Wooden Pallets Research Articles

A perspective on the reverse logistics of plastic pallets in Canada

In this paper, the reverse logistics of plastic pallets in Canada, particularly in Nova Scotia, is investigated using different methods, including reviewing the literature and searching appropriate databases. Information such as the typical supply chains of plastic pallets, and the manufacturing processes of these products is gathered and analyzed. In addition, the best practices for the reverse supply chains of plastic pallets are identified and analyzed with a focus on recovery options, such as reusing, remanufacturing, and recycling. In addition, we find and analyze strengths, weaknesses, opportunities, and threat factors related to a specific company that is active in the wooden pallets industry and is establishing a plastic pallet reverse logistics system. Furthermore, we provide an optimization model that determines the best locations in a pallet reverse logistics network. Finally, managerial insights and recommendations are provided based on the analysis. The results of this paper have economic and environmental benefits for companies that are interested in the reverse logistics of plastic pallets.

Flint Goodridge Hospital and Black Health Care in Twentieth-Century New Orleans

Flint Goodridge Hospital and Black Health Care in Twentieth-Century New Orleans

Catalytic cracking of ethylbenzene as tar surrogate using pyrolysis chars from wastes

This paper aims at studying the catalytic activity of waste-derived chars for the reforming of a tar compound (ethylbenzene), and to identify the relationships between the modification process, the physicochemical properties and their resulting catalytic behaviour. Two chars were produced by pyrolysis: (1) used wood pallets (UWP), and (2) a mixture of food waste (FW) and coagulation-flocculation sludge (CFS) from wastewater treatment plant. Two chemical-free modification processes were separately applied to the pyrolysis chars: a gas phase oxygenation at 280 °C, or a steam activation at 850 °C. At 650 °C, the ethylbenzene conversion due to thermal cracking was significantly increased by the catalytic activity of the chars (from 37.2 up to 85.8%). Ethylbenzene was decomposed into six molecules: hydrogen, carbon dioxide, ethylene, benzene, styrene, and toluene. Cracking, oxidative dehydrogenation, and hydrogenolysis reactions were involved in the decomposition mechanism of ethylbenzene. The catalytic efficiency of the char was also discussed based on the energy transferred from tar to syngas during tar cracking reactions. The characterization, performed with SEM, XRD, Raman, XRF, BET and TPD-μGC, evidenced that the presence of mineral species in the metallic form strongly increased the syngas production and quality by catalysing aromatic-ring opening reactions and Boudouard reaction. The oxidation of mineral species, occurring during the oxygenation process, decreased the char efficiency, while rising SBET increased the syngas production for UWP-based chars. This study demonstrated that waste-based chars were efficient catalysts to convert the lost energy contained in tar into useful syngas, thus increasing simultaneously the syngas yield and quality.

Use of the Energy Potential of Organic Waste during its Incineration at Recycling Facility

To develop recommendations for improving the efficiency of the use of resource potential of organic waste, studies were carried out on the process of their thermal treatment using the example of plant manufactured by company Wellons type 2D6C8.AO. The plant is operated at one of the enterprises of the pulp and paper industry and is designed to generate process steam both by burning primary gas fuel and by using as a fuel mixture different types of organic waste (bark and wood waste, wood chips and sewage sludge). Based on the results obtained, the criteria for estimate the quality of fuel mixture: ash content (not more than 5 %), humidity (not more than 58 %), calorific value (not less than 4000 J/g), homogeneity of the component and fractional composition of the fuel mix (grain size not more than 25–50 mm) were worked out. Taking into account the developed criteria, the optimum composition of fuel mixture was determined (bark and wood waste 70–80 %, pulp and paper sludge 20–30 %, wood chips 4 %). As the main measures to reduce and stabilize the humidity of the fuel used for combustion, the introduction of dry debarking of wood, preliminary mechanical dewatering of the pulp and paper sludge, additional dosing in the main waste stream of waste formed in auxiliary industries (wooden pallets, boxes, paper scrap, etc.) is recommended. The introduction of the developed measures will prevent the disposal of waste in the environment and minimize the impact of the landfills on the geosystems.

