Parametric distributions of a horizontal-tube falling film evaporator for desalination

Abstract

A B S T R A C TThree independent experiments which correspond to the characteristic study on the performance of the horizontal-tube falling film evaporators were carried out, and each came out with a validated model for its performance prediction. A comprehensive distributed parameter model was developed based on the above three models to simulate a large tube bundle consisting of 160 rows and 80 columns aluminum-brass tubes in a horizontal-tube falling film evaporator. The simulation was conducted with the superficial evaporation temperature on the shell side of 60˚C, the superficial overall temperature difference of 3.0˚C, the inlet brine salinity of 30 g/kg, the inlet brine spray density of 0.06 kg/m s, and the maximum steam inlet velocity of 40 m/s. The non-uniform distributions of several thermal parameters are presented and discussed.

Current Trends for Biological Antibiotic Pharmaceutical Wastewater Treatment

“…In response to increasingly stringent requirements concerning the quality of municipal effluents and the growing importance of wastewater reuse, biological technologies such as anaerobic/aerobic and combined biological technologies have been extensively studied. In fact, many reports demonstrate that biological treatment methods have played important roles in antibiotic wastewater treatment [12,13].…”

Impact of the geometric parameters on the thermal performance of a large-scale falling film evaporator for desalination

“…Several validated correlations were obtained from the set of experiments and a comprehensive DPM was developed to simulate the heat transfer performance in a large-scale horizontal-tube falling film evaporator. In previous work, the flow charts for the three experiments and the related correlations as well as the algorithm were described in detail [13]. The model and the operating conditions are briefly summarized as follows: the physical model is a large-scale horizontal-tube falling film evaporator containing a tube bundle that has 160 rows and 80 columns of tubes.…”

“…It was concluded that the local heat transfer coefficient decreases with the increment of the tube row number mainly due to the weak in the seawater film turbulence outside the tubes. On consideration of the inter-tube vapor flow, the distribution of the heat transfer coefficient along the tube column direction of a falling film tube bundle were recently investigated by Gong et al [12,13]. A smaller variation range of heat transfer coefficient was found along the tube column direction than along the tube row and length directions.…”

Experimental Study of Heat Transfer and Hydrodynamics of Falling Film on a Novel Design of Helical Finned Tube Evaporators

“…To enhance the density of evaporators with falling film new structures of promoters of turbulence were developed allowing to influence flow favorably, to raise the heat exchange area and to improve the convective heat transfer coefficients and to increase of the density of the heat flux. L.Cong et al [1] carried out three independent experiments which correspond to the characteristic study on the performance of the horizontal-tube falling film evaporators. The simulation was conducted with the superficial evaporation temperature on the shell side of 60°C, the superficial overall temperature difference of 3.0°C, the inlet brine salinity of 30 g/kg, the inlet brine spray density of 0.06 kg/m s, and the maximum steam inlet velocity of 40 m/s.…”