Sulphur analyzer and troubleshooting [1] Air tightness of the airway is reduced: Flowmeter indication should be between 0.8~~1.2. If air tightness is reduced, the following components should be inspected: air pump, flow meter, glass tube, rubber tube, and air connection. [2] electrolytic cell 1. Leakage in the electrolytic cell leads to a decrease in airtightness of the gas path. 2. Dirt on the four pole pieces in the electrolytic cell should be cleaned 3. The four pole pieces and the controller in the electrolytic cell should be connected reliably. 〠3 】 Stirrer: The disappearance of the magnetic force of the stir bar is a common cause of stirring out-of-step and should be replaced. 〠4 】 Temperature Control Section 1, A. The temperature shows 1999 °C, indicating that the thermocouple circuit is not open or its internal circuit is open. B. The temperature does not increase at all times, but there is a heating current, which means that the thermocouple is reversed. C. If the temperature shows room temperature, it means that the thermocouple wire is short-circuited. 2, the temperature value is less than the set furnace temperature, there should be heating furnace flow. If the furnace flow shows 0.0A, it means that the insurance tube is bad, and the internal opening of the silicon carbon tube itself or the connection is not connected. 3, temperature fluctuations are too large, generally the reason for the silicon carbon tube. The resistance value should be 7~~8 Ω. It is recommended to purchase original accessories of our company. [5] Sample delivery mechanism In order to match the fault diagnosis of the sample sending machine, four indicators are provided on the main board of the instrument. The fault location can be judged according to the condition of the indicator lamp when a specific fault occurs. ◎ ◎ ◎ ◎ 1 2 3 4 1 : This indicator should light when the motor advances. 2 : This indicator should light when the motor is back. 3: This indicator should light when the sample delivery mechanism stops at 500 °C or 1050 °C. 4: The indicator light should be on when the sample delivery mechanism is in its original position. Reagents and materials Tungsten trioxide (HG10-1129) Color Change Silicone: Industrial Products Potassium Iodide (GB/T1272) Potassium bromide (GB/T649) Glacial acetic acid (GB/T676) Distilled water ☆About electrolyte preparation: Weigh 5 g of potassium iodide, 5 g of potassium bromide, dissolve in 250 ml of distilled water, and add 10 ml of glacial acetic acid. The electrolyte can be reused, and the length of time used depends on the number of repeated uses and the sulfur content of the sample. The electrolyte can be used at pH 1-3, but when the pH is less than 1, the electrolyte should be re-formulated. ☆About the preparation of coal samples: Before the sample is weighed, the sample in the sample bottle should be mixed as evenly as possible. It is best to pinch the sample bottle with the lid on top, and the wrist should make a circular motion from top to bottom, and do not shake it up and down. Sample bottle. Or open the bottle cap and stir the sample with a weighing spoon. Full sample mixing is the key to ensure accurate and accurate results. ☆ Instrument maintenance: 1. After electrolysis occurs in the electrolysis cell, the electrolysis cell should be opened, and the electrode should be scrubbed with ethanol or acetone to make the electrode appear bright silver-white. Use the fine sandpaper or knife to deal with the contamination seriously, remove the attachments on the electrode, and then use Ethanol or acetone cleaning, be careful not to use other organic solvents to scrub the wall of the Plexiglas cell to prevent possible shell cracking. 2. The glass melting plate should be cleaned in time when there are black sinks on the pipe. The cleaning method is as follows: Remove the electrolytic cell (open the lid) and place some water in the electrolytic cell so as not to submerge it into the melting plate. Tilt the cell and inject the prepared wash solution (5 g of potassium dichromate and 10 ml of water, add 100 ml of concentrated sulfuric acid after cooling by heating) with a pipette to the branch of the melt plate. , In repeated 1 - 2 times, you can remove the black sink structure in the melting board and branch pipe. Then rinse the electrolytic cell with tap water, and use the ear syringe to pump water from the melting plate until no wash liquid remains. The melting plate should be white as it was. Absorb the glass melting plate and its branch tubes with filter paper, and then add the electrolyte. 3 The rubber pipes connected to the gas line should be inspected frequently, and the leaks at the joints are most likely to be aged. 4 The small porcelain boat with coal sample should be kept in a clean container. The new porcelain boat should be treated with high temperature before it is used for the first time. The weighed porcelain boats with coal samples must pay attention not to be contaminated by coal-filled hands or tables, and it is advisable to have a white porcelain boat that houses porcelain boats. 5 Periodically test the instrument with the standard to check whether the instrument is normal. If the reducer breaks, the electrolyte pole is contaminated, the gas path leaks, and gas is blocked. 6 The instrument should be protected against ingress of dust and corrosive gases and placed in a dry environment. If it is not used for a long time, it should be covered and the power should be taken out regularly to bake the moisture in the instrument. If the electrolysis cell is not used for a long time, the connecting hose should be removed to prevent its aging and adhesion. ☆ Failure phenomena and their causes and solutions: 1. Air purification device: includes a flow meter, two glass tubes, an air pump and connecting hoses. (1) Flowmeters: The inlet and outlet of the flowmeter may be blocked by the silica particles in the drying tube due to the connection to the drying tube, which may cause the gas flow to be unstable, or may not be adjusted to the required flow; if the interior enters the liquid or enters The combination of dust and moisture will cause a large resistance to the small float, which will also cause the flow to be unstable or unable to adjust; its own damage, such as the tight internal air circuit, the needle valve also causes the flow to be unadjustable or unstable. (2) Glass tubes: The lower ends should be filled with deesterified cotton. The two upper and lower air holes are shielded so that their contents do not inhale into the connecting pipe, blocking the air path. If it has small cracks, it can be sealed with special glue. Once the silicone is completely discolored, it must be replaced in time. (3) Air pump: The principle is that the interior is driven by electromagnetic action to move the two cups back and forth to produce aerodynamic force. Its failure is usually caused by the rupture of two cups. When the cup breaks, the pumping force drops, showing that the float of the flowmeter has been falling down, and the flow rate is unstable, which is the same as that of 1 and 2. (4) Rubber tube: It is prone to aging, causing system air leakage and unstable flow. The performance of the above failures are the same. The leak detection work for each test is for them (of course, also including the electrolytic cell) reflected in the sample results are to make the measurement results unstable, ups and downs. 