This page aims to give a brief review on what is the state of the art for turbidity and its type of measurements and applications, with particular attention to the context related to wastewater
Literature Related[edit | edit source]
__________________________________________________________________________________________________________________________________ These articles show different ways of using images to detect and calculate turbidity levels in water samples __________________________________________________________________________________________________________________________________
“A novel image precessing-based system for turbidity measurement in domestic and industrial wastewater” ___________________________________________________________Abstract________________________________________________________________ Automated systems for on-site measuring of wastewater effluent turbidity are not commonly used, while those present are largely based on submerged sensors that require regular cleaning and calibration due to fouling from particulate matter in fluids. This paper presents a novel, automated system for estimating fluid turbidity. Effluent samples are imaged such that the light absorption characteristic is highlighted as a function of fluid depth, and computer vision processing techniques are used to quantify this characteristic. Results from the proposed system were compared with results from established laboratory-based methods and were found to be comparable. Tests were conducted using both synthetic dairy wastewater and effluent from multiple WWTPs, both municipal and industrial. This system has an advantage over current methods as it provides a multipoint analysis that can be easily repeated for large volumes of wastewater effluent. Although the system was specifically designed and tested for wastewater treatment applications, it could have applications such as in drinking water treatment, and in other areas where fluid turbidity is an important measurement.
- Light absorption characteristic is highlighted as a function of fluid depth
- Multipoint analysis that can be easily repeated for large volumes of wastewater effluent
- Monochrome camera
- No direct lights
- Thick water samples
- Darragh Mullins, Derek Coburn, Louise Hannon, Edward Jones, Eoghan Clifford, "A novel image precessing-based system for turbidity measurement in domestic and industrial wastewater", Water and Science Technology, Vol 77, 2018
"An underwater lighting and turbidity image repository for analysing the performance of image-based non-destructive techniques"___________________________________________________________Abstract________________________________________________________________ Image processing-based methods, capable of detecting and quantifying cracks, surface defects or recovering 3D shape information are increasingly being recognised as a valuable tool for inspecting underwater structures. It is of great practical importance for inspectors to know the effectiveness of such techniques when applied in conditions. This paper considers an underwater environment characterised by poor visibility chiefly governed by the lighting and turbidity levels, along with a range of geometry and damage conditions of calibrated specimens. The paper addresses the relationship between underwater visibility and the performance of image-based methods through the development and calibration of a first open-source underwater lighting and turbidity image repository (ULTIR). ULTIR contains a large collection of images of submerged specimens that have been photographed under controlled lighting and turbidity levels featuring various forms of geometry and damage. ULTIR aims to facilitate inspectors when rationalising the use of image processing methods as part of an underwater inspection campaign and to enable researchers to efficiently evaluate the performance of image-based methods under realistic operating conditions. Stakeholders in underwater infrastructure can benefit through this first large, standardised, well-annotated, and freely available database of images and associated metadata.
- Relationship between underwater visibility and the performance of image-based methods
- Development and calibration of a first open-source underwater lighting and turbidity image repository
- Michael O’Byrne, Franck Schoefs, Vikram Pakrashi, "An underwater lighting and turbidity image repository for analysing the performance of image-based non-destructive techniques" Structure and Infrastructure Engineering Maintenance, Management, Life-Cycle Design and Performance Vol 14, 2017
"Underwater Optical Image Processing: a Comprehensive Review"
- Review of state of the art techniques in underwater image processing
- Problems related with light’s transportation characteristics in water and the biological activity
- Image-processing approaches, such as underwater image de-scattering, underwater image color restoration, and underwater image quality assessments
- Huimin Lu, Yujie Li, Yudong Zhang, Min Chen, Seiichi Serikawa & Hyoungseop Kim,"Underwater Optical Image Processing: a Comprehensive Review", Mobile Networks and Applications,Vol 22, 2017
"Low Cost and Simple Procedure to Determine Water Turbidity with Image Processing"___________________________________________________________Abstract________________________________________________________________ This paper demonstrates a simple and cost effective procedure to measure water turbidity with image processing. Water samples were first placed inside a dark cabin before digital images of the samples were captured with smartphone camera. The red, blue and green (RGB) images were processed to obtain greyscale images, which later converted to mean greyscale index (MGI). A total of 27 formazine samples were prepared and tested to develop a calibration equation relating MGI and nephelometry turbidity unit (NTU) with regression value of R2 = 0.96. This procedure is only valid for the range of turbidity between 0 and 100 NTU. The total cost of this procedure, excluding the smartphone, was only RM16.20 which is much less than the cost of commercial turbidimeters and other proposed cost-effective counterparts.
