Ruks Engineering Ltd. Products and Services

IAQ Applications | CT Water Treatment | Odor & Toxic Gas Removal
Process Controllers | Calibration Gases

Odor & Toxic Gas Removal

Sewage Vent Gas Treatment
Hospital Air Treatment
Industrial Air Treatment
Pilot Plants

TREATMENT OF VENT GAS FROM SETTLING TANK OF SEWAGE TREATMENT PLANTS OR LIFT STATIONS

Treatment of sewage vent gas requires use of settlement tanks, to achieve separation of sediments from total flow, and allow recovered water to over flow for further treatment. Natural decomposition and process of putrefaction that occurs continuously to the organic matter in sewage, releases several organic gases, but mainly hydrogen sulfide (H2S), methane (CH4) and ammonia (NH3). These are highly malodorous and diffuse readily and quickly into large volume of space, if released. This offensive odor is carried by drift and wind, and can reach locations at considerable distance form its source. Change of wind direction, changes in sub soil water table level, high ambient temperature, and such other external factors impact the generation and propagation of the odor.

In addition to the generation of odorous gases, microbiology involved in the natural process of decomposition generates and supports numerous bacteria and pathogens. These bacteria and viruses are carried in the vent gas. Not all these bacteria are harmful; in fact some of them perform useful functions, and are necessary. Many STP encourage culture growth by addition of external additives and supplements. The concern of the Public Health Departments is the part of the offensive, disease and allergy causing pathogens that do exist and flourish with other beneficial pathogens. These groups of bacteria impose serious air quality problems and health hazards to the populace in the neighborhood.

It is important that vent gas from these plants do not pollute the environment with foul odors, volatile organic gases (VOC) and bacteria. The most desired result to be achieved is near zero odor level, near zero air borne bacteria and or viruses, and near zero VOC.

Many different methods are available and have been attempted with aim to achieve this. They range from simple to complex solutions, producing varying results. Some of these are; Locating the STP far away from cities, aeration of the tanks with aim to oxidize odors, chemical filters to adsorb polluting gases, wet or dry scrubbers, and masking the odors. Most of these solutions call for high operating costs, some with fair amount of capital cost as well. Though some of these solutions, either singularly or in combination with multiple treatments, have resulted in reduction of odors, none has succeeded in near total elimination of odors, BOD and COD.

Ruks Engineering presents their solution with ozone injection technology. Of all the methods attempted, this method offers the most effective solution resulting in near total elimination of odors, VOC, bacteria and viruses. There is capital cost to reckon with. Reduction achieved in operating costs, near non odorous environment, flexibility to locate plant in areas close to high human population, improvements achieved in air quality, reduced sickness due to removal of bacteria and viruses, reduction in public health expenses, and benefit to environment offset the capital cost in a very short time. Even if non tangible benefits are not considered, as it is difficult to compute them, tangible cost savings provide a fairly quick return on investment, and is sufficient to justify this system. This statement is made on the premise that the comparison is made with systems employing chemical filtration. If rerun on investment analysis for your specific application is desired, we are glad to be of service.

OZONE IN TREATMENT OF VENT GAS IN SEWAGE TREATMENT PLANTS OR LIFT STATIONS
Ozone is 3 atom molecule of oxygen with insufficient bonds, given by the chemical formula O3. It is an unstable gas, colorless, and odorless at low concentration, and at high concentration, has a characteristic smell. Its molecular weight is 48.0, has gas density of 2.144 Gms/Liter at 0EC and at atmospheric pressure, and boiling point of -112EC at atmospheric pressure. It is about 1.5 times heavier than air. Ozone is a powerful oxidizing agent. Its oxidation potential is 2.07 Volts. It has over 52% greater oxidation potential than chlorine (oxidation potential 1.35 Volts). Chlorine, either directly or in one of its many derived chemicals, is a commonly used industrial and commercial disinfectant.

