SU1605089A2 - Method of thermal neutralization of waste in different aggregation states - Google Patents

Abstract

The invention may be used in the chemical, petrochemical, and other industries of the industry. The aim of the invention is to increase the efficiency of disposal of waste containing chlorine, fluorine, sulfur and phosphorus compounds. During thermal decontamination of various aggregates of waste, evaporation of watered waste is carried out by bubbling through them the combustion products of fuel and waste with the formation of a foam layer and a settling zone. Liquid watered waste and a neutralizing additive are supplied to the foam layer in an amount necessary to maintain in a settling zone an environment with a pH of 8-10. The bottoms are removed from the settling zone. From the resulting vapor-gas mixture, the droplet entrainment is separated and sent to the settling zone, and the vapor-gas mixture is burned out with a periodic change in the direction of movement of the gas flow to the opposite. Heat recovery is carried out by alternately contacting the gas-permeable heat-accumulating nozzle with the flue gases from the afterburning stage and the vapor-gas mixture supplied to the afterburning. 1 il.

Description

The invention relates to methods of thermally removing waste, can be used in the chemical, petrochemical, and other industries and is an improvement on the invention in the main author. Ev, No. 1015189.

The purpose of the invention is to increase the efficiency of disposal of waste containing compounds of chlorine, fluorine, sulfur, phosphorus.

The essence of the method lies in the fact that the evaporation of the flooded liquid waste is dried; the combustion of fuel and waste products by bubbling through them with the formation of a foam layer and a settling zone, in the foam layer under the liquid watered waste and a neutralizing additive in the amount necessary for Keeping in the settling zone of the environment with a pH of 8-10, and the distillation residue is removed from the settling zone, the droplet entrainment is separated from the vapor-gas mixture and sent to the sediment zone, and the steam-gas mixture is burned at a periodic nenii direction of flow of the gas is reversed, the heat recovery is carried out by alternately heat accumulating gas permeable contact nozzle with the off-gases from the afterburning stage and supplied to the afterburning of the gas-vapor mixture.

oh oh oh

oe yu

Yu

Evaporation of watered waste in the foam layer created by bubbling fuel and waste products through them, and adding a neutralizing additive (alkalis, carbonates of alkaline and alkaline earth elements, oxides and hydroxides of alkaline earth elements) into the foam layer, allows efficient evaporation in small volume and simultaneously bind acidic components contained in combustion products and waste (HCI, S02, P205, etc.) into mineral salts.

Evaporation in the foam layer created by bubbling through the watered liquid waste products of the combustion of fuel and waste, allows to intensify the evaporation process, and the addition of a neutralizing additive to the foam layer reduces its consumption and intensifies the neutralization process.

Maintaining a medium with a pH of 8-10 allows for a reduction in specific neutralized consumption. additive with a high degree of binding of acid components of gases. Maintaining the environment with a pH of 8 leads to an increase in the concentration of acidic components in the vapor-gas mixture. Maintaining a medium with a pH of 10 does not reduce the concentration of acidic components in the vapor-gas mixture and only leads to an increased consumption of neutralizing additive due to the removal of excess neutralizing additive with the residue.

Removing the bottoms from the settling zone allows for the removal of the bottoms with a high content of organic and mineral water.

. The formation of a settling zone during the barrage of combustion products through flooded liquid waste allows an increase in the content of organic and mineral substances in the removed bottom residue in comparison with the foam layer.

Separating the drip from the gas-vapor mixture allows reducing the removal of organic and mineral substances by the gas-vapor mixture and reducing their introduction of a gas-permeable heat-retaining nozzle.

Feeding the drift entrainment to the settling zone allows reducing the entrainment of the solid phase from the evaporator.

The burning of the vapor – gas mixture with a periodic change in the direction of the gas flow movement to the opposite with the heat recovery of the exhaust gases by means of alternate contact with the heat-accumulating nozzle of the exhaust flue gases and the afterburning

-

the gas-vapor mixture allows the most complete regeneration of heat and effectively neutralizes waste containing chlorine, fluorine, sulfur, and phosphorus compounds in the gas-vapor mixture.

