Study on Pollutant Removal Efficiency of Three Ventilation Air Distribution in Large Industrial Workshop
Xi’an University of Architecture and Technology, China, People's Republic of
The industrial workshop is often a large space building, and the pollution sources are often located in the occupied zone, and the released pollutants will seriously affect the safety and health of operators. Due to the limitation of production process, it is a difficult problem for the ventilation system design of industrial workshops that how to effectively capture and control the pollutants in the occupied zone with the lowest energy consumption on the premise of not occupying the production space as much as possible. In this paper, the pollutant removal performance of three ventilation air distribution models, i.e. downside air supply–upside air exhaust, upside air supply–downside air exhaust and vortex ventilation, are compared in dealing with large-density pollutants in a large space workshop by numerical simulation. Firstly, the pollutant discharge time and pollutant concentration evolution of the three air distribution systems were compared. Then, the energy consumption difference of the three ventilation airflow organizations under two operation modes: intermittent operation with large air volume and continuous operation with small air volume was studied. The results show that for large-density pollutants, the upside air supply–downside air exhaust system and vortex ventilation system can remove pollutants in the occupied zone in a short time, which has higher pollutant removal efficiency than that of downside air supply–upside air exhaust; it is necessary to determine the most energy-saving ventilation system operation strategy by combining the pollutant release characteristics and threshold limit values(TLVs).
A Reference for Optimizing Local Ventilation: Experimental Study of Induced Airflow Characteristics during Various Liquid Metal Pouring Process
1State Key Laboratory of Green Building in Western China, Xi'an University of Architecture and Technology, No.13 Yanta RD., Xi’an, Shaanxi 710055, PR China; 2School of Building Services Science and Engineering, Xi’an University of Architecture and Technology,, No.13 Yanta RD., Xi’an, Shaanxi 710055, PR China
Contaminated airflow characteristics generated during slow and rapid liquid metal pouring processes are quite different in metallurgical plants. Due to the lack of in-depth understanding on the induced airflow characteristics during the different pouring processes, the local ventilation system performance still needs to be improved. In this study, the induced airflow characteristics during the slow and rapid pouring process were experimentally investigated through the color schlieren imaging. Three aspects were analyzed, including two different liquid morphology variations, the flow pattern evolution and average velocity variations of induced airflow in two different liquid morphology. The results show that fluid chains continuous state and fishbone discontinuous state of liquid columns were observed during slow and rapid pouring process respectively. Besides, the formation of air mass composed of contaminated airflow was illustrated during the fluid chains continuous state. Compared with a puff of air mass in the continuous state, more non-isothermal airflow were generated during the fishbone discontinuous state. Therefore, it is recommended to increase the exhaust flowrate during the discontinuous state. Finally, the average velocity of induced airflow increases with the increasing temperature difference of liquid to the ambient during the continuous state, but it will keep constant with the ratios during the discontinuous state. In summary, the obtained conclusions could help not only understand induced airflow movements and pollution source emission characteristics during liquid metals pouring process in-depth but also guide the high-efficiency ventilation system designs.
Pollutant Leakage Caused by Human Arms in a Push-Pull Ventilation Hood
1Tianjin University, China; 2Shanghai Jiao Tong University, China; 3Purdue University, United States of America
Manufacturing industry consumes a large quantity of energy on ventilation to remove pollutants and heat generated during production processes. Compared with general ventilation, local exhaust hood offers an effective way to remove pollutants and heat with reduced energy consumption. Push-pull ventilation has even higher pollutant removal efficiency than traditional exhaust hood. However, most of previous studies investigated ventilation performance of the push-pull exhaust hood without human interaction. In reality, the worker’s arms at hood opening may disturb the pull-pull airflow, and lead to pollutant leakage. This investigation used validated computational-fluid-dynamics (CFD) to study the effect of human arms on pollutant transmission of push-pull local exhaust hood. Without human arms, the push-pull local exhaust hood had a high pollutant removal efficiency and the corresponding pollutant concentration in the surrounding environment was nearly zero. However, the wake created behind the human arms caused leakage of airborne contaminant from the hood and the contaminant concentration in the surrounding environment increased dramatically. This study found the pollutant leakage increased 423 times with the human arms.
A Novel Healthy EEMs Ventilation System Using for Environment Health Safety (EHS) in Public Area
International WYNNBEAR Advanced Innovation, The US/CHN
We've created a novel everywhere multipurpose ecological-and-energized-modules (EEMs) system, in which the EEMs can be quickly paved on the ground and surface everywhere in the city, such as freeway, road, street, avenue, plaza/square, courtyard, indoor, outdoor, idle land, and spare area. The easy-to-make three-dimensional EEMs containing the types of patch EEMs, general EEMs, light-duty EEMs, heavy-duty EEMs, and heavy-duty WEEMs with the tank for water storage, etc., are widely used for buildings, construction, and civil engineering to cost-effectively solve the challenge of global warming, environmental improvement, and zero-energy, zero-water-consumption and zero-carbon with a 100% greening rate.
We have such the EEMs system combined with existing knowledge of industrial HVAC systems and contaminant control and specific disinfection measures to create a large-scale green, low-carbon, sustainable, and healthy EEMs ventilation and landscaping system with broad applications in the public area, such as industry, traffic, telecom, power, bank, and intelligence building, in which all the EEMs group are integrated as a whole with several public entrances and exiting as ventilation channels and connect to the public HVAC systems.
The selected flowers and plants in the EEMs are genetically modified and grafted, which have special functions for health protection to the COVID-19 pandemic and other chronic disease prevalence. Multiple intelligent ultraviolet devices and special disinfection measures in the EEMs system are used for epidemic prevention. The EEMs ventilation system with a beautiful and clean environment, healthy air quality, and specific specialized functions are emerging huge academic superiorities in environmental, fungal ecology, and actual applications.
Air Filter's’ Selection Study - Research Aiming Indoor Air Quality
1Anthares Soluções, Brazil; 2CDML, ON Canada
It is known that it is harmful to people to be exposed to environments with high concentrations of particulate matter (PM).
These effects may vary depending on the characteristics and particle size.
Research conducted led to the establishment of exposure limits in order to avoid risks to the health of occupants in a given environment. See ASHRAE Handbook Fundamentals 2013 - Chapter 10 and 11 (2).
Those limits were issued by many environmental control agencies. It is known that the topic is controversial, at least concerning particulate matter exposure.
The air filters in an HVAC system are essential devices for the control of the internal concentration of these contaminants.
The purpose of this article is to guide and assist the designer in the selection of air filters depending on the influence of multiple parameters. To ensure desired and acceptable indoor air quality control utilizing the Particulate Matter (PM) in suspension as a parameter.
The article looks into many of the variables that affect indoor air quality, such as airflows (Outside, Return and Supply), PM concentration outside, PM generated indoor, results for different types of filters applied to supply or outside air, and estimates the indoor concentration for overtime