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Usmonov Rasul Muratovich, aspirant (PhD) of Institute of General and Inorganic Chemistry
of the Academy of Sciences of Uzbekistan Uzbekistan, Tashkent
Salikhanova Dilnoza, doctor of technical sciences, senior head Scientist of Institute of General and Inorganic Chemistry of the Academy of Sciences of Uzbekistan Uzbekistan, Tashkent
Kuldasheva Shaxnoza Abdulazizovna, doctor of Chemical sciences, senior head Scientist of Institute of General and Inorganic Chemistry of the Academy of Sciences of Uzbekistan Uzbekistan, Tashkent
Eshmetov Izzat, head of laboratory of Institute of General and Inorganic Chemistry of the Academy of Sciences of Uzbekistan Uzbekistan, Tashkent Abdurakhimov Saidakbar, doctor of technical sciences, professor, Tashkent Chemical-Technological Institute, Uzbekistan, Tashkent
CLEANING OF WASTE WATER FOR FATTY PRODUCTION BY WASTE OF SUGAR PRODUCTION-DEFECATE
Abstract: This article the possibility of using a waste of sugar production - defecate for the neutralization of waste water in the fat and oil industry is proved. The optimum amount of introduced defecate is determined, which is 1.2-1.6% depending on pH. Comparative data of defecate and cul-cated soda used to date in enterprises have been compiled. It is established that the use of defecate as a reagent to neutralize acid waste water leads to the prevention of its accumulation in the form of waste in large quantities, to eliminate the negative impacts of it and acid waste water on the environment and equipment.
Keywords: defecate, waste, acid waste water, calcined soda, neutralization, purification, indicator, pH.
The Oil and fat industry (O&FI) is the leading different surfactants. Purification of such waters by
branch of the food industry in Uzbekistan, where traditional methods entails considerable losses of
large quantities of purified water are used to flush both material and energy resources. vegetable oils, salmons, etc. Wastewater is formed, It is known that the waste water of the Oil and
which contains fats, fatty acids, phosphatides and fat industry (O&FI) contains mainly organic com-
pounds in the form of emulsified fat-containing substances (vegetable oils, free fatty acids, phosphatides, soaps, etc.) and are characterized by a low concentration of the dispersed phase in the dispersion medium, so that they are relatively stable.
Therefore, for effective cleaning them is necessary to know the composition and the amount of pollution and the sources of their formation. As seen wastewater treatment of enterprises of fat and oil industry requires the use of different methods.
At the same time, the waste treatment of fat-containing and fat-free drains is mandatory in the purification scheme. Moreover, preliminary cleaning is mandatory before discharge of sewage into the sewage system. It consists in the allocation and removal of fat by means of greasers arranged in the type of oil traps [1].
In practice, the formed wastewater, containing mineral acids is neutralized and adjusted to pH
Table 1. - The main physical properties of the de
6.5 - 8.5. Neutralization with the use of NaOH, KOH, Na2CO3, CaCO3, MgCO3, CaCO3 and etc. are considered the most common method. At the same time, calcium hydroxide with an active lime content of 5-10% is considered the cheapest neutralizer of acid waters. It should be noted that during the preparation of lime milk, quenching, lime is associated with significant energy costs. In addition, hydrated lime has a corrosive property and leads to rapid deterioration of the equipment. Therefore, in most cases, calcined soda is used as a reagent to neutralize acidic waters [2]. The disadvantage of the latter is its high cost.
Consequently, the replacement of expensive imported reagents with cheaper and more affordable is considered an urgent task. To this end, we proposed a defect - a waste of sugar production to neutralize the acid waste water of calcined soda (O&FI).
cate obtained from the sugar plant in Uzbekistan
humidity, % Density, kg/m3 Specific volume kg/m3 pH Oil absorption
18.0-24.02 912.1-910.8 1030-1180 8.5-8.7 19.00-21.4
From (Table 1). It can be seen that the humidity, specific volume and Oil absorption of defecate varies within wide limits, which is related to the quality of processed raw materials, deviations in processing technology, etc. As seen from (Table 1) pH, and other indicators greatly exceed the maximum allowable concentration (MAC) limit. This once again proves that such water must be neutralized and cleaned of related substances.
Therefore, when using a defecate in the treatment of sewage water O&FI it is necessary to use averaging capacity, where the above-mentioned indicators are stabilized.
Table 2. - Chemical composition of waste
We have studied this process with the use of the recommended defecate in neutralizing the acid waste water generated at "Urgench yog-moy" when decomposing sopstok with sulfuric acid. Table 2 presents the results of analyzes of the chemical composition of sewage collected in the soap processing workshop.
