When solid waste is generated, the potential for disposal can be considered. It is possible to recycle, for example, salts (NaCl, CaCl2, HCl and gypsum). These products can be obtained by evaporation or recrystallization of salt from flue gas treatment system wastewater, either on site or in a centralized evaporation plant.
When scrubber effluents are treated separately and evaporated, recyclable products such as salts or hydrochloric acid can be obtained.
The recycling potential of such products is highly dependent on the quality of the product. In salt recovery, scrubber effluents are treated with sodium hydroxide and calcium carbonate to produce solid gypsum, which is separated to leave a liquid containing primarily sodium and calcium chloride. The recycled product is subject to quality control or even further processed to improve quality and then sold.
Achieved positive effect. The main purpose of the operation is to prevent the discharge of salty wastewater into the sewer system. This is achieved by evaporating the scrubber effluent from the flue gas cleaning system. If solid sodium chloride is to be separated individually from said solution, this is achieved by evaporating the solution until the salt content is greater than 30%, at which level the pure salt crystallizes.
These recyclable salt products are the most commonly reused in regions for winter de-icing. Reusing recycled salts can save natural resources.
Environmental impact. The main disadvantage of external wastewater evaporation for salts is not only operational and material problems, but also the high energy consumption required for evaporation.
Operational features. The evaporation of wastewater containing salts depends on the salt concentrations, which can vary greatly. In addition to corrosion problems, relatively high investment and operating costs must be taken into account.
There are several operational challenges to producing gypsum alone. However, the quality of gypsum is determined not only by its purity with respect to the presence of other undesirable components, but also by its color. Typically you can expect to produce approximately 2-5 kg of recyclable products per tonne of waste.
In the production of calcium chloride, emphasis must be placed on the possibility of excessive corrosion that may occur and unintended phase changes from solid to liquid and vice versa.
Often, novice entrepreneurs, thinking about what kind of business to open, do not pay any attention to seemingly completely obvious industries, in particular, mineral processing, etc.
At the same time, many are victims of the stereotype that the development and processing of mineral resources is the prerogative of state enterprises or large corporations. But this is far from true. Although large organizations, and especially the state, of course have more financial, administrative and other opportunities to develop deposits, some minerals, and in particular table salt, can be extracted by small enterprises.
And even if it is not possible to engage in salt extraction, then processing and subsequent sales are quite within the capabilities of a novice businessman.
The only limitation to the table salt production business is geographical. As you know, most of the salt deposits in Russia are located in the Volga region, accordingly, the enterprise should be opened there - this will help avoid unnecessary transportation costs: salt, as you know, is the cheapest (after water) food additive, so any overexpenditure included in it the cost may at some point make it unprofitable.
In fact, the salt market is extremely sensitive to any price fluctuations, for example, for gasoline or electricity: by and large, the price of salt is the sum of the costs of its extraction and packaging, and the cost of raw materials can be considered zero (there are no material costs as such, there are only the cost of mining halite - a mineral of rock salt).
In addition to the development of halite deposits, it is sometimes practiced alternative way production of table salt - evaporation from salt water, for example, sea water, or water from saline or intentionally dried reservoirs - ponds and lakes. However, it becomes profitable only with large production volumes and the presence of a sufficient number of the above reservoirs.
However, despite the apparent difficulty in tracking and regulating cost, it exists mostly in descriptions - a well-thought-out and skillfully managed salt production business does not require virtually any intervention: salt is not just popular or liquid, but an almost ideal product with a stable high demand and an almost unlimited sales market, capable of absorbing any quantity of products produced.
In addition, these products do not spoil and officially have an infinite shelf life.
The profitability of table salt production may seem low, primarily because of its price, but this is a false feeling: such a business will pay back any investment in the shortest possible time.
Technology and equipment for the production of table salt
Despite its apparent simplicity - rock salt itself is mined in almost pure form - the production of table salt requires a certain set of properly installed and configured equipment, the correct operation of which determines the quality of the resulting product and, ultimately, the profitability of the enterprise as a whole.