Collections Access and Custom Storage Solutions at the Smithsonian’s Museum Support Center

The National Museum of Natural History is committed to long-term stewardship of collections and to supporting their use by scientists and the general public. This stewardship role is unique among other US natural history museums. As the nation’s natural history museum, the National Museum of Natural History has a mandated commitment to conserve and protect its collections in a manner that will assure their continued accessibility by future generations and maintain the National Museum of Natural History mission. A significant number of objects from the National Museum of Natural History are permanently stored at the Museum Support Center in Suitland, MD. This space not only includes collections from the National Museum of Natural History (NMNH), but also the Museum Conservation Institute (MCI), the National Museum of American History (NMAH), the Hirshhorn Museum and Sculpture Garden (HMSG), the Freer Sackler Gallery (FSG) and the National Museum of African Art (AfA) as well as several other museums. In terms of collections access and use, the museum support center has a team, Collections Support Services (CSS), dedicated to collections’ long-term care and preservation. Collections Support Services provides access and support for the 730,000 square feet of collections housed at MSC. CSS staff perform a variety of technical and labor tasks related to the cleaning, preparation, packing, transport, unpacking, and permanent storage of objects and specimens. This includes building custom aluminum pallets for oversized objects and whale skull cradles. Moreover, while the use of palletized storage is not a new concept in museum storage, the construction of Pod 4 at the Museum Support Center in Suitland, MD posed some unique challenges for the permanent storage of oversized collections. Pod 4 provides continuous rows of 2', 4' and 8' deep cantilevered open racking from floor to ceiling (22 feet high), and allows palletized objects to be moved and placed in the racking via forklift. Traditional wooden pallets are unacceptable by archival standards, as they are acidic by nature, bulky, heavy, not fire-retardant, and prone to pest infestation. Collections Support Services circumvented these issues by establishing an innovative system of customized aluminum pallets for collections’ long-term care and preservation. These pallets are durable and lightweight, and must pass several quality control tests that include dropping and jarring. They are also designed with multiple functions in mind for ease of use, storage, transport, and maintenance.

Blast loading of concrete pipes using spherical centrically placed C-4 charges

The Norwegian Public Roads Administration has initiated a large research project on a potential ferry-free coastal highway route E39 from Trondheim to Kristiansand. Parts of this route involve crossing somewide and deep fjords, where one of the suggested crossing alternatives is a Submerged Floating Tunnel (SFT)built in concrete. A major concern regarding an SFT is internal blast loading from accidents involving gas orfuel tankers, or from terrorist attacks. To assess the performance of tubular concrete structures exposed to blastloading, 1760 mm long plain concrete pipes with an internal diameter of 200 mm and pipe wall thickness of41 mm were loaded by spherical C-4 charges of various sizes up to 25 g. Pressure sensors in different directionsequidistant from the charge location recorded the blast pressure, while two high-speed cameras captured theevents. Using mass produced commercial off-the-shelf pipes ensures consistent geometry and material proper-ties. A wooden pallet was used as support for the pipes, and an electrically initiated blasting cap was used todetonate the C-4. A charge size of at least 13 g C-4 was needed to breach the pipe wall. Larger charge sizescaused longitudinal cracks and broke the pipe into oblong pieces. The test results were used for comparisonwith simulations using the explicit finite element solver EUROPLEXUS, intended for fast transient dynam-ics involving fluid-structure interaction. Both purely Lagrangian simulations and fully coupled fluid-structureinteraction simulations were carried out. While the former method is more efficient computationally, the lat-ter approach accounts for reflections and the confinement of the pipe. It can be difficult to predict the exactcharge size where through-thickness cracking occurs, but the qualitative results were encouraging for furtherwork. When accurate simulations of the experiments are obtained, the simulations will be extended to a fullcross-section of a submerged floating tunnel.

