Vineyard Pruning Residues Research Articles

Biomass Resources from Vineyard Residues for the Production of Densified Solid Biofuels in the Republic of Moldova

This paper explores the utilization of biomass resources derived from vineyard residues for producing densified solid biofuels in the Republic of Moldova, with the aim of quantitatively and qualitatively evaluating the residue from vine pruning, focusing on the feasibility of its use as raw material for the production of briquettes and pellets. The methodology includes the analysis of statistical data, as well as experimental investigations conducted at the Scientific Laboratory of Solid Biofuels of the Technical University of Moldova. Waste biomass samples were collected from various vineyards in the different districts of all three regions of the country, focusing on regions with significant plantations. Both quantitative and qualitative aspects of the biomass were assessed, considering the moisture content, calorific value, and ash content. It was found that about 1013 kg/ha of waste biomass is generated from the pruning of technical grape varieties with a net calorific value of 15.6 MJ/kg at a moisture content of 10 wt.% and about 1044 kg/ha with a calorific value of 16.4 MJ/kg from the table ones; both with an average ash content of 3 wt.%. The results indicated that vineyard pruning residues in the Republic of Moldova could provide a substantial biomass source, with an estimated total energy potential of approximately 370 TJ/y (80% located in the Southern region); they also highlighted the need for technological advancements and quality assurance procedures through which to ensure the efficiency and sustainability of biofuel production. The conclusions emphasize the numerous benefits of utilizing viticultural residue, both economically and ecologically, contributing to the sustainable development of the viticulture industry in the Republic of Moldova, as well as environmental protection.

Determination Size Distribution of Shredded Vineyard Pruning Residues According to Variety

In this study, it was aimed to determine the particle size distribution of vineyard pruning residues shredded with a shredding machine according to grape variety. Pruning residues of three grape varieties, respectively, Boğazkere, Öküzgözü and Şire were used for the experiments. For shredding experiments, a wood chipper machine powered by a 15 HP thermal engine was used. Trials were conducted at three different engine speeds (1500 rpm, 2000 rpm, 2500 rpm). There are 3 shredding blades on the chopper unit of the machine. The blades are driven by gasoline engine with the a belt and pulley system. The study was carried out at three different blade rotation speed. Particle size distribution was determined for each rotation speed and grape variety. Sieves with diameters of 12.5-50 mm were used to calculate the particle size distribution. According to the results, an inverse relationship was obtained between the blade rotation speed and the size length of the shredded branches for all varieties. The ratio of the size and length of the chopped/chopped residues passing through the sieves varied according to the blade speeds. Also, the significant difference were found between varieties (p

Implementation of a Circular Bioeconomy: Obtaining Cellulose Fibers Derived from Portuguese Vine Pruning Residues for Heritage Conservation, Oxidized with TEMPO and Ultrasonic Treatment

Inspired by the principles of the circular economy, using vineyard pruning residues as a source of raw materials for producing nanocellulose is a promising approach to transforming vineyard resources into value-added products. This study aimed to obtain and characterize cellulose and cellulose nanofibers from such sources. The cellulose collected from different fractions of micronized stems (500, 300, 150 μm, and retain) of vines was submitted to autohydrolysis and finally bleached. Soon, it underwent treatment via (2,2,6,6-tetrametil-piperidi-1-nil)oxil (TEMPO) oxidation and ultrasonic to obtain nanocellulose fibers. The cellulose films were obtained at a microscale thickness of 0.05 ± 0.00; 0.37 ± 0.03; 0.06 ± 0.01 e 0.030 ± 0.01 mm, with the following particle size: 500 µm, 300 µm, 150 µm, and retain (<150 µm). The bleaching efficiency of the cellulose fibers of each particle size fraction was evaluated for color through a colorimeter. In addition, the extraction of cellulose fibers was assessed by infrared with Fourier transform, and size and shape were assessed by microscopy. Differential scanning calorimetry and X-ray diffraction were performed to confirm the thermal and crystalline properties. Combining autohydrolysis with a bleaching step proved to be a promising and ecological alternative to obtain white fractions rich in cellulose. It was possible to perform the extraction of cellulose to obtain nanocellulose fibers from vine pruning residues for the development of coatings for the conservation of heritage buildings from environmental conditions through an environmentally friendly process.

Properties of organic compost from vineyard pruning residues and wine lees and evaluation when used in substrates for grapevine saplings under various irrigation treatments

Properties of organic compost from vineyard pruning residues and wine lees and evaluation when used in substrates for grapevine saplings under various irrigation treatments

Valorising Agricultural Residues through Pelletisation

The agricultural sector and its related production chains are good sources of residual biomass. Olive and vineyard pruning residues are present in high quantities in Italy. The limited bulk and energy densities of these biomass materials affect the harvesting and logistic costs, limiting energy and environmental sustainability. Pelletisation is the most efficient process for increasing bulk and energy densities. This study evaluates the pelletisation process of olive and vineyard prunings, pure, or blended with variable quantities of spruce sawdust. A 15 kW pelletisation system was chosen, in line with production at the farm level. The most important quality parameters of the produced agripellets were analyzed. The results of this investigation suggest that blending could valorize other biomass materials less suitable for pelletisation and reach the pellet quality required by Italian technical standards. The addition of pruning residues to spruce sawdust leads to an improvement in durability. Spruce sawdust pellets have a durability value of 78.4%. Adding 20% of olive prunings (S80O20) increases this value to 92.2, while adding 20% vineyard prunings (S80V20) increases this value up to 90.3. The addition of 20% of pruning residues significantly increased the length and decreased fines.

Comparison of Ash Content in Vineyard Pruning Residues from Moravian Region

Abstract This study presents the thermogravimetric analysis results of various samples of vineyard pruning residues from Rakvice Stand in the Moravian viticultural region. The samples of Welschreisling, Grüner Veltliner, Gewürztraminer, and Palava were investigated in several heating-isotherm steps. Based on the results, three of these samples were found to not meet the conditions for the B category (≤3%) according to the EN ISO 17225 in terms of ash content. Only the Palava sample showed 2.76% of ash content in dry matter, which makes it suitable for technological applications, such as combustion in small residential biomass boilers. Considering the other samples, the results indicate that it is more appropriate to combust them as a part of mixture with added content of different wood biomasses.

Pelletizing of vineyard pruning residues and determination of pellet physical properties

Amaç: Her yıl üzüm bağlarından önemli miktarda bağ budama artıkları ortaya çıkmaktadır. Bu artıklar önemli bir enerji potansiyeline sahiptir. Bu çalışmanın amacı bu artıkları pelet olarak değerlendirmektir.
 Materyal ve Yöntem: Öğütülmüş bağ budama artıkları, iki farklı nem içeriğinde (yaklaşık %11 ve %15) ve üç farklı parçacık boyutunda (2, 4, 6 mm) pelet makinesinde çevre şartlarında peletlenmiştir. Peletlerin kalitesini belirleyen hacim yoğunluğu, parça yoğunluğu, mekanik dayanıklılık direnci, basınç direnci ve nem alma durumu gibi fiziksel özellikleri belirlenmiştir. Ayrıca, pelet makinesinin üretim kapasitesi ve enerji tüketim değerleri ölçülmüştür.
 Araştırma Bulguları: Üretilen peletlerin fiziksel özellikleri materyal nem içeriği ve parçacık boyutuna bağlı olarak hacim ve parça yoğunluğu ortalama 696 kg m-3 ve 1262 kg m3, mekanik dayanıklılık direnci %91 ve gerilme direnci 2.36 N bulunmuştur. Ortalama üretim kapasitesi ise 45 kg h-1 olarak ölçülmüştür.
 Sonuç: %11 ve %15 nem içeriğinde bağ budama artıklarından kaliteli peletler üretildi. Bu artıklardan elde edilen peletlerin fiziksel özellikleri literatür verileri ile uyumlu olduğu tespit edilmiştir.

Environmental Sustainability of Heating Systems Based on Pellets Produced in Mobile and Stationary Plants from Vineyard Pruning Residues

The impact of heat production from vineyard pruning pellets has been evaluated in this paper. The study considers two different systems: the first one based on a mobile pelletizer (PS1) and the second one based on a stationary pellet plant (PS2). The analysis conducted is from “cradle to grave”; the systems under analysis includes pruning harvesting, transport to storage area, pelletization (mobile system or stationary production plant), transport to consumer and combustion. The functional unit selected is 1 MJ of thermal energy produced. The impact assessment calculation methods selected are Eco-Indicator 99 (H) LCA Food V2.103/Europe EI 99 H/A with a midpoint and endpoint approach, and ReCiPe Midpoint (H) V1.10. Considering Life Cycle Assessment results, Eco-indicator shows a total impact of 4.25 and 4.07 mPt for mobile pelletizer and stationary pellet plant, respectively. Considering the three damage categories, PS1 has values of 2.4% (Human Health), 3.8% (Ecosystem Quality) and 17.3% (Resources), more impactful than PS2. Contribution analysis shows that direct emissions are the major damage contributor, followed by wood ash management. From a comparison between the baseline scenario and a scenario with an avoided product (wood ash as a standard potassium fertilizer), PS1 and PS2 with an avoided product approach are 41% and 40% less impactful than in the baseline scenarios. When testing the impact of mobile pelletizer while considering transportation as a factor, a reduction of distance for pellet has been evaluated. Reducing the distance from 100 to 10 km, the total impact of PS1 almost reaches the impact of PS2 with a difference of around 4.6% (Eco-indicator 99 method). The most impactful processes are pellet production, direct emissions and ash management, while a less impactful factor is the electricity consumption. Transportation shows the lowest impact. Considering the ReCiPe impact calculation method with a midpoint approach, the results confirm what was found with Eco-indicator 99; the PS1 shows a slightly higher impact than PS2.

Sustainability of using vineyard pruning residues as an energy source: Combustion performances and environmental impact

Open burning of agricultural waste is still a common practice as it is a rapid method for waste disposal, although natural biomass, including agriculture residues, can be exploited as a renewable energy source. We assessed the viability and sustainability of using vineyard pruning residues, as wood chips, for energy conversion. Wood chips, obtained from vineyards in the Prosecco DOCG region (Italy), were characterized in terms of chemical composition, calorific value, ash content and humidity. Combustion tests were performed in a medium-size biomass boiler (maximum power 500 kW) to assess the viability of the approach in terms of sustainable steady-state combustion. Primary emissions of both macro- and micro-pollutants were measured to assess the environmental impact. An analytical method was purposely developed for the determination of polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) in three matrices: fly ashes, condensate and gas. The results showed that vineyard pruning residues can be used for energy conversion in medium- and large-scale biomass boilers. Primary emissions of measured pollutants were all below limit values set by current European legislation except for particulate matter, for which current available abatement technologies are required to contain emissions, thus making the use of vineyard pruning residues unsuitable for combustion in domestic appliances where such technologies are not installed. Bottom ashes produced during combustion were also characterized to assess whether they can be recycled in the vineyard as soil amendments/fertilizers. Copper content in combustion ashes exceeded limit values for ashes to be used as fertilizers in agricultural fields for some European countries but not for others, indicating that ashes may need to be disposed as waste.

Emissions of heating appliances fuelled with agropellet produced from vine pruning residues and environmental aspects

Abstract Vine is one of the most widespread crop cultivated in Italy. The management of these residues is linked to an additional cost for the operator and determines environmental issues mainly due to open field combustion. A better exploitation of these residues could be the use for thermal energy production in residential heating devices fuelled with pellet. In the present work vineyard pruning residues were collected, pelletised, then characterised according to the standard for solid biofuels. Combustion tests were performed in a 150 kWth boiler fuelled with pruning pellet and the related TSP, CO, NOx emissions were measured. In order to make a comparison with the open field combustion emissions of the vineyard pruning residues, simulation tests were conducted at lab scale. Open field emissions are up to 120 times for CO emission and 30 times for TSP more than the boiler emission. Results highlighted that by avoiding open field combustion and using this residual biomass for energy production, a significant reduction of environmental pollution together with an increase in renewable energy production can be obtained. The results can be useful as support for policy makers engaged in developing the strategy for the promotion of renewable energy and air quality improvement.

Vineyard pruning residues pellets for use in domestic appliances: a quality assessment according to the EN ISO 17225

Nowadays many types of biomass are studied to satisfy the increased demand of renewable energy based on pellet combustion. However, only a few biomasses fulfil the high quality standard required for pellet used in domestic appliances. European and International standards in force define this quality of non-industrial use of pellets in term of the origin of biomass, physical, mechanical and chemical parameters. Vineyard residues are a worldwide potential source of energy but their compliance to be used in domestic pellet stoves has not been yet proven according to the new standards in force. In order to meet this need, this study makes an exhaustive characterisation of vineyard based pellets manufactured from residues of Prosecco (Glera variety) vineyards, assessing both the quality of biofuel and its behaviour during combustion in a domestic pellet stove. The quality of biofuel has been evaluated according to the in force standards for wood and non-woody pellets. The results show that vineyard pellets do not meet the type B quality standards required for non-industrial use of wood pellet mainly because of the high amount of ash content (>2%) and the high amount of copper (>10 ppm) but they fulfil the specifications of the type B non-woody pellets. Furthermore, during combustion test of vineyard-based pellet the high emission of CO indicates incomplete combustion; and vineyard- based pellet NOx emissions are more than double compared to those obtained during the control tests, confirming that the analysed vineyard-based pellets are unsuitable, as they are, for use in traditional pellet stoves.

Evaluation of the characteristics of vineyard pruning residues for energy applications: effect of different copper-based treatments

The role of biomass for increasing renewable energy sources mix is considered fundamental, despite some negative environmental impact of first-generation biofuels. The use of biomass obtained in a more sustainable way, as represented by agricultural wastes, should be favoured. The Mediterranean area and Italy in particular offer a large amount of vineyard pruning residues that can be converted into bioenergy. Since vineyards are exposed to treatments based on copper (Cu) and zinc, these metals last in wood residues during pruning and accumulate in the soil. In this study an evaluation of the concentrations of copper and other heavy metals in grapevine pruning wastes, when treated with common plant protection products, was carried out. The study was also extended to the soil, being potentially mixed to the biomass in the case of mechanical collection of pruning residues. The grapevine residues free of impurities that were collected during this study have typical values of copper in pruning wood, varying from 8.5 mg kg<sup>–1</sup> when treated with low Cu product, to 19.2 mg kg<sup>–1</sup> when treated with high Cu product. It was observed that contaminations during pruning with soil could increase the amount of copper in the residues. More in detail, every percentage point of soil that winds up on pruning residues involves an increase of 1 mg of Cu every kg of biomass. For this reason, we recommend the use of appropriate systems for the harvest of grapevine residues, particularly mechanical systems that avoid soil lifting. Moreover, we suggest the use of pruning residues preferably in large-scale power plants with appropriate emission filters instead of small-scale domestic boilers.

Delignification of vineyard pruning residues by alkaline peroxide treatment

Vineyard pruning residues were subjected to alkaline peroxide treatment for delignification. Experimental conditions maximizing lignin removal were determined by using Box–Behnken statistical experiment design. NaOH/Biomass, H2O2/Biomass and retention time were chosen as independent variables and percent lignin removal was the objective function. Experiments were done at constant Solid/Liquid ratio of 0.1 (w/w) and 135°C. All parameters were found to have significant effect on lignin removal. Complete delignification was obtained in 120min at a NaOH/Biomass ratio of 1.10 and a H2O2/Biomass ratio of 0.65. The solid residue consisted of 95% total carbohydrate indicating significant carbohydrate enrichment after complete delignification.

Ethanol production from vineyard pruning residues with steam explosion pretreatment

Second generation bioethanol is a renewable fuel that can be produced from cellulosic biomass through hydrolysis and fermentation based processes. Vineyard pruning residues constitute a potential lignocellulosic substrate for bioethanol production, since they have high sugar content and are a renewable, cheap, and readily available feedstock. In this work, vineyard pruning residues were firstly characterized to determine the content of ash (3.0 ± 0.0%), extractives (12.2 ± 0.0%), acid insoluble lignin (31.6 ± 2.2%), glucan (28.4 ± 0.9%), XMG (14.4 ± 0.4%), arabinan (2.6 ± 0.2%), and acetyl groups (3.9 ± 0.8%) using the standard laboratory analytical procedures for biomass analysis provided by the National Renewable Energy Laboratory. Vineyard pruning residues were then pretreated in a steam explosion pilot unit at severity of 3.83, 4.24, 4.56, and 4.69. The two pretreated water insoluble fiber fractions, characterized by the highest cellulose recovery yield, were tested for ethanol production by separate hydrolysis and fermentation process. The composition of pretreatment products, the enzymatic digestibility, and the ethanol yield were analyzed. Results show that the maximum ethanol yield (8.9 g ethanol/100 g raw material) is obtained after pretreatment at a severity of 4.24. © 2014 American Institute of Chemical Engineers Environ Prog, 34: 802–809, 2015

Characterization of chemical–physical, structural and morphological properties of biochars from biowastes produced at different temperatures