In this case, we will consider two equipment options with similar indicators: raw material costs 1100-1150 kg per ton of product; water consumption 90-150 liters per ton of product; energy consumption of 20-30 kW/h per ton of product; fuel consumption (coal, gas, diesel) of 10 kg per ton of product and a staff of 2-5 people.
Both lines are manufactured in China by different manufacturers and differ, except for the price - 1,600,000 yuan (about 7.77 million rubles) in the first case and 2,300,000 yuan (about 11.17 million rubles) in the second - in the range of products: the first line produces coarse table salt, and the second, both coarse and fine (so-called “extra”) iodized or without added iodine - i.e. There are only 4 types: large iodized, large without added iodine, small iodized and small without added iodine.
In addition, during the explanation of the technology for producing table salt, all prices for individual components of the production line will be given for a rough estimate of the cost of self-assembly.
As you know, no mineral is found in its pure form. Halite is no exception: foreign inclusions in the form of earth, sand, stones, metal parts, etc. - a common occurrence for him.
Therefore, when raw salt arrives at a processing plant, it goes through several stages of purification: two washes of different types of devices followed by crushing (for coarse salt - one) and two without crushing (for coarse salt - one).
In addition, a special magnetic separator filters out metal impurities.
For the equipment of the first stage of processing you will need
- hopper for raw salt with a capacity of 5 cubic meters. m (price – 29,000 yuan, or about 140.9 thousand rubles),
- spiral conveyor (price – 28,000 yuan, or about 136 thousand rubles),
- belt conveyor (price – 52,000 yuan, or about 252.6 thousand rubles),
- magnetic separator (price –5,000 yuan, or about 24.3 thousand rubles),
- spiral salt washer (price – 78,000 yuan, or about 378.9 thousand rubles),
- roller crusher (price - 82,000 yuan, or about 398.3 thousand rubles),
- interfering salt washer (price – 73,000 yuan, or about 354.6 thousand rubles),
- special industrial pump for salt (price – 41,000 yuan, or about 199.2 thousand rubles),
- brine tank (price - 14,000 yuan, or about 68 thousand rubles)
- and two brine pumps (price - 12,000 yuan each, or about 116.6 thousand rubles for both), equipped with a special seal resistant to aggressive (salt) environments costing 3,000 yuan, or 14.6 thousand rubles.
The salt, cleared of foreign impurities, is dried using an industrial centrifuge (265,000 yuan, or about 1287.3 thousand rubles).
Then, depending on the selected type of product, the semi-finished product is sent either to a unit for adding iodine (43,000 yuan, or about 208.9 thousand rubles) to obtain iodized salt, or through an additional spiral conveyor (41,000 yuan, or about 199.2 thousand rubles) directly into vibration drying (145,000 yuan, or about 704.4 thousand rubles) - to obtain coarse iodized salt and coarse salt without adding iodine.
If the selected type of table salt is fine, then after passing through a unit for adding iodine and vibration drying, it undergoes additional crushing on a roller crusher (72,000 yuan, or about 349.8 thousand rubles).
Just as in the previous case, the iodization step is optional - depending on whether the fine salt should be iodized or not, it is added or excluded in manufacturing process.
The final drying of the salt is carried out using hot air generated in a furnace (150,000 yuan, or about 728.7 thousand rubles), pumped using an industrial fan (19,000 yuan, or 92.3 thousand rubles).
However, the list of drying equipment is not limited to just these two items: in addition to the blower, you also need a cooling fan (5,000 yuan, or about 24.3 thousand rubles), an exhaust air hood (18,000 yuan, or 87.4 thousand rubles) .), additional 3 sets of spiral conveyors (41,000 yuan each, or about 597.5 thousand rubles for all) to move salt between units, a rotating sieve for separating salt fractions that do not meet the size standard for fine salt (84,000 yuan , or about 408 thousand rubles), as well as a dust remover (34,000 yuan, or about 165.2 thousand rubles), respectively, for salt ground into dust, which also should not be present in the final product. At the same stage, other excipients are added to the salt (also optionally), for example, potassium ferrocyanide (E536 in the European food additive coding system) - a non-toxic complex salt - as an anti-caking agent for table salt.
