Green Tramp Shipping Routing and Scheduling: Effects of Market-Based Measures on CO2 Reduction

Purpose The purpose of this paper is to resolve three problems in ship routing and scheduling systems. Problem 1 is the anticipation of the future cargo transport demand when the shipping models are stochastic based on this demand. Problem 2 is the capacity of these models in processing large number of ships and cargoes within a reasonable time. Problem 3 is the viability of tramp shipping when it comes to real problems. Design/methodology/approach A commodity-trade forecasting system is developed, an information technology platform is designed and new shipping elements are added to the models to resolve tramp problems of en-route ship bunkering, low-tide port calls and hold-cleaning cost caused by carrying incompatible cargoes. Findings More realistic stochastic cargo quantity and freight can now be anticipated, larger number of ships and cargoes are now processed in time and shipping systems are becoming more viable. Practical implications More support goes to ship owners to make better shipping decisions. Originality/value New norms are established in forecasting, upscaling and viability in ship routing and scheduling systems.

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A Heuristic Procedure for a Ship Routing and Scheduling Problem with Variable Speed and Discretized Time Windows

Mathematical Problems in Engineering ◽

10.1155/2014/750232 ◽

2014 ◽

Vol 2014 ◽

pp. 1-13 ◽

Cited By ~ 1

Author(s):

Krystel K. Castillo-Villar ◽

Rosa G. González-Ramírez ◽

Pablo Miranda González ◽

Neale R. Smith

Keyword(s):

Time Windows ◽

Waiting Times ◽

Neighborhood Search ◽

Scheduling Problem ◽

Computational Results ◽

Solution Quality ◽

Ship Routing ◽

Routing And Scheduling ◽

Ship Routing And Scheduling ◽

Tramp Shipping

This paper develops a heuristic algorithm for solving a routing and scheduling problem for tramp shipping with discretized time windows. The problem consists of determining the set of cargoes that should be served by each ship, the arrival, departure, and waiting times at each port, while minimizing total costs. The heuristic proposed is based on a variable neighborhood search, considering a number of neighborhood structures to find a solution to the problem. We present computational results, and, for comparison purposes, we consider instances that can be solved directly by CPLEX to test the performance of the proposed heuristic. The heuristics achieves good solution quality with reasonable computational times. Our computational results are encouraging and establish that our heuristic can be utilized to solve large real-size instances.

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The Plains CO2 Reduction (PCOR) Partnership: CO2 Sequestration Demonstration Projects Adding Value to the Oil and Gas Industry

10.2523/17089-ms ◽

2013 ◽

Author(s):

Charles D. Gorecki ◽

Edward N. Steadman ◽

John A. Harju ◽

James A. Sorensen ◽

John A. Hamling ◽

...

Keyword(s):

Co2 Sequestration ◽

Oil And Gas ◽

Co2 Reduction ◽

Oil And Gas Industry ◽

Gas Industry

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An Inside Power-plant for the Purpose of Saving Energy and CO2 Reduction

JAPAN TAPPI JOURNAL ◽

10.2524/jtappij.60.655 ◽

2006 ◽

Vol 60 (5) ◽

pp. 655-663

Author(s):

Shigeaki Obayashi

Keyword(s):

Power Plant ◽

Co2 Reduction ◽

Saving Energy

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An NADH-Inspired Redox Mediator Strategy to Promote Second-Sphere Electron and Proton Transfer for Cooperative Electrochemical CO2 Reduction Catalyzed by Iron Porphyrin

10.26434/chemrxiv.12159207.v1 ◽

2020 ◽

Cited By ~ 1

Author(s):

Peter T. Smith ◽

Sophia Weng ◽

Christopher Chang

Keyword(s):