2 electrolytic cell (1) The top cover of the electrolytic cell should be tightened, the seal ring should be aged, and the glue should be opened at each access hole, which is the cause of air leakage. (2) The four pole pieces in the electrolytic cell, two small groups, are two large groups of indicating electrodes, which are electrolytic electrodes. The indicator electrode serves to sense the titration of the electrolyte and to control the titration of the electrode. If any electrode goes wrong, it will cause the experiment to fail. Therefore, it must be ensured that the surface of the four pole pieces is clean, and no cracking may occur at the seal. If the electrode pad is instructed to be disconnected from its lead (such as when the sealer cracks), the electrolytic electrode will continue to be electrolyzed and cannot be stopped. The electrolyte is red, and the screen is counting rapidly (even if the coal sample is not put). The phenomenon of surface sticking is also such a phenomenon: if the electrode plate is disconnected from its lead, it will cause the electrolyte to become whiter when it is sampled, but the screen is not Counting, that is equivalent to the electrolytic switch off state. The surface fouling is manifested as delayed electrolysis, that is, the electrolysis suddenly turns on when the liquid is very white, and the measurement result is seriously low and unstable. Treatment method: The surface of the dirty, can be cleaned. If the split rubber is disconnected, the residual glue may be removed, the plastic pipe connected with the pole piece is removed, the inner wall thereof is cleaned, the eroded lead part is replaced, the re-soldered part is re-welded, and the sealant is not glued. The electrolyte may have accumulated inside, the leads have been corroded, and the pole pieces are not conducting. (3) Leads of electrolytic cell outlets and sockets on the machine are subject to long-term oxidation. The phenomenon of loosening caused by loosening is the same as if the pole piece is contaminated or open circuit. The plug can be plated with a thin layer of solder to remove the oxide layer and increase the plug. The tightness of the socket can also be directly welded to the corresponding point in the machine. 3 Stirrer: The principle is to use a rotating magnetic field to drive the magnetic stirring rod in the electrolytic cell to rotate. If the stirrer's magnetic field is weakened or its motor speed is slowed, the stirring speed is correspondingly slowed down. The disappearance of the magnetic force of the stir bar is a common cause of the stirring out-of-step phenomenon, which can be replaced or magnetized. The faster the stirring speed, the more favorable the uniform titration of SO2 hydrate. The reason why the stirring speed is too low and the measurement result is unsatisfactory is that if the stirrer is stopped in the experiment, electrolysis will occur. 4 burner section: (1) The correct installation of the thermocouple is very important. Insert it downwards and return to the silicon carbon tube. 2mm. The farther away, the instrument display value is lower than the actual furnace temperature delay rose less than the set temperature (actual furnace temperature has already reached) or rose to set the °C, the control accuracy is not good, in the temperature point up and down a few Ten or even fluctuations on Baidu: If the thermocouple touches on the silicon carbon tube, when it rises to a high temperature, there will be leakage current from the silicon carbon tube into the machine, causing the display temperature to fluctuate greatly, even falling under a straight line. The temperature (negative temperature separation from the temperature drop caused by the return of the thermocouple) severely damages the instrument temperature circuit. Abnormal temperature control, furnace temperature is too high (above 1050 °C) phenomenon is: Look into the furnace, is not a normal red light, but has been bleached, often resulting in adhesion of quartz boat and reducer, serious The reducer burns, and the reducer sticks to the silicon carbon tube. If the coal sample is fed, the coal ash will melt on the porcelain boat and it will not be scraped off. Adjust the thermocouple position or adjustment according to the actual situation. Set the temperature. If the thermocouple is not connected or is open internally, the instrument displays 1 to indicate over-range: if the thermocouple is shorted, the instrument always shows room temperature. (2) The reducer is a sealed combustion chamber of the sample, ensuring that the SO2 gas generated by combustion enters the electrolytic cell under the action of the air pump. If it cracks or breaks, it will cause the escape of sulphur-containing gas, making the measurement result seriously low and unstable. The different-diameter pipe is at a high temperature and hidden in the furnace body, so the fracture is hidden, and when it is abnormal, it can be released. Bolt fastening screws at the mouth and take it out for inspection. (3) 10 Ω is the best value for silicon carbon tube debugging. If the resistance is too large or too small, the maximum heating current will be reduced, and the natural resistance will increase. The performance is that the warm-up time becomes longer or rises to less than the set temperature: At this time, the furnace flow analog display light cannot reach the 9 or 10 light position. The treatment method is generally replaced by good, and the resistance value can be measured when it is determined. The maximum allowable difference of total sulfur determination (GB214-83) F Maximum allowable error The same laboratory Different laboratories 0.05 0.10 1-4 0.10 0.20 >4 0.20 0.30 For more information on coal detection, please visit Huayuan's website http://, http://, or call us Dry Red Wine,Pure Taste Red Wine,Famous Red Wine,Dry Red Table Wine Ningxia ZhaiXianSong Commercial and Trading Co.,Ltd. , https://www.nxupin.com
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