FI105655B - Outwardly open system and process for removing odorous gases occurring in the breakdown of bio-waste, thereby preventing the chemicals evaporating into the ambient air - Google Patents

Abstract

The invention, "Outwardly open system and process for removing odorous gases occurring in the breakdown of bio- waste, thereby preventing the chemicals evaporating into the ambient air" relates to the removal of nitrogenous and sulphurous compounds in bio-waste from odorous air. A binding solution for odour compounds flows in a pump- circulated cycle 3 of an absorption reactor 7, the binding solution is brought into counter-current contact with an odorous air flow, evaporation being prevented due to the fact that the odorous air flow saturated to 100 percent relative humidity is fed into the reactor. At the top, the absorption reactor 7 has an outlet pipe 8, which leads to the ambient air, and below this is a sprinkler 9 for the binding solution 19, the sprinkler forms the binding solution 19 into droplets that land as an even rain over the cross-sectional area of the entire absorption reactor 7, the binding solution 19 falls on to a porous layer 10, so that under gravity it flows through the cells 10, a saturated moist, odorous air flow rises up towards the flow of binding solution 19, the odorous air flow comes into contact with the binding solution 19 in the porous cell structure 10, nitrogenous and sulphurous odour compounds bond chemically with the binding solution 19 that flows to the circulation vessel 11, when the binding solution 19 is saturated, a solenoid discharge valve in the circulation vessel 11 opens, controlled by a contents sensor 12 and the circulation vessel 11 is discharged into a drainage pipe, a storage reservoir being filled with fresh, active binding solution 19 by means of a top-up pump 14. <IMAGE>

Description

-1- 105655 "An open-air system and method for removing odor gases resulting from the decomposition of organic wastes by preventing the evaporation of chemicals into the open air".

* 5 The scope of the invention encompasses all such objects in which nitrogen and sulfur containing odor compounds flow under ambient atmospheric pressure and cause significant odor problems. Such objects include e.g. pumping stations for wastewater networks, wastewater treatment plants, biowaste composting plants, slaughterhouse waste treatment plants, pigs, industrial wastewater treatment plants and 10 air-conditioning sewage systems. All these sites are characterized by odors formed as a result of decomposition processes of organic waste. Areas where, for example, pure hydrocarbons are volatile because they do not contain sulfur or nitrogen atoms are not covered by the process.

The invention is based on a known chemical property and a combination of known chemical properties of the Kemi-15 apparatus.

The present invention is neither an improvement nor a modification of any existing device or method. Existing deodorization methods can be grouped into three types. First, there are different filters. Activated carbon and peat, for example, act as filters. These methods provide only a partial reduction in the odor intensity. Odor gases are usually extremely complex chemical gas mixtures. The most sensitive gas chromatographic separation and analysis equipment can detect hundreds of different molecules from gas mixtures caused by bacterial decomposition. Naturally, each molecule has its own properties with respect to the surfaces of other materials, and there is no such surface absorption material that reacts, i.e. binds all foreign molecules from the air. Naturally, the filters also cause a significant flow resistance to the duct system, which means that they cannot be used without other technical support (eg fans).

They form another group. methods for chemically transforming odor compounds into a less odorous form. Typical reagents include various oxidants. Both oxygen and ozone are used for this purpose. The result is the same as with filters. Some compounds oxidize, others do not, and the result is only a partial reduction in odor intensity.

The third widely used odor control method is based on 35 masking of air. This method is, of course, highly questionable, since it only seeks to deceive the human nose by masking the actual harmful stench with a strong perfume.

The present process differs from the others in that it completely eliminates the odors caused by the decomposition of organic materials. As a measure of deodorization, the human nose is the only odor indicator available. There are many types of electronic sensors, but their utility is best served by guarding one or more specified gas components. The present invention utilizes the known chemical property of providing an aqueous phase reaction which specifically reacts, i.e., binds in gaseous form compounds containing a sulfur or a nitrogen atom as part of the molecule. Since compounds in odor gas mixtures generally contain either 100% or close to nitrogen or sulfur, their removal from the air is perceived as complete removal of odors.

50

All wastewater pumping stations, wastewater treatment plants, biowaste composting plants, slaughterhouse waste treatment plants, canteens, industrial wastewater treatment plants, and air conditioning system ductwork shall have ventilation pipes and drainage ducts to ensure that the system is properly operated.

All of these ventilation ducts as well as the exhaust air outlet vents are open to the open air.

A very well-known and "afflicted" problem arises from the fact that these ventilation ducts and exhaust air outlet vents impart bad odors to their environment, which cause problems, including housing comfort.

i - -3 - 105655

The removal of the odorous gas compounds from the air stream takes place in a special absorption reactor. The purpose of this reactor is to contact the binder solution with the odorous air stream 65 with a large contact area and sufficient contact time. The flows in the reactor are upstream, whereby the evaporation in the reactor is carried along with the flow to the outside air. When the contact surface is large, the evaporation potential, i.e. chemical loss, is also high. To prevent this, the reactor is supplied with a 70 stinking air stream saturated with 100% relative humidity, which prevents evaporation and hence chemical losses into the open air and minimizes system operating costs. The scent-free air flows into the open air.

When the air flow from the odor source (1) outwards, the circulation pump (2) is started 75 by the flow switch (17) in the outlet pipe (8). At that time, the perfume binding agent solution flows in the in-process circuit (3). Simultaneously with the start of the circulation pump (2), the solenoid valve (4) of the cold water pipe (16) connected to the public water supply network (15) opens, thereby humidifying the incoming streams of air in the humidifying cell (5). The humidifier 80 operates as a conventional cellular humidifier (5) commonly used in air conditioning and is sized according to the incoming odor air flow. The part of the pipe (6) after the humidifier (5) before the absorption reactor (7) has a relative humidity of 100% RH of the incoming air.

The absorption reactor (7) has an outlet outlet (8) at the top to the open air, below it 85 is a binder solution (T9J spreader (9) which drops the binding solution (19) across the entire absorption surface of the absorption reactor (7). that there is no malicious jet effect (not a nozzle requiring flow pressure) as the air flow resistance must be low to allow air flow under external atmospheric pressure.

• 90 The scent gas binder solution (19) is deposited by gravity on a highly porous layer (10). The porous layer (10) is one which has a very low flow resistance at very low flow rates (<0.5m / s). Furthermore, the porous layer (10) is of such a structure that it has a very large surface area in relation to its volume (> 1000m 2 / 1m 3). Porous porous. -4- 105655 95 cellular structures known per se (10), which have to withstand the effects of water and chemicals.

As the binding solution (19) settles on the porous honeycomb structure (10), it begins to flow through the honeycomb (10) by gravity. Against the flow of the binder solution (19) in the absorption reactor (7), a moist saturated, stinky air stream 100, which contacts the binder solution (19) in the porous lubricant structure (10), rises. The thickness of the cellular structure (10) is dimensioned such that the desired chemical reactions take time to take place. The nitrogen and sulfur-containing odor compounds are chemically bound to a binding solution (19) flowing from the lower part of the absorption reactor (7) to the recirculation tank (11). From the circulation tank (11), the binding solution 105 parts (19) is fed to the circulation pump (2).

The concentration sensor (12) measures the activity of the binding solution (19). When the binding solution (19) is saturated, i.e., when the reagents are exhausted, according to the control signal from the concentration sensor (12), the drain solenoid valve (13) of the circulation tank (11) and the filling pump (14) of the storage tank (18) are opened. In this case, according to the control signal provided by the volume sensor (12), the circulation tank (11) is emptied of saturated binding solution (19) to the general drain (20) and filled with new active binding solution (19) from the storage tank (18). After draining and refilling, the circulation pump starts (2).

The binder solution (19) is a solution that is fully suitable for the environment and drainage in the general sewerage network and in landfills.

1. An open-air system for removing odor gases resulting from the decomposition of organic wastes by preventing the evaporation of chemicals into the open air, comprising an in-process recirculation circuit (3) with a flowable (5) effluent (5) ), an absorber (9) of an absorption reactor (7) having an outflow outlet (125) leading up to the open air, below which the scavenger (19) of the scavenger gas scavenger (19) settles under the influence of gravity of the 105655, as well as the lowest purifying odor gas inlet tube (6), after the binder solution (19) settles on the honeycomb structure (10), it starts to flow through gravity under gravity, against the backdrop of the binder solution (19) in the absorption reactor (7) stinking air flow in contact with the binder solution (19) in the honeycomb structure (10), nitrogen and sulfur-containing odor compounds chemically bond to the binding solution (19) flowing from the lower part of the absorption reactor (7) to the circulation tank (11), from the circulation tank (11) to the circulation pump (2), the concentration sensor (12) measures the activity of the ), i.e. when the reagents are exhausted, according to the control signal provided by the concentration sensor (12), the emptying solenoid valve (13) of the circulation tank (11) and the filling pump (14) of the storage tank (18) are opened. drains from saturated binder solution 140 (19) to the general drain (20) and is filled with new active binder solution (19) from storage tank (18), characterized in that the odorous air (6) entering the absorption reactor (7) is wetted with 100% RH prior to contacting it with the binding solution (3) in the honeycomb structure (10) such that 145 whereby evaporation at varying temperatures causes chemical loss, and wherein in the absorption reactor (7), the pressure loss of the flow of odorous air (6) at low flow rates is less than the gravitational force caused by the temperature difference between the odorous air (6) and the outdoor air.