A Strategic Orientation toward Entrepreneurship: Implications for Pallet Manufacturer Performance

Abstract Leaders in the wood pallet industry have faced numerous trends over the past few decades that have challenged their ability to maintain success without adopting new business models and innovations. Past literature would predict that industry managers who instill entrepreneurial processes such as innovation, risk-taking, and proactiveness into their operations should be better equipped to identify, positively react to, and take advantage of changing environmental conditions. Firms that emphasize such processes are described as being strategically orientated toward entrepreneurship. The objective of this study was to determine whether pallet manufacturing firms that exhibit entrepreneurial processes are more successful than those that do not. As an example of how an entrepreneurial orientation might influence business operations, this study also analyzed revenue-generating methods of managing wood waste. Data for the study were collected from executives of North American pallet manufacturers. Findings suggest pallet firms that continually work to improve their products and services, frequently make decisions that involve risk, and proactively seek out new opportunities have higher performance than firms that do not. Furthermore, manufacturing firms that monetize waste products exhibit greater proclivity for entrepreneurial processes than firms that pay to dispose of or give away wood waste. Results are discussed and potential implications for managers in the industry are provided.

H2S removal from syngas using wastes pyrolysis chars

Pyrolysis chars from wastes were investigated as sorbents for H2S removal from syngas. The H2S removal tests were performed at ambient temperature in various dry gas matrices (N2, Air, Syngas) to study the effect of the gas composition on the adsorption efficiency. Two chars were produced by the pyrolysis of: used wood pallets (UWP), and a 50/50% mixture of food waste (FW) and coagulation-flocculation sludge (CFS). The chars were functionalized by low-cost processes without chemicals: gas phase oxygenation and steam activation. Activated chars were the most efficient materials due to their large specific surface area, alkaline pH, basic O-containing groups and structural defects in graphene-like sheets. Raman analysis evidenced that inherent mineral species (especially Ca and Fe) increased the H2S removal efficiency by promoting the formation of metal sulfide and metal sulphate species at the char surface. Mesopores lower than 70 Å were revealed to be important adsorption sites. Under dry Syngas matrix, the chars remained efficient and selective toward H2S removal despite the presence of CO2, while O2 in the Air matrix decreased their removal capacity due to the formation of sulfur acid species. The most efficient material was the steam activated char from FW/CFS, with a removal capacity of 65 mgH2S.g−1 under dry syngas. This char was proved to be completely regenerated with a thermal treatment under N2 at 750 °C. This study demonstrated that activated chars from food waste and sludge could be used as eco-friendly, affordable, and selective materials for syngas desulfurization even under dry atmosphere.

Mejora del proceso de fabricación de estibas de madera. Un caso de estudio

Introducción: el artículo muestra los resultados del proyecto de investigación aplicada sobre “Diseño de mejora al proceso de fabricación de estibas de madera a través de herramientas para el incremento de la productividad. Caso: sector maderero”, desarrollado en la Fundación Universitaria Tecnológico Comfenalco, Cartagena, Colombia (2014). Su objetivo fue generar y aplicar acciones de mejora al proceso productivo de la empresa estudiada a partir de herramientas propias de la ingeniería industrial que permitieran un mejor uso de recursos. Metodología: se aplicaron métodos y metodologías para el incremento de la productividad, como el estudio de métodos y tiempos y la metodología de 5S, una guía para implementar un programa de producción más limpia pml y para el cálculo de rendimiento de la materia prima. Resultados: se estandarizó y mejoró el proceso productivo a partir del estudio de métodos y 5S, se implantó un estándar razonable de producción para empresa y trabajadores, se evaluó una metodología para calcular rendimientos de la madera y se desarrolló una propuesta para implementar un programa de pml, cuyos lineamientos mejoraron las prácticas operativas. Conclusión: no medir un proceso es tan grave como medirlo erróneamente; esto puede conducir a implantar estándares incumplibles o muy laxos, así como a un clima laboral que genera bajos niveles de productividad debido a los niveles de satisfacción de los empleados por exigencias inadecuadas o al relajamiento de los empleados.

Life Cycle Inventory Analysis of the Wood Pallet Repair Process in the United States

SummaryThis study developed gate‐to‐gate life cycle inventory (LCI) data for the repair of 48 by 40 inch (1,219 by 1,016 millimeter [mm]) stringer‐class wood pallets in the United States. Data were collected from seven wood pallet repair facilities. Approximately 1.98 FBM (foot, board measure) (4.67E‐03 cubic meters) of lumber were used for repairing each 48 by 40 inch (1,219 by 1,016 mm) stringer‐class wood pallet, the majority (97%) recovered from damaged pallets received by the pallet repair facilities. Repair equipment powered by electricity made the largest contribution to greenhouse gas (GHG) emissions. Steel nails used for the pallet repair had the largest contribution to GHG emissions among the material inputs, while use of recovered lumber yielded the largest GHG emissions credits. Overall, the repair process for a 48 by 40 inch (1,219 by 1,016 mm) stringer‐class wood pallet had GHG credits rather than a positive GHG emission due to the GHG offsets from co‐products.

New Trends in Cotton Ginning & Cotton Seed Processing

The optimum utilization of all ingredients of cotton i.e. fibre, cotton seed, cotton stalk has become the necessity for survival in the competitive field of cotton growing and processing. The reduction of electrical power cost and to mechanize the operations in a way that manpower component is reduced to the minimum for complete cotton value processing chain has become necessity due to scarcity of manpower and increase in the price of electricity rates in different countries. The continuous efforts are being made to address these issues by the manufacturers and scientific community and various new equipments/systems have been introduced in the recent year in the journey of modernization/improvement of various operations in the cotton ginning and cotton seed processing. The goal is to achieve the optimization in the following areas: 1. The cotton fibre will be ginned in a way that it retains best natural fibre parameters i.e. maximum length, natural luster, and other natural parameters as they are available on the cotton boll when it is grown on plant in the field. 2. To fully utilize the various components of seed cotton i.e. cotton lint, cotton seed, hull, kernel, and oil. 3. To fully utilize the cotton stalk etc. to make various items such as wood pallets, particle boards, biogas, energy generation & compost making.

PROSES MANUFAKTUR MESIN GERGAJI KAYU UNTUK PENGRAJIN PALET KAYU

Wood saws are hand machines that small industries need. Almost all work processes through a saw machine with good results. Circular saws are not only used in timber industry, but also in the carbuery industry, by plumbing, construction experts, loggers or gardenists. In any hobby there are wearing it. For manufacturing process of making wood sawing machine in allotment for wooden pallet craftsman. The formulation of the problem in making this saw machine is how to manufacture wood saw process for wooden pallet craftsman and howmuch budget cost in manufacturing process of saw machine for wooden pallet craftsman. The components of the saw machine are frame, table mat, bearing, shaft, pulley transmission and V belt, while the tools and machinery used in the manufacturing process are electric welding tools, electric grinding wheels, grinding wheels, lathes, and frais machines.

Large-scale fire suppression modeling of corrugated cardboard boxes on wood pallets in rack-storage configurations

In this study, the fire growth and suppression models in FireFOAM were validated for rack-storage commodities consisting of two solid fuels, namely corrugated cardboard boxes and hardwood pallets, which are referred to as Class 2 commodity. Validation experiments included two fire-growth and two fire-suppression configurations with different rack-storage array heights (3 and 5 tiers). In the suppression study, standard-response upright ceiling sprinklers (K-factor of 160lpm/bar1/2) were used. The time-resolved chemical heat release rates obtained from the experiments were used to validate the fire growth model. The observed sprinkler activations and fire-spread patterns were used to validate the suppression model. This study identified that lateral flame spread is primarily enabled by flames impinging on the commodity's bottom surfaces. This study also showed that obstructions, such as wood pallets, can significantly impede convective and radiative heat transfer to the underside of the commodity, reducing the lateral flame spread rate. Fire-suppression modeling revealed that both surface water transport and lateral flame spread rates are important when predicting fire-suppression behavior. Therefore, as the rack-storage array height increases, so does the water transport time, which results in the fire becoming more difficult to control. Likewise, as the lateral spread rate increases, e.g., as occurs in the absence of wood pallets, fire-suppression also becomes more difficult.

