Based on New Discoveries and Patented Innovations in Electrofluidics, the CCS Uses a Unique Method of Charging Droplets and Capturing Particles.
There is no particle charging in the CCS, only charging of the water droplets. While most exhaust streams will have a majority of neutral particles, there is often a fraction of already-charged particles. The CCS can capture both. A. The contaminated air stream enters the Preconditioning Chamber (PCC) spray tower, counterflow to jets of water spray.
Coarse particles are removed by impact with the (uncharged) spray. Fine and ultra fine particles will not be collected by spray jets. Cooling of the exhaust steam to the saturation point occurs. Ultra fine particles of a few hundredths of a micron are grown to a few tenths of a micron, the size at which they can be removed in Steps B & C. The primary stage of gas scrubbing takes place. These cause acid fumes, or any soluble gas. From the PCC, the air stream enters the first Cloud Generation Vessel (CGV #1) mixing with the cloud of positively charged water droplets created by the Charging Head.
B. CGV #1 performs several functions.
Neutral particles, including fine and ultra fine particles, are attracted to the droplets and captured through monopole induced dipole charging forces. Particles in the exhaust that are already negatively charged are electrostatically attracted to the positive droplets and captured. A secondary stage of gas scrubbing takes place. Exiting CGV #1, the air stream enters CGV #2 and is mixed with a cloud of negatively charged droplets.
C. CGV #2 performs several functions.
Residual neutral particles, including fine and ultra fine particles, are further removed through induced dipole forces. Particles in the exhaust that are already positively charged are electrostatically attracted to the negative droplets. A final stage of gas "polishing" scrubbing takes place. The cleaned air passes through a mist eliminator and goes to the wet stack.
Cloud Chamber Technology: A New Approach to Fine Particles and Ultra Fine Particles
The Cloud Chamber Scrubber® (CCS®) was developed by Dr. Clyde Richards, Atmospheric Physics, Inc. (Albuquerque, NM), and is licensed to Tri-Mer Corporation.
With its broad treatment capabilities, the CCS is an effective air pollution control solution for any exhaust application that produces coarse, fine or ultra fine particles, including difficult applications such as diesel exhaust and glass furnace exhaust.
CCS technology works by passing the dirty gas stream through a chamber that contains a carefully generated “scrubbing cloud” of high-density, charged water droplets. Inside the Cloud Chamber system, billions of charged droplets rapidly interact with the particles in the process stream. When a particle and a droplet pass within 20 microns, electrical forces cause mutual attraction and the particle (being less massive by orders of magnitude) is pulled into the droplet. Each individual water droplet becomes a particle collector.
The droplets collect particles as they interact with the process gas stream, then fall into the sump at the bottom of the system. Captured particles agglomerate within the sump, settle out, and are removed as a low volume slurry from the bottom. Relatively clean water from the top of the sump is re-circulated by pump to the charging grid, where it is recharged, completing the cycle.
A low concentration of particulate does not affect the ability to charge the water, so relatively clean water from the top of the sump is filtered for very coarse particles and re-circulated to the charging nozzles.
Since the charged droplets act as particle collectors, there is no need for fibrous filters, collector plates, venturi throats, layered pads, bags, or cartridges.
Several factors are involved with optimizing the effectiveness of a particular Cloud Chamber application. These include droplet size, droplet charge, particle size, particle charge, particle retention time, and electric field effect. For each application, a computer simulation can be run to analyze these factors, along with expected inlet loading, gas type and concentration is quickly completed.
Gases to be treated, if any, are taken into consideration. These simulations help determine the ideal system configuration in terms of recirculation flow, gas-to-cloud contact time, and vessel size. Any fine-tuning of parameters during operational start-up using Tri-Mer's advanced real-time particle measurement instruments.
Advantages of Cloud Chamber Scrubbers
Introduction Particles are, by definition, both solid bits and tiny liquid droplets of condensed pollutants. Size definition for both solid particles and liquid particles has been set by the U.S. EPA as follows:
Coarse = particles 2.5 micron & larger Fine = 2.5 micron & smaller Ultra fine particles = 0.1 micron & smaller Gases usually refers to acid gases and include toxic vapors that can condense into liquid particles. Caustic fumes such as ammonia and its compounds are sometimes called gases.