The drawing shows the installation for implementing the method.

The installation comprises a furnace 1 for burning waste and fuel, connected downstream of the gas path to the evaporator 2, the smoke exhauster 3, the switching device 4, the burner 5, the smoke exhauster 6 and the chimney 7;

Evaporator 2 in the waste supply line

15 coeAi / weH with a furnace 1. The evaporator 2 contains the region of formation of the foam layer 8, the settling zone 9, the droplet separator 10 with the device 11 for returning the liquid phase. Afterburner 5 contains gas permeable

20 layers of the nozzle 12, the vortex chamber 13 and the burner 14,

The method is carried out as follows.

25Solid, pasty and liquid wastes containing chlorine and (or) fluorine, and (or) sulfur, and (or) phosphorus, and, if necessary, fuel, are burned in the furnace 1. Liquid watered waste is supplied to the foam layer 8 using steam 2, in of which a part of the moisture is evaporated due to direct heat exchange with the flue gases leaving the furnace. Neutralizing additive is added to the liquid o watered waste or directly to the foam layer in an amount necessary to maintain in the settling zone 9 of the medium with a pH of 8-10.

The bottoms from the settling zone 9 of the evaporator 2 are sent for incineration into

40, the furnace I or utilize the vapor-gas mixture formed in the foam layer after separation of the liquid phase in the droplet separator 10 is directed by means of the smoke exhauster 3 to the switching device 4. The liquid phase from

45 droplet separator 10 through the return device 11 is fed to the settling zone 9. The vapor-gas mixture from the switching device 4 is fed to the afterburner 5. The afterburning is carried out in a swirling gas flow in the vortex chamber 13 with a periodic change in the direction of its movement to the opposite using the switching device 4 with heat recovery waste gas mx by means of alternate heat exchange of gas permeable nozzle 12 with waste gas 1-, with the afterburner gases and supplied S, the burner vapor-gas mixture. The required temperature regime is maintained by burning the fuel supplied to the burner for km 14.

the afterburner gases are removed by the exhauster 6 through the chimney to the atmosphere.

Example 1. Waste containing organochlorine substances is subjected to thermal neutralization. Solid, paste-like and liquid wastes with a high content of organic substances and vat residue after evaporation of waste water are burned in a furnace. Flue gases with a temperature of 1200 ° C are removed from the furnace, mixed with a part of the vapor-gas mixture removed from the evaporator with a temperature of 100 ° C, and cooled to 800 ° C. Flue gases with a temperature of 800 ° C are fed to an evaporator, in which a foam layer and a settling zone are formed by direct contact with the wastewater. Wastewater containing volatile organic substances is fed directly into the foam layer, in which most of the supplied wastewater is evaporated through direct heat exchange with high-temperature flue gases. The flow rate of wastewater containing neutralizing additive (alkali) is established by maintaining the pH 8 medium in the settling zone. The vat residue from the settling zone of the evaporator is continuously removed and sent to the furnace for incineration. The vapor – gas mixture formed in the foam layer with a temperature of 100 ° С after separation of the liquid phase (droplets) in the droplet separator is directed to the afterburner. The liquid phase from the droplet separator through the return device is fed into the settling zone of the evaporator. The afterburning is carried out in a swirling gas stream created by the vapor-gas mixture at a temperature with a periodic change in the direction of its movement. on the opposite with simultaneous heat recovery

waste and their gases by means of alternate heat exchange of the gas piston: / through the earth nozzles with the gases leaving after dokhmagani and the vapor-gas mixture fed to the afterburner. The temperature condition in the afterburner is restrained by burning fuel. Waste gases from the afterburner contain organic and organochlorine compounds in amounts less than 20 mg / m, chlorine in the form of chlorine-hydrogen, less than 50 mg / m, carbon monoxide less than 15G mg / m, dust - less than 100 mg / m. After the afterburning, the flue gases are removed to the atmosphere.

Example 2. The process conditions are similar to those indicated in example 1, only the tag is different ;, in the settling zone of the mate, the medium is maintained at a pH of 10. Leaving the flue gas after the afterburner

The logic specified in example 1.

Example 3. The process conditions are similar to those specified in Example 1, characterized in that the pH of the bottoms residue is maintained at 9. The composition of the smoke gases after the afterburner is similar to that indicated in Example 1.

Example 4. The process conditions are similar to those indicated in example 1, characterized in that the pH of the bottom of the bottom tank in the settling zone is maintained at 5. In the flue gases after the afterburning, the chlorine content in the form of hydrogen chloride is about 200 mg / m, oxide carbon 250 mg / m; organic and chlorine organic compounds less than 20 mg / m; dust less than 100 mg / m.

Example 5. The process conditions are similar to those indicated in example 1, characterized in that the pH of the bottoms residue is maintained at 12. The composition of the flue gases is similar to that indicated in example 1. The consumption of neutralizing additive increases as compared with example 1.

Example 6. The process conditions are similar to those indicated in Example 5, characterized in that the waste water containing fraction is fed into the settling zone of the evaporator. After the after-burning, flue gases contain organic and organochlorine compounds in an amount of less than 20 mg / m, hydrogen chloride 90 mg / m, carbon monoxide 200 mg / m, dust - less than 100 mg / m.

Example 7 The conditions for conducting the process are similar to those indicated in example 2, characterized in that the neutralizing additive is introduced into the foam layer of the evaporator in a separate stream in the form of a 10% alkali solution. The composition of the flue gases after the burnout is similar to that specified in Example 1.

Example B. The process conditions are similar to those indicated in Example 2, characterized in that the waste fed to 5 incineration contains 2% fluorine, sulfur and phosphorus in the form of fluorine, sulfur and phosphoropic acid compounds. After the afterburning in the flue gases, the content of carbon monoxide is less than 150 mg / m, organic sulfur and phosphorus compounds are less than 50 mg / m, hydrogen fluoride is less than 5 mg / m, phosphorus in terms of PzOs is less than 50 mg / m, oxides sulfur in terms of SO - less than 60 mg / m, dust - 5 less than 100 mg / m.

EXAMPLE 9 The conditions of the process are similar to those indicated in Example 2, characterized in that the waste supplied from the incineration contains fluorine, sulfur, phosphorus up to 2% in its composition, and the neutralizing additive in the form of vodka. Suspensions Calcium hydroxide with a concentration of 20 g / l serves 8 layers of evaporator. The composition of the flue gases is similar to that specified in example 8.

Example 10 The process conditions are similar to those indicated in Example 9. They are different in that the liquid phase from the droplet separator is directed to the area of the frothy evaporator. In flue gases, the after-burning dust content is more than 150 mg / m.

The implementation of the method allows for the effective disposal of waste containing chlorine, fluorine, sulfur and phosphorus compounds.

Claims (1)

Invention Formula The method of thermal neutralization of waste of various aggregates according to ed. St. 1015189, characterized in that, in order to increase the effectiveness of the disposal of waste containing chlorine, fluorine, sulfur, phosphorus compounds, evaporation of the water-cut liquid waste is carried out by bubbling fuel and waste products through them with the formation of a foam layer and settling zones, liquid watered waste and a neutralizing additive are supplied to the foam layer in an amount necessary to maintain a pH of 8-10 in the settling zone, and the bottoms are removed from the settling zone, and the resulting vapor-gas mixture is separated fly ash and send it to the settling zone, and the gas-vapor mixture is burned when the gas flow direction changes periodically to the opposite, and the heat recovery is carried out by alternately contacting the gas-permeable heat-accumulating nozzle with the gases coming from the afterburning and supplying the gas-vapor mixture to the afterburning . Shd JTb p uP  SHf  Shfiitre TopmZo bWoSbie gases