Dry Pine Needles Research Articles

Inherent water in green pine needles and cypress leaves induces self-activation in microwave pyrolysis

The response of water to microwaves creates the possibility of activating green waste for the generation of porous biochar with inherent water. This hypothesis is verified herein through the microwave pyrolysis of green and dried pine needles and cypress leaves at 500 to 800 °C. The results indicate that the inherent water in the green samples induce steam reforming or gasification, thereby forming more gases at the expense of biochar and organics, such as light and heavy phenolics in bio-oil. The intensive gasification induced by the inherent water of green pine needles effectively promotes the pore development of biochar at 800 °C (805.9 versus 360.4 m2/g from the dried sample) and the adsorption of phenol (50.3 versus 34.8 mg/g from the dried sample). A similar result is observed for the pyrolysis of cypress leaves at 800 °C (452.1 m2/g from the green samples versus 110.8 m2/g from the dried samples). A lower temperature (i.e., 500 °C) with insufficient gasification results in no marked difference in pore development. Accelerated gasification with steam leads to the excessive removal of aliphatic organics but also introduces more oxygen in the biochar, making it more hydrophilic with a more fragmented surface. Nevertheless, potential local hot spots, if any, do not lead to the decomposition of inorganics, such as CaCO3, in the pyrolysis of green samples, while the pyrolysis of dried cypress does. The pyrolysis in in-situ infrared shows that 500 °C is required to effectively destruct hydrogen bonds in the green samples and the inherent water promotes the formation of more oxygen-containing functionalities but not aromatization.

Effects of Fuel Bed Slope and Wind Direction on Flame Spread Characteristics Over a Bed of Pinus Silvestris Needles

ABSTRACT Important factors influencing the flame characteristics over a bed of dry pine needles from Siberian Boreal forests (Pinus silvestris) in lab-scale is provided. Factors such as slope of the fuel bed, wind velocity, and direction of spread (concurrent flow or opposed flow), which play significant roles in determining the flame spread rate, have been investigated. Systematic lab-scale experiments have been carried out in a wind tunnel with varying air velocities and on an inclined fuel bed in still air. Numerical simulations have been carried out using a three-dimensional physics-based flame spread model available in Fire Dynamics Simulator, and the results are validated against a wide range of measured flame characteristics. The validated numerical model is then used to simulate concurrent flow and opposed flow flame spread over a sloping fuel bed in the presence of wind. Gas phase temperature on and above the bed surface and total and radiative heat flux measurements for concurrent flow and opposed flow flame spread under the influence of wind as well as for upslope flame spread in still air are presented. A stationary flame propagation mode is observed for a flat fuel surface. Predicted temperature, flow, and species concentration fields have been reported for selected cases to understand the flow and flame dynamics in gas phase and within the fuel beds. These data serve as a validation of the numerical model used for simulating the experimental cases. Further, it can be used to validate popular fire models such as Fire Foam and Fire-Star 3D.

Varied directions of heat flow and emission of volatiles impact evolution of products in pyrolysis of wet and dry pine needles

In pyrolysis of biomass via furnace heating, directions for travel of volatiles and heat flow are opposite. This is drastically different from simultaneously heating surface/inner core of a biomass particle with microwave heating. Changing direction of heat flow and volatiles affects volatiles-char interactions and evolution of pyrolytic products. This was investigated herein by pyrolysis of wet and dry pine needles via furnace or microwave heating at 600 °C. The results indicated that microwave heating induced intensive cracking of outer/inner structures of pine needles. This promoted gasification, decreased production of biochar/bio-oil, diminished formation of both light and heavy organics in bio-oil. Microwave heating also accelerated aromatization, forming biochar of higher C/O and C/H ratios and thermal stability. Additionally, formation of “hot spot” in pyrolysis of wet pine needles via microwave heating was evidenced by the phenomenon of decomposition of CaCO3 to CaO in pyrolysis, which also contributed to enhanced aromatic degree of biochar. Besides, pyrolysis of wet pine needles via microwave heating also generated developed pore structures in biochar (151.4 m2 g−1), as the inherent water and carbonaceous organics were heated simultaneously. Hydrogen bonding from inherent water was largely cracked only above 500 °C. Prolonged retention time of H2O reacted with carbonaceous intermediates, generating more aliphatic structures. Additionally, microwave heating also induced formation of unique morphology like massive thorn-like particulate matters on biochar.