Coarse particles are easily removed by the CCS. Particles between 0.1 and 2.5 microns are removed at very high efficiencies, often 99% or better. Remarkably, even ultra fine particles as small as 0.01 micron can be effectively treated after controlled agglomeration growth in the system’s “pre-conditioning” section. On some applications, the CCS can handle inlet mass loadings as high as 2,000 mg/m3, reducing mass emissions to below 5 mg/m3. This is equivalent to 0.9 grains/ft3 reduced to 0.002 grains/ft3.
Competitive Initial Costs CCS is a cost-effective, multi-pollutant technology. When gas scrubbing is required in addition to particle removal, further savings are realized because the CCS eliminates the need for a separate scrubber.
Low Operating Costs (Electrical)
The CCS offers significant operating cost savings. A proprietary, patented method is used to charge the water droplets. The system’s charge generation modules require a maximum of 10 watts of power per 1000 cubic feet per minute (cfm). An ordinary 100 watt light bulb draws as much power as a charging head for 10,000 cfm. Power consumption for charging is usually 1% or less of that required by ESP technology. The key is that only water droplets are charged, and that the charge generating module works under controlled steady-state conditions, putting charge on a highly receptive medium.
The main power draw in a CCS system is the pumps that recirculate water to the heads. The CCS recirculates (but does not consume) more water than wet ESP. The net result, however, is that the CCS still uses substantially less total power to operate. Maintenance costs are also much lower. The differences are dramatic.
Low Operating Cost (Pressure Drop)
The CCS chambers are completely open, with no packing or baffles. Pressure drop is very low, less than 1.5-inch w.g. This results in low fan energy requirements. Most of the pressure drop comes from a mist eliminator at the end of the system and the connecting ductwork. The obstruction-free vessels themselves create nearly zero pressure drop.
Low Operating Costs (Maintenance)
The open chambers of the CCS reduce typical maintenance problems because there is no fouled packing to clean or biological growth problems to treat. Most importantly, the system has a minimum number of moving parts – only a reliable standard recirculation pump on each vessel and an ID fan. The charging heads themselves are very durable and simple in design, having no moving parts. The power supplies are small, the size of a shoebox. The nozzles are inexpensive standard issue and are protected from plugging by redundant prevention approaches. Nozzle replacement has been a non-issue even for units operating 24/7 for over five years.
Application Flexibility A CCS can be used as a stand-alone scrubber or as a tail gas scrubber for existing systems. With the addition of pH adjustment chemicals to the sump liquid, CCS can treat scrubbable gases (such as “ammonia slip” and sulfur dioxide, S02) in addition to fine and ultra fine particles. Because of the small pressure drop, using a CCS as a tail gas scrubber usually does not require additional fan equipment.
The CCS smoothly handles changes in flow volume and can be turned down over a wide range, typically 10- to -1 or better. Charging scheme does not change. Moreover, CCS is relatively unaffected by changes in particle loading and loading constituents (including TAC) due to the physics of charged clouds. There is built-in redundancy in a standard 2 CGV configuration because a single CGV already has a very high capture efficiency.
Typical Application for CCS include: • Large stationary diesel • Glass furnace emissions • Boiler MACT compliance • Solar panel manufacture • Syngas cleaning • Solid fuel and biomass boilers • Oil and gas fired boilers • Waste incinerators • Abrasive production • Smelters and foundries • Chemical manufacturing • Curing ovens, dryers, rotary kilns • Plastics Manufacturing • Sulfuric and nitric acid production • Diesel test cells • Diesel from ships at port • Diesel from locomotive engines • Many others with submicron PM • Wet electrostatic precipitator replacement
Typical Pollutants Removed by CCS include: • Diesel emissions • Inorganic salts • Silicon dioxide, silica • Metal oxides • Syngas pollutants • Heavy metals • Ammonium salt particles • Condensable hydrocarbons • Byproducts of combustion • Carbonyl sulfide (COS) • Acid gases such as HCl, HF, H2SO4,HNO3 • Sulfur dioxide (SO2) • Chlorine gas (Cl2) • Hydrogen sulfide (H2S) • Ammonia • Many others