(TGA)and X-ray diffraction(XRD).We further incorporated supplementary cementitious materials(SCMs)and generated 5 Mg(OH)_(2)⋅MgSO_(4)·7H_(2)O(5-1-7)phase in the MOSC system.As a result,our designs of biochar particleboards satisfied the standard requirements for flexural strength(>5.5 MPa)and thickness swelling(<2%).Moreover,our biochar particleboards presented a low thermal conductivity as the biochar pores disrupted thermal bridging within particleboards.We illustrated that the high dosage ratio of biochar could significantly offset the CO_(2) emissions of the particleboards(i.e.,carbon-negative)via life cycle assessment.Noticeable economic profits could also be accomplished for the biochar particleboards.For instance,the 50BC-MOSC bonded particleboard(with 50 wt.%pre-soaked biochar as aggregate,50 wt.%MOSC as binder)with promising mechanical properties could store 137 kg CO_(2) tonne^(−1) and yield an overall economic profit of 92 to 116 USD m^(−3) depending on the carbon prices in different countries.In summary,our new designs of carbon-negative biochar particleboards could curtail carbon emissions in the construction materials and promote the realization of carbon neutrality and circular economy.