A Study on a Risk-Based Design and Reliability Evaluation Framework for an Onboard Vacuum Drying System for EGCS Sludge Treatment = 선박용 EGCS 슬러지 처리를 위한 진공 건조 시스템의 위험도 기반 설계 및 신뢰성 평가 프레임워크 연구

다국어 초록 (Multilingual Abstract)

This study proposes a risk-based design and validation framework for an onboard vacuum drying system aimed at reducing the volume of sludge generated from wet exhaust gas cleaning systems. Unlike conventional thermal drying or land-based sludge treatment methods, the proposed system operates under a closed-loop vacuum environment, enabling moisture removal at low temperatures while effectively preventing secondary air pollution.
In this study, a systems engineering-based approach integrating functional analysis, hazard identification, structural stability assessment, and failure modes, effects, and criticality analysis was employed to ensure both operational safety and structural integrity. The dynamic behavior of the system was modeled using a first-order lumped parameter approach, and a hardware-in-the-loop validation platform was developed to verify real-time control algorithms.
Experimental results show that the system achieved a minimum vacuum pressure of approximately 10.7 Pa and maintained stable vacuum conditions at 3 Torr for more than 30 minutes. In addition, the system demonstrated high moisture removal efficiency, effectively reducing sludge mass and improving overall handling efficiency.
Furthermore, reliability validation based on failure modes, effects, and criticality analysis indicates that the risk priority numbers of major components were reduced by approximately 50–67% after design improvements, with an average reduction of about 53.3%. Significant improvements were observed particularly in vacuum sealing performance, temperature control stability, and sensor reliability.
In conclusion, this study presents one of the first integrated frameworks combining risk-based design and validation of a vacuum drying system for onboard exhaust gas cleaning system sludge treatment. The proposed framework provides a practical and scalable engineering solution for compliance with IMO environmental regulations and contributes to the advancement of environmentally sustainable ship operation technologies.

목차 (Table of Contents)

• 1. Introduction 1
• 2. System Overview and Technical Background 11
• 3. Evaluation process of Reliability based on Risk 18
• 4. Function and failure mode analysis of system 23
• 4.1. Functional analysis results 24
• 4.2. Conceptual Design 33
• 4.3. Hazardous Identification 38
• 4.4. Basic design evaluation through shape design and structural stability assessment 59
• 5. System Integration 94
• 5.1. System Architecture and Block Integration 96
• 5.2. Control Circuit Design and Signal Consistency 97
• 5.3. Integration-Oriented Design Based on FMECA Results 100
• 5.3.1. Heating-integrated Vacuum Chamber 100
• 5.3.2. Vacuum Generation System (Oil-type Vacuum Pump) 102
• 5.3.3. Moisture Protection System (Cold Trap) 103
• 5.3.4. Structural Integration (Base Plate Design) 105
• 5.4. Integrated Components and Prototype Implementation 107
• 5.4.1. Heating-Integrated Vacuum Chamber (Canister + Heater System) 109
• 5.4.2. Vacuum Generation Unit (Oil-type Vacuum Pump) 109
• 5.4.3. Moisture Protection Unit (Cold Trap) 110
• 5.4.4. Structural Integration Platform (Base Plate) 111
• 5.5. Measurement and Control Components 112
• 5.5.1. VDS Requirement Analysis and H/W-S/W Specification Review 113
• 5.5.2. Vacuum Drying Control Algorithm Development 120
• 5.5.3. Development of a Vacuum Drying System Simulator and Monitoring Testbed 125
• 6. Test and Validation 143
• 6.1. Validation Strategy and Framework 144
• 6.2. HIL-based Control Algorithm Validation 145
• 6.3. Functional Test of Integrated System 146
• 6.4. Performance Test (Drying Efficiency Evaluation) 148
• 6.4.1. Test Items 149
• 6.4.2. Test Specimens 149
• 6.4.3. Measurement Equipment 150
• 6.4.4. Test Procedures 151
• 6.4.5. Test Results 157
• 6.5. Reliability Validation Based on FMECA 165
• 6.6. Safety Verification 169
• 7. Conclusions 172
• Reference 178
• Abstract 185