Plazma - Catalytic Reactor
A Plazma Catalytic Reactor is a multiple block of reactors having a certain capacity.
- Plasma-catalytic reactor
- Bypass flue
- Power unit
- Front control
- 1st stage – Anti-dust stage;
- 2nd stage – plasma-chemical stage. In this stage gas molecules are oxidised by bombarding them with fast electrons, breaking molecular bonds and forming unstable complexes and radicals
- 3rd – catalytic stage. In this stage deep oxidization, decomposition and stabilization of simple molecular forms take place.
Resultant substances including free nitrogen, carbon dioxide and water are absolutely harmless. In view of average treatment efficiency of 85-92%, except for the above gases the resultant products shall also include undecomposed molecules of starting substances in amount of 8-15% respectively.
Cost of ownership cleaning equipment
PlazKat plasma catalytic treatment plants consist of the following basic units:
Plasma catalysis reactor
Plasma catalysis reactor The PCR consists of two sections. The inside of the module, i.e. the gas-discharge module, comprises a structure made of a number of gas-discharge cells. The cells provide for the plasma chemical treatment step. The external section of the module comprises a cylinder containing catalyst.
The modules use varieties of catalysts and, as a rule, based on aluminum oxides. Catalyst modification is governed by chemistry of air to be cleaned. Catalysts do not need to be frequently regenerated. Usually, regeneration is undertaken once every 180 days (specified procedure broken down into operations is laid down in the operation manual). During regeneration a catalyst remains in the plant and the process goes at reduced flow rate of clean air in the plant for a period of 12-24 hours. Manufacturer warrants that life span of catalysts amounts to at least 7-10 years. Exposure of air oxygen molecules to low-temperature plasma results in generation of ozone molecules. Catalysts easily neutralize residual ozone and decompose it into molecular and atomic oxygen. Plant output ozone concentration does not exceed work area TLV of 0.04 mg/m3.
Power supply unit
The plant power supply unit comprises a high-voltage transformer with a control system. The high-voltage transformer is located separately from reactors and the power supply unit control block in special enclosures. There is a provision made for ВВГ 380V, 50Hz cable entry into the gas cleaning room to feed power to the PlazKat Aero plant PSU. 0.4 kV cable is laid to the control system cabinet. The high-voltage cable is laid from the transformer to the plasma chemical reactor in a metal tube and prevents induction in process electronics. The power supply unit is earthed to the grounding bus bar connected to the outside earthing device.
Operation of PlazKat Aero plant is controlled using the console indicator block and from process equipment operator's control boards in the shops which produce audible and visual alarms in case of emergency. Automatic devices of the power supply unit serve to monitor and control parameters of PCR and interlocks in PlazKat Aero plant which ensure safety of the plant operation. They are placed in the power supply unit control cabinet. The plant's emergency shutdown is undertaken if: - electric breakdown of the gas-discharge cell occurs;
- fan fails or comes to a standstill;
- power supply unit transformer fails;
- frequency converter in the control console malfunctions, and
- dust filters and catalyst are too contaminated.
PLAZKAT is designed for purification of air (gas) from the harmful gaseous substances in a concentration of 1.5 - 2.0 mg/m3 to several g/m3 and more . Low air (gas) at the entrance to the installation should not exceed 130 0C , dust ( suspended solids ) not more than 20 mg/m3, humidity should not exceed 95%. If you exceed these parameters must be applied before installing equipment to reduce the temperature, dust and humidity, respectively. When the humidity is greater than 95% should be used to install water-resistant materials.
For proper selection of equipment modifications PLAZKAT please fill in the questionnaire and asked to contact the manufacturer or its regional dealers.
Below are characteristics of some of base modifications.
All sizes can vary depending on the options and the availability of equipment placement location for the installation of the enterprise.
To assemble, undertake individual and integrated equipment tests and maintenance a provision is made for the service area 1,500 mm wide in front of the face of the PlazKat plants.
Below is the layout diagram which shows the service area in front of PlazKat plant of 15,000 m3/hour capacity.
A. INSTALLATION IN A STANDARD CONTAINER OR IN A DEDICATED GAS CLEANING ROOM
The plant is place in a standard metal container or room. The container (room) walls have entries for inlet (12) and outlet (13) gas flues. The container (room) encloses pre-filter (3), plasma catalytic reactor (6,7), power supply unit (4), and automatic control console (1).
Usually, 20and 40-feet containers are used. Containers are furnished with lighting, heating and ventilation system which allows maintenance to be performed at any time of the year. Containerization of the gas treatment plant ensures good noise insulation, electrical, explosion and fire safety and protects gas cleaning equipment from precipitation and low temperature. Air capacity of containerized gas cleaning systems varies from 3,000 to 40,000 m3/hour.
