DYNAMIC ENVIRONMENTAL DUST MEASUREMENT CHAMBER
Publication Date: 2013-Mar-11
The IP.com Prior Art Database
The invention relates to simulation, measurement and control of airborne dust in the environment such as generated by vehicular movement or other industrial activity. Dust chamber unit as shown in Fig. 1 has been designed to measure the quantity of dust emitted from under controlled temperature, air velocity and humidity conditions. The unit comprises of structures fabricated out of aluminum and acrylate sheets. The dust chamber has provisions for generating a desired temperature and environmental condition using electrical heating, water spray and air flow fans. Simulation of dust is achieved by compaction using metal roller and rubber wheels driven by FHP motors to simulate vehicle movement. Measurement and control of the environment is further achieved by instrumentation including anemometer to measure and maintain the wind velocity, relative humidity controller to monitor/maintain humidity and photoelectric device to measure the optical density or percentage transmission pertaining to dust level in the chamber. The unit provides realistic simulation of field enviroment and could be used to rapidly and reliably screen chemicals for dust control or to evaluate performance of various substrates.
The invention relates to simulation, measurement and control of airborne dust in the environment such as generated by vehicular movement or other industrial activity. Dust measurements are critical from an environmental and regulatory stand point. There are a few commercially viable equipment to measure dust in the field (US20030217588, US6853452). However, dust is difficult to measure in the laboratory environment as the creation of dust simulating the field condition is a major challenge, apart from measurement. Presently available methods are scratch test and shake test. Both these methods are helpful in either measuring the binding or wettability quotient of a chemistry that is used to bind dust particles. They do not measure the dust as no dust is created in these test conditions. Commercially available dust meters (US4993838) for the lab also measure dust but do not replicate the actual condition in the field. The invention is a design of chamber to simulate field conditions for dust generation in a controlled environment with measurement of the dust generated.
BRIEF DESCRIPTION OF DRAWINGS
Dynamic environmental dust measurement chamber is briefly described with reference to the following drawings in which:
Figure 1 illustrates design of dust measurement chamber showing instrumentation.
Dust chamber unit as shown in Fig. 1 has been designed to measure the quantity of dust emitted from under controlled temperature, air velocity and humidity conditions. The unit comprises of structures fabricated out of aluminum and acrylate sheets. A dust chamber comprises of a tray holder which can accommodate an aluminum tray of dimensions 275 x 275 x 75 mm (W X L X H) that holds a sample material that generates dust when disturbed mechanically. The chamber comprises a transparent hinged door fabricated using acrylate sheet in front for easy loading and removal of the tray. The chamber works on the principle of photo optical device that measures the haziness created inside the unit by dust particles.
The dust chamber has the following provisions for generating the environmental conditions: 1) electrical heating system (thermopile in Fig. 1) with power controller to heat/cool the sample and to vary the temperature of the sample from 30°C to 50°C or other suitable conditions covering the environment to be simulated as desired, 2) water spraying system that works on the principle of charge metering mode to spray water and could incorporate dissolved chemistries for spraying across the tray, 3) 2 water tanks - to store 2 l of water and 4) fan with speed control - to generate different air velocities depending on the needs.
Simulation of dust is achieved by 5) metal roller of length 270 mm and 50 mm diameter connected to the housing that helps generate a maximum force of 100 kg to roll over and compact the sample material in the tray after water/ chemical treatment and 6) rubbe...