In addition, it is possible to add other excipients - up to approximately 97-98% sodium chloride content.
Most often, iodides, carbonates are added, and Lately– fluorides. Fluoride supplementation, for example, is used to prevent dental disease.
After adding auxiliary substances, another spiral conveyor (41,000 yuan, or about 199.2 thousand rubles) delivers the finished salt of both types to a special bunker (39,000 yuan, or about 189.4 thousand rubles), from where they go for a semi-automatic packer (85,000 yuan, or about 412.9 thousand rubles), and then to a box packaging line (5,000 yuan, or about 24.3 thousand rubles) and, after passing the automatic control check measuring instruments (scales, checking the quality of individual and group packaging, etc., a line with a total price of 6,000 yuan, or about 29.1 thousand rubles) are shipped to the finished products warehouse.
The above list of equipment for the production of table salt is complete. But additional components and parts are not listed, the task of which is to link parts of the line together.
These include:
- electrical wire connecting devices (105,000 yuan, or about 510.1 thousand rubles),
- thermal insulation material (26,000 yuan, or about 126.3 thousand rubles),
- valves for connecting pipes (35,000 yuan, or about 170 thousand rubles),
- coil (10,000 yuan, or about 48.6 thousand rubles),
- set of connecting pipes (3,000 yuan, or about 14.6 thousand rubles)
- and the control panel itself (75,000 yuan, or about 364.3 thousand rubles).
Regarding ready-made lines, we can say that their purchase (as a rule, together with the assembly service, usually carried out by specialists from the manufacturing enterprise) will cost quite a bit more than a line purchased as separate units and assembled on its own.
On the other hand, in at this moment there is also a minus: by purchasing units one by one, it is easier to choose more reliable units for the most critical sections, while the quality of the units present in the line set corresponds to the quality of the worst of them - after all, if it fails, the entire technological chain will stop, the strength of which depends on the strength of its weakest link.
The productivity of one line is 1 ton per hour (net weight, i.e. without packaging), so at first one-shift work is possible, but then, as the business develops, it is possible to switch to two or three shifts.
Prospects for the development of the table salt production business
Almost all prospects for the development of salt production are prospects for a linear expansion of the volume of output. But in fact, that's not all.
Firstly, there is now (in Russia still weakly) a small market trend – the so-called. “salt with low sodium content” (eng. low sodium salt). Most of these products are a mixture of sodium chloride with potassium or magnesium chlorides. It is possible to launch such production.
Another promising area is parallel launch chemical production: Table salt is also used to produce soda, chlorine, hydrochloric acid, sodium hydroxide and sodium metal.
In addition, if your deposit contains not only halite, but also sylvinite, then it is possible to slightly retrofit the production by equipping the main line with an auxiliary one: sylvinite is a raw material for the production of potassium chloride, which is used as an agricultural fertilizer.
Productivity 1 t/h. Salt (sodium chloride) is important element, ensuring the life activity of humans and the animal world. Since ancient times, salt production has been considered a profitable and noble business.
We invite you to choose the complete set of a salt production plant that best meets your requirements.
We have three factory configurations: Econom, Standard and Full.
Distinctive features of the Econom package are maximum use of conditions natural environment. This plant has low energy consumption. Technological process susceptible to changes in conditions environment. Reacts negatively to changes or deterioration in the chemical composition of salt, incl. insoluble impurities. The products produced have variable quality and a high level of manual labor. Requires constant quality control. The production cycle of finished products is 7-14 days.
The Standard package is the optimal offer for manufacturers working on raw materials with high characteristics of the feedstock. This configuration uses the method of double purification of raw materials, which allows the production of products High Quality. The line is semi-automatic. Has a low manual labor ratio. The production cycle is 4-6 hours. The manufactured products comply with GOST, and also allow us to trade with large federal customers and sell salt for export to the countries of the former CIS.
