Research on a Composite Biomass Insulation Material with Geopolymers as Binders and Forestry Waste as Fillers

A composite biomass insulation material,which uses geopolymers as adhesives and forestry waste as fillers,was proposed and experimentally tested.The orthogonal experimental method was adopted to analyze the optimum theoretical oxide molar ratios and the mass ratio of mixing water to binder(m_(w2)/m__(B))for preparing geopolymers.The influences of curing regimes(including one-stage and two-stage curing methods)and m_(w2)/m_(B) ratios of the insulation materials on mechanical,thermal,and hydraulic performances were also studied by experiment.The results indicated that the optimum combination scheme of preparing geopolymers was molar ratio x_(SiO_(2))/x_(Na_(2)O)=3.3,x_(SiO_(2))/x_(Al_(2)O_(3))=3.2 and m_(w2)/m_(B)=0.5 with the highest mechanical strength of 34.21 MPa.Besides,the best curing conditions of the composite material were the curing temperatures of 85°C and 70°C under the two-stage curing regime,which could achieve the low heat conductivity of 0.123 and 0.125 W/(m·K),and the high mechanical strength of 1.70 MPa and 1.71 MPa,respectively.The optimum m_(w2)/m_(B)ratios of the biomass material were 0.5 to 0.55 with heat conductivity of 0.114 to 0.125 W/(m·K).This novel composite insulation material has satisfying physical performances,which is helpful for achieving building energy conservation.

Durable flame-retardant,smoke-suppressant,and thermal-insulating biomass polyurethane foam enabled by a green bio-based system

Bio-based polyurethane foam has attracted increasing attentions due to eco-friendliness and fossil feedstock issues.However,the inherent flammability limits its application in different fields.Herein,we demonstrate a green bio-based flame-retardant system to fabricate polyurethane foam composite with durable flame retardancy,smoke suppression,and thermal insulation property.In this system,the green bio-based polyol(VED)with good reactivity and compatibility plays a role of flame retardant and EG acts as a synergistic filler.As a result,the LOI value of foam composite increased to 30.5 vol.%and it achieved a V-0 rating in the UL-94 vertical burning test.Additionally,the peak heat release rate(pHRR)and the total smoke production(TSP)decreased by 66.1%and 63.4%,respectively.Furthermore,the foam composite maintained durable flame retardancy after accelerated thermal aging test,whose thermal-insulating property was maintained even after being treated in high-humidity environment with 85%R.H.for a week.This work provides a facile strategy for durable flame retardancy and long-term thermal insulation performance,and creates opportunities for the practical applications of bio-based foam composites.

Characteristics of biomass ashes from different materials and their ameliorative effects on acid soils

The chemical characteristics,element contents,mineral compositions,and the ameliorative effects on acid soils of five biomass ashes from different materials were analyzed. The chemical properties of the ashes varied depending on the source biomass material. An increase in the concrete shuttering contents in the biomass materials led to higher alkalinity,and higher Ca and Mg levels in biomass ashes,which made them particularly good at ameliorating effects on soil acidity. However,heavy metal contents,such as Cr,Cu,and Zn in the ashes,were relatively high. The incorporation of all ashes increased soil p H,exchangeable base cations,and available phosphorus,but decreased soil exchangeable acidity. The application of the ashes from biomass materials with a high concrete shuttering content increased the soil available heavy metal contents. Therefore,the biomass ashes from wood and crop residues with low concrete contents were the better acid soil amendments.

Demo-scale production of protein-rich fungal biomass from potato protein liquor for use as innovative food and feed products

Innovative food and feed products have recently attracted the attention of both producers and consumers.Filamentous fungi are important biomass producers with their high protein contents.In this study,fungal biomass production from edible potato protein liquor (PPL),generated during starch production processes,was investigated through different fungal strains (Rhizopus oryzae ,R.oligosporus ,R.delemar ,Aspergillus oryzae and Neurospora intermedia ).The effects of PPL concentration,incubation time,initial pH,and cultivation conditions (in shake flaks and different scale reactors) were examined to determine the amount of biomass and its crude protein level.It was determined that the fungal biomass produced by R.delemar in industrial scale contained 53% crude protein.For this strain,the amino acid and fatty acid profiles as well as metals (iron,manganese,copper,and zinc) of the produced biomass were also investigated to assess possible use as a food or feed source.The R.delemar fungal biomass can be a promising raw material for feed and food production,for example,considering its protein and fatty acid profiles with 41% essential amino acids and 33% polyunsaturated fatty acids.

