Tank Cleaning Practice - A Handbook to: Planning, Recipe Formation, Best Practices and Techniques

Written by the authors of the renowned Dr. Verwey's Tank Cleaning Guide, this publication draws on decades of industry experience and builds on one of the most trusted references in the maritime sector. It translates proven expertise into a modern, hands-on guide focused on real-world tanker operations.

The guide supports crews and operators in optimising tank cleaning performance, covering best cleaning practices, operational risks and mitigation measures, safe use of equipment and compliance with international regulations, including MARPOL and other IMO requirements. The clear explanations help reduce turnaround times, prevent cargo contamination and ensure the highest standards of safety and environmental protection.

Tank Cleaning Practice is an essential resource for seafarers, tanker operators, shipowners, trainers, students, port agents and regulatory authorities alike. It is a practical reference for daily operations, training and decision-making - created by one of the most respected names in cargo tank cleaning.

Chemical, product and oil tankers play a vital role in global trade, as many chemicals and oils are produced in one part of the world and consumed in another. They provide safe and efficient sea transportation of chemicals and oils from production facilities to manufacturers, distributors and consumers around the world.

These tankers typically have tanks that can carry a wide variety of chemical and oil cargoes in order to maximise flexibility, cost-effectiveness and ship utilisation. The wide variety of cargoes and the need to utilise the tanks effectively often requires loading a cargo that is different to the one previously in the tank.

Therefore, cargo tank cleaning is an essential process in the operation of tankers. There are several hazards associated with cargo tank cleaning on tankships, and proper cleaning procedures and well-trained seafarers are essential to ensure the safety of crewmembers and prevent environmental damage. This Guide provides guidance on best practices, safety instructions and risk mitigation measures to prevent accidents and ensure compliance.

There are numerous regulations and guidelines related to cargo tank cleaning on tankers, including international standards such as the International Maritime Organization's (IMO) International Convention for the Prevention of Pollution from Ships (MARPOL). This Guide provides detailed information on regulatory requirements and helps ship crew to comply with applicable rules and regulations.

Proper cargo tank cleaning procedures can help maximise tanker efficiency by reducing turnaround time between voyages, minimising delays due to cargo contamination and ensuring cargo quality. This Guide provides guidance on effective cleaning methods, equipment utilisation, and best practices to optimise cleaning efficiency.

Tanker operators and crewmembers may have varying levels of experience and knowledge when it comes to cargo tank cleaning. This Guide serves as a knowledge-sharing tool, providing valuable information and insights to help improve crew training and operational performance.

In summary, this publication on cargo tank cleaning for tankers provides valuable guidance on safety, compliance, efficiency and knowledge sharing, making it a useful resource for students, crewmembers, ship operators, ship owners, port agents, regulatory authorities and other stakeholders in the maritime industry.

Introduction
1 - Physical Properties
1.1 Water Solubility
1.2 Melting Point
1.3 Viscosity
1.4 Boiling Point
1.5 Vapour Pressure
1.6 Flash Point
1.7 Density
1.8 Colour
1.9 Smell
2 - Chemical Properties
2.1 Polymerisation
2.2 Reaction with Water
2.3 Reaction with Water Hardness Compounds
2.4 Reaction with Oxygen
2.5 Putrefaction
2.6 Evaporation of Volatile Substances
2.7 Saponification
3 - Understanding Tank Cleaning Requirements of Differing Tanker Types and Trades
3.1 Tanker Types
3.2 Tank Coatings
4 - Cleanliness Requirement of the Next Cargo
4.1 Factors Affecting the Cleanliness Requirement of a Cargo
4.2 Visually Clean Standard
4.3 Water White Standard
4.4 High Purity Standard
4.5 Ultra High Purity Standard
5 - Environmental Factors when Tank Cleaning
5.1 Adjacent Tanks
5.2 Temperature
6 - Tank Equipment
6.1 Cleaning Machines
6.2 Deepwell Pumps
6.3 Heating Systems
6.4 Monitoring Systems
7 - Cargo Lines, Valves and Related Equipment
7.1 The Tank System
7.2 Example of a Cleaning Checklist
8 - Tank Cleaning Plan
8.1 Tank Cleaning Plan Overview
8.2 Tank Cleaning Atmospheres
9 - Tank Cleaning Recipe
9.1 Recipe Components
9.2 Recipe Structure
9.3 Cleaning Agents
10 de Safety
10.1 Risk Management
10.2 Flammability
10.3 Electrostatic Electricity
10.4 Toxicity
10.5 Corrosiveness
10.6 Personal Protective Equipment (PPE)
10.7 Asphyxiation
11 - Precleaning Meeting
11.1 Prerequisites: creating the tank cleaning plan
11.2 Conducting the Precleaning Meeting
12 - Cleaning Methods
12.1 Direct Cleaning
12.2 Injection Cleaning
12.3 Recirculation Cleaning
12.4 Recirculation via a Service Tank
12.5 Recirculation with Decanting
12.6 Steaming
12.7 Rinsing
12.8 Vent Mop Dry
13 - Checking of Results and Wall Wash Test Methods
13.1 Tank Inspection
13.2 Wall Wash Test Overview
13.3 Appearance
13.4 Colour
13.5 PTT Test
13.6 Water Miscibility Test
13.7 Chloride Test
13.8 Acid Wash Test
13.9 Non-volatile Matter (NVM) Test
13.10 Gas Chromatography
14 - Washing Water Analysis
14.1 Methodology
14.2 UV Spectrophotometer
14.3 Suitability
14.4 Advantages and Disadvantages
15 - International Maritime Regulations and Standards
15.1 IMO
15.2 MARPOL
15.3 SOLAS
16 - MARPOL Annex I
16.1 Key Elements of MARPOL Annex I
16.2 Oil Discharge Criteria
16.3 List of Oils
16.4 ODME
16.5 Special Areas
17 - MARPOL Annex II
17.1 Preparation
17.2 Pollution Category X
17.3 Pollution Category Y
17.4 Prewash Procedures with Recycling of Washing Medium
17.5 Pollution Category Z
17.6 Pollution Category OS
17.7 Persistent Floaters
17.8 Minimum Prewash Quantity
18 - IBC Code
18.1 Definitions
18.2 Application of the Code
18.3 Chapter 17 Cargoes (IBC Code)
18.4 MEPC.2

ChemServe

ChemServe is a service company specialising in publications and software for the marine industry.

ChemServe is the company behind Dr Verwey's Tank Cleaning Guide, the standard reference book for tank cleaning, the internationally renowned tank cleaning software ChemServe Miracle and the professional fleet management system ChemServe 3D.

ChemServe's specialised team combines more than twenty years of experience in the shipping industry with innovative technical solutions for its customers.

The company is based in the area around Hamburg, Germany.

Witherbys

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Witherbys staff have significant expertise in the fields of navigation and hazardous cargoes as well as in the presentation of complex subjects in a graphic and easy to understand manner.