- Measure water turbidity with image processing with smartphone camera
- Dark cabin
- RGB images were processed to obtain greyscale images
- Range of turbidity between 0 and 100 NTU
- Farah Najihah Hamidi, Mohamad Faiz Zainuddin , Zulkifly Abbas, Ahmad Fahad Ahmad, "Low Cost and Simple Procedure to Determine Water Turbidity with Image Processing", Proceedings of the International Conference on Imaging, Signal Processing and Communication, 2017
"An alternative cost-effective image processing based sensor for continuos turbidity monitoring___________________________________________________________Abstract________________________________________________________________ Turbidity is the degree to which the optical clarity of water is reduced by impurities in the water. High turbidity values in rivers and lakes promote the growth of pathogen, reduce dissolved oxygen levels and reduce light penetration. The conventional ways of on-site turbidity measurements involve the use of optical sensors similar to those used in commercial turbidimeters. However, these instruments require frequent maintenance due to biological fouling on the sensors. Thus, image processing was proposed as an alternative technique for continuous turbidity measurement to reduce frequency of maintenance. The camera was kept out of water to avoid biofouling while other parts of the system submerged in water can be coated with anti-fouling surface. The setup developed consisting of a webcam, a light source, a microprocessor and a motor used to control the depth of a reference object. The image processing algorithm quantifies the relationship between the number of circles detected on the reference object and the depth of the reference object. By relating the quantified data to turbidity, the setup was able to detect turbidity levels from 20 NTU to 380 NTU with measurement error of 15.7 percent. The repeatability and sensitivity of the turbidity measurement was found to be satisfactory.
- alternative technique for continuous turbidity measurement to reduce frequency of maintenance
- camera was kept out of water to avoid biofouling while other parts of the system submerged in water can be coated with anti-fouling surface
- webcam, a light source, a microprocessor and a motor used to control the depth of a reference object
- turbidity levels from 20 NTU to 380 NTU with measurement error of 15.7 percent
- Matthew Min Enn Chai, Sing Muk Ng, Hong Siang Chua, "An alternative cost-effective image processing based sensor for continuos turbidity monitoring", AIP Conference Proceedings 1808, 2017
"Water turbidity sensing using a smartphone___________________________________________________________Abstract________________________________________________________________ This paper demonstrates a rapid, cost-effective and field-portable smartphone based turbidimeter that measures turbidity of water samples collected from different natural water resources and in drinking water. The working of the designed sensor is based on a Mie-scattering principle where suspended micro (μ-) particles in water medium scatter a strong light signal along the normal direction of the incoming light signal, which can be detected by an infra-red (IR) proximity sensor embedded in the smartphone. Two freely available android applications were used to measure the irradiance of the scattered flux and analyse the turbidity of the medium. With the designed sensor, water turbidity variation as low as 0.1 NTU can be measured accurately in the turbidity value ranging from 0 to 400 NTU. The sensor responses for these ranges of turbid media are found to be linear. A high repeatability in the sensor characteristics is also been observed. The optics design involved for the development of the proposed smartphone turbidimeter is simple and is robust in operation. The designed sensing technique could emerge as a truly portable, user-friendly and inexpensive turbidity sensing tool that would be useful for different in-field applications.
- Field-portable smartphone based turbidimeter
- Mie-scattering principle
- Strong light signal along the normal direction of the incoming light signal, which can be detected by an infra-red (IR) proximity sensor embedded in the smartphone
- Water turbidity variation as low as 0.1 NTU can be measured accurately in the turbidity value ranging from 0 to 400 NTU
- I. Hussaina, K. Ahamadb and P. Nath, "Water turbidity sensing using a smartphone", Royal Society of Chemistry, 2016
"Automatic Detection and Assessment System of Water Turbidity based on Image Processing"___________________________________________________________Abstract________________________________________________________________ The realization of automatic control system of releasing flocculating agent is one of the bottlenecks in the automation process of waterworks. Most of waterworks in China decide the dosing amount just by artificial methods, which may lead to great subjectivity -> Problem on safety and precision To solve the problem, based on digital image processing and pattern recognition technology, the paper presents an advanced and practical automation scheme, trying to control the releasing of flocculating agent. According to the characteristics of alum images captured from waterworks, by comparing the effects of many vision algorithms, the paper selects a suitable combination and tries to implement it with EmguCV. On next step, the paper implements feature selection and classification with LibSVM. The experiments show that, the system designed in this paper is reasonable and feasible
- Digital image processing and pattern recognition technology
- Alum images captured from waterworks and tries to implement it with EmguCV
- Implements feature selection and classification with LibSVM
