1) The batching area section is dissolved according to the process requirements (toluene isopropanol = 85 15-80 20).
2) According to the process requirements, the reactor section adds the calculated water to the alkali kettle (the amount of water added to the alkali gold = the total water volume of the system is 460 kg and the water content in the solvent) (the water content in the solvent = the total amount of solvent 7300 kg * the proportion of water in the solvent), and 790 kg of flake alkali (solid) is put into the alkali gold after adding water;Raise the temperature in the alkali kettle to more than 80 degrees Celsius for more than 40 minutes to completely dissolve the solid alkali.
6500 kg of solvent was injected into the reactor and stirring (frequency of 45 Hz) was turned on to vacuum the pressure in the 3 reactors to -006mpa( -0.6 kg), the chemical alkali is pressed into the reaction kettle, and 200 kg of solvent is injected into the alkali kettle after the alkali in the alkali kettle is hydraulically purified to spray the alkali pressure pipeline.
4) After the reaction is cooled to 23 degrees, open the manhole cover within the specified time (7 minutes to feed (800 kg of refined cotton), and spray 600 kg of solvent into the kettle at the end of feeding, and then start the alkalization reaction (alkali reacts with refined cotton to generate alkali cellulose). After feeding, tighten the manhole cover to replace the gas in the kettle: continuous vacuuming and nitrogen filling 4 times (vacuuming to -0.).06mpa, 7 min;Charge to 0 3 times before filling nitrogen06 MPa, the last rush to 008 mpa)。The alkalization timer starts for 2 hours after spraying, and the temperature is controlled at 2023 degrees.
5) About 7 minutes before the end of the alkalinization reaction, the pressure in the reaction gold is pumped to -006mpa (-0.6 kg), and after the alkalinization reaction is completed, the etherifying agent is added to the reaction kettle: propylene oxide is added 303kg, soil is 3kg, and chloromethane is added 950kg3kg (propylene oxide is added first and then chloromethane is added). After adding the etherifying agent, cold stir for 40 minutes to fully distribute the chemical agent. After the end of cold stirring, the etherification reaction (alkali cellulose reacts with etherifying agent) begins, and the etherification reaction consists of two stages: the first stage raises the temperature to 56 degrees Celsius 2 degrees Celsius for 2 hours and 30 minutes, and the second stage raises the temperature to 87 degrees Celsius 2 degrees Celsius constant temperature for 2 hours and 30 minutes. After the etherification reaction is completed, the reacted material is pressed into the desolubilization kettle: first add 40 cm of lower layer liquid to the desolubilization kettle, and then add a quantitative amount of 20 cm of acetic acidAfter adding acetic acid, start pressing the material. Starts 15 minutes after neutralization at the end of the compaction**. In the process, toluene isopropanol and water and some by-products will enter the equipment along the pipeline at high temperature, and high-temperature water (above 95 degrees) and lower liquid (80 cm to 120 cm) will be continuously added to make the solvent of the system sufficient. The solvent enters the stratifier, and the static precipitation is stratified (the upper liquid is toluene and isopropanol, and the lower liquid is mainly water and a small amount of isopropanol and toluene), the upper liquid is reused, and the lower liquid is injected into the distillation system for distillation, and the solvent obtained is recycled. The hot water added in the process can be washed at the same time to ensure the output, and the neutralization time is within 3 hours.
7) Centrifugal drying, crushing, screening, and mixing of good materials are driven into the buffer tank by the desolubilization kettle with a screw pump and then enter the centrifuge for centrifugation (separating the water from the material), and the water is discharged into the sewer after separation, and the material enters the fluidized bed for drying (the operator can control the centrifugal drying speed according to the moisture needs of the semi-finished product: the maximum centrifugal time to ensure the output is not more than 3 hours) The material enters the crusher for fine crushing, and the crushed material is screened by the vibrating screen to meet the specified requirements: after the screening, the material is sampled and tested by the laboratory according to the sales order requirements for batching, and the finished product section is mixed according to the batch issued by the laboratory, and the mixing strictly abides by the "mixing regulations", and the mixing is loaded into the finished product bag for packaging after sieve. (Finished product mixing regulations: the finished product process operator in five single batches according to the laboratory issued by the feed fan all hit to the homogenization bin after opening the homogenization bin automatic mixing (time 55 hours): after the automatic mixing is completed, the material will be from the homogenization bin to the packaging bin with a discharge fan;The packing starts 1 hour after the packing bin is fed, and the weight of each bag is 2510.5kg, packed and put into storage. Hydroxypropyl methylcellulose ether manufacturer