Maintaining clean air is one of today’s pressing environmental issues.
Legislation is becoming ever more stringent and the public is increasingly aware of any transgressions. All companies that operate processes with potential to pollute the atmosphere are obligated to install clean air systems that are designed for optimum performance and availability at all times. The design of a clean air system begins with an evaluation of the pollutants that are present in the gas stream. Then the best available technology to achieve compliance with environmental limits is selected. Consideration must be given to the potential for more stringent standards to be applied at a later date. Ideally the chosen system should be sufficiently flexible to meet the future standards without costly modification.
The technology selection process
The primary pollutants to be addressed are often a mixture of solid particulate material, acid gases and organic vapours and droplets.
All particulate material is categorised by the size of the particles. Current environmental regulations generally focus on particulates that are 10 microns or smaller in size (PM-10) as these have greatest impact on the human respiratory system.
Solid particulates tend to interact with condensed organic droplets to create a “sticky” material that will adhere to most surfaces with the gas stream contacts. The potential for these deposits to build up can be minimised by paying careful attention to gas velocities throughout the system, particularly in
the dry zone preceding the wet collection device. Generally the presence of organic droplets precludes the use of a dry pollution control system.
Jord has proven know-how for a wide variety of toxic, hazardous and odorous gases, including: hydrochloric and other halogenic acids; hydrogen sulphide; sulphur dioxide; chlorine; sulphuric acid and sulphuric acid mist. Jord’s packed tower scrubbers utilise a counter-current design to achieve highly efficient absorption of a wide variety of toxic gases. Removal efficiencies of 99.99% and greater are achieved in many of the above applications.
Different technical options
Chemical scrubbers
High energy venturi scrubbers
Electrostatic precipitators, wet or dry type (ESP’s, WESP’s)