Advantages of such arrangement are as follows:
- Smaller area occupied by the plant;
- Smaller scope and shorter time of construction and installation work;
- Electrical and fire safety issues are addressed;
- Equipment tightness and, consequently, low noise level;
- Long service life of cleaning equipment, high level of automation and stable air cleaning process.
B. ARRANGEMENT IN A PRODUCTION SHOP
The plant is place in a dedicated area for ventilation, air-conditioning and cleaning equipment such as ventilation chambers and process floors. This arrangement does not require additional heating of the plant location. Equipment is installed next to exhaust ventilators. A provision is to be made for the equipment service area and a bypass (bypass gas flue) required for equipment scheduled maintenance.
The standard complete set of PlazKat Aero plant equipment includes:
1. Plasma catalytic reactor and catalyst;
2. Plant power supply unit;
3. Plant control console.
Optionally, the delivery set may include the following items (at the discretion of a CUSTOMER):
- Inlet and outlet gas flues;
- Bypass (bypass gas flue);
- Lock-up valves;
- Inlet power supply cables;
- Medium pressure exhaust fan
IMPORTANT: On commissioning equipment a medium-pressure exhaust fan is to be used which creates depression of at least 1,500 Pa at plant's rated air capacity.
If this requirement is not met, the manufacturer does not make a warranty in regard to equipment serviceability and reserves the right to terminate such warranty.
Warranty in regard to PLAZKAT AERO plants is made for a period of 12 months after plant's commissioning. We suggest to customers that a maintenance contract be concluded for the warranty and post-warranty period to include the following operations:
1. Visual inspection of the plant.
2. Inspection of power and high-voltage cables, grounding, and transformer.
3. Test of switches, indicator lights and plant's protection.
4. Inspection of gas-discharge modules:
4.1. for workability;
4.3. growth of decomposition products on contaminants;
4.4. resistance measured by a megohm meter;
4.5. working current in phases, and
4.6. condition of insulators;
5. Check of catalyst for:
5.2. growth of resins and decomposition products;
5.3. moisture on surface, and
6. Plant functional tests:
6.1. measurements of aerodynamic drag, and
6.2. determination of gas treatment efficiency.
Warranty period of installations PLAZKAT is 12 months from the date of commissioning of the plant. As during the warranty period , and at the end of this period, the consumer of our products offered to conclude a maintenance contract in the following list:
1. Inspect the exterior of the installation;
2. Checking the status of power and high-voltage cables , check the status of the grounding transformer;
3. Checking the switches, indicator lights and security system installation;
4. Checking the status of discharge modules (check of serviceability, the presence of dust , the presence of overgrowing the decay products of pollutants; Measurement resistance Megger; Checking operating currents in phases; Checking the insulators);
5. Checking the state of the catalyst (the presence of dust, the presence of overgrowing resin decomposition products, the presence of moisture on the catalyst, the presence of catalyst loss);
6. Verifying the installation (measured aerodynamic characteristics, performance measurement gas cleaning).
Really, there are a few major techniques to acquire information about efficiency of gas treatment equipment:
1. Reports on treatment of emissions in similar operations drawn up in independent certified laboratories which show treatment efficiency regarding to each substance in emissions. The report may be found on the Company's official site at www.ele-spb.ru. Below is a summary table which tabulates pollutants, major industries and treatment efficiency.
2. At CUSTOMER'S option pilot testing may be undertaken immediately at the CUSTOMER'S production facility.
The pilot air treatment plant is connected to the pollution source. This plant is capable of treating about 850 m3 of contaminated gas and air mix per hour.
Advantages of pilot testing:
- CUSTOMER'S technicians acquaint themselves with operational features of gas treatment equipment and may receive on-site engineering advice;
- Treatment of emissions from a specified source is undertaken at the CUSTOMER'S production facility;
- There is an opportunity to conduct testing under various working conditions of the source of emissions (for instance, under full load on basic process equipment which results in greater content of harmful pollutants in emissions etc.).
Bench test flowchart
As is known, emission chemistry in production facilities is multi-component and the substances belong to different classes. Our process engineers on the basis of the data provided by a CUSTOMER may create a model multi-component emission chemistry which is as close to the real chemistry as possible.
Possible model chemistry:
- alcohols (methanol, ethanol);
- ketones and aldehydes (acetone, formaldehyde);
- aromatic hydrocarbons (xylene, phenol, toluene);
- carboxylic acids (acetic acid, formic acid);
- non-organic substances (ammonia), and
- specific complex mixtures in the CUSTOMER'S facility (for instance, liquid for sleeper impregnation, aromatizing agents
Concentration of substances in the model chemistry for single-step treatment varies from 10 to 2,000 mg/m3. In bench tests a number of samples of model emission chemistry are taken prior to and after treatment in the pilot plant to be analyzed in an independent certified laboratory. In this case the reports indicate emission treatment efficiency.