Окружающая среда
Application Database
Отчёты о применении (28)
Representative results require adequate sample preparation
The following situation is typical for many production plants: After a routine quality check, the production process is stopped or an already produced batch is suspended, because the analysis results were not within the relevant critical values. But does the tested product really deviate from the specifications? The quality control managers are convinced of this because modern analysis instruments provide results with very low tolerances. The sample in question was tested several times and the result was confirmed. The question is why the product does not match the specifications although the production parameters have not been changed in any way.
The possibility that the tested product is indeed deficient cannot be excluded. However, it is often not the product itself which causes irregular analysis results but a lack of understanding of the steps which come before the analysis.
Preparation of Elastic Plastics for the Detection of PAH
Polycyclic aromatic hydrocarbons, short PAH, are usually a by-product of combustion and can be found, for example, in cigarette smoke or oil-based products. Mineral oil containing PAH is often used in rubber products as plasticizer, especially in black-coloured products such as car tyres, rubber grips of tools or rubber shoe soles. It was discovered that some polycyclic aromatic hydrocarbons are carcinogenic, so that maximum permissible values have been determined for the concentration of PAH in consumer products.
Size reduction of elastic plastics with volatile components
Neutral-to-analysis sample preparation for the detection of PAH and phthalates
Air Jet Sieving of Bulk Materials
Particle size analysis and particle size distribution are important criteria for the quality control of bulk materials. In a running production process, the results of a quality check must be available quickly to allow for immediate adjustment of the production parameters. Depending on the expected particle size and sample volume, different sieving methods and sieving machines are suitable for analysis. The method used for particle size analysis is primarily determined by the fineness of the material to be sieved. For dry sieving of samples with particle sizes below 40 microns, air jet sieving is the method of choice.
Toxic analyses of biological samples
Cryogenic grinding facilitates the preparation of animal samples
Efficient Grinding at –196 °C
RETSCH’s New CryoMill for Safe and Reproducible Grinding with Liquid Nitrogen
Preparation of Soil, Sewage Sludge and Sediment Samples in a Wastewater Treatment Laboratory
The preparation of a mixture of organic and inorganic samples holds some difficulties: whereas sand, clay and stones can usually be ground to homogeneous samples with suitable laboratory mills, the high energy input can cause samples with organic components such as fat or starch to cake. Carsten Bunn, a laboratory technician at the waste water treatment laboratory BRW, has to deal with this problem every day. He treats samples which are taken from the sand traps of the wastewater treatment plants and consist of exactly that mixture. The sediments of household and industry waste water not only contain sand, clay or leaves but anything that people nowadays dispose of through the sewer system: cellulose, hair and especially food residues.
Fast and Reproducible Sample Preparation with a Vibratory Disc Mill
The Vibratory Disc Mill RS 200 from Retsch is used for the quick, loss-free grinding of hard, brittle and fibrous materials to analytical fineness.
Cement - representative sample preparation is important
To produce high-quality cement, the mineralogical and chemical composition of raw materials as well as intermediate and finished products has to be determined. At each stage of the production, samples have to be taken, processed and analysed to ensure quality control without gaps. Retsch offers a range of instruments that are used for sample preparation during the complete production process, from the quarrying of the raw materials to the final product. The typical sample preparation process involves preliminary size reduction, sample division and fine size reduction before the sample can be submitted to further analyses....
Green Chemistry in the Lab
Mechanochemistry is a very effective method to carry out syntheses without solvents and by-products. The technical literature describes a great number of reactions where a conversion of 100% is achieved. A precondition for the establishment of mechanochemistry in the industrial sector is the availability of suitable laboratory mills. A decisive factor is that – similar to conventional preparative chemistry – ambient parameters such as pressure and temperature can be documented and monitored. The Planetary Ball Mills and Mixer Mills from Retsch fulfill these requirements.
Tracking down hazardous substances (RoHS/WEEE)
Preparing electronic waste for obtaining representative analytical samples.
A solution for converting an electrical appliance into a meaningful analytical sample is described using a remote-controlled toy car as an example.
Size reduction within the context of sample preparation
In general “size reduction” is taken to mean the disintegration of solid substances by mechanical forces without altering their state.