The Full package has the highest automation coefficient. Product production is based on the method of deep processing of raw materials. This line is susceptible to severe contamination, which allows trading with major foreign customers. The production cycle is 4-6 hours. Production complies with ISO quality standards. Finished products complies with GOST. This configuration allows you to trade with large federal customers and sell salt for export to the countries of the former CIS, as well as countries of the near and far abroad.
Layout of the Econom equipment plant
Plant layout for Standard and Full configurations
Conclusion: from the point of view of return on investment, the Econom configuration line looks the most attractive. It has the smallest amount of initial investment, with the fastest return on investment Money. However, when choosing a configuration, it is also necessary to take into account the dependence of the production process on external factors.
Standard and Full configuration plants are an order of magnitude more resistant to changes in external factors, and therefore have a more stable production process. This, in turn, allows us to achieve consistent high quality products and, as a result, the opportunity to trade with large customers.
The client needs to independently assess the market he is going to work in and who his potential client is. Next, based on this, choose the most suitable package for yourself.
Salt production- a very good business idea. Salt is always a popular and fairly liquid product that practically does not spoil, has constant demand and an endless shelf life. All these qualities indicate that salt is an ideal product, and processing salt and its subsequent sale is a good and profitable idea to start your own business.
But the production process directly depends on the type of salt itself.
One of the most useful is sea salt. It contains various very beneficial minerals. Sea salt is obtained by evaporating sea water, because it contains a huge list of salts with various additives.
If you do production of table salt, then in this case it is necessary to think carefully business plan
.
In order to obtain table salt, you need halite, or rock salt. Basically, halite deposits are first developed, and then, after a whole specific processing process, table salt is obtained from the extracted rock salt. But besides this method, evaporation of salt from salt water is also practiced. This can be either sea water or water from saline bodies of water - lakes or ponds. However, this alternative method becomes cost-effective only in cases of a large number of the above-mentioned reservoirs.
Halite is the mineral from which table salt is made. It, like any mineral, contains foreign inclusions in the form of sand, earth or some metal parts. For this reason, once raw salt arrives at a plant, it first goes through several purification steps. First, it is washed twice with various types of devices, then it goes through the crushing stage, and at the end it is washed twice again. In this case, a magnetic separator sifts out metal impurities that may be in the halite. After the salt has passed the stage of purification from foreign impurities, it is dried using a special centrifuge.
In order to obtain coarse iodized salt, the resulting semi-finished product is sent to a unit for adding iodine, and then to vibration drying. If coarse salt should not be iodized, then the step of adding iodine is skipped, and the salt goes directly into vibration drying. If fine table salt is needed, then after the semi-finished product has gone through the stage of adding iodine and vibration drying, it is sent to the crusher. If fine salt does not need to be iodized, then this processing step is excluded from the production process.
After the process of adding iodine and crushing, the salt is dried. This happens with the help of hot air, which is pumped into the oven by an industrial fan. Also, at this stage you can add other excipients. These may be some food additives that resist caking of table salt, iodides, carbonates, fluorides. Fluoride supplementation is beneficial in preventing dental disease. At the same time, the total amount of food additives in salt should not exceed 2-3% (as a percentage).
Once all the excipients have been added to the salt, it is completely ready for packaging.
Video - how sea salt is mined and produced:
Unpurified brine from the brine production facility continuously flows into the crude brine tank pos. E18 with a capacity of 2000 m3. From the reservoir with centrifugal pumps type X 200-150-400 pos. H29 is supplied for heating to a group of heat exchangers. In heat exchangers pos. T4 brine is heated to 40°C due to the heat of the condensate of the secondary steam of the evaporators.
Having passed the heating unit, the brine enters the central part of the settling tank stabilizer, pos. X10, where it is mixed with a soda-caustic reagent and a PAAG working solution. The piping scheme for settling tanks provides for their operation in autonomous and sequential mode. The soda-caustic reagent is supplied in an amount of 0-8 m3/hour.
