Standards Development

Scope

This International Standard describes the two procedures and the precautions to be taken in drawing representative samples of propylene and butadiene, in the liquid phase, for the purpose of their analysis.

It also sets out, in annex A, a diagrammatic representation of a system for the disposal of the portion of the sample not used in the analysis, and, in annex B, C and D, the sequence of operations for filling a sample cylinder in non-closed and closed sampling apparatus.

Purpose

Propylene and butadiene are both important basic raw materials of petrochemical industry, and extensively used in the manufacture of synthetic resins, rubbers, fibers and fine chemicals. In recent years, the world olefin industry has developed rapidly. According to IHS Market's handbook of Propylene 2019 and Butadiene 2020, the global production capacity for propylene and butadiene in 2019 were reported to be around 130 and 16.7 million tons, respectively.

International standards for propylene and butadiene are playing important roles in ensuring product quality and facilitating the global trade. Sampling technique, as an essential prerequisite for accurate analysis, largely influences the quality control of propylene and butadiene. While recently, the vast and growing market for propylene and butadiene is facing with increasing challenges as the demand for environmental protection and for the requirements of Health, Safety and Environment (HSE) aspects.

However, the ISO standards for ethylene sampling: ISO 8563, has never been revised since published in 1987. Some technologies used in ISO 8563 have difficulty in meeting the current technical and HSE requirements.

There are 3 major problems of ISO 85631987 that require revision. First, current ISO 8563 only have non-closed sampling which would cause emission of olefin chemicals during sampling which may do harm to environment and operator's health. As the requirements level of HSE has increased, “closed sampling” has become more popular around the world nowadays and has been adopted by many countries.

Second, there’s no purging procedures for sampling cylinder and purging procedures for connecting pipes are improper. This can lead to accumulation of heavy components at the bottom of sampling cylinder, and cause inaccuracy of the results. Third, no passivation treatment for containers and pipes is provided and this would affect the determination of trace polar compounds, such as methanol and sulfide in propylene and butadiene. Moreover, current sampling standard is still referenced by ISO 8174; 1986 for sampling to determine the content of polar compounds.

Therefore in our proposal we would like to address the above problems. “Closed sampling” is recommended as an alternative to better satisfy HSE requirements. The purging procedure is also revised to avoid the accumulation to guarantee the accuracy of analytical results. And sample containers passivated with non-reactive and non-absorptive materials are added.

By revising the international standard, on the one hand, ISO 8563 can keep up to date with technological trends, largely improve the reliability of the samples and accuracy of the analytical results, and better serve quality control of propylene and butadiene product. On the other hand, it can normalize sampling technique for industrial use, meet current environmental protection and HSE requirements and facilitate international trade