Sample Preparation of Electronic Scrap in the Context of RoHS and WEEE
Since August 2004 new EU directives for the disposal of used electrical and electronic appliances as well as the restricted use of certain hazardous substances in these devices have become effective.
Sample Preparation of Plastics for X-Ray-Fluorescence Analysis
The elemental analysis of plastics has become more and more important. EC directive 91/338/EWG regulates the ban of cadmium in PVC, EC directive 94/62/EC defines limits for cadmium, lead, chromium and mercury in packing materials and EC directive 2000/53/EC defines limits for the same elements in end-of-life vehicles. This has created a strong need for a rapid and reliable testing method.
Cryogenic Preparation of Sample Materials
Within the context of sample preparation, size reduction plays an important role as it has a substantial influence on the results of the subsequent analysis. If the particles are too coarse or non-homogeneous the results of the analysis may turn out to be incorrect, especially if there is only a very small amount of sample material which represents the total amount.
Sample preparation of electronic scrap with SM 2000 and ZM 200
RETSCH mills in the context of RoHS and WEEE
Reliable sample preparation in food technology
An efficient sample preparation procedure for rapid, reliable and reproducible analytical results is becoming increasingly important today. Ever more stringent requirements are being set both in research and production, e.g. for product monitoring and quality control.
Analysis of cadmium in plastics
In recent years, mass media have focused on the topics of the environment and environmental conservation. With the advancement in scientific technology, resource development has progressed.
Sample Preparation of Solid Materials for the XRF-analysis
X-Ray fluorescence is one of the most versatile methods to determine elements in a sample. The material is exposed to x-rays that cause each element to emit its own unique fluorescent x-ray. The subsequent analysis of the results is based on comparisons to standard samples with given chemical composition.
The Representative Sample Preparation of Waste
Now that a certain environmental awareness has developed in the population over the past few years, our efforts are geared not only to avoiding waste, but also to reducing the mountains of waste which still arise by means of raw material recovery and the reintroduction of secondary raw materials into the industrial cycle.
Die neue Power Generation
Planeten-Kugelmühlen haben seit jeher einen festen Platz in der täglichen Laborpraxis zur Feinzerkleinerung unterschiedlichster Materialien. Neben dem Mischen und Zerkleinern hat sich in den letzten Jahren auch im mechanischen Legieren z.B. thermoelektrischer oder hochkoerzitiver Materialien ein weiteres Anwendungsgebiet ergeben.
Kraftvolle Schneidmühle
Die Schneidmühle SM 300 überzeugt vor allem bei schwierigen Zerkleinerungsaufgaben. Sie verfügt über eine variable Drehzahl von 700 bis 3000 min-1 und zeichnet sich durch hohe Durchzugskraft aus. Die Mühle lässt sich komfortabel bedienen sowie schnell reinigen. Die SM 300 garantiert eine zuverlässige und sehr effektive Probenvorbereitung im Labor.
Molienda ultrarrápida y ultrafina
El nuevo molino ultracentrífugo ZM 200 de RETSCH es un molino de rotor no sólo extremadamente rápido y cuidadoso con el material molido, sino también de uso universal gracias a su amplia gama de accesorios.
Probenvorbereitung von Böden
In Industrienationen mit hoher Besiedlungsdichte und einem begrenzten Angebot an Industrie- und Gewerbegebieten unterliegt die Nutzung von Gebäuden und Flächen einem dauerhaften Wandel. Daher sind Bodenuntersuchungen für Investoren, Behörden und Privatpersonen unumgänglich. Umweltanalytische Untersuchungen bilden die Basis, um Gefährdungen aufzuzeigen und damit Menschen und eingesetztes Kapital zu schützen. Bei SGS Institut Fresenius in Herten werden bis zu 400 Bodenproben am Tag aufgearbeitet und analysiert. Hierbei wird sehr genau darauf geachtet, dass geltende Normen und Verordnungen eingehalten werden. In Deutschland gilt die BbodSchV, wobei die Analytik auch auf die Vorschriften anderer Länder angepasst wird.
























