Free Silica Pretreatment Instrument

I. Product Overview

The HD-Si12 fully automatic free-silica pre-treatment workstation automatically performs the pre-treatment steps specified in the national occupational-health standard GBZ/T 192.4-2007 (Determination of dust in workplace air – Part 4: Free silica content): automatic addition of pyrophosphoric acid, automatic heating and stirring, automatic temperature rise, accurate temperature control at 245 °C – 250 °C for a 15-minute digestion, automatic cooling, automatic water addition, automatic re-warming, automatic filtration and automatic cleaning. The whole process requires no operator attendance, realizing full automation of free-silica separation pre-treatment.

II. Key Features

All-in-one automatic machine that completes pyrophosphoric-acid addition, digestion, cooling, filtration and cleaning, meeting the standard and ensuring data accuracy.

Water-rewarming function after adding water; liquid can be mixed in real time during filtration with adjustable mixing speed.

Equipped with ≥12 sample positions and ≥12 filtration positions; special glass sample cups ensure fast, uniform heating and special filtration devices resist acid/alkali and high temperature for rapid filtration; samples can be loaded continuously without stopping.

No sample transfer during operation, reducing loss between different vessels.

Automatically adds pyrophosphoric acid to samples, no manual addition.

Automatic cooling: after digestion the sample rack leaves the heating position for rapid cooling.

Automatic constant-temperature heating: liquid reaches 245 °C within 10 min and is held at 245 °C – 250 °C for 15 min.

Dual temperature sensors monitor liquid temperature in real time with control accuracy of ±0.1 °C.

Integrated constant-temperature heating module keeps all heating positions uniformly heated.

Acid/alkali-resistant high-precision metering pump with dosing accuracy <1%.

Special stirring rod integrates stirring and temperature measurement with adjustable speed for uniform samples.

Online pyrophosphoric-acid preparation: automatically adds phosphoric acid and prepares pyrophosphoric acid online.

Negative-pressure filtration system allows two samples to be filtered simultaneously with adjustable drip speed and vacuum, safe and fast.

Built-in debugging software automatically calibrates dosing accuracy.

Spray-nozzle cleaning of sample cups ensures complete, residue-free cleaning.

Exhaust device can connect to an exhaust duct or be placed inside a fume hood.

Reagent consumption monitoring with humanized low-level alert to ensure valid experiments.

Built-in touchscreen PC with software auto-control; information is entered directly without manual intervention.

Full-process visualization; software clearly shows current status and progress; temperature and digestion/stirring time are displayed and automatically recorded.

Safety protection: over-temperature protection for digestion heating and leakage/over-current protection for the whole unit.

Automatically records process parameters of each step, supports printing/export, storage ≥10000 groups.

Supports U-disk upgrade; optional remote upgrade for simplified firmware maintenance.

III. Technical Parameters