Composition of carbohydrates, surfactants, major elements and anions in PM2.5 during the 2013 Southeast Asia high pollution episode in Malaysia

Haze episodes have become a major concern in Malaysia over the past few decades and have an increasingly important impact on the country each and every year. During haze episodes from biomass burning in Southeast Asia, particularly from Sumatra, Indonesia, particulate matter PM2.5 is found to be one of the dangerous sources of airborne pollution and is known to seriously affect human health. This study determines the composition of carbohydrates （as levoglucosan）, surfactants, major elements, and anions in PM2.5 during a 2013 haze episode. PM2.5 samples were collected from Universiti Kebangsaan Malaysia, Bangi, using a high volume sampler during a seven-day monitoring campaign during the peak of that year＇s haze episode. PM2.5 concentrations ranged between 14.52 and 160.93 μg/m3, exceeding the 2005 WHO air quality guidelines for PM2.5 （25 μg/m3 for 24-h mean）. The patterns for levoglucosan, surfactants, major elements, and anionic compositions were proportional to the PM2.5 concentrations. Changes in PM2.5 observed on days 3 and 4 were influenced by a combination of meteorological factors, which substantiate the theory that such factors play a pivotal role in haze episodes.

Emissions from the combustion of eucalypt and pine chips in a fluidized bed reactor

Interest in renewable energy sources has increased in recent years due to environmental concerns about global warming and air pollution,reduced costs and improved efficiency of technologies.Under the European Union（EU）energy directive,biomass is a suitable renewable source.The aim of this study was to experimentally quantify and characterize the emission of particulate matter（PM（2.5））resulting from the combustion of two biomass fuels（chipped residual biomass from pine and eucalypt）,in a pilot-scale bubbling fluidized bed（BFB）combustor under distinct operating conditions.The variables evaluated were the stoichiometry and,in the case of eucalypt,the leaching of the fuel.The CO and PM（2.5）emission factors were lower when the stoichiometry used in the experiments was higher（0.33±0.1 g CO/kg and 16.8±1.0 mg PM（2.5）/kg,dry gases）.The treatment of the fuel by leaching before its combustion has shown to promote higher PM（2.5）emissions（55.2±2.5 mg/kg,as burned）.Organic and elemental carbon represented 3.1 to 30 wt.% of the particle mass,while carbonate（CO3^（2-））accounted for between 2.3 and 8.5 wt.%.The particulate mass was mainly composed of inorganic matter（71% to 86% of the PM（2.5）mass）.Compared to residential stoves,BFB combustion generated very high mass fractions of inorganic elements.Chloride was the water soluble ion in higher concentration in the PM（2.5）emitted by the combustion of eucalypt,while calcium was the dominant water soluble ion in the case of pine.

Effects of road dust on the growth characteristics of Sophora japonica L.seedlings

Road dust is one of the most common pollutants and causes a series of negative effects on plant physiology. Dust＇s impacts on plants can be regarded as a combination of load,composition and grain size impacts on plants; however, there is a lack of integrated dust effect studies involving these three aspects. In our study, Sophora japonica seedlings were artificially dusted with road dust collected from the road surface of Beijing so that we could study the impacts of this dust on nitrogen/carbon allocation, biomass allocation and photosynthetic pigments from the three aspects of composition, load and grain size. The results showed that the growth characteristics of S. japonica seedlings were mostly influenced by dust composition and load. Leaf N, root–shoot ratio and chlorophyll a/b were significantly affected by dust composition and load; leaf C/N, shoot biomass, total chlorophyll and carotenoid were significantly affected by dust load; stem N and stem C/N were significantly affected by dust composition; while the dust grain size alone did not affect any of the growth characteristics. Road dust did influence the growth characteristics more extensively than loam. Therefore, a higher dust load could increase the differences between road dust and loam treatments. The elements in dust are well correlated to the shoot N, shoot C/N, and root–shoot ratio of S. japonica seedlings. This knowledge could benefit the management of urban green spaces.

Chemical composition and properties of ashes from combustion plants using Miscanthus as fuel

Miscanthus giganteus is one of the energy crops considered to show potential for a substantial contribution to sustainable energy production. In the literature there is little data available about the chemical composition of ashes from the combustion of Miscanthus and practically no data about their physical properties. However, for handling, treatment and utilization of the ashes this information is important. In this study ashes from two biomass combustion plants using Miscanthus as fuel were investigated. The density of the ashes was 2230 ± 35 kg/m;, which was similar to the density of ashes from straw combustion. Also the bulk densities were close to those reported for straw ashes. The flowability of the ashes was a little worse than the flowability of ashes from wood combustion. The measured heavy metal concentrations were below the usual limits for utilization of the ashes as soil conditioner. The concentrations in the bottom ash were similar to those reported for ash from forest residue combustion plants. In comparison with cyclone fly ashes from forest residue combustion the measured heavy metal concentrations in the cyclone fly ash were considerably lower. Cl-, S and Zn were enriched in the cyclone fly ash which is also known for ashes from wood combustion. In comparison with literature data obtained from Miscanthus plant material the concentrations of K, Cl-and S were lower.This can be attributed to the fact that the finest fly ash is not collected by the cyclone de-dusting system of the Miscanthus combustion plants.