After mixing the crude brine and the caustic soda reagent, poorly soluble compounds are formed: calcium carbonate CaCO3 and magnesium hydroxide Mg(OH)2. The solubility of calcium carbonate decreases with increasing temperature and therefore, to reduce the residual content of calcium ions, it is recommended to purify the brine at a temperature of 30-40ºC. In addition, with increasing temperature, larger and more easily settling calcium carbonate crystals are formed, which is very important for the subsequent settling of the brine.
The purified brine must contain:
CaI+ ions no more than 0.05 g/dm³;
MgI+ ions no more than 0.04 g/dmі;
excess СО3ІЇ no more than 0.15 g/dmі;
excess OH is not more than 0.1 g/dm3.
In the settling tank, CaCO3 and Mg(OH)2 are formed and the brine is clarified from these sediments. Single-tier settling tanks with a central paddle drive and a central input of the settled liquid.
Through a drain funnel installed in the upper peripheral part of the drain chute of the settling tank (in sequential operating mode), the clarified brine flows by gravity into the purified brine tanks pos. E20 with a capacity of 2000 m3 each.
To intensify the settling process of the purified brine, PAAG is used with a working concentration of 0.001-0.1%, which is supplied to thickener settling tanks by pumps pos. H30. Sludge from the settling tanks, thickening, continuously descends into the sludge collection pos. E19. Sludge from collectors, partially diluted with water 1:10 to a solid phase concentration of up to 18%, goes to a sludge storage facility.
Brine purified from calcium and magnesium salts in an amount of up to 240 m3 from tanks using centrifugal pumps type X280/29T pos. H32 is supplied to the evaporation department and in an amount of 25-100 m³ per shift to the reagent department for the preparation of reagents.
The evaporation department has three evaporation units, including one backup.
Initial purified brine in an amount of up to 240 m3/hour (based on two working evaporation units) with a temperature of 18-35ºC from tanks with pumps type X 280/29-T pos. H32 is supplied to the nutrient tanks pos. E21 with a capacity of 100 m³ each, part of the purified brine in the amount of 25-40 m³/hour is sent to the centrifugation department for washing the salt in Brandeis thickeners and centrifuges.
The feed tanks also receive recirculating mother brine in the form of part of the discharge from Brandeis thickeners and centrifuge centrifuge.
A mixture of the initial purified brine with the recirculating mother brine necessary for removing the solid phase from the installation, called feed brine, is supplied respectively to each evaporation unit, pos. K6 in parallel to all evaporators.
Before being fed into the evaporator, the feed brine is heated in a shell-and-tube heat exchanger pos. T5 with a heat exchange surface of 75 m².
Heating of the feed brine before feeding it into 1 evaporator of the evaporator unit is carried out by condensate of the heating steam of 1 housing and secondary steam of 2-4 housings. The brine moves through the pipe space, condensate from the heating chambers moves through the interpipe space. The main flow of the feed brine is supplied to the irrigation rings located in the upper part of the separators of the evaporators; a small part of this brine in the amount of 2-4 m3/hour is supplied to each of the surge tanks to prevent the deposition of table salt on them.
During evaporation in the apparatus, crystallization of table salt occurs, and the flow rate of the supply brine into each apparatus is set so that the mass fraction of the solid phase in the evaporated suspension (pulp) of each evaporator is equal to 30-40%. When the mass fraction is below 30%, the cost of heating steam to obtain salt increases and salt deposits form on the walls of the separator of the evaporator, which leads to a reduction in the inter-flushing period of operation of the evaporator. At a mass fraction above 40%, heat transfer in evaporators deteriorates and the productivity of the evaporation unit decreases, in addition, the size of table salt crystals decreases.
The evaporated pulp flows from body to body by gravity through the overflow tank. This is facilitated by a consistent decrease in pressure throughout the housings. A decrease in pressure leads to partial self-evaporation of the solution in subsequent housings and additional release of secondary steam in them.
From the fourth (last) evaporator, production salt pulp containing 30-40% wt. crystalline table salt, in the amount of 60-90 m3/hour with a pump type GrT 160/31.5 pos. H31 is pumped into the centrifugation department into Brandeis type thickeners, pos. X11.
