backgrounds and aims: ammonia removal from air to prevent severe damage to the environment and living organisms is very important. biofiltration is an efficient, easy, cost-effective, and environmentally friendly process for degradation of ammonia from waste air. the aim of this study is to investigate the efficiency of biological filtration using a compost and scallop bed for ammonia removal. ...

in the present study a quasi 2-d numerical model is developed for calculating air concentration distribution in rapid flows. the model solves air continuity equation (convection diffusion equation) in the whole flow domain. this solution is then coupled with calculations of the free surface in which air content in the flow is also considered. to verify the model, its results are compared with a...

The American Conference of Governmental Industrial hygienists (ACGIH) lowered the threshold limit value (TLV) for respirable crystalline silica (RCS) exposure from 0.05 to 0.025 mg m(-3) in 2006. For a working environment with an airborne dust concentration near this lowered TLV, the sample collected with current standard respirable aerosol samplers might not provide enough RCS for quantitative...

background: use of hormone replacement therapy (hrt) may increase the risk of adult-onset asthma in women. various in vitro studies have reported that estradiol stimulates human mast cell lines causing release of allergic mediators which was not observed in estrogen receptor-alpha (er-alpha) knockout mice. thus, estrogen might be a key element in occurrence of asthma. in the present study, we p...

Dehumidifier is the most important unit in liquid desiccant air conditioning system. This paper experimentally investigates the performance of an adiabatic dehumidifier using calcium chloride as a liquid desiccant. The dehumidifier inlet parameters namely desiccant flow rate, concentration, temperature, air humidity ratio and liquid to air flow rate ratio, each at four levels have been chosen a...

The filtration behaviour of woven and nonwoven fabrics at different air flow rate, dust feed rate, dust loading, time intervals and dust particles has been studied. It is observed that the pressure drop increases with the increase in airflow rate for both the woven and nonwoven filters. In general, the pressure drop in case of woven filter is found to be higher than that in case of nonwoven fil...

Axial flow fan has been used for large amount of flow rate in air handling units of industrial application fields. The fan involves a shrouding duct as flow guidance for uniform flows. Pressure difference between before and ahead of rotating blades causes the flows movements. The case where the flow resistance such as a heat exchanger is located prior to the rotors is typical in-field model for...

The two-phase gas-liquid flow properties of high-velocity open channel flows were studied experimentally in a large-size channel. The physical facility was equipped with a succession of triangular cavities associated with some strong interactions between air entrainment and flow turbulence. Detailed air-water flow measurements were collected with intrusive phase-detection probes for several flo...

A hydraulic jump is a sudden, rapid transition from a supercritical flow to a subcritical flow. At large inflow Froude numbers, the jump is characterized by a significant amount of entrained air. For this paper, the bubbly two-phase flow properties of steady and strong hydraulic jumps were investigated experimentally. The results demonstrate that the strong air entrainment rate and the depth-av...