Ozone has few unique properties, seldom encountered in other elements, and these properties render it the great versatility it offers for treatment of air and water. It can readily replace any chemical used to disinfect vent gas, and replace use of carbon or chemical filters. These characteristics are;

Ozone is one of the strongest known oxidants. All vapors from sewer water, odorous or not, are organic in nature. These are readily oxidized by ozone to revert the polluting gases to their natural origins such as O2, H2O and O2. In treatment of sewer vent gas, ozone concentration dosage used is high, unlike in regular indoor air quality applications. This, combined with adequate contact time, ensures removal of all gases, odors, bacteria and other chemical contaminants in vent gases.
Ozone is an excellent disinfectant. It can near totally eliminate all bacteria, viruses, algae and other micro organisms very effectively. It is not a pesticide, for it does not kill the pathogen the way pesticides perform. Instead, it has direct lysing to the cellular walls of the pathogens and causes it to rupture. It readily oxidizes the organic material in the cell structure and cell wall of the pathogen. It interferes and eventually stops the process of osmosis necessary for pathogens to sustain. It stops the cell multiplication process, and eventually leads to total destruction of the pathogens. The rapidity and effectiveness with which this process occurs is function of concentration of ozone in air and contact time between ozonized vent gas and pathogens. If applied effectively, ozone treatment of vent gas can result in total elimination of all air borne pathogens including viruses.

Streptococcus fecalis and Escherichia coil, 2 well known water borne viruses are inactivated in less than 15 seconds at ozone concentration of 0.1 mg/L. By comparison, chlorine would require about 5 times higher concentration and 10 times increase in time to achieve the same result.
Ozone has short half life. If not consumed in few minutes, it reverts to diatomic oxygen. This is, at least partially, a self limiting device preventing build up of ozone concentration in the gas vented to environment.
As ozone molecules rejoin to form oxygen, and as there are no chemicals used in the treatment, vented air from ozone treated systems do not add chemicals to the environment.

There are many different methods of ozone application in vent gas treatment, depending on the quality of vent gas expected after the treatment, and capital and operating costs of the system. Some of these employ multiple methods. Some of the commonly used methods are;

Ozone as stand alone treatment.
Ozone application, followed by carbon and or chemical filters.
Ozone application, followed by wet scrubber.
Ozone application, followed by carbon or chemical filters, and wet scrubber.
Transfer of ozone may be done directly from gas phase to gas phase, that is direct transfer of gaseous ozone to gaseous vent gas.
Transfer of ozone in aqueous phase to vent gas in gaseous phase (with use of wet scrubber).

Results of these systems are varied, and so is the capital and operating costs. For a reasonable trade off between costs, system performance, and reliability of operation, use of ozone as stand alone is adequate for most applications. If results to higher degree is desired, supplementary treatments may be considered, but this adds to the cost.

PLANT CAPACITY AND SYSTEM DESCRIPTION
Plant capacity and sizing varies and is custom sized for each application. Plant capacity is dependent on many variables such as ozone concentration, injection method, size of contact chamber, use of other odor abating devices, ambient temperature, and relative humidity.

In general Ruks Effluent Gas Treatment System comprises Ozone generator trains to produce ozone, using dry air or oxygen as feed gas. Air or Oxygen preparation packages provide the required feed gas. This package includes pre and after filters to remove particulate, refrigerant dryer to remove air borne moisture to dew point temperature (DPT) of 30EF (optional but essential in high ambient and humidity environment), and a twin tower pressure swing desiccant dryer to dry the air down to Dew Point temperature of -70EC at 100 psig, equivalent to DP temperature of -96EC at atmospheric pressure. Each train is provided with a high Dew Point temperature monitor and high DP cutout device, to trip the ozone generator system, if DP is not to the required extent. This is a safety device, and this adds to the cost, but it increases operational reliability and safety (optional). If oxygen is used as feed gas, an oxygen concentrator is added to provide oxygen on a continuous basis at oxygen concentration of 90%. Ozone concentration is 6 to 8% wt/wt if oxygen is used as feed gas, and is 1.8 to 2% wt/wt if dry air is used as feed gas.

Effluent or Vent gas from all settlement tanks, (or from lift station vent) and ozone are combined in a diffusion chamber. This is designed with high turbidity to ensure good mixing between injected ozone and vent gas. Combined vent gas and ozonized air is taken through a duct to enter into a contact chamber. Length of this duct should confirm to the aspect ratio L/D (Length/Equivalent diameter), to ensure good mixing between the treated gas and ozonized air.

The function of contact chamber is to allow sufficient contact time between vent gas and ozone to allow ozone to oxidize the polluting and odorous gases, and to effectively destroy air borne bacteria and viruses. The contact chamber performs extremely important function in achieving above objectives. The contact chamber is provided with multiple number of passes, to ensure effective contact between ozone and the polluting gas to promote oxidization. The contact chamber may be constructed in situ by the building contractor on large projects, or may be provided by Ruks Engineering.

