Filters are used to separate extreme dusts in a gas flow from the gas via a mechanical method and to prevent environmental contamination. Acquiring maximum efficiency is dependent on which process is proper for gas separation and to make right choice. Basically a dust capture can be divided as the part where gas enters the field where the dust is separated, the section where particles are gathered and the section where the clean gas is discarded. The gas density, flow rate, temperature, viscosity, gas flow pressure, explosive and flammable properties should be known in design criteria.
In industrial filters even the cyclones are used as preliminary separator, they cannot reach the emission limit values, thus final filtration occurs in bagged filters. Filter selection requires long time experience and knowledge. In filter selection the type of gas, the particle amount within, output emission value, its temperature, the humidity and other acidic and basic values in the gas, the flammable and explosive properties are the main determinative parameters for place of installation. In filtering systems, sometimes cooling, and sometimes heating or both can be required. In filter design the most specific parameters are the properties of the explosive gasses. In these cases filters require special safety measures.
Filtering occurs in 2 ways. 

  • Surface filtration is direct filtrating process by the filtration element.
  • In deep filtration, instead of filter surface the occurring dust is filtered by the cake and this is the section increasing efficiency. However the control of the cake thickness is very important regarding preventing the pressure increase. 

  The main parameters of the filters are as follows:

  • Separation efficiency (mgr/m3)
  • Pressure reduction in continuous operation (mbar)
  • Dust separation capacity (gr/m3)

Material selection
Filter bodies are manufactured using carbon steel, corten, 304, 316, 321 series stainless materials. Which materials to be used is dependent on the gas parameters above.
In filters with low pressure cleaning air, low pressure blower, fans and in jet plus filters compressors are used.
Cleaning air, generally, is normal air however in special cases nitrogen can be used.
To reach maximum efficiency is possible with right selection and design. MDSJ, with long years of experience, is ready to resolve the hardest problems. It has successfully applied mainly in metallurgy factory as smoke suction (dust capture) system, especially the bag house filter and also the jet plus filter systems up to 5.000.000 m3/h and achieved success in dedusting.

Removal of the gas phase contaminant substances is performed via adsorption method on a solid substance or via injecting another chemical directly on the contaminant gas or via wet plugging method with water. Wet method washers use sometimes only chemicals in others chemicals can enter into reaction within water. Gas removal is conducted via these two methods. Chemical and physical adsorbers are put into contact generally with chimney gas. Dependent on the system, reaction products are aggregated as dissolved or dry salts.
Solid waste and other solid burning facilities can utilize wet and semi-dry systems for chimney gas treatment. Dry and semi-dry systems utilize generally a reaction substance with additional feeding.
In these substances for the removal of acids dead lime, for heavy metals and dioxin furans active carbon is used. These units are formed of a dust collector Cyclone or a cloth filter. For reducing emissions which method to be used is determined by details like wet spray washers, venturi washers, filled washers or dry, semi-dry adsorbers.
Advantage & Disadvantage
Besides specific advantages and disadvantages of each system, the advantages and disadvantages dependent on location and specific conditions are determined by MDSJ engineers.
MDSJ process is a leading company with profound experience in using wet scrubber, dry and semi dry methods for odor and gas removal issues in air contamination problems for 30 years.
Design Criteria
According to changing needs, in order to meet every problem it provides combined services according to customer requests with carbon steel, stainless 304-316, HRP (ctp) or PP materials body production, exproof board and circulation pumps, pH and ORP chimney gas analyzer systems, units offering complete options, special translation software (PLC scada).
Selection Criteria
Wet washers are manufactured as Venturi, Venturi Plate for odor removal and gas washing, for gasses and dusts, as Venturi Packing for gasses and dusts, as Packing wet washers for only gasses.
Wet washers are standard from 1,000 m3/h to 40,000m3/h, for larger capacities they need survey results and engineering works.
MDSJ awaits to meet your requests with pleasure in special requirements.
Acidic Gasses (HBr, HCl, HR, HCN etc.), Halogen Vapors, Sulfur Compounds, Hydrogen Sulfur (H2S), Sulfur Oxides SO3, SO4, Ammonia NH3, Amines , Chromic Acids, Ethylene Oxide, Formaldehyde CH2O, Caustic and Hydrocaustics, Methyl Prolidone (NMP, C5H9NO), Ethylene Glycol (C2H6O2)
Commonly Used Chemicals
Sodium hydroxide (NaOH), Sodium hypochlorite (NaOCI), Potassium hydroxide (KOH), Sodium carbonate (Na2CO3), Sulfuric Acid (H2SO4) and other acids, Hydrogen Peroxide (H2O2), Limewash, Cleaner and many others, In Dry Absorbers dead lime, sodiumbicarboante, active carbon, lignite, zeolit are used.
Thermal plants, waste burning facilities incinerators, treatment facilities, fertilizer factories, chemistry and paint houses, solid fuel boilers, food industry, meat and fishmeal facilities cooking boilers