System according to Claim 1, characterized in that a solution of organic chemicals and water which is sensitized with compounds containing nitrogen and sulfur atoms is used as the scent gas scavenger solution (19).

155 3. A system as claimed in claim 1, characterized in that such a heater is used to moisten the incoming odorous air (6). -β- humidifier (5), which humidifies the incoming fumed air (6) with 100% RH of the incoming air (6) with cold tap water.

A system according to claim 1, characterized in that the binder solution dispenser (9) is of such a structure that drops the binder solution (19) into a uniform rain across the cross-section of the absorption reactor (7) and is also such that it does not flow 165 pressure nozzle).

System according to Claim 1, characterized in that the porous layer (10) is dimensioned to have a very low flow resistance at low flow rates and is designed to have a very large surface area in relation to its volume, in addition to the thickness of the honeycomb structure (10). is dimensioned so that the desired chemical reactions are given sufficient time to occur.

A method for removing odorous gaseous 175 from organic waste decomposition in the presence of external air pressure and open to the atmosphere by preventing the evaporation of chemicals into the open air, comprising an in-process circulator (3) with an incineration solution (19) (5), an absorber (9) of an absorption reactor (7) having an outlet outlet (8) uppermost to the open air, below which a scavenger (180) of the scavenger gas scavenger (19) descends on the bed (10) by gravity and (6), after the binder solution (19) settles on the honeycomb structure (10), it starts to flow through the honeycomb (10) by gravity, the absorbent reactor (7) rises against the flow of the binder solution (19) and contacts the binding solution (19). with kennostora structure (10), nitrogen and sulfur containing odor compounds p chemically immersed in the binding solution (19) flowing from the lower part of the absorption reactor (7) to the circulation tank (11), from the circulation tank (11) the binding solution (19) is fed to the circulation pump (2), the concentration sensor (12) measures activity of the binding solution (19). -7- 105655 190 (19), when the reagents are exhausted, i.e., the control signal from the concentration sensor (12) opens the emptying solenoid valve (13) of the circulation tank (11) and the filling pump (14) of the storage tank (18). 12), the circulating tank (11) is emptied of saturated binding solution (19) to the general sewer (20) and 195 filled with a new active binding solution (19) from the storage tank (18), characterized in that the smell gas containing air enters the absorption reactor (7). 100% RH to relative humidity prior to contact with the binder solution (3) in the honeycomb structure (10) such that 200 volatiles at varying temperatures due to the openness of the process do not cause chemical loss, and in the absorber reactor (7) smaller than those of odoriferous air (6 ) and the weight lifting force caused by the temperature difference between the outdoor air and the outside air.

205 7. A method according to claim 6, characterized in that a solution of organic chemicals and water which is sensitized with compounds containing nitrogen and sulfur atoms is used as the scent gas binding solution (19).

8. A method according to claim 6, characterized in that a humidifier (5) is used to moisten the incoming odorous air (6) with a humidity of 100% RH relative to the incoming odorous gas (6) with cold tap water.

Method according to claim 6, characterized in that the binder solution spreader (9) is of such a structure that drops the binding solution (19) into a uniform rain across the cross-section of the absorption reactor (7) and is also non-pressurized (no flow). pressure nozzle).

220 105655. The method according to claim 6, characterized in that the porous layer (10) is dimensioned to have a very low flow resistance at low flow rates and is designed to have a very large surface area in relation to its volume, in addition to the honeycomb structure (10). ) The thickness of 225 is dimensioned so that the desired chemical reactions are given sufficient time to occur.

m

Claims (10)

1. Dense open system for the removal of odorous gases which have arisen in the degradation of biogenic waste, so that the evaporation of the chemicals into the outside air has been prevented, comprising an internal circulation circuit (3) for a process in which a circulation solution (19) for a circulation circuit odor compounds flow, a humidification cell (5) for an incoming odor stream (6), an absorption reactor (7) with an outlet tube (8) leading to the outdoor air at the top, below which a spacer (9) for the bonding solution (19), the bond solution (19) for odor gas settles on a layer (10) as a result of gravity and underneath an inlet tube (6) for the odor gas to be purified, after the bond solution (19) settles on the cell structure (10), flowing through the cells (10) as a result of gravity, a smelling air stream rises in the absorption reactor (7) up to the flow of bonding solution (19), which smells air stream into contact with the The inflammation solution (19) in the cell structure (10), nitrogen and sulfur-containing odorants chemically bind to the bonding solution (19) which flows from the lower part of the absorption reactor (7) to a circulation vessel (11), from the circulation vessel (11). the bonding solution (19) to a circulation pump (2), a holding sensor (12) measures the activity of the bonding solution (19), when the bonding solution (19) is saturated, i.e. when the reagents have run out, according to a control signal given by the holding sensor (12), a discharge solenoid valve (13) is opened at the circulation container (11) and a pump (14) for filling at a reservoir container (18), whereby the circulation container (11) is emptied saturated bonding solution (19) to a general sewage line (20) according to a control signal provided by the holding sensor (12) and filled with a new active bonding solution (19) from the storage container (18), characterized in that the odorous gas (6) entering the absorption reactor (7) is humidified to 100% RH relative humidity before coming into contact with the bonding solution (3) in the cell structure (10) so that, depending on the openness of the system, the evaporation of the system does not cause any chemical loss, and in which absorption reactor (7). ) the pressure loss of the odorous air (6) flow at low flow rates is less compared to the self-drag lift force caused by temperature the difference between the odor gas-containing air (SJöch outdoor air). System according to claim 1, characterized in that such a solution of organic chemicals and water is used as a bonding solution (19) for odorous gases which have been sensitized to react with articles containing nitrogen and sulfur atoms. 10 105655 3. A system according to claim 1, characterized in that for humidifying incoming odorous gas (6), such a cell humidifier (5) is used which humidifies the incoming odorous air (6) to 100% RH relative humidity with potassium water conduit water. System according to claim 1, characterized in that the spacer (9) of the bonding solution has such a structure that it forms the bonding solution (19) into drops which settle as a uniform rain on the entire surface of the absorption reactor (7) and are furthermore so that it does not produce a pressurized shower effect (not a nozzle that requires flow pressure). System according to claim 1, characterized in that the porous layer (10) is dimensioned to be so that its flow resistance at low flow rates is very small, and is of its structure such that it has a very large surface area. to its volume, in addition, the thickness of the cell structure (10) is sized so that the desired chemical reactions have sufficient time to occur. A method for removing odorous gases under extreme air pressure, which odorous gases have formed upon the degradation of biogenic waste, and are openly leaking so that the evaporation of the chemicals into the outdoor air, including an internal circulation circuit (3), for a process in which a circulation circuit is a binding solution (19) for odor compounds flows, a humidification cell (5) for an incoming odor stream (6), an absorption reactor (7) with an outlet tube (8) leading to the outdoor air at the top, below which a spacer (9) for the bonding solution ( 19), wherein the odor gas bonding solution (19) settles on a layer (10) as a result of gravity and below an inlet tube (6) for the odor gas to be purified after the bonding solution (19) settles on the cell structure (10). , it begins to flow through the cells (10) as a result of gravity, a smelling air stream in the absorption reactor (7) rising up to the flow of binding solution (19), which Odorous stream of air contacts the bonding solution (19) of the cell structure (10), nitrogen and sulfur-containing odorants chemically bind to the bonding solution (19) which flows from the lower part of the absorption reactor (7) to a circulation vessel (11), from the circulation vessel (11). ) the bonding solution (19) is led to a circulation pump (2), a content sensor (12) measures the activity of the bonding solution (19), when the bonding solution (19) is saturated, i.e. when the reagents have run out, according to a control signal given by the holding sensor (12), an emptying solenoid valve (13) is opened at the circulation container (11) and a pump (14) for filling in 105655 π at a supply container (18), then emptied the circulation vessel (11) on saturated bonding solution (19) into a general sewer line (20) according to a control signal given by the content sensor (12) and filled with a new active bonding solution ( 19) from the reservoir container (18), characterized in that the odorous air (6) entering the absorption reactor (7) is humidified to 100% RH relative humidity before coming into contact with the bonding solution (3) in the cell structure (10). that the evaporation dependent on the system and at varying temperatures of evaporation does not cause any chemical loss, and in which absorption reactor (7) the pressure loss of the odorous air (6) flow at low flow rates is less than the draft lift force caused by the temperature difference between the odorous gas (6) and the outdoor air. Process according to claim 6, characterized in that such a solution of organic chemicals and water is used as a bonding solution (19) for odorous gases which have been sensitized to react with compounds containing nitrogen and sulfur atoms. Method according to claim 6, characterized in that for humidifying incoming odorous air (6), such a cell humidifier (5) is used which humidifies the incoming odorous air (6) with 100% RH relative humidity with potassium water conduit water. 9. A method according to claim 6, characterized in that the spreader (9) of the bonding solution has such a structure that it forms the bonding solution (19) for drops which settle as a uniform rain on the entire surface of the absorption reactor (7) and is also such that it does not forms a pressurized shower effect (not a nozzle that requires flow pressure). 9 105655 System according to claim 6, characterized in that the porous layer (10) is dimensioned to be such that its flow resistance at low flow rates is very small, and is of its structure such that it has a very large surface area. in addition to its volume, in addition, the thickness of the cell structure (10) is sized so that the desired chemical reactions take sufficient time to occur.