Benchmarking Procurement Cost Saving Strategies for Wood Supply Chains

Intense international competition pushes the actors of wood supply chains to implement efficient wood supply chain management incorporating coordinated cost-saving strategies to remain competitive. In order to observe the effects of individual and coordinated decision making, mixed-integer programming models for forestry, round-wood transport, and the wood-based industry were developed and integrated. The models deal with operational planning issues regarding production, harvest, and transport and are solved sequentially for individual cost optimization of each wood supply chain actor as well as simultaneously by a combined model representing joint cost optimization in an integrated wood supply chain. This allows for the first time, benchmarking relative cost-saving potential of the wood procurement strategies coordinated transports, integrated supply chains, satellite stockyards, and higher truck payloads within a single case study setting. Based on case study data from southern Austria, results show the advantages of an integrated supply chain with a cost-saving potential of up to 24%. Higher truck payloads reinforce this potential and enable up to 40% savings compared to the predominant wood procurement situation in Central Europe. Wood supply chain integration for Central European circumstances seems to be feasible only for a limited consortium of a few companies, for example when restricted to a wood-buying syndicate supplying several industry plants or a few large forest enterprises, especially as both groups are commonly steering wood transport on their own. Consequently, further research on the challenging task of implementing integrated supply chains using the opportunities of digitalization to realize existing cost savings potential by deepening cooperation and intensifying information exchange is needed.

Influence of the depreciation method on the wood transport cost

O transporte de madeira no Brasil, predominantemente rodoviário, representa um dos segmentos mais onerosos do setor. A depreciação, um dos custos fixos na produção florestal, é incluída na utilização e substituição de máquinas. Essa depreciação pode ser calculada por meio de diferentes métodos, e os melhores devem ser utilizados para aperfeiçoar os custos nessa área. O objetivo deste estudo foi avaliar a depreciação de um caminhão e o custo de transporte rodoviário florestal, usando quatro métodos de análise: Caires, Cole, Exponencial e Linear. Os custos de depreciação e de transporte foram determinados utilizando a planilha de simulação de custos de frete para o Transporte Rodoviário de Cargas, desenvolvida pela Agência Nacional de Transportes Terrestres (ANTT). Constatou-se que a depreciação mensal do caminhão foi de R$ 1.630,25, R$ 2.276,64, R$ 2.400,96 e R$ 2.422,40, calculada pelos métodos de Caires, Exponencial, Linear e de Cole, respectivamente. O menor custo de transporte foi de R$ 13,71, obtido pelo método de Caires, seguido de R$ 13,72, R$ 16,72 e R$ 16,92, obtidos pelos métodos Linear, Cole e Exponencial, respectivamente. Os menores valores de depreciação e custo de transporte por tonelada obtidos pelo método de Caires se devem ao fato de esse método considerar outras variáveis, além da idade atual e da vida útil da máquina, e ajustar o modelo e os coeficientes de utilização para situações específicas. Isso retrata as condições encontradas em campo, portanto gera custos próximos aos reais. A estimativa da depreciação de transporte florestal foi melhor pelo método de Caires, em todas as situações estudadas, o que evidencia a necessidade de considerar fatores de manutenção e trabalho no cálculo da depreciação. A adoção desse método também representa grande economia de recursos financeiros no longo prazo.

A One-Way Coupled Hydrodynamic Advection-Diffusion Model to Simulate Congested Large Wood Transport

An advection-diffusion model is proposed to simulate large wood transport during high flows. The mathematical model is derived from the wood mass balance, taking into consideration both the wood mass concentration and the log orientation, which affects log transport and, most importantly, wood accumulation. Focusing on wood mass transport, the advection-diffusion equation is implemented in a hydrodynamic model to provide a one-way coupled solution of the flow and of the floating wood mass. The model is tested on a large series of flume experiments, involving at least 30 logs and different control parameters (flow Froude number, log length, diameter, release point). The validation through the experimental data shows that the proposed model can predict the correct displacement of the most probable position of the logs and to simulate with a sufficient accuracy the planar diffusion of the wooden mass. Transversal wood distribution is more accurate than the streamwise one, indicating that a higher control on the longitudinal diffusion needs to be implemented.

On the applicability of loose logs driving on small rivers in modern conditions

Авторы собрали и проанализировали существующую информацию по вопросу сплава древесины по малым рекам. Приведенные данные указывают на то, что сплав по воде наиболее экономически выгоден. Рассмотрены различные аспекты влияния молевого сплава на водный объект и на популяцию рыб. Проведен анализ положительного и отрицательного воздействия, в том числе во временном разрезе. Исходя из собранной информации сделаны конкретные выводы и сформулированы рекомендации по использованию молевого сплава как наиболее выгодного и безопасного способа транспортировки леса. The authors collected and analyzed available information on the problem of loose log transport on small rivers. These data indicate that water trasnsport is the most cost effective. Various aspects of the influence of the wood transport on the water and on the fish population are considered. The analysis of positive and negative impacts, including in the context of time, was carried out. On the basis of the collected information, specific conclusions are made and recommendations are formulated for the use of loose log transport on small rivers, as the most profitable and safe method of transporting wood.

Brief communication: The curious case of the large wood-laden flow event in the Pocuro stream (Chile)

Large wood transported during extreme flood events can represent a relevant additional source of hazards that should be taken into account in mountain environments. However, direct observations and monitoring of large-wood transport during floods are difficult and scarce. Here we present a video of a flood characterised by multiple phases of large-wood transport, including an initial phase of wood-laden flow rarely described in the literature. Estimations of flow velocity and transported wood volume provide a good opportunity to develop models of large-wood-congested transport.