Solid, Granule and dust materials are transferred with mechanical transport equipment like screwed conveyors, bucket elevators, load elevators conventionally.
Mdsj process pneumatic transport systems, by the help of air or an inert gas moving in a pipe, are very attractive transfer systems for many industrial facilities where dust and granule solids pulverized with air by low, middle and high pressure methods in a closed pipeline.
Design dependent on product properties: Product structure, particle size, physical and chemical and other properties are considered and the air volume and pressure are determined. These parameters classify the systems as dense phase transport system or dilute phase transport system.
With the Mdsj process dense and dilute phase transport systems it is possible to transfer products from one or several different points.
Dense phase;
Dense Phase Pneumatic Transfer Systems are classified according to the movement type of the solid substance in the pipe as Pulse Type or continuous type.
For this type of transfer middle and high pressures are required, thus as main movement force dry pressurized air is used. In special cases, it can be mandatory to use Nitrogen or inert gasses.
In dense phase systems are designed with relatively low transport speeds and under 5m/s. However, the start pressures can exceed 3 to 4 bars as designed proportional to the transfer ranges and line resistance. Pipe diameters are designed according to the production needs and are relatively smaller.
There is a pressurized case for taking and transferring dust and granule material. While discharging the transfer air pulse jet filters are used at discharge points, there are adjustable negative and positive operable valves at discharge points. In order to balance the transfer line pressures, prevent blockages and minimize air consumption volumetric adjustable pressure balance valves specially designed by MDSJ Process are used on the pipelines.
Phase transport (dilute )
Phase transport systems are generally designed positively, but also negative installation can be made. In accepted vacuum pneumatic transfers vacuum value is at 500 mbar lever but in special cases 700 mbar vacuum values can be reached.
In positive systems pressures up to 1200 mbar are reached, ideally transfer distance should not exceed 100 m.
Pneumatic transport operations are performed with a PLC programmed electrical control panel.
Mdsj, over 30 years, realizes installation of pneumatic transfer systems in between 10m to 500m from 1 tons/h to 300 tons/h according to the changing conditions for dust and granule materials with air mixture. The physical characteristics of the materials to be carried in the pneumatic transport system, granule materials, real mass density, shape of the particles, flow capability, sticking property of particles, temperature, breaking crushing property, sensitivity, humidity degree, flammable and explosive properties are very important for pneumatic transfer system selection, for engineering calculations after selection, for efficient operation after installation. In realizing the hardest solutions MDSJ experience is sufficient, you can contact us anytime.

These are the high efficiency equipment of the industrial facilities for cleaning in order to control the dust and to remove the spills. MDSJ Process central vacuum cleaning systems provide the following advantages for the factory inner cleaning. With the vacuum hover the dust and spills are sucked and a healthy environment is provided, the contamination is reduced before the dust spreads around. The dust collected with central vacuum hovers are recycled to the system or safely removed from the environment.
Usage Ease
Mdsj Process central vacuum hovers can easily be used by a personnel.
Personnel Saving
Mdsj Process vacuum hover can provide 60% save after installation, compared to the cleaning costs appointed for cleaning.
Suction Capacity
Due to a strong suction it can provide 15, 20 tons of cleaning per hour, their suction ranges can reach 200, 250 meters. MDSJ central vacuum hovers can provide ATEX certified installation when needed.
Production Properties
Central vacuum hovers can be produced in several types according to the operation conditions. They have 2 to 15 m3 volume and there are bottom unloading, bunkered, fixed type, electrical motor operated. Fixed type is manufactured as 1.5 m3 volume, dumping container, electric motor operated and mobile type manufactured as mounted over the trailer, hydraulic dumping, 2 to 6 m3 volume dumper, electric motor operated, or optional diesel motor operated. Usually, after the examination performed via considering the demands of the customer, the best model is offered by the engineers of MDSJ process.
Application Locations
Production fields
Conveyor belt ways and belt towers
Elevator and equipment wells
Steel factories crane paths
Foundry factories sand preparation and various fields
Coal operated thermal plants