Effectiveness of odor, VOC and bacteria removal, or rather the entire success of such projects depend on;

The quantity of ozone used.
Concentration of ozone.
Diffusion of ozone and effective mixing.
Sufficient contact time.

Vent gas and ozonized air mixture exiting from the contact chamber will be free of odors and pollutants, and is now ready for discharge to the environment. It is highly recommended to use a stack and discharge the vented gas, as high as possible. Passage of vent gas through the stack also provides additional contact time for oxidation, but this is not the main purpose of the stack.

CONTROLS SYSTEM
VOC Sensor or ORP probe/monitor and controller and ozone analyzer are installed in the air exiting from the stack. The Sensor Controller senses the VOC in the vent discharge air and modulates production of ozone by the generators proportionally. Ozone analyzer tracks residual ozone concentration in vent discharge air and reduces ozone production proportionally. The generator is modulated from signals from both these. OSHA (Occupational Safety and Health Administration, USA) stipulates ozone level shall not exceed 0.1 PPM (100 PPB) in discharge air to environment. Ozone analyzer assists in ensuring compliance to this, and provides alarm in the event of exceedence.

The entire system is operated by our patented microprocessor controller, which regulates the output of ozone in relation to reading of VOC or ORP and ozone analyzer. This can communicate to facility operator's BMS system. If this is remote or unmanned site, it is possible to extend it for communicating to remote location. Some additional equipment may be needed to achieve this, extent of which depends on the extent of automation desired.

Other safety features include secondary high ozone concentration monitor in the vent gas exhaust prior to discharge, high concentration ozone in air analyzer on ozone generator, and low concentration ozone in air analyzer for plant room, besides all other normally provided safety features.

FOR FURTHER DETAILS AND NO OBLIGATION QUOTATION FOR YOUR SPECIFIC SYSTEM, PLEASE CONTACT RUKS ENGINEERING OR OUR AUTHORIZED DISTRIBUTORS

TREATMENT OF EXHAUST AIR FROM HOSPITALS AND LABORATORIES

Some of the Activities performed in hospitals require the room air be discharged to the environment. Air conditioning systems for facilities such as operation theaters, pre and post surgical wards, mortuary, and some laboratories are designed to operate on 100% outdoor air and the entire room air is exhausted. This air stream contains toxic chemicals, VOC, is malodorous, and may contain air borne pathogens. This air stream diffuses readily and quickly into large volume of space upon release and is carried by drift and wind, and can reach locations at considerable distance form its source. Change of wind direction, changes in sub soil water table level, high ambient temperature, and such other external factors impact the generation and propagation of the odor. It is not uncommon is some hospital installations to locate supply air intake system not far from the exhaust air and this promotes recirculation of contaminated exhaust air back to the air conditioning plant. This is of concern to the Public Health Departments and HVAC design engineers. The odor and bacteria released impose serious air quality problems and health hazards to the populace in the neighborhood.

It is important that vent gas from these plants do not pollute the environment with foul odors, volatile organic gases (VOC) and bacteria. The most desired result to be achieved is near zero odor level, near zero air borne bacteria and or viruses, and near zero VOC.

Many different methods are available and have been attempted with aim to achieve this. They range from simple to complex solutions, producing varying results. Some of these are; Locating the exhaust vent as far high as possible with the hope it is diffused into the environment, chemical filters to adsorb polluting gases, wet or dry scrubbers, and masking the odors. Most of these solutions call for high operating costs, some with fair amount of capital cost as well. Though some of these solutions, either singularly or in combination with multiple treatments, have resulted in reduction of odors, none has succeeded in near total elimination of odors, VOC, and bacteria.

Ruks Engineering presents their solution with ozone injection technology. Of all the methods attempted, this method offers the most effective solution resulting in near total elimination of odors, VOC, bacteria and viruses. There is capital cost to reckon with. Reduction achieved in operating costs, near non odorous environment, flexibility to locate plant in areas close to high human population, improvements achieved in air quality, reduced sickness due to removal of bacteria and viruses, reduction in public health expenses, and benefit to environment offset the capital cost in a very short time. Even if non tangible benefits are not considered, as it is difficult to compute them, tangible cost savings provide a fairly quick return on investment, and is sufficient to justify this system. This statement is made on the premise that the comparison is made with systems employing chemical filtration. If rerun on investment analysis for your specific application is desired, we are glad to be of service.

