ASTM E2664-22

Overview

ASTM E2664-22: Standard Practice for Methanol Wall Wash of Marine Vessels Handling Polyester Grade Monoethylene Glycol outlines procedures to determine the cleanliness and suitability of marine cargo tanks prior to loading polyester grade monoethylene glycol (MEG). This practice is essential due to the extremely high purity requirements for polyester grade MEG, which can be compromised by traces of contaminants such as oxygen, hydrocarbons, water, and chlorides. The methanol wall wash method helps operators assess tank conditions and mitigate the risk of contaminating sensitive cargoes through thorough inspection and representative sampling.

Key Topics

• Purpose of Methanol Wall Wash This standard details a process to ensure cargo tanks are free from harmful contaminants before loading high-purity polyester grade MEG. The test checks for residual impurities by sampling tank walls using methanol.

• Process Steps

  • Use reagent-grade, low-chloride methanol for wall washing and sampling.
  • Employ clean personal protective equipment (PPE) and ensure all sampling equipment is free of contaminants.
  • Select and sample multiple locations on each tank bulkhead, focusing on areas likely to retain residue or show signs of previous contamination.
  • Include non-typical areas, such as discolored or damaged sections, in the sampling process.

• Analytical Parameters The method includes laboratory analysis of samples for:

  • Appearance (clarity and absence of particulate matter)
  • Color (measured on the platinum-cobalt scale)
  • Hydrocarbons (presence/absence test)
  • Chloride content (measured using ion chromatography)

• Significance for MEG Quality Polyester grade monoethylene glycol can be damaged by even minimal contamination, resulting in product degradation, especially from aromatic hydrocarbons which affect UV transmittance.

• Quality Control and Safety

  • Reagent grade chemicals and high-purity water are required.
  • Safe handling of methanol and adherence to regulatory and environmental standards is emphasized.
  • Laboratories should maintain appropriate quality control charts and follow industry-recommended precision and reproducibility practices.

Applications

• Marine Vessel Operations The methanol wall wash procedure is widely used before loading cargo tanks with polyester grade MEG in marine vessels. It provides assurance to producers and receivers that tanks meet required cleanliness standards, reducing risks of cargo rejection and subsequent financial or reputational impacts.

• Quality Assurance for Chemical Transport By implementing the wall wash test, operators comply with quality specifications and contractual agreements for shipping high-purity chemicals. This is particularly critical in petrochemical and polyester industries, where purity directly influences process yields and finished product performance.

• Regulatory Compliance Companies using this procedure demonstrate adherence to internationally recognized methods, ensuring their operations meet the principles established by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

Related Standards

This standard references and complements several other ASTM standards, providing a comprehensive framework for sampling and analysis of chemical cargoes:

• ASTM D1193: Specification for Reagent Water
• ASTM D1209: Test Method for Color of Clear Liquids (Platinum-Cobalt Scale)
• ASTM D1722: Test Method for Water Miscibility of Water-Soluble Solvents
• ASTM D4176: Test Method for Free Water and Particulate Contamination in Distillate Fuels
• ASTM D5386: Test Method for Color of Liquids Using Tristimulus Colorimetry
• ASTM E2469: Test Method for Chloride in Glycols by Ion Chromatography
• ASTM E2680: Test Method for Appearance of Clear, Transparent Liquids
• ASTM E1547: Terminology Relating to Industrial and Specialty Chemicals

By following the procedures in ASTM E2664-22, organizations reinforce best practices in marine chemical transport, ensuring the quality and integrity of polyester grade monoethylene glycol shipments.