Biochar production from biowastes (e.g. digestate) is currently one of the more innovative and unexplored fields of research. A complete characterization of these materials, also according to the production temperature, would be a key tool to assess their potential use as soil amendments. For this purpose, five feedstocks (sewage sludge, municipal organic waste, cattle manure and silage digestates, poultry litter and vineyard pruning residues) were pyrolyzed at different temperatures. Structural and morphological transformations of biomasses during heating were followed by using FT-IR, scanning electron microscopy (SEM) and hyperspectral enhanced dark-field microscopy, a novel technique that provides both spectral and spatial information in one measurement. In addition, biochar microstructure (i.e. surface area and pore size distribution) using CO2 and N2 adsorption isotherms was investigated. Specific density was also analysed by a helium pycnometer. Biochars exhibited considerable chemical, structural and morphological differences depending on temperature and feedstock type. Moreover, specific density and surface area increased with the temperature. In particular, heating was able to produce a sharp increase of mesopore and micropore volume especially at 450 and 550 °C, but with different intensities for each feedstock. Thanks to the hyperspectral analysis, distinctive spectral patterns depending on the biochar chemical composition as well as the spatial distribution of the components were found. The results demonstrated that, from a physical–chemical point of view, it is not possible to identify an “ideal” biochar able to improve both soil nutrient content and structure. On the contrary, depending on feedstocks and temperature, each biochar exhibits specific features that would make it suitable for a specific purpose.

Vineyard residues as a fuel for domestic boilers in Trento Province (Italy): Comparison to wood chips and means of polluting emissions control

Vineyard pruning residues are a potential resource of biomass for energy. Nevertheless the possible presence of agrochemicals in this fuel could entail negative environmental consequences during its combustion. In order to verify its sustainability for energy production, a case study was conducted: biomass from common and organic vineyards in Trento Province (Northern Italy) was collected, analyzed, and burned as comminuted fuel in a 180MJ domestic boiler equipped with a micro electrostatic filter; wood chips and pellets produced with similar raw material (vineyard residues and spruce wood) were used as reference. Flue gases composition was monitored with particular attention to heavy metal contamination.The results, to be considered as preliminary, show that vineyard residues had higher emissions compared to the remaining fuels, including organic vineyard residues, but always within the limits prescribed in Italy. In terms of total heavy metal emissions no significant differences could be detected among the tested fuels. The electrostatic filter proved to be effective in the reduction of total fly ash emissions as well as the use of pelletized biomass.

Production and quality of biomass fuels from mechanized collection and processing of vineyard pruning residues

Vineyards cover about eight millions of hectares worldwide and their annual pruning generates a large amount of ligno-cellulosic biomass, potentially available for industrial and energy use. Commercial pruning residue harvesters are now available, which may allow cost-effective recovery. The study aimed at determining the quantity and the quality of pruning residues potentially derived from vineyard management. Data were obtained from 17 fields in Northern and Central Italy. Fields were harvested with seven different machines. The experimental design adapted to the necessities of field trials, but was adequate for testing the main sources of variability. Net residue yield varies around 1 oven dry tonne per hectare, with minor differences between grape varietals and harvesting technologies. Losses are still high, and are generally related to ineffective management techniques. Moisture content at harvest varies between 40% and 45%, whereas the higher heating value is slightly lower than that of forest fuels. Comminuted vineyard residues are unsuitable for firing residential boilers, due to the frequent presence of oversize and/or undersize particles. The application of pesticides does not result in any significant contamination with noxious chemicals, because these products are almost completely weathered before residues are recovered. In wine-producing regions, the recovery of vineyard pruning residue may represent a substantial source of industrial bio-fuel.

Harvesting vineyard pruning residues for energy use

Comparative tests of 4 systems for harvesting vineyard pruning residues were carried out using 1) a square baler; 2) a round baler; 3) a comminuter (or shredder) with drop-down re-usable containers (big bags); 4) a comminuter with built-in dumping bin. All machines were light enough for towing or carrying behind compact vineyard tractors. The machines were tested in Central Italy, on 10 ha of hill vineyard, with slope gradients ranging from 20 to 35%. The tests included forwarding the processed residue to a central storage place 3 km away. Harvesting–processing productivity ranged from 1.1 to 1.7 t per scheduled machine hour (SMH), including all delays. Calculated harvesting–processing costs varied between 19.7 and 32.3 € t−1, but increased from 53.0 and 105.2 € t−1 when forwarding the residues to a central collection point was included. The additional cost of residue management could amount to about 25 € t−1 (50 € ha−1 for 2 t ha−1). The commercial viability of recovering vineyard pruning residue also depends on the eventual redistribution of the savings accrued on residue management. The studied systems offered different products: systems 1 and 2 produced bales, which are easier to store, but are not suited for the feeding of automated furnaces, unless they are further processed into chips. However, systems 3 and 4 produced chips, which are more difficult to store but can be fed to automated furnaces without any further processing.