Heil Series 720 Venturi Scrubbers are designed to efficiently remove fumes, dust, solids, and aerosols ranging in size down to 0.1 micron. This is accomplished by contacting the particulate laden gas stream with the scrubbing liquid (most commonly water) in a highly turbulent, high velocity venturi throat. As the droplets contact the particulate they begin to agglomerate in the diverging or evase section of the venturi. The entrained droplets now contaminated with particulate matter are removed from the gas stream by means of a cyclonic separator. The cleansed gas exits the top of the cyclone while the recovered scrubbing liquid is returned to a separate sump tank for recycle. By selecting the appropriate pressure drop (which relates directly to throat velocity) efficiencies of 99%+ can be achieved over the entire range of particle sizes.
Although standardized in size and capacity, each individual unit is custom designed and engineered to meet the specific requirements of each application.
Series 720 Applications
Heil Series 720 Venturi Scrubbers have proven performance records for fume and dust control in the fertilizer industry (both in general ventilation of specific processes), foundries, chemical plants, pulp and paper, food and food processing, smelting, frit and glass, dyestuff, aluminizing processing, galvanizing, and chemical waste incinerators.
In general, the Series 720 Scrubbers are effective for removal of submicron size particulates (both solid and liquid), heavy particulate loads that would clog other devices, and removal of gummy, tacky or scaling materials.
Series 720 Features
Principal features of the Series 720 Venturi Scrubber are:
Low maintenance cost – no moving internal parts to wear. Large orifice liquid spray nozzles are used to provide uniform distribution of liquid into the incoming gas stream. The spray nozzles have large orifices and are designed to be non-clogging. They are strategically located such that they can be removed for inspections and /or replacement without having to shut down the equipment.
High efficiency – Proper sizing and selection of pressure drop will result in efficiencies exceeding 99% for particles ranging in size down to 0.1 micron. Since the throat section is made removable, new inserts can be provided to either increase or decrease the pressure drop to meet changing gas stream conditions.
Low initial cost – Pre-engineered standard designs are available in capacities from 1,800 CFM to 67,000 CFM.
Extended service life – Individual units are designed with maximum corrosion resistance as a primary consideration. The wide selection of corrosion resistant material feature Rigidon FRP (Fiber Reinforced Polymer) as a standard material with stainless steel and other alloy construction available.
Series 720 Equipment Selection
The air or gas volume required to ventilate the process is the principal guide in selecting the proper sized scrubber. Where the specific volume of air required is not already known, references such as the Industrial Ventilation Handbook (ACGIH) should be consulted.
After determining the total air volume to be scrubbed, the efficiency of the unit must then be selected. The required efficiency will depend upon several factors including type of particulate, solubility, size distribution, density/specific gravity, quantity, concentration, plant environment, local, state, and federal codes.
Heil’s engineers will then assist in determination of pressure drop, recirculation rate, specific material selection, as well as sizing and specification of accessory items (pumps, recirculation tanks, fans, etc.) to make the system complete. Heil’s engineers will then provide a specific quotation on the appropriate scrubber and/or system.