Ignition of Wildland Fuels Exposed to a Time-Decreasing Incident Heat Flux

ABSTRACT The effect of decreasing incident heat fluxes on the ignition delay time of dry pine needles is addressed in the present study. A customized modular instrument (I-FIT) that uses radiant heaters to simulate idealized firebrands ensures experimental repeatability for combustion experiments. Linear incident heat flux ramps are obtained by controlling the power of the heating element, thus simulating idealized firebrands. An analytical model based on the thermal ignition theory was developed and solved analytically using an integral approach. This model includes convective losses and in-depth penetration of radiation. Radiation was modeled using the P1 approximation. The theoretical model is complemented and validated by experimental data, showing increments of the ignition delay times when the negative slope steepness over time increases for the same heat flux. For given values of the initial incident heat flux on the sample, a critical slope is observed. For slopes steeper than this critical value, ignition is not attained.

Valorization potential of pine needle waste biomass: recent trends and future perspectives.

Pines play a significant role in forest biodiversity globally and generate huge forest litter. Dry pine needles due to low ignition temperature and high frictional force with the ground catch fire quickly. Annual forest fires in the northern states of India greatly impact the Indian economy besides causing huge loss to biodiversity, livelihood, and environment. Pine needles are also considered unfit for fodder consumption due to presence of tannins. Although the presence of softwood lignin in pine needles makes it difficult to degrade easily, the presence of holocellulose (68.5%) containing 45-51% cellulose makes this biomass a potential substrate to be used in pulp-making industries for low-grade paper sheets. The good fiber length of pine needles (1.3-1.4mm) with a diameter of 30-32μm, maybe considered important property for paper making. The use of pine needles in the pharmaceutical and food industries are due to the presence of secondary metabolites (α-pinene, β-pinene, caryophyllene etc.). The various other potential applications of pine needles are for producing bio-ethanol (yield, 3.98%; purity, 94%), biogas (yield, 23.1 L kg-1), smokeless briquettes (calorific value, 18.77MJkg-1), biochar (calorific value, 25.6MJkg-1), bio-composites (tensile strength, 21-60MPa), and bio-pesticides. This paper comprehensively reviews the current applications of pine needles along with its future prospective applications that can have the dual advantage of providing employment opportunities to the people along with environmental protection.

Weed suppression by mulches in Mentha x piperita L.

The suitability of mulch for weed control in cultivated Mentha x piperita L. has been insufficiently studied. The results of this study show that this crop is sensitive to weed infestation. The objective was to evaluate the effects of mulch materials on weed suppression and yield of M. piperita. Two organic mulches, sawdust of acacia and dry pine needles, and two synthetic mulches, silver-brown and black “agrotextile” film, were compared with hand-weeded and non-weeded controls. Weed density and biomass per species were reduced in all treatments. The best biomass reduction was achieved with silver-brown film (96.3–100%) followed by black “agrotextile” film (74.6–95.9%). The treatments also reduced total dry weed biomass; the synthetic ones reduced biomass in the range of 84.6–100%, and the organic ones 28.5–81.4%. Under synthetic mulches, M. piperita generally achieved higher yields than under organic mulches. The best yields were obtained in 2016 with black “agrotextile” film (4.2 t ha−1) and in 2017 with silver-brown film (1.5 t ha−1). Significant differences in the relative chlorophyll content of M. piperita leaves were observed between treatments. The lowest inhibition of relative chlorophyll content compared to the hand-weeded control was observed in synthetic mulches. They ranged from − 1.93–4.53%, confirming their superiority in terms of the herbal drug M. piperita. The outcomes of this study show that the application of synthetic mulches, especially the silver-brown film, seems to be the most suitable model for non-chemical weed control in M. piperita cultivation.

A study in the synthesis of new Pinus wallichiana derived spherical nanocellulose hydrogel and its evaluation as malachite green adsorbent

Owing to the rich surface chemistry, high mechanical properties, bioadsorbability, low toxicity along with high abundance, nanocellulose (NC) has become a sustainable bionanomaterial feedstock to derive smart materials. In the present study, spherical nanocellulose (SNC) was synthesized from cellulose extracted from fallen and dried pine needles (PNs) by mixed acidic hydrolysis. It was followed by surface modification by grafting of 2-acrylamido-2-methylpropane sulphonic acid (AMPSA) using potassium persulphate (KPS)–N,N′-methylenebisacrylamide (MBAm) as the initiator-crosslinker system to form SNC-g-poly(AMPSA)-cl-MBAm hydrogel. SNC and SNC-g-poly(AMPSA)-cl-MBAm hydrogel were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), Field emission scanning electron microscopy (FESEM), and energy dispersive X-ray spectroscopy (EDS). The hydrogel was evaluated as an adsorbent for the removal of some cationic and anionic dyes. Preliminary adsorption studies on candidate dyes showed maximum adsorption for malachite green (MG) (N-methylated diaminotriarylmethane), a cationic dye. Hence, its adsorption was further investigated as a function of time, temperature, pH, and concentration from its aqueous solutions. Linear regression analysis was used to determine the isotherm parameters. The adsorption kinetics and adsorption isotherm studies showed that the adsorption process followed pseudo-second-order kinetics and Langmuir adsorption isotherm. The Langmuir maximum adsorption capacity (qm) was 357.143 mg/g at 60 min, 6.0 pH, and 30 °C. The results indicated that hydrogel is a rapid and efficient adsorbent for the removal of cationic dyes from wastewater.

A fuzzy Analytic Hierarchy Process based analysis for prioritization of enablers to pine briquettes based energy generation in alignment with the United Nations’ sustainable development goals: Evidence from India

Pine needles are a major cause of forest fires in the western region of the Himalayas in India. There is a need to explore avenues for utilizing this forest bio residue. Pine needles in the form of briquettes are an important source of renewable energy as it has low carbon emissions, low-cost technological interventions, easy accessibility and direct community benefits. The purpose of this paper is to list, classify and rank the enablers supporting energy generation using briquettes made from dried pine needles. This study ranks the enablers by using the fuzzy Analytic Hierarchy Process which is a multi-criteria decision-making approach. This paper finds that technological enablers are key to such interventions using dried and fallen pine needles for energy generation. The second category is environment-related enablers that directly impact the environment, followed by the market-related factors including good demand for the bio briquettes by the industry, viable fuel linkage, and a sense of business approach among the main actors. Economic enablers are next in importance, including factors such as employment generation, additional income, and self-sufficiency making such initiatives attractive enough to be adopted by people. Government and lastly, social and community-related enablers are next in priority for such projects. This is the first research that recognized, classified as well as ranked these enablers to pine needle-based energy generation in Uttarakhand in achieving United Nations’ Sustainable Development Goals for 2030 such as climate action and affordable and clean energy.

Prospecting Pine Needles to Develop Smart Materials for Specialty Applications

The use of the modified lignocellulosic materials in frontline technologies is an area of current and future interest. It is both a challenge and opportunity for researchers and technologists to transform the huge renewable green wealth into alternate materials through value addition. The present paper reports synthesis of new whole biomass-based hydrogels derived from a huge renewable forest waste - fallen and dry pine needles of the Himalayas. The synthesized materials have been evaluated as soil binders. This is the first-ever such report in the literature

Differential analysis of green and dry pine needles for their morphological and physiochemical attributes

Differential analysis of green and dry pine needles for their morphological and physiochemical attributes

Equilibrium and kinetic studies on adsorption of chromium(VI) onto pine-needle-generated activated carbon

Chromium is extensively used in a large number of industries and is often discharged through the wastewater effluents to pollute water sources. Being a heavy metal, it invariably leads to serious health risks when ingested. The aim of the present study is to test a readily available low-cost precursor, dry pine needles, for the production of activated carbon and determine its efficiency in removing Cr(VI) from water. Process parameters such as efficiency of metal removal, capacity of the activated carbon, pH, and concentration of adsorbate were investigated. The characterization of the adsorbent was performed using scanning electron microscopy and X-ray diffraction. The point of zero charge was determined. Both batch and column adsorption experiments were conducted. Adsorption equilibrium isotherms as well as adsorption kinetics were generated from batch experiments. Breakthrough curves were generated to assess adsorption capacities using column adsorption tests. The results obtained from the batch tests showed that the Freundlich as well as Temkin isotherms constituted a better fit for the adsorption data than the Langmuir isotherm. Maximum adsorption capacity of pine-needle activated carbon for Cr(VI) was 65.36 mg g−1. Furthermore, the adsorption kinetics followed a pseudo-second order which confirms chemisorption to be the mechanism responsible for the removal of Cr(VI) using pine-needle activated carbon as adsorbent. The results of the column tests indicated that the highest metal removals were achieved at lower initial concentrations, while the highest adsorption capacities were achieved at the initial concentration of 20 mg L−1. The results also depicted that Cr(VI) is almost exclusively removed at low pH values (pH 4 being the lowest pH tested) with removals decreasing appreciably with the increase in pH.

Impact of Ultrasound-Assisted Extraction on Supercritical Recovery of Valuable Compounds from Dry Pine Needles

Impact of Ultrasound-Assisted Extraction on Supercritical Recovery of Valuable Compounds from Dry Pine Needles

Pine needle biomass gasification based electricity and cold storage systems for rural Himalayan region: optimal size and site

Pine trees cover large portions of the Himalayan region. Every summer session dry pine needles fall from the trees and cover the forest floor, which is a serious cause of uncontrolled frequent forest fires here in this region. Due to the widespread availability of pine needles (forest biomass) in the Himalayan region, it can not only produce electricity (through gasification) for immediate local consumption and the national grid system but with the implementation of CHP and CHCP technology it can also contribute to local dairies, food processing industries and for cold storage. Using pine needles in electricity generation will not only save the environment, by preventing forest fires, but also contribute to the energy demands of the region and preserve the local vegetable, fruits and milk product without any additional cost. The objective of this study is to find out the optimal gasification system range to serve a particular locality with respect to local pine needle availability and produced refrigeration capacity.

Preliminary investigation on efficiency of muches and other mechanical weeding methods applied in Mentha piperita L.: Cultivation

Peppermint (Mentha x piperita) is a perennial, medicinal and aromatic, cultivated plant species belonging to Lamiaceae family. In this study, survey of 9 organic mulches (straw, chopped pieces of the pine bark, sawdust of acacia, cardboard, dry pine needles, chopped maize sedge, chopped pieces of the acacia bark, herbal composts 1 and 2), 1 biodegradable (black mulch film) and 4 plastic mulch films (silver-brown, perforated black, black, black “agrotextil”) were tested in Mentha x piperita experimental cultivation, located in Serbia. Three different models were used for application of mulches and films in the early spring of 2015. The plots were separated on two parts, one with hand weeding and the other one without weeding. Identical rows with peppermint were used as a double control, with no use of mulches/films; one control was kept free of weeds (C1 - weeds were manually removed), while the second one was kept intact (C2 - no weeds removal). Comparing to control treatment silver-brown polyethylene film (sPE), black agrotextil film (BA) and two organic mulches (sawdust of acacia and pine needles), showed very good effects on peppermint yield and reduction of weed biomass. Therefore, we selected them for further investigation. The aim of this study was to evaluate and select the best application models of organic mulches and mulch films for further investigation which will lead to the achievement of the highest yield of good quality peppermint herbal drug.

Ignition conditions and characteristics for high-porosity condensed materials subjected to local conductive heating

An experimental study of the ignition conditions (limiting heat source temperature) and characteristics (delay time) for high-porosity condensed materials under local conductive heating is reported. The study has been carried out on dry pine needles, a typical high-porosity combustible forest material. The dependence of the ignition delay for the material on the initial temperature of the heat source—a single cylindrical particle preheated to a high temperature—has been elucidated. A hypothesis concerning the mechanism of ignition of high-porosity condensed materials under local conductive heating has been formulated: the effect of high open porosity on the intensity of heat and mass transfer in the boundary layer of the material in the induction period has been substantiated.

Mulch type and moisture level affect pupation depth of Rhagoletis mendax Curran (Diptera: Tephritidae) in the laboratory

Mulching can be beneficial for organic highbush blueberry production, but its effects on insect pests have received little attention. For pests that pupate in soil, depth may affect pupation success due to differences in temperature and moisture, mortality factors such as predation, or efficacy of controls such as insecticidal soil drenches. We examined how mulch type and moisture affect pupation depth for Rhagoletis mendax Curran (blueberry maggot), an important pest of blueberries. In laboratory studies, pupation depth was measured in wood waste compost, uncomposted pine needles, soil and sand, each at dry, field moisture levels and wet, 99% water holding capacity conditions. Pupation occurred more deeply but with greater variability in pine needle mulch compared to compost mulch, soil, or sand. Approximately 50% of maggots pupated on the surface of wet soil, however, maggots burrowed more deeply in wet than in dry pine needles. Moisture level did not significantly affect pupation depth in compost or sand. Some larvae unexpectedly escaped the stacks of cups used to assess pupation depth or died before forming a puparium. Less than 70% of stacks with dry pine needles contained pupae, and fewer pupae were recovered from wet than dry compost and soil. These results suggest that mulch material and/or moisture levels can have significant impacts on R. mendax pupation depth with potential implications for its management.