Cheng En, Zhang Rong-Xin, Yuan Fei, "Automatic Detection and Assessment System of Water Turbidity based on Image Processing", Telkomnika Indonesian Journal of Electrical Engineering Vol 11, 2013
Articles Related[edit | edit source]
__________________________________________________________________________________________________________________________________ These articles are brief surveys on turbidity his measurements and several applications __________________________________________________________________________________________________________________________________
__________________________________________________________________________________________________________________________________ Re-examining several turbidity measurments -> turbidity data are inconsistent with current way of measuring __________________________________________________________________________________________________________________________________
- Ben GB Kitchener, Jhon Wainwright, Anthony J Parson, "A review of principles of turbidity measurement", Progress in Physical Geography, Vol 41 (5) 2017
- Elizabeth Myre, Ryan Shaw, "The Turbidity Tube: Simple and Accurate Measurement of Turbidity in the Field", Field Engineering in the Developing World, 2016
- Richard M. Duchrow, W. Harry Everhart, "Turbidity Measurement", American Fishers Society, Vol 100 (4) 1971
__________________________________________________________________________________________________________________________________ Importante of particle sizes and their distribution on turbidity analysis Analyis on fluid mechanics -> key role on sediment cycle Turbidity levels are striclty related with the number and dimension of the particles suspended in the liquid __________________________________________________________________________________________________________________________________
- Weipeng He, Jun Hun, "Study on the impact of particle size distribution on turbidity in water", Desalination and Water Treatment, Vol 41 (1-3) 2012
- Eckart Meiburg and Ben Kneller, "Turbidity Currents and Their Deposits", Annual Review of Fluid Mechanics Vol 42 2010
- Jean P. G. Minella, Gustavo H. Merten, José M. Reichert, Robin T. Clarke ,"Estimating suspended sediment concentrations from turbidity measurements and the calibration problem", Hydrological Processes, Vol 22, 2008
- R. J. Davies-Colley, D. G. Smith " Turbidity Suspended Sediment, and Water Clarity: a review", Journal of American Water Resources Association, Vol 37 (5) 2007
-A.R. Mels, H. Spanjers, A. Klapwijk, "Turbidity-based monitoring of particle concentrations and flocculant requirement in wastewater pre-treatment", Water and Science Technology Vol 50, 2004
- Andrew C. Ziegler, "Issues related to use of turbidity measurements as a surrogate for suspended sediement", ResearchGate, 2002
________________________________________________________________________________________________________________________________ Turbidity used as a measurement for control the sewer system Using a neural network to estimate turbidity levels ________________________________________________________________________________________________________________________________
- Muhammad Sani Gaya, Muttaqa Uba Zango, Lukman A. Yusuf, "Estimation of Turbidity in Water Treatment Plant using Hammerstein-Wiener and Neural Network Technique", Indonesian Journal of Electrical Engineering and Computer Science, Vol 5 2017
- Zbigniew Mucha, Przemysław Kułakowski, "Turbidity measurements as a tool of monitoring and control of the SBR effluent at the small wastewater treatment plant: preliminary study", Archives of Environmental Protection, 2016
- C. Lacour, M. Schütze, "Real-time control of sewer systems using turbidity measurements", Water and Science Technology Vol 63, 2011
- S. Rouleau, P. Lessard, D. Bellefleur, "Behavior of a small wastewater treatment plant during rain events", Canadian Journal of Civil Enegineering, 1997
Patents[edit | edit source]
-) Stable turbidity calibration standards - US7843560B2 - United States
Inventor: Richard S. Harner, J. Keith Harris, William A. Heeschen, Mary Beth Seasholtz
Current Assignee: Dow Global Technologies LLC
- 1 to 5 sequentially-interfaced layers
- each layer independently comprises a light-permeable polymer or light-permeable interpolymer
- measured light transmission distributed in any one or more of the layers
__________________________________________________________________________________________________________________________________
-) Water turbidity measuring device, image capturing system and method based on infrared photography - CN110274893A - China
Inventor: Liu Sheng, Zhu Yuanyang, Cao Pingping, Zhao Wenzhu, Ge Fang, Zhenxiao Jian, Song Wanqian
Current Assignee: Huaibei Normal University
- infrared photography
- obtains light respectively using infrared camera and passes through the image of transmitted light and scattering light after turbidity solution
- RGB data changes to Lab color space
- emonstrates the feasibility of this method, is capable of the water turbidity of 0~1000NTU
__________________________________________________________________________________________________________________________________
-) Water turbidity detection system and the method thereof - TW201329434A - Taiwan
- Inventor: Chin-Lun Lai
- Water turbidity detection system
- Detecting turbidity of water under test (WUT), including a light emitter, an image capturing device, and a processor
- Processor calculates area parameters of the scattering blocks, and filers the scattering block via a filtering threshold to generate a statistical value
- __________________________________________________________________________________________________________________________________
- -) Machine vision suspension turbidity detection device and detection method - CN112964606B - China
- Inventor: Gao Feng, Zhang Sheng, Ma Xinyan,Dai Shaