Coal sulfur analyzer

The instrument is designed according to the coulometric titration method in GB/T214-2007. The whole measuring process of the instrument is controlled by microprocessor intelligently. Many intelligent control functions are newly added, such as automatic control of electrolytic switch, PID mode control of furnace flow, etc. The microprocessor performs various corrections and processing on the test data, so that the measured data is stable and the parallel samples are good. The accuracy and precision of the results are better than the requirements of the national standard GB/T214-2007. It also has many advantages, such as large screen display of Chinese characters, friendly human-computer interface, simple and easy-to-learn keyboard operation, high degree of automatic intelligent control, and compact size. Therefore, it is an ideal sulfur measuring instrument for laboratories at present.

Features
Compared with similar sulfur analyzers, this instrument has the following features:
[1] Friendly human-machine interface, simple keyboard operation, easy to learn and use.
[2] The furnace temperature adopts PID mode to control the furnace flow, with high temperature control accuracy, which can effectively protect the silicon carbon tube and extend the service life.
[3] The furnace temperature and correction can be directly changed by keyboard input.
[4] Intelligent control of the on and off of the electrolysis switch will not cause over-electrolysis due to the order of switching on and off.
[5] When making coal samples, you can check the furnace temperature, furnace flow, indication voltage, process time and sulfur content at any time, and the test process is clear at a glance.
[6] Automatically determine the titration end point, shorten the experimental time and improve work efficiency.
[7] If the moisture value is entered, the dry agent sulfur and moisture value will be calculated and printed.
[8] This instrument can memorize the latest 100 historical records when the power is off, and can print the historical records at any time.

Main technical indicators
[1] Sulfur measurement range: 0-10%
[2] Sample combustion analysis time 3–9 minutes, intelligent judgment titration end point return.
[3] Temperature control: accuracy 1150±5℃. Temperature measurement: accuracy 0.5 level; heating body is silicon carbon tube, high temperature zone length ≥90 mm, temperature is 1150℃±5℃ (temperature can be adjusted as needed).
[4] Heating speed: 25–30℃/min, about 35 minutes to reach 1200℃.
[5] Electrolytic cell: volume 450 ml, metal platinum electrode.
[6] Instrument stability: enter stable state within 1 minute after power on.
[7] Power supply: 220V±20% 50Hz.

Analysis principle
The coal sample is burned in a purified air flow at a high temperature of 1150℃. All forms of sulfur in the coal are burned and decomposed, and carried to the electrolytic cell by the air flow to combine with water to form H2SO3. Since it destroys the original dynamic balance of iodine-iodide ion pairs in the electrolytic cell, the instrument immediately outputs current to electrolyze potassium iodide solution to generate iodine to restore the original dynamic balance, which is the coulometric titration in GB/T214-1996. The specific amount of current consumed to restore the original dynamic balance is directly related to the amount of sulfur burned and decomposed in the coal sample, which can be measured and calculated by the microprocessor, so we can derive the total sulfur content in the coal.