Analysis of airflow and heat transfer inside fruit packed refrigerated shipping container: Part I – Model development and validation

This paper developed and validated a computational fluid dynamic (CFD) model of airflow and produce cooling inside a fully loaded refrigerated shipping container (reefer) based on porous medium approach. Wind tunnel tests were used to obtain the pressure drop characteristics of palletized stack of apple fruit. Detailed structure of the T-bar floor of the reefer and resistance to airflow of wooden pallets were included in the model. Airflow and temperature data obtained from a fully loaded, full-scale reefer were used to validate the model. The model successfully reproduced the airflow and temperature profiles inside the reefer, and in addition, high and low cooling regions were identified. At 24 h, the average temperature inside the reefer reached 2.7 °C (exp.) and 2.8 °C (numerical) from an initial 9.5 °C with an overall standard deviation of 1.70 °C (exp.) and 2.32 °C (numerical). Model predictions were acceptably accurate with an average error of 26 and 18% in predicting airflow and temperature, respectively. The absence of vent-hole on the bottom face of the packaging box caused non-uniform airflow and a highly heterogeneous cooling. These demonstrated the importance of packaging design that take into account the airflow path inside reefers.

Scaling of wood pallet fires

A method for scaling time-resolved burning behaviors of wood pallet fires has been developed. A series of validation tests was carried out in two different scales and the time-resolved heat release rates were obtained and compared. The results show that the scaling method proposed works very well. The scaling method proposed could be applied to general wood pallets.

Design and Analysis of Rubber Pallet for Industrial Application

The increase in demand to reduce packaging cost has pushed industries to look for an alternate material for packaging. At present, only wooden pallets are used as it is low cost, versatile and easy to dispose. As a result of these many trees are cut down depleting our forest reserve and increasing global warming. In this paper an attempt has been made to design and analyze the use of rubber material for pallets. Concepts are drawn based on the customer requirement and ISO standard. The rubber material is tested for its properties. Appropriate material model for rubber is selected, modelled and analyzed for deflection. Based on the results, a concept is selected for reduced deflection and weight.

Unexpected Interactions between Agricultural and Forest Sectors through International Trade: Wood Pallets and Agricultural Exports in Costa Rica

International market forces have played an increasingly important role in shaping land use dynamics through complex supply chains. In Costa Rica, the shift from a net loss to a net gain in forest cover was facilitated by forest plantations and the replacement of extensive cropland and pastures by export-oriented, high-yielding crops. However, agricultural intensification generated several feedbacks affecting forests. We analyzed the interactions between Costa Rica’s agricultural and forestry sectors associated with the use of wood pallets for commodity exports over 1985–2013. Wood pallets for growing agricultural exports created a demand for domestic tree plantations. The annual land demand for tree plantations to produce these wood pallets increased by 669%, reaching 17,606 ha in 2013 and representing 28% of the increase in demand for cropland for agricultural exports over 1994–2013. Wood supplied from plantations failed to fully substitute for wood from natural forests, only allowing for a relative substitution and preventing a major sparing of these forests. The dominant use of wood from plantations for production of low-value pallets de-incentivized investments in sustainable plantations. We showed that, beyond the typical interactions between agriculture and forestry through direct competition for land, international trade generated unexpected feedback where agricultural activities and supply chains affected forestry by triggering new demand and profound changes in forestry management. Land systems behave as complex systems, calling for integrated approaches to study the outcomes of forest conservation, reforestation programs, and development of land-based businesses.

Multi-scale characterisation of chars mineral species for tar cracking

Syngas from thermochemical conversion of waste or biomass is a renewable energy carrier that may contain pollutants – such as tar – that should be removed before further syngas utilisation. Chars have proved to be promising catalysts for tar cracking, but the influence of the physico-chemical properties on their reactivity is still unclear. This work aimed to better understand the structure and the composition of the mineral species of pyrolysis char, as well as their catalytic role in tar cracking. For this purpose, a characterisation of the minerals has been performed at bulk, surface (studied at micro and nano-scale) and crystallite scale. Pyrolysis chars were produced from wastes generated on cruise ships – namely used wood pallets (UWP), food waste (FW) and coagulation flocculation sludge (CFS) – having different mineral amount and content. Ethylbenzene was used as surrogate of light aromatic hydrocarbons in a tar cracking process. The results showed that ethylbenzene was converted into lighter gases meaning that the chars were efficient for this. Ethylbenzene conversion at 650°C was found to be significantly higher with the char from a mixture of sludge and food waste (c.FW/CFS) compared to that of wood-based char (c.UWP): 71wt.% against 45wt.%, respectively. The combination of multi-scale and complementary techniques has highlighted that the higher catalytic activity of this char was mainly attributed to the mineral content. Well dispersed mineral particles with various morphologies and natures were observed on the surface of c.FW/CFS using Scanning and Transmission Electron Microscopy (SEM and TEM). Especially, Ca, Al and P were the main mineral species identified using XRFS and SEM. These mineral species in form of oxides and hydroxyapatite were considered to be the main active mineral components for tar cracking. Oxides were identified using EDX-analysis. XRD analysis highlighted the presence of crystalised particles of hydroxyapatite (Ca5(PO4)3(OH)), while Raman spectroscopy revealed that these particles were embedded in the carbon matrix.

Life Cycle Assessment of a coniferous wood supply chain for pallet production in Catalonia, Spain

In Catalonia, northwest of Spain, the forest and timber industry are an active part of the economy. About 63.5% of the territory is forested area (more than 2 million Ha), from which 60.5% is wooded land. The main activity of the timber industry is the manufacture of wood packaging using 85% of the sawnwood to manufacture pallets, which is the most common wood product manufactured in the region. In the case of Europe, around 20% of all sawnwood consumption is used for wooden pallets and packaging. This research analyzes the impact of the conifers wood supply chain for the sawnwood and pallet production, from forest operations to the gate of the production facility. The Life Cycle Assessment (LCA) methodology was applied to both products (sawnwood and pallet) using primary data provided by the industry in order to identify the most impactful points of the life cycle. Six midpoint impact categories using Recipe methodology were assessed: Climate change, Ozone depletion, Terrestrial acidification, Freshwater eutrophication, Human toxicity; Agricultural land occupation and Water depletion. Also, Cumulative Energy Demand was assessed. It was found that electricity consumption is the most impacting input in the sawnwood and pallet production, followed by pesticide used in the production. For pallet case, steel plays a key role. Possible improvements were identified with a big potential of impacts reduction. LCA results from this research can be applied for the assessment of other wood products and also to increase the knowledge and debate about the biogenic carbon sequestration of wooden products.

Temperature- and time dependency on high friction poly(styrene-co-butyl methacrylate) coated paper

For several industrial applications, high friction surfaces with low adhesion are essential. Here, a poly(styrene-co-butyl methacrylate) polymer latex is coated on paper to achieve a high static friction at the interface between a coating and e.g. a wood pallet. At this interface, the adhesion should be low enough for easy removal of objects placed on the coated paper. The static friction is measured with a custom designed and constructed frictometer and is investigated as a function of temperature from 25 to 55°C and the resting time. Furthermore, the static friction is investigated with varying coating thicknesses and coatings containing calcium based fillers. Results show that the static friction is increasing non-linearly with both temperature and resting time. Furthermore, an amount of 10wt% filler increases static friction. In conclusion, the static friction coefficient between coated paper and wood are up to 700% of uncoated paper depending on temperature and resting time.