Leco’s 828 Series of Chemical Detection Instruments

The 828 Series, integrated with an on-board, touch-screen software platform and advanced hardware, enables users to effortlessly manage a broad range of sample applications.

The core performance and capabilities of the previous range of LECO macro combustion instruments have been preserved, while crucial enhancements have been made in reliability, uptimeand throughput.

All 828 Series models can be used with the S832 add-on, offering independent determination of sulfur. Macro sample mass capability combined with cycle times as rapid as 2.8 minutes render the 828 Series the perfect tool for different applications base, while providing unrivaled sample analysis throughput.

Features

Fast cycle time of 2.8 minutes for more productivity on FP/CN versions

Laboratory productivity can be maximized with an unparalleled sample throughput

Easy access to standard maintenance areas decreases downtime and the time needed for regular maintenance

Prolonged lifetimes of reagents improve the uptime of the instrument

Extended furnace reliability and efficiency with a regent-free design

Operator-centered, ergonomic design with a boom-mounted touch-screen interface

A robust 30-sample autoloader with an optional extended capacity for up to 120 samples increases the efficiency of laboratories

Applications

The 828 series is perfect for a wide range of applications, such as pet foods, feeds, fermentation products, milled products, grains and cereals, cheese products, dairy whey, plant tissue, fertilizers, sediments, soils, coke, coal, polymers and resins, waste materials, petroleum products, additivesand biomass materials.

Theory of Operation

The 828 Series can determine carbon/nitrogen, nitrogen/carbon/hydrogenand nitrogen/protein in a host of organic matrices, such as soils, food/feedsand fuels.

The instrument uses a combustion method with a vertical quartz furnace developed to manage a variety of sample matrices with prolonged reagent lifetimes and fast cycle times, providing unprecedented throughput combined with excellent instrument uptime.

To initiate an analysis, the specimen is weighed into a tin capsule or enclosed inside tin foil and positioned into the loader. Through a fully automated analysis sequence, the specimen is transferred to a sealed purge chamber in which atmospheric gas is eliminated.

The purged specimen is automatically transferred to a reticulated ceramic crucible inside the furnace. To ensure fast and complete sample combustion or oxidation, the environment of the furnace is made of pure oxygen with a secondary oxygen flow being guided to the specimen inside a reticulated crucible through a quartz lance.

In the CN828 and FP versions, the combustion gases are removed from the furnace via a thermoelectric cooler to eliminate moisture and are obtained in a ballast volume. In the CHN828 version, combustion gases are removed from the furnace via an afterburner that contains a reagent to clean sulfur compounds from the gas stream before they collect in the ballast volume.

Inside the ballast, the gases equilibrate and combine before a representative gaseous aliquot is removed and introduced into a flowing stream of inert gas for examination.

Based on the model of the analyzer, the aliquot gas is transferred to a thermal conductivity cell (TC) to identify nitrogen (N₂) and a non-dispersive infrared (NDIR) cell to detect carbon (as carbon dioxide).

In the CHN828 version, the ballast gas is also sent to an H₂O NDIR cell to determine hydrogen. TC cells are chemically non-specific unlike the NDIR cells, and hence a range of scrubbers and reagents are employed to guarantee quantitative detection of N₂ without any interference of chemicals.

Using a heated reduction tube, filled with copper, nitrogen oxide species (NOx) are converted to N₂ and surplus oxygen is removed. Water vapor (H₂O) is eliminated by Anhydrone and carbon dioxide (CO₂) is eliminated by LECOSORB.

Meticulous sequencing of the analysis offers the highest sample throughput by interleaving the sequence of sample loading with quantitation of the aliquot gases from the earlier specimen.

The 828 Series analyzer has several diagnostic sensing capabilities. Numerous pressure transducers (PT) have been included to offer the potential to leak check separate sections of the flow path.

Models

CHN828 Carbon/Hydrogen/Nitrogen

FP828P Nitrogen/Protein Performance Package

FP828 Nitrogen/Protein

CN828 Carbon/Nitrogen

Options

S832 Add-on offers independent sulfur determination of macro samples

Performance package

Boom-mounted touch-screen monitor

Cornerstone^® Mobile

SmartLine^® Remote Diagnostics