Synthetic detergent production scheme. capacity 30 thousand tons/t

1. Description of the technological scheme The technology of production of granular powder CMC tower method - spray drying of the composition - allows to obtain the finished product with high quality characteristics and good consumer properties. Powders have good looseness, do not dust, quickly dissolve in water by washing, have a uniform composition and uniform distribution of all components in granules of the finished product. The production of powdered CMCs using this technology is the most common in the world and in our country. Let's consider the main process diagrams of production of powder-like CMCs by spray drying, which differ from each other in the design, volume and layout of reactors - mixers, the principle of operation and the device of feedstock dispensers and automatic control systems for the dosing process, productivity of the finished product and other features. Existing plants for the production of powdered CMC with a design capacity of 30 thousand tons/year are equipped with a continuous or periodic composition preparation scheme. Production of detergent powders by spray drying of composition includes the following stages: reception, storage and preparation of loose and liquid raw materials, preparation and drying of composition, packing and packaging of finished product. The composition preparation unit is equipped with feed hoppers 41 for receiving sodium tripolyphosphate, sodium sulfate and soda from silos 1. In total, five bunkers were installed, three of which with a volume of 14.5 m3, and two - 11 m3. The bulk feed from the hoppers is fed by an auger or scraper conveyor to the dispensers 38, weighed alternately and discharged by the conveyor 37 to one of the two mixing reactors 35 of 8 m3 each. [10] Six tanks 42 are installed in the workshop for receiving liquid raw materials, four of which with a volume of 15 m3 and two - 12.5 m3 each. The tanks are equipped with heating jackets and frame stirrers. The liquid components are alternately charged to the VZHA-2 scale 43, weighed and discharged to the mixing reactor 35. The latter is equipped with a heating jacket and a blade stirrer. Upon completion of the preparation, the composition from the mixing reactor is pumped by pumps 33 through the settling filter 34 to the flow reactors 31 located at the same elevation. The composition from the flow reactors is supplied by gravity to homogenizers 32, of which by low pressure pumps 30 through fine filters 7 is supplied to high pressure pumps 6 and further to spray nozzles of the drying tower 8. Drying of the spray composition is carried out in the tower 8 by the flow of heat carrier, which is forced into the dryer header by the hot gas fan from the gas generator 28. The dryer operates in countercurrent mode . The spent heat carrier, which is a mixture of air with water vapor and CMC dust, leaves the top of the dryer and is supplied for dry cleaning to cyclones 9. Here, coarse powder particles are separated, which are fed through lock gates to the finished product conveyor 26. Dust-laden coolant from cyclones is fed by fan 10 to wet cleaning stage into scrubbers 11, where dust particles are collected almost completely, after scrubbers spent coolant is released into atmosphere . Powder from the bottom of the dryer is fed by conveyors 26 and 27 and bucket elevator 23 through vibrator 12 to a receiving hopper 21, from which non-ionic surfactants (depending on the formulation of the resulting CMC) are sprayed by dispensers 22 to mixer 18, where sodium perborate is added by dispenser 19. The finished product from the mixer is supplied to the receiving hopper 17, and then the bucket elevator 16 and the conveyor 14 are distributed to the hoppers of the finished product 15, from where it is supplied to the packaging. The powder packs are packaged in cardboard boxes, wrapping paper or heat shrinkable polyethylene film. Powders are packed in paper bags weighing up to 25 kg for supply by mechanized laundry