OZONE IN TREATMENT OF EXHAUST AIR IN HEALTH CARE FACILITIES
Ozone is 3 atom molecule of oxygen with insufficient bonds, given by the chemical formula O3. It is an unstable gas, colorless, and odorless at low concentration, and at high concentration, has a characteristic smell. Its molecular weight is 48.0, has gas density of 2.144 Gms/Liter at 0EC and at atmospheric pressure, and boiling point of -112EC at atmospheric pressure. It is about 1.5 times heavier than air. Ozone is a powerful oxidizing agent. Its oxidation potential is 2.07 Volts. It has over 52% greater oxidation potential than chlorine (oxidation potential 1.35 Volts). Chlorine, either directly or in one of its many derived chemicals, is a commonly used industrial and commercial disinfectant.

Ozone has few unique properties, seldom encountered in other elements, and these properties render it the great versatility it offers for treatment of air and water. It can readily replace any chemical used to disinfect vent gas, and replace use of carbon or chemical filters. These characteristics are;

Ozone is one of the strongest known oxidants. All vapors from sewer water, odorous or not, are organic in nature. These are readily oxidized by ozone to revert the polluting gases to their natural origins such as O2, H2O and O2. In treatment of sewer vent gas, ozone concentration dosage used is high, unlike in regular indoor air quality applications. This, combined with adequate contact time, ensures removal of all gases, odors, bacteria and other chemical contaminants in vent gases.
Ozone is an excellent disinfectant. It can near totally eliminate all bacteria, viruses, algae and other micro organisms very effectively. It is not a pesticide, for it does not kill the pathogen the way pesticides perform. Instead, it has direct lysing to the cellular walls of the pathogens and causes it to rupture. It readily oxidizes the organic material in the cell structure and cell wall of the pathogen. It interferes and eventually stops the process of osmosis necessary for pathogens to sustain. It stops the cell multiplication process, and eventually leads to total destruction of the pathogens. The rapidity and effectiveness with which this process occurs is function of concentration of ozone in air and contact time between ozonized vent gas and pathogens. If applied effectively, ozone treatment of vent gas can result in total elimination of all air borne pathogens including viruses.

Streptococcus fecalis and Escherichia coil, 2 well known water borne viruses are inactivated in less than 15 seconds at ozone concentration of 0.1 mg/L. By comparison, chlorine would require about 5 times higher concentration and 10 times increase in time to achieve the same result.
Ozone has short half life. If not consumed in few minutes, it reverts to diatomic oxygen. This is, at least partially, a self limiting device preventing build up of ozone concentration in the gas vented to environment.
As ozone molecules rejoin to form oxygen, and as there are no chemicals used in the treatment, vented air from ozone treated systems do not add chemicals to the environment.

Ozone as stand alone treatment.
Ozone application, followed by carbon and or chemical filters.
Ozone application, followed by wet scrubber.
Ozone application, followed by carbon or chemical filters, and wet scrubber.
Transfer of ozone may be done directly from gas phase to gas phase, that is direct transfer of gaseous ozone to gaseous vent gas.
Transfer of ozone in aqueous phase to vent gas in gaseous phase (with use of wet scrubber).

Results of these systems are varied, and so is the capital and operating costs. For a reasonable trade off between costs, system performance, and reliability of operation, use of ozone as stand alone is adequate for most applications. If results to higher degree is desired, supplementary treatments may be considered, but this adds to the cost.

PLANT CAPACITY AND SYSTEM DESCRIPTION
Plant capacity and sizing varies and is custom sized for each application. Plant capacity is dependent on many variables such as ozone concentration, injection method, size of contact chamber, use of other odor abating devices, ambient temperature, and relative humidity.

In general, Ruks Effluent Gas Treatment System comprises Ozone generator trains to produce ozone, using dry air or oxygen as feed gas. Air or Oxygen preparation packages provide the required feed gas. This package includes pre and after filters to remove particulate, refrigerant dryer to remove air borne moisture to dew point temperature (DPT) of 30EF (optional but essential in high ambient and humidity environment), and a twin tower pressure swing desiccant dryer to dry the air down to Dew Point temperature of -70EC at 100 psig, equivalent to DP temperature of -96EC at atmospheric pressure. Each train is provided with a high Dew Point temperature monitor and high DP cutout device, to trip the ozone generator system, if DP is not to the required extent. This is a safety device, and this adds to the cost, but it increases operational reliability and safety (optional). If oxygen is used as feed gas, an oxygen concentrator is added to provide oxygen on a continuous basis at oxygen concentration of 90%. Ozone concentration is 6 to 8% wt/wt if oxygen is used as feed gas, and is 1.8 to 2% wt/wt if dry air is used as feed gas.

Air to be treated and ozone are combined in a diffusion chamber. This is designed with high turbidity to ensure good mixing between injected ozone and exhaust air. The combined ozonized air is taken through a duct to enter into a contact chamber. Length of this duct should confirm to the aspect ratio L/D (Length/Equivalent diameter), to ensure good mixing between the treated gas and ozonized air.

The function of contact chamber is to allow sufficient contact time between vent gas and ozone to allow ozone to oxidize the polluting and odorous gases, and to effectively destroy air borne bacteria and viruses. The contact chamber performs extremely important function in achieving above objectives. The contact chamber is provided with multiple number of passes, to ensure effective contact between ozone and the polluting gas to promote oxidization. The contact chamber may be constructed in situ by the building contractor on large projects, or may be provided by Ruks Engineering.

Effectiveness of odor, VOC and bacteria removal, or rather the entire success of such projects depend on;

The quantity of ozone used.
Concentration of ozone.
Diffusion of ozone and effective mixing.
Sufficient contact time.

Vent gas and ozonized air mixture exiting from the contact chamber will be free of odors and pollutants, and is now ready for discharge to the environment. It is highly recommended to use a stack and discharge the vented gas, as high as possible. Passage of vent gas through the stack also provides additional contact time for oxidation, but this is not the main purpose of the stack.

CONTROLS SYSTEM
VOC Sensor or ORP probe/monitor and controller and ozone analyzer are installed in the air exiting from the stack or duct. The Sensor Controller senses the VOC in the discharge air and modulates production of ozone by the generators proportionally. Ozone analyzer tracks residual ozone concentration in discharge air and reduces ozone production proportionally. The generator is modulated from signals from both these. OSHA (Occupational Safety and Health Administration, USA) stipulates ozone level shall not exceed 0.1 PPM (100 PPB) in discharge air to environment. Ozone analyzer assists in ensuring compliance to this, and provides alarm in the event of exceedence.

The entire system is operated by our patented microprocessor controller, which regulates the output of ozone in relation to reading of VOC or ORP and ozone analyzer. This can communicate to facility operator's BMS system. If this is remote or unmanned site, it is possible to extend it for communicating to remote location. Some additional equipment may be needed to achieve this, extent of which depends on the extent of automation desired.

Other safety features include secondary high ozone concentration monitor in the vented exhaust air prior to discharge, high concentration ozone in air analyzer on ozone generator, and low concentration ozone in air analyzer for plant room, besides all other normally provided safety features.

FOR FURTHER DETAILS AND NO OBLIGATION QUOTATION FOR YOUR SPECIFIC SYSTEM, PLEASE CONTACT RUKS ENGINEERING OR OUR AUTHORIZED DISTRIBUTORS

TREATMENT OF TOXIC AND ODOROUS EFFLUENT AIR FROM INDUSTRIES

Some industrial processes contaminate the room or process air with toxic gases and odor, and this requires the air be discharged to the environment. Pharmaceutical and food processing industries may also have microbial organisms and bacteria in the exhausted air. In some instances, the air conditioning systems for such facilities are designed to operate on 100% outdoor air, and the entire room air is exhausted. This air stream diffuses readily and quickly into large volume of space upon release and is carried by drift and wind, and can reach locations at considerable distance form its source. Change of wind direction, changes in sub soil water table level, high ambient temperature, and such other external factors impact the generation and propagation of the odor. It is not uncommon is some installations to locate supply air intake system not far from the exhaust air and this promotes recirculation of contaminated exhaust air back to the air conditioning plant. This is of concern to the Public Health Departments and HVAC design engineers. The odor and bacteria released impose serious air quality problems and health hazards to the populace in the neighborhood.

It is important that vent gas from these plants do not pollute the environment with foul odors, volatile organic gases (VOC) and bacteria. The most desired result to be achieved is near zero odor level, near zero air borne bacteria and or viruses, and near zero VOC.

Many different methods are available and have been attempted with aim to achieve this. They range from simple to complex solutions, producing varying results. Some of these are; Locating the exhaust vent as far high as possible with the hope it is diffused into the environment, chemical filters to adsorb polluting gases, wet or dry scrubbers, and masking the odors. Most of these solutions call for high operating costs, some with fair amount of capital cost as well. Though some of these solutions, either singularly or in combination with multiple treatments, have resulted in reduction of odors, none has succeeded in near total elimination of odors, VOC, and bacteria.

Ruks Engineering presents their solution with ozone injection technology. Of all the methods attempted, this method offers the most effective solution resulting in near total elimination of odors, VOC, bacteria and viruses. There is capital cost to reckon with. Reduction achieved in operating costs, near non odorous environment, flexibility to locate plant in areas close to high human population, improvements achieved in air quality, reduced sickness due to removal of bacteria and viruses, reduction in public health expenses, and benefit to environment offset the capital cost in a very short time. Even if non tangible benefits are not considered, as it is difficult to compute them, tangible cost savings provide a fairly quick return on investment, and is sufficient to justify this system. This statement is made on the premise that the comparison is made with systems employing chemical filtration. If rerun on investment analysis for your specific application is desired, we are glad to be of service.

OZONE IN TREATMENT OF EXHAUST AIR IN HEALTH CARE FACILITIES
Ozone is 3 atom molecule of oxygen with insufficient bonds, given by the chemical formula O3. It is an unstable gas, colorless, and odorless at low concentration, and at high concentration, has a characteristic smell. Its molecular weight is 48.0, has gas density of 2.144 Gms/Liter at 0EC and at atmospheric pressure, and boiling point of -112EC at atmospheric pressure. It is about 1.5 times heavier than air. Ozone is a powerful oxidizing agent. Its oxidation potential is 2.07 Volts. It has over 52% greater oxidation potential than chlorine (oxidation potential 1.35 Volts). Chlorine, either directly or in one of its many derived chemicals, is a commonly used industrial and commercial disinfectant.

Ozone has few unique properties, seldom encountered in other elements, and these properties render it the great versatility it offers for treatment of air and water. It can readily replace any chemical used to disinfect vent gas, and replace use of carbon or chemical filters. These characteristics are;

Ozone is one of the strongest known oxidants. All vapors from sewer water, odorous or not, are organic in nature. These are readily oxidized by ozone to revert the polluting gases to their natural origins such as O2, H2O and O2. In treatment of sewer vent gas, ozone concentration dosage used is high, unlike in regular indoor air quality applications. This, combined with adequate contact time, ensures removal of all gases, odors, bacteria and other chemical contaminants in vent gases.
Ozone is an excellent disinfectant. It can near totally eliminate all bacteria, viruses, algae and other micro organisms very effectively. It is not a pesticide, for it does not kill the pathogen the way pesticides perform. Instead, it has direct lysing to the cellular walls of the pathogens and causes it to rupture. It readily oxidizes the organic material in the cell structure and cell wall of the pathogen. It interferes and eventually stops the process of osmosis necessary for pathogens to sustain. It stops the cell multiplication process, and eventually leads to total destruction of the pathogens. The rapidity and effectiveness with which this process occurs is function of concentration of ozone in air and contact time between ozonized vent gas and pathogens. If applied effectively, ozone treatment of vent gas can result in total elimination of all air borne pathogens including viruses.

Streptococcus fecalis and Escherichia coil, 2 well known water borne viruses are inactivated in less than 15 seconds at ozone concentration of 0.1 mg/L. By comparison, chlorine would require about 5 times higher concentration and 10 times increase in time to achieve the same result.
Ozone has short half life. If not consumed in few minutes, it reverts to diatomic oxygen. This is, at least partially, a self limiting device preventing build up of ozone concentration in the gas vented to environment.
As ozone molecules rejoin to form oxygen, and as there are no chemicals used in the treatment, vented air from ozone treated systems do not add chemicals to the environment.

Ozone as stand alone treatment.
Ozone application, followed by carbon and or chemical filters.
Ozone application, followed by wet scrubber.
Ozone application, followed by carbon or chemical filters, and wet scrubber.
Transfer of ozone may be done directly from gas phase to gas phase, that is direct transfer of gaseous ozone to gaseous vent gas.
Transfer of ozone in aqueous phase to vent gas in gaseous phase (with use of wet scrubber).

Results of these systems are varied, and so is the capital and operating costs. For a reasonable trade off between costs, system performance, and reliability of operation, use of ozone as stand alone is adequate for most applications. If results to higher degree is desired, supplementary treatments may be considered, but this adds to the cost.

PLANT CAPACITY AND SYSTEM DESCRIPTION
Plant capacity and sizing varies and is custom sized for each application. Plant capacity is dependent on many variables such as ozone concentration, injection method, size of contact chamber, use of other odor abating devices, ambient temperature, and relative humidity.

In general, Ruks Effluent Gas Treatment System comprises Ozone generator trains to produce ozone, using dry air or oxygen as feed gas. Air or Oxygen preparation packages provide the required feed gas. This package includes pre and after filters to remove particulate, refrigerant dryer to remove air borne moisture to dew point temperature (DPT) of 30EF (optional but essential in high ambient and humidity environment), and a twin tower pressure swing desiccant dryer to dry the air down to Dew Point temperature of -70EC at 100 psig, equivalent to DP temperature of -96EC at atmospheric pressure. Each train is provided with a high Dew Point temperature monitor and high DP cutout device, to trip the ozone generator system, if DP is not to the required extent. This is a safety device, and this adds to the cost, but it increases operational reliability and safety (optional). If oxygen is used as feed gas, an oxygen concentrator is added to provide oxygen on a continuous basis at oxygen concentration of 90%. Ozone concentration is 6 to 8% wt/wt if oxygen is used as feed gas, and is 1.8 to 2% wt/wt if dry air is used as feed gas.

Air to be treated and ozone are combined in a diffusion chamber. This is designed with high turbidity to ensure good mixing between injected ozone and exhaust air. The combined ozonized air is taken through a duct to enter into a contact chamber. Length of this duct should confirm to the aspect ratio L/D (Length/Equivalent diameter), to ensure good mixing between the treated gas and ozonized air.

The function of contact chamber is to allow sufficient contact time between vent gas and ozone to allow ozone to oxidize the polluting and odorous gases, and to effectively destroy air borne bacteria and viruses. The contact chamber performs extremely important function in achieving above objectives. The contact chamber is provided with multiple number of passes, to ensure effective contact between ozone and the polluting gas to promote oxidization. The contact chamber may be constructed in situ by the building contractor on large projects, or may be provided by Ruks Engineering.

Effectiveness of odor, VOC and bacteria removal, or rather the entire success of such projects depend on;

The quantity of ozone used.
Concentration of ozone.
Diffusion of ozone and effective mixing.
Sufficient contact time.

Vent gas and ozonized air mixture exiting from the contact chamber will be free of odors and pollutants, and is now ready for discharge to the environment. It is highly recommended to use a stack and discharge the vented gas, as high as possible. Passage of vent gas through the stack also provides additional contact time for oxidation, but this is not the main purpose of the stack.

CONTROLS SYSTEM
VOC Sensor or ORP probe/monitor and controller and ozone analyzer are installed in the air exiting from the stack or duct. The Sensor Controller senses the VOC in the discharge air and modulates production of ozone by the generators proportionally. Ozone analyzer tracks residual ozone concentration in discharge air and reduces ozone production proportionally. The generator is modulated from signals from both these. OSHA (Occupational Safety and Health Administration, USA) stipulates ozone level shall not exceed 0.1 PPM (100 PPB) in discharge air to environment. Ozone analyzer assists in ensuring compliance to this, and provides alarm in the event of exceedence.

The entire system is operated by our patented microprocessor controller, which regulates the output of ozone in relation to reading of VOC or ORP and ozone analyzer. This can communicate to facility operator's BMS system. If this is remote or unmanned site, it is possible to extend it for communicating to remote location. Some additional equipment may be needed to achieve this, extent of which depends on the extent of automation desired.

Other safety features include secondary high ozone concentration monitor in the vented exhaust air prior to discharge, high concentration ozone in air analyzer on ozone generator, and low concentration ozone in air analyzer for plant room, besides all other normally provided safety features.

