Volatile organic compounds (VOCs) emitted from industrial processes have high stability, low activity, and toxicity which cause continuous harm to human health and the atmospheric environment. Catalytic combustion has the advantages of low energy consumption and low cost and is expected to be one of the most effective methods to remove VOCs. At present, the selection of low cost, high activity, and durability catalysts are still a difficult problem. Industrial emissions of VOCs contain a certain amount of aromatic hydrocarbons; these substances are highly toxic substances, and, once inhaled by the human body, will cause serious harm to health. In this paper, the principle, advantages, and disadvantages of VOCs processing technology are analyzed in detail, and the catalytic combustion of aromatic hydrocarbons in VOCs is reviewed, including catalyst, reaction conditions, catalyst selection, inactivation reasons, and structure use. In addition, the deactivation effects of chlorine and sulfur on catalysts during the catalytic combustion of VOCs are discussed in detail. Finally, on the basis of literature research, the prospect of catalytic combustion of VOCs is presented, which provides influential information for further research on VOCs processing technology.
Oil spill accidents have gradually increased due to the continuous development of marine transportation and petroleum processing industries. Monitoring and managing marine oil spills present important economic, social, and practical implications in preventing offshore oil pollution and maintaining ecological balance. Unmanned aerial vehicle (UAV) has become a suitable carrier for low-altitude oil spill detection because of their fast deployment and low cost. Thermal infrared remote sensing images are used as the research object in this study. A method around histogram of gradient (HOG) features combined with a support vector machine (SVM) is proposed for identifying oil spills at sea to improve the accuracy of offshore low-altitude oil spill recognition and realize all-weather monitoring of offshore oil spills in offshore waters. Steps for extracting HOG features and basic principles of the SVM classification are first investigated. Image preprocessing is then performed on collected thermal infrared image data to produce samples. HOG features of samples are extracted, and the radial basis function is selected as the kernel function for training the SVM classifier. HOG features of the infrared image to be tested are calculated and then sent to the classifier for identifying the oil spills. In addition, the proposed method is compared with the back propagation(BP) neural network method and local binary pattern (LBP) combined with the SVM classification method for analysis. The results show that the oil film recognition method based on the HOG feature and SVM has a recognition accuracy of 91.3% in the environment of small infrared oil film samples, which is significantly better than the BP and LBP-SVM recognition methods, and obtains a shorter training time. The method proposed in this study has obvious advantages in terms of small sample size and processing efficiency, can meet the requirements of all-weather inspection of oil film pollutants by UAV in offshore port areas, and has great application potential in the field of maritime supervision informatization in the future.
22 March 2022 in International Journal of System Assurance Engineering and Management
Effective and timely collision avoidance decision support is essential for super-large vessels navigating in port waters. To guarantee the navigational safety of super-large vessels, this work proposes a collision avoidance decision support method based on the curve increment strategy with adaptive particle swarm optimization (CIPSO). Firstly, the objective function is constructed based on the multi-objective optimization method. Here, a fuzzy comprehensive evaluation (FCE)-based vessel collision hazard model and vessel speed-varying energy-loss model integrating the Convention on the International Regulations for Preventing Collisions at Sea (COLREGS) are involved. Furthermore, in response to the limitations of the PSO algorithm, which is prone to falling into local optima in the later stages of iteration, a curve increment strategy is incorporated. To improve the performance of the global optimization, it is optimized using a local followed by global search method. The iterative evolution of CIPSO is used to obtain the optimal decision value in the set domain of feasible solutions. Finally, the effectiveness and feasibility of the proposed method are verified by the numerical simulation and large vessel maneuvering simulator, which can provide collision avoidance decision support for ship pilots.
Coastal governments have been preventing and controlling pollution in the marine environment by enhancing the construction of hardware and software facilities. The dispatch of offshore oil spill cleaning materials must be upgraded and optimized to cope with repeated offshore oil leak incidents while simultaneously improving cleaning efficiency and the ability to resist oil spill hazards. Accordingly, we set up a multiobjective optimization model with time window constraints to solve the scheduling optimization problem of offshore oil spill accidents with multiple locations and oil types. This model integrates the minimal sum of fixed costs, fuel consumption costs, maximum load violation costs, and time window penalty costs to solve the scheduling optimization problem of an offshore oil spill accident. An improved genetic algorithm is designed to solve the proposed mathematical model effectively and to make a scientific decontaminated decision-scheduling scheme. The practicality of the model and algorithm is validated by using a specific instance, demonstrating that the suggested method can effectively solve the schedule optimization problem for cleaning materials.
1 June 2021 in IOP Conference Series: Earth and Environmental Science
Marine oil spill monitoring technology has become a hot topic of marine environmental protection. This article introduced the principles and characteristics of marine oil spill monitoring sensors, analysised the implementation methods of marine oil spill monitoring. Through the comparison of the application situation, the problems in the oil spill monitoring are drawn, finally the development of the offshore oil spill monitoring research is prospected.