Utilization of pine needles as bed material in solid state fermentation for production of lactic acid by Lactobacillus strains

Pine needles, which are abundantly found as underexploited biomass in coniferous forests, are responsible for fire hazards and air pollution. Utilization of pine needles as bed material in lactic acid production with solid state fermentation (SSF) has been studied here. This investigation compared lactic acid production by pure strains of Lactobacilli, (1) L. delbrueckii(NCIM2025); (2) L. pentosus (NCIM 2912); (3) Lactobacillus sp.(NCIM 2734); (4) Lactobacillus sp. (NCIM2084); and a co-culture of the first two strains. The studies required 6 g per flask powdered dry pine needles as bed material, 2 g/L (inoculum), liquid production media based on pure glucose or whey substituted glucose, at 60, 80, and 120 g/L sugar levels, 37 oC, and an initial pH of 6.5. Co-culture attained a maximum lactic acid concentration of 45.10 g/L, followed by that of strain-1, 43.87 g/L and strain-4, 26.15 g/L, in 80 g/L pure glucose media. With 120g/L total sugar in whey-substituted media, the co-culture attained maximum lactic acid production of 44.88 g/L followed by that of strain-1, 43.67 g/L. The present experimental studies indicated better compatibility of pine needle bed with co-culture in solid state fermentation of lactic acid, which may prove to be an eco-friendly technology for utilization of biomass as well as minimizing fires in coniferous forests.

Leaf transport and retention in a high gradient stream

Abstract. To a large extent, the invertebrate fauna in wooded streams rely upon detritus inputs from the surrounding vegetation as their main food source. Conifer plantations may alter the timing and nutritional quality of leaf inputs into streams, but detritus retention may also be reduced. While it has often been assumed that conifer needles are retained less than broadleaved species, this has never been tested experimentally. This study describes the results of a leaf release experiment carried out in a small headwater stream, comparing the retention of pine needles and oak leaves (wet and dry) over a range of discharges. In addition, retention was compared before and after placing logs in the stream to examine the effect of woody debris on retention efficiency. Retention efficiency was significantly different among the three leaf types tested with wet oak leaves being most retentive, followed by dry oak leaves with dry pine needles being least retentive. Retention efficiency declined significantly with increasing discharge for all three leaf types. The addition of logs increased the retention of dry oak leaves and pine needles, but not wet oak leaves. The predominant features (stones, logs, eddies and bankside vegetation) that accounted for retention varied with discharge and the leaf type used. The results indicate that while conifer needles may be inherently less retentive than broadleaves, the presence of woody debris within the stream channel increases their retention. However, this small-scale study would need to be expanded to investigate the retention dynamics of conifer needles in plantation streams. Nevertheless, management strategies that allow the formation of woody debris accumulations in plantation streams could be valuable in enhancing detritus retention and consequently could benefit invertebrate communities. Keywords: pine needles, retention efficiency, woody debris, discharge

Forest canopy chemistry with high spectral resolution remote sensing

Abstract Forest ecosystem modelling requires information about canopy chemistry. This is usually obtained through chemical analysis and laboratory spectrometric measurements. The potential of spectrometric remote sensing was investigated with two airborne campaigns organized in 1991 with AVIRIS (Airborne Visible/Infrared Imaging spectrometer) and in 1993 with ISM (Infrared SpectroMeter) over the 'Landes’ forest (south-west France): AVIRIS covers the 400-2500 nm spectral range with 210 bands, whereas the ISM instrument is an airborne profiling spectrometer that operates in the 800-3200 nm spectral range with 128 bands. The study area consists of homogeneous parcels of maritime pines with a wide variety of ages from 2 to 48 years. Simultaneously with the airborne acquisition, foliar samples were collected in the field. These samples were chemically analysed for determining nitrogen, lignin and cellulose contents. Reflectance spectra of dried pine needles were obtained with the help of two laboratory spectro...

Simultaneous use of evolving factor analysis of fluorescence spectral data and analysis of pH titration data for comparison of the acid-base properties of fulvic acids

Three fulvic acids (fua) extracted from a Portuguese pinewood soil (dry pine needles, fual, leaf litter, fua2, and lower soil horizon, fua3) have been studied by synchronous molecular fluorescence spectroscopy (SyF) at variable pH and by potentiometric pH titrations. The number of macroscopic acid-base systems and their p K a s were calculated by analysis of the SyF-pH hyphenated data with a self-modeling curve resolution technique (evolving factor analysis, EFA). Four macroscopic acid-base systems were detected in the fulvic acid samples (with p K a s around 3.0, 4.5, 7.0 and 9.0). The concentrations of the groups responsible for the acid-base systems were calculated by a standard non-linear least squares adjustment of pH potentiometric titration curves using the p K a values obtained by EFA. The procedure detected differences between the three fua: the concentration of carboxylic groups increased from fual to fua3 but, in contrast, the concentration of the phenolic groups decreased. These results correlate well with the expected extent of humification of the samples.