Investigation of Ozone Concentration Measurement by Visible Photo Absorption Method

The measurement of ozone concentration based on the visible photo absorption method is investigated. An LED having an emission peak at 609 nm and a photo diode sensitive at visible light frequencies are used as the light source and the photo detector, respectively. The transmittance is measured as a function of ozone concentration, which is in reasonable agreement with the Beer–Lambert relationship. The effective absorption cross-section can therefore be estimated from the fitting procedure. The concentrations determined by both the UV and visible photo absorptions agree well with each other in the range from 7.1 to 68.4 g/m³(N). The relative error in these concentrations is discussed on the basis of the Twyman–Lothian curve. The ozone measurement for the air-fed ozone generation is also investigated. The effect of photo absorption due to NOx species is unavoidable. The present results provide useful data if the ozone measurement based on the visible photo absorption method is applied to ozone monitoring instruments or used for laboratory experiments.     

Development of a Process to Measure Ozone Concentration in Processing Water at the Point of Product Application

Ozone is an effective sanitizing agent against a broad spectrum of pathogenic and spoilage organisms. Optimization of treatment applications of ozonated water is needed for increased use in the food industry. An experimental apparatus and process has been developed to digitally measure ozone concentrations in processing water at the point of product application. Two application methods were evaluated. Effects of locally available water quality and water temperature on the ozone concentrations produced were determined. Rapid measurement of ozone concentration at the product application will facilitate the investigation of improved product quality in shrimp.     

靛蓝法测定高浓度臭氧的研究

建立了一套实用的臭氧分析方法,即用靛蓝滴定法测定高浓度臭氧,确定了吸收液使用25 mL的0.001 mol/L靛蓝溶液,并用磷酸盐缓冲溶液调节pH至6.8,温度控制在20℃,空气流量为200 mL/min,可以测定高达10 mg/L的臭氧.     

Research Note: Effects of Ozonated Water Spray Droplet Size and Distance on the Dissolved Ozone Concentration at the Spray Target

Dissolved ozone concentration (DOC) of ozonated water (OW) sprayed from four different distances using three different droplet sizes (expressed in terms of Sauter mean diameter; small, medium, large) was measured at the spray target to obtain fundamental data for improving disease control efficacy when spraying OW onto plants. DOC in the OW at the spray target decreased with decreasing droplet size. DOC was also greatly reduced at the typical spray distances of 0.50 to 0.75 m to less than one-seventh of the initial DOC (2.2 mg/L^?1) in the sprayer reservoir, and DOC one-third lower than the initial DOC was observed even at the shortest spray distance of 0.05 m for all three nozzle sizes used. Based on the results of these experiments, disease control efficacy by spraying OW can be improved by minimizing the spray distance and using a nozzle that produces a larger spray droplet size, within the range such that adhesion efficiency of OW to the leaf surface is not greatly reduced.     

Study of Ozonated Olive Oil: Monitoring of the Ozone Absorption and Analysis of the Obtained Functional Groups

The peculiarities of ozone absorption during olive oil ozonolysis have been studied by continuous monitoring of ozone concentrations at the bubbling reactor outlet. The determined amount of ozone, consumed during the ozonolysis of the double bonds, was used as alternative way for evaluation of the degree of unsaturation of the oil. The basic functional groups, products of the reaction: ozonides and aldehydes have been quantitatively characterized by means of ¹H-NMR spectroscopy, whereupon their ratio was found to be 93.4:6.6 (mol. %), respectively. The determined ratio between the cis and trans ozonides was 46:54.     

气力输送粉料流量测量的差压－浓度法

本文基于物料稀相气力输送压损比与混和比（ｍ）的比例关系式：　＝１＋ｋ·ｍ提出了一种以气固两相管程总压降（△Ｐｔ）和粉料浓度（βｓ）为测量参数的在线测量气力输送粉料流量的新方法，建立了差压－浓度法粉料流量测量数学模型及格应的测量系统。经实验验证，精度为５％，满足工业应用要求。     

Two-Stage Optimization of Coliforms,Helminth Eggs,and Organic Matter Removals from Municipal Wastewater by Ozonation Based on the Response Surface Method

In this study, a set of municipal wastewater (MWW) samples from an actual residual water treatment plant was treated by ozone. The residual water was characterized in terms of organic load and biological contaminants: total coliforms (TC), fecal coliforms (FC) and helminth eggs (HE). Initial values of these parameters were 2.8 × 10⁷ MPN/100 mL, 8.48 × 10⁶ MPN/100 mL, and 470 L^?1, respectively. The experimental setup considered the modification of pH and ozone dose as independent variables. Three different initial pH values (4.0, 7.0, and 11.0) and three different ozone concentrations (6, 15, and 30 mg/L) were used to investigate the pH ozone dose effect. The efficiency of ozone-based treatment was determined by the reduction of the microbiological indicators (TC, FC, and HE) and physicochemical parameters (COD and turbidity). The response surface method was used to determine suboptimal reaction conditions. These conditions were obtained using a two-stage procedure. The conditions under which both microbiological and organics were better removed corresponded to pH 7.8 and ozone concentration of 15.5 mg/L. A decline of biological indicators of 99% for TC, 99% for FC, and 99% for HE was obtained under the same reaction conditions. The reduction of chemical oxygen demand (COD) and turbidity was 75% and 85% under the same operation conditions, respectively.