The pressure in the heating chamber of the first evaporator is maintained in the range of 0.15-0.22 MPa. Steam consumption per evaporation unit is up to 30 t/hour.
Secondary steam from the first evaporator enters the heating chamber of the second evaporator, the pressure in which should not exceed 0.7 MPa. Subsequent evaporators are heated by secondary steam from the previous evaporator. From the fourth evaporator, secondary steam enters a barometric condenser with a diameter of 2.0 m.
The condensate of the heating steam from the first evaporator is cooled in heat exchangers, then pumped to the boiler room.
The secondary steam condensate from the heating chamber of the second evaporator enters the heating chamber of the third evaporator, and then from it into the heating chamber of the fourth evaporator, from where it is supplied for other production needs.
To utilize vapors and non-condensed gases in barometric condensers, recycled water with a temperature not exceeding 28°C is used. Heated water from barometric condensers enters tanks - hydraulic seals with a capacity of 10 m3 each with a temperature not exceeding 50 ° C and is then supplied to fan cooling towers. The chilled water is collected in a cold water receiver and is sent for vapor recovery in barometric condensers.
Non-condensable gases from the heating chamber of the first evaporator are discharged into the heating steam pipeline of the second evaporator. From the heating chamber of the second evaporator, non-condensable gases are discharged into the heating steam pipeline of the third evaporator, from the third heating chamber into the heating steam pipeline of the fourth evaporator, and from the fourth heating chamber into the barometric condenser. The outlet is carried out through a central pipe located in the interpipe space of the heating chamber.
Thickening of salt pulp from 30-40% to 40-60% of the mass. the solid phase is carried out in thickeners of the Brandes type, and the separation of the solid phase is carried out in horizontal filter centrifuges of type S FGP 1201T-01 pos. Ts23 with pulsating sediment unloading. Washing the salt from the mother brine is done with purified brine in Brandeis type thickeners. The consumption of purified brine for washing is 25-35 m 3 /hour. Washed and centrifuged salt with a moisture content of 2-3% wt. enters conveyor belts. Wet salt on the conveyor is treated with a solution of potassium ferrocyanide (PFC) as an anti-caking additive.
The FCC solution is prepared in a tank, into which a sample of crystalline potassium ferrocyanide, condensate and compressed air are supplied to mix and dissolve the FCC. From the tank, the FCC solution flows by gravity through a pipeline through nozzles to the wet salt conveyor, pos. PT 24. Passing along the conveyor, the salt is partially mixed and supplied for drying.
The flow rate of the FCC solution is regulated automatically, depending on the amount of salt entering the conveyor. Salt consumption is determined using scales (indicator scales) on the conveyor.
Wet table salt containing 2.5 ± 0.5% wt. H2O and a temperature of 40 ±5 °C are distributed by conveyors into bins pos. X12. From the bunker, table salt is fed by a feeder and a mechanical thrower into the “fluidized bed” apparatus, pos. T3, where salt is dried with hot air. Air is supplied to the apparatus by a pipe-gas blower after preheating in the air heater pos. T1.
Air is supplied to the air heater in an amount of 11000 ± 2000 nm/h per drying unit at a pressure of 4000 ± 500 Pa.
In the air heater, the air is heated by flue gases from the combustion of natural gas in burners of the GMG type - 2 M furnace pos. T 2. When the gas is turned off, high-sulfur fuel oil grade M-100 can be used as fuel. Before combustion, fuel oil is heated with steam at a pressure of 0.6 MPa to 120°C. Air for combustion of fuel oil, gas (to the burner), for cooling of the furnace roofs and after-combustion is supplied by a VDN type fan - 11.2 pos. At 33-34 under a pressure of 2000 ±500 Pa. In this case, the air consumption for the burners is 5000 ± 1000 nm/h, and for blowing the roofs and afterburning - 1600 ± 200 nm/h.