It can be seen from (Table 2) that in the sewage water of the "Urgench-yog-moy" corporation, the greatest number of cations of the type Ca2+ and Mg2+, and anions of the SO42- and Cl- type. This suggests that this wastewater has a complex chemical composition, for the purification ofwhich it is necessary to use a polyfunctional sorbent.
water of "Urgench yog-moy" corporation
The content of the wastewater
Cations mg/l mg - eq/l % - eq/l
1 2 3 4
Na+ 21 0.91 17
We have studied other standardized water quality indicators, the data of which are presented in Table 3. Table 3. - Standardized indicators of waste water of "Urgench yog-moy"corporation
1 2 3 4
K+ 2 0.05 1
NH + 5 0.28 5
Ca2+ 41 2.05 38
Mg2+ 24 2.0 38
Fe3+ 1 0.05 1
Fe2+ 0.2 0.01 -
Total: 94.2 5.35 100
Anions mg/1 mg-eq/1 %-eq/l
Cl- 87 2.5 16
so,2- 638 13.30 83
no2- < 0.01 - -
NO3- 3 0.05 -
CO32- no - -
HCO3- 11 0.18 1
Total: 739 16.03 100
Indicators of water unit measurement values
Rigidity: mg-eq/1
Overall 4.3
Carbonate 1.75
Non-Carbonate 2.55
pH Free CO2 mg/1 11.0
Oxidizing properties 02 mg/1 not found
Content:
SiO2 mg/1 2.0
H2S mg/1 is absent
From (Table 3) it can be seen that the sewage water of the "Urgench yog-moy" corporation is strongly rigid with a high content of non-carbonate compounds. This is confirmed by a pH of 1.8. Although this wastewater is apparently colorless transparent, with a taste of fresh water and a pungent odor.
We neutralized the acid waste water with the defecate by a dry process [6]. Defecate was added to the stock with the above composition in an amount of 1.2-1.6%, depending on the pH. During its addition, a rapid evolution of carbon dioxide was observed to
form a stable foam. The neutralization process, with the release of the flocculent sediment, was continued for 15 minutes. After neutralization, the wastewater had a pH of 6.8 4- 7.2, which is close to a neutral medium.
It is known that sewage effluents, when neutralized with lime, give abundant and strong gypsum deposits, which are separated by the method [4]. There are also works on the prevention of gypsum deposits, stabilization of the solution by increasing the solubility of gypsum with the addition of acetone and lower alcohols [5].
In our case, after neutralization, turbidity is observed in the mixture and after 1 hour from the moment of addition of defecate a slight flocculent deposit appears, which does not clog the pipes. CaSO4 could be formed in a sufficient amount, capable of producing gypsum deposits, since the main reaction of neutralization proceeds according to the scheme: CaCO3+H2SO4^CaSO4|+CO2T+H2O Here precipitation in large quantities is likely prevented by strong foaming of the mixture due to the formation of CO2 bubbles f. On the other hand,
the presence of pectic and other organic substances in the mixture improves the solubility of gypsum and prevents the precipitation of CaSO4 [4]. After neutralization, the runoffhas the following chemical composition, given in (Table 4).
As can be seen from Table 4. After neutralization with the use of a deficiency, the pH is 6.6-6.9, and SO42- is reduced by a factor of 10. up to 62 mg/l. These data confirm the expediency of using the waste of sugar production-defecate as a reagent to neutralize wastewater.
Table 4. - Indicators wastewater after neutralization defecate wastes of sugar production
Parameters, mg/l
pH Na+ Ca2+ Mg2+ Cl- SO 24 HC°3- Organic impurity
6.6-6.9 28 64 22 82 62 36 14.56
For comparison, we conducted studies of the effect of calcined soda in the neutralization of sewage of the (O&FI) corporation. "Urgench yog-moy", where the neutralization reaction proceeds according to the following scheme:
Na2CO3+H2SO4^Na2SO4+CO2î+H2O As can be seen from the equation, when a sodium sulfate is used, no precipitate is formed in com-
parison with the defecate, and the sodium sulfate itself remains dissolved in the waste water. It has been established that the optimum amount of soda ash to be introduced, which is between 0.8-1.2%, depending on the pH. The data obtained are shown in (Table 5).
Table 5. - Main indicators of sewage after neutralization of Na?CO„
Parameters, mg/l
pH Na+ Ca2+ Mg2+ Cl- SO2- 4 HCO3- Organic impurity
6,8-7,1 3493 44 19 87 646 213 8.2
As can be seen from table 5, the pH is lowered to 6.8-7.1, but the amount of sodium ions is increased by several hundred times. In addition, HCO3 also increases by 20 times. If such water enters the soil, it becomes very saline, which will lead to an environmental problem. Therefore, it is not advisable to use it to neutralize waste water.
On the contrary, the use of a defecate to neutralize acidic wastewater has a significant economic effect due to substitution of expensive reagents, en-
vironmental protection, and also to an increase in the service life of equipment, water treatment plant systems, and etc.
Thus, the use of defecate as a reagent to neutralize the acid waste water of the Oil and fat industry (O&FI) leads to the prevention of its accumulation in the form of waste in large quantities, to eliminate the negative impacts of it and acid waste water on the environment and equipment.
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3. Sapronov A. R. Techno1ogy of sugar production. - M.: Ko1os, 1998. - 432 p.
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5. Ac. USSR, IPC 02S5 / 02. Vau1in VE-437720 / 25-08; Dec1ared 23.11.70; Opub1. 30.03.71. Bu1. 12. - 2 p.
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