Analysis of parameters for spray-local exhaust ventilation (SLEV) to minimize high-temperature smoke pollutants and reduce energy consumption

Abstract

Industrial buildings often face limitations in placing local exhaust ventilation (LEV) near pollution sources, which can lead to ineffective control of high-temperature smoke. This study explores the integration of spray with local exhaust ventilation (SLEV) as a solution for smoke control and energy savings. The research identified a design law for spray parameters and developed a formula to calculate SLEV ventilation flow rate that considers the impact of spray. Results indicate that the spray field overlapping coefficient plays a key role in characterizing the position and spacing of multi-nozzles. As the spray field overlapping coefficient increases, the spray dust reduction performance indicator linearly increases, while the capture efficiency follows a pattern that aligns with the Boltzmann curve model. The optimal range for the spray field overlapping coefficient to achieve high efficiency in SLEV is between 0.45 and 0.55. The formula for ventilation flow rate calculation is applicable to common conditions with smoke velocities ranging from 4 to 12 m/s (Ar: 0.0149–0.1339). SLEVs demonstrate a 35.22 % improvement in dust removal efficiency and over 20 % energy savings compared to LEVs, contributing to the development of high-efficiency, energy-saving systems for sustainable industrial production.