The combustion of natural gas or fuel oil in the furnace occurs at a vacuum of 50 ± 20 Pa and a temperature of up to 1300°C. The specified vacuum is maintained by a smoke exhauster pos. B36.
A decrease in vacuum can lead to the release of hot flue gases into the room; an increase in vacuum leads to increased suction of cold air into the firebox, which can lead to a torch failure.
Flue (smoke) gases in the mixing chamber of the firebox pos. T2 is mixed with waste (after the air heater) return flue gases having a temperature of 180 ± 10°C. As a result of mixing, the temperature of the flue gases decreases to 550 ± 50°C, at this temperature they enter the pipe space of the air heater through underground ducts to heat the drying agent, where they are cooled from 550 ± 50°C to 180 ± 10°C, and are pumped into the packed adsorber pos. K8, where gases are purified from sulfur-containing compounds, after which the latter are purified by a smoke exhauster type DN - 12.5 N = 75 kW, n = 1500 rpm with a capacity of 37,000 m³/h pos. X13 is emitted into the atmosphere through a common flue and two chimneys with a diameter of 600 mm. The height of the first chimney is 45 m, the height of the second chimney is 31.185 m. A decrease in the temperature of the flue gases below 170°C leads to the formation of acid corrosion of gas pipelines and chimneys, and an increase in temperature above 200°C leads to failure of the smoke exhauster. Part of the cooled flue gases is supplied by the same smoke exhauster to the mixing chamber of the firebox to maintain their temperature in front of the air heater in the range of 550 ± 50°C.
Adsorber pos. K8 is irrigated with soda. The resulting wastewater sent to the industrial waste collection pos. E16, from where they are discharged into the sewer.
Dried table salt from the "KS" apparatus through the overflow chute is supplied to the "KS" apparatus for cooling. Cooling air is supplied to the device by a fan. Chilled table salt is unloaded onto the conveyor pos. PT27, from where it is supplied to vertical elevators type TsG - 400 pos. PT28 and further to electromagnetic vibrating screens to separate the pellets formed during drying.
Large salt particles (more than 1.2 mm) and lumps that did not pass through the holes in the sieve fabric of vibrating screens pos. E22, leave it and, by gravity, in an amount of 320 ± 50 kg/h enter a vertical mixer with a capacity of 10 m³ to dissolve the pellet, pos. E14.
The resulting solution in an amount of 3-6 m and 5-10% is pumped out by pumps type AX 45/54 into the industrial waste collector, pos. E15.
At the unit for transferring salt from vibrating screens to conveyors, magnetic traps are installed. The installation was carried out in 2 tiers: the top -3 magnets, the bottom -4 magnets. The main flow of salt with particle sizes less than 1.2 mm is supplied to inclined belt conveyors KLS - 800 positions. PT26, supplying salt to the salt packing and packing shop.
The dusty air leaving the "KS" apparatus enters the gas cleaning system. Cleaning is carried out in two stages: preliminary cleaning of the largest particles is carried out in cyclones pos. K7 and cleaning from fine dust particles in a bag filter pos. F9.
The spent drying agent with = 70 ± 10°C and dust content of 12-50 g/nm under a discharge of 200 ± 50 Pa is supplied to the battery cyclone for cleaning. Air purified in a battery cyclone to a concentration of 12-17g/nmі t=68±8єС in the amount of (16±4)x10і nmі/hour under a discharge of 1500±500Pa is sucked in by a fan pos. B35 and is supplied under a pressure of 4500±500 Pa for cleaning into a bag filter.
Salt dust is removed from the battery cyclones using chutes equipped with flashing lights (sluice gates) and fed into the container pos. E17, where recycled water flows. The resulting saline water is directed to a pit located in the brine field. Fine dust collected in a bag filter is fed to a belt conveyor pos. PT25, from where it enters the pellet washout tank.
The spent drying agent, finally cleared of the smallest particles of salt dust, at a temperature of 110°C is supplied to the air heater pos. T1, where it is heated to a temperature of 300°C and returned to the “KS” dryer.
The process flow diagram for the production of sodium chloride is presented in Appendix C.
Loading...