Principles of gas sampling: TOS with critical challenges

Sampling and analysis of materials in the gas phase is not covered in general sampling standards and guides, due to the complex nature of the subject matter. Most gas-phase materials exist in the region from ambient temperatures (~300 K) to combustion temperatures typically around ~1200 K. Common to both temperature range margins, though predominantly for hot gases, is the fact that continuous reactions often take place in material that is moving at high speeds, presenting less than trivial challenges to conventional Theory of Sampling (TOS). The purposes of representative gas sampling are many, but three standard cases are presented, covering the most dominating scenarios met with in science, technology and industry.

TOS reflections: is there a third way? (to promote the Theory of Sampling)

A standing discussion topic within the sampling community is: “What is the best way to promote the TOS—not only as a theory, but also as a tool to help customers?” The latter objective casts the question into a rather more direct format: “How to sell TOS-compliant equipment, sampling system solutions, consulting and audit services to customers with only little or no familiarity with the need for proper sampling?” These reflections address the two most dominant answers: i) the economic argument “You’ll lose a lot of money if you don’t…”; or ii) the technical argument: “You need to understand these critical aspects of the TOS, or else…”. However, this is usually but a futile debate; obviously one should be able to wield a flexible tactics which best matches a specific marketing or application need with one, or both, of these approaches. But a recent event has tickled the imagination—is there possibly also a third way?

10th World Conference on Sampling and Blending (WCSB10)

The WCSB10 conference will cover the latest research and application of the Theory of Sampling (TOS) and Blending in many important technology and industry sectors: mining, exploration, minerals processing, metals refinement, cement, food & feed, agri & aqua culture, pharmaceutical production etc. WCSB10 specifically has a broader societal, industrial and environmental emphasis with a special focus on sustainable science, technology and industry. This article provides an update on WCSB10 with information on all aspects of the conference.

Theory of Sampling and Sampling Practice, Third Edition

The second of three new textbooks in the field of Theory and Practice of Sampling.

Independent particle and lot selection of increment samples in the theory of sampling

Introduction. The theory of sampling developed by Pierre Gy does not prove the compatibility and consistency of discrete and continuous selection models. Discrete (independent particle) and continuous (lot) selection models are determined by incompatible properties of increment samples, which prevented from creating the consistent theory of sampling. Research methodology. The inconsistencies are removed at assuming the idea that there are differences in both separate ore lumps or mineral-dressing products and any locally selected parts of the rock mass under test called increment samples simultaneously available in any rock mass under test. The said differences are described by independent particle dispersion and increment samples dispersion. Composite sample permissible error formed in both discrete and continuous selection is attained by selection of the number of particles collected into the increment sample or their parts and the number of increment samples. Particle dispersion, increment sample dispersion, the number of particles in an increment sample and the number of increment samples combined in one formula make up the complete formula of the fundamental sampling error. The development of the theory of sampling. Based on the complete formula, the possibility of obtaining minimum masses of various sizes has been shown. Thus, for one and the same preset permissible error and from one and the same massif under test, it is possible to collect minimum mass of 17.55 kg (individual particle selection), minimum mass of 170.3 kg (collecting with the bucket sampler), and minimum mass of 10 g under the individual particle selection of particle parts (which is fulfilled under X-ray fluorescent on-stream analysis of material). Discrete selection of increment samples without particles destruction is an especial case of continuous selection method when it is possible to accept the condition that increment samples dispersion is equal to zero. It is possible under ideal mixing of the massif under test. Discussion. Minimum mass of a sample is not a constant. It is a function of increment sample mass. Minimum mass in individual particle selection can be accepted as a reference value of the minimum mass. In lot selection it can be significantly higher than the reference one, while in case of reducing particle size it can be significantly lower than the reference one.