Proton Transfer ◽

Co2 Reduction ◽

Iron Porphyrin ◽

Redox Mediators ◽

Reservoir Properties ◽

Proton Reduction ◽

Electrochemical Co2 Reduction ◽

Starting Point ◽

Rate Improvement ◽

Molecular Catalysts

We present a bioinspired strategy for enhancing electrochemical carbon dioxide reduction catalysis by cooperative use of base-metal molecular catalysts with intermolecular second-sphere redox mediators that facilitate both electron and proton transfer. Functional synthetic mimics of the biological redox cofactor NADH, which are electrochemically stable and are capable of mediating both electron and proton transfer, can enhance the activity of an iron porphyrin catalyst for electrochemical reduction of CO2 to CO, achieving a 13-fold rate improvement without altering the intrinsic high selectivity of this catalyst platform for CO2 versus proton reduction. Evaluation of a systematic series of NADH analogs and redox-inactive control additives with varying proton and electron reservoir properties reveals that both electron and proton transfer contribute to the observed catalytic enhancements. This work establishes that second-sphere dual control of electron and proton inventories is a viable design strategy for developing more effective electrocatalysts for CO2 reduction, providing a starting point for broader applications of this approach to other multi-electron, multi-proton transformations.

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CO2 Reduction to Propanol by Copper Foams: A Pre- and Post-Catalysis Study

10.26434/chemrxiv.12022623.v1 ◽

2020 ◽

Author(s):

Jennifer A. Rudd ◽

Ewa Kazimierska ◽

Louise B. Hamdy ◽

Odin Bain ◽

Sunyhik Ahn ◽

...

Keyword(s):

Carbon Dioxide ◽

Photoelectron Spectroscopy ◽

Carbon Capture ◽

Surface Composition ◽

Co2 Reduction ◽

Structural Rearrangement ◽

Copper Electrode ◽

Ex Situ ◽

X Ray ◽

Copper Electrodes

The utilization of carbon dioxide is a major incentive for the growing field of carbon capture. Carbon dioxide could be an abundant building block to generate higher value products. Herein, we describe the use of porous copper electrodes to catalyze the reduction of carbon dioxide into higher value products such as ethylene, ethanol and, notably, propanol. For n-propanol production, faradaic efficiencies reach 4.93% at -0.83 V vs RHE, with a geometric partial current density of -1.85 mA/cm2. We have documented the performance of the catalyst in both pristine and urea-modified foams pre- and post-electrolysis. Before electrolysis, the copper electrode consisted of a mixture of cuboctahedra and dendrites. After 35-minute electrolysis, the cuboctahedra and dendrites have undergone structural rearrangement. Changes in the interaction of urea with the catalyst surface have also been observed. These transformations were characterized ex-situ using scanning electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. We found that alterations in the morphology, crystallinity, and surface composition of the catalyst led to the deactivation of the copper foams.

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Graphene Supported Tungsten Carbide as Catalyst for Electrochemical Reduction of CO2

10.26434/chemrxiv.8280986 ◽

2019 ◽

Author(s):

Sahithi Ananthaneni ◽

Rees Rankin

Keyword(s):

Tungsten Carbide ◽

Electrochemical Reduction ◽

Low Cost ◽

Co2 Reduction ◽

Platinum Group Metal ◽

Reduction Reaction ◽

Metal Carbides ◽

Depth Study ◽

Reduction Of Co2 ◽

Co2 Reduction Reaction

<div>Electrochemical reduction of CO2 to useful chemical and fuels in an energy efficient way is currently an expensive and inefficient process. Recently, low-cost transition metal-carbides (TMCs) are proven to exhibit similar electronic structure similarities to Platinum-Group-Metal (PGM) catalysts and hence can be good substitutes for some important reduction reactions. In this work, we test graphenesupported WC (Tungsten Carbide) nanocluster as an electrocatalyst for the CO2 reduction reaction. Specifically, we perform DFT studies to understand various possible reaction mechanisms and determine the lowest thermodynamic energy landscape of CO2 reduction to various products such as CO, HCOOH, CH3OH, and CH4. This in-depth study of reaction energetics could lead to improvements and develop more efficient electrocatalysts for CO2 reduction. </div>

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