FOR FURTHER DETAILS AND NO OBLIGATION QUOTATION FOR YOUR SPECIFIC SYSTEM, PLEASE CONTACT RUKS ENGINEERING OR OUR AUTHORIZED DISTRIBUTORS

PILOT STUDY TO DETERMINE EXTENT OF REMOVAL OF ODOR AND TOXIC GASES FROM INDUSTRIAL AND HOSPITAL EXHAUST AIR

Many industries, food processing plants, laboratories, pharmaceutical, and health care facilities discharge contaminated exhaust air to the environment. Contaminations in the exhaust air may include toxic chemicals, VOC, odor, bacteria and microbial organisms. In some instances, the air conditioning systems for such facilities are designed to operate on 100% outdoor air, and the entire room air is exhausted. This air stream diffuses readily and quickly into large volume of space upon release and is carried by drift and wind, and can reach locations at considerable distance form its source. Change of wind direction, changes in sub soil water table level, high ambient temperature, and such other external factors impact the generation and propagation of the odor. It is not uncommon is some installations to locate supply air intake system not far from the exhaust air and this promotes recirculation of contaminated exhaust air back to the air conditioning plant. This is of concern to the Public Health Departments and HVAC design engineers. The odor and bacteria released impose serious air quality problems and health hazards to the populace in the neighborhood. Due to reasons of health and hygiene, and due to municipal and regulatory requirement, it is necessary to remove the contaminants and odor from the effluent. There are few different methods available to achieve this, most are expensive in operating and some in capital cost. Whatever the method employed, it is difficult to predict the end result with any reasonable degree of accuracy. This often results in either unsatisfactory performance or the user incurring expenses more than necessary. added to this difficulty, is the fact there are no scientifically acceptable and quantifiable units developed to measure odor.

Ruks Engineering presents their solution with ozone injection technology. Of all the methods attempted, this method offers the most effective solution resulting in near total elimination of odors, VOC, bacteria and viruses. There is capital cost to reckon with. Reduction achieved in operating costs, near non odorous environment, flexibility to locate plant in areas close to high human population, improvements achieved in air quality, reduced sickness due to removal of bacteria and viruses, reduction in public health expenses, and benefit to environment offset the capital cost in a very short time.

To assist predict the final attainable level of VOC, toxicity in the air and odor in the discharged air, and to determine the quantity of ozone required and the volume of the contact chamber, Ruks Engineering has the capability perform an on site PILOT STUDY. This determines within close tolerance the likely final results, and provides substantial savings to the end user in optimizing the plant capacity and operation cost, rather than incur expenses with uncertain results. Cost of the pilot study is marginal in comparison to the cost savings.

DESCRIPTION OF RUKS PILOT STUDY
From the main exhaust air duct, a small side stream flow (about 500 Cfm) will be tapped into an ozone injection chamber. Ozone will be injected into this chamber. Devices will be made available to monitor the concentration and flow rate of ozone injected. Mixture of test stream and ozone will enter a contact chamber. Each chamber is sized to provide contact time of 2 Secs. 2 Contact chambers will be used to obtain 2 or 4 Secs of contact time.

Readings of VOC will be taken prior to entry of exhaust gas into the injection chamber and gas exiting the last contact chamber. Readings of ozone concentration will be taken on the inlet of ozone to injection chamber and on the exit from last contact chamber. Temperature reading will be monitored at entry of exhaust gas into the injection chamber. Velometer reading of air flow will be taken in the air duct exiting the last contact chamber. All the test instruments and monitors will be calibrated to NIST (National Institute of Standards and Tests, USA) traceability with calibration certificates where possible.

With these readings, Ruks will evaluate quantity and concentration of ozone required, contact time, total VOC reading prior to treatment (present VOC level), final expected level of VOC and odor from the exhaust air after implementation of the treatment, and ozone concentration if any in exhaust air after treatment. Ozone level in the exhaust air should be held below OSHA TLV level. Multiple tests will be conducted by altering flow rate of side stream exhaust air, ozone injection rate and contact time. The optimum combination of ozone injection, concentration and contact time will be presented to the client. Subsequent to this, we are glad to provide our detailed quotation for the full scale system.

All equipment such as ozone generator, oxygen concentrator, filter package, injection chamber, contact chambers, and test monitors will be provided by us.

FOR FURTHER DETAILS AND NO OBLIGATION QUOTATION FOR YOUR SPECIFIC SYSTEM, PLEASE CONTACT RUKS ENGINEERING OR OUR AUTHORIZED DISTRIBUTORS

IAQ Applications | CT Water Treatment | Odor & Toxic Gas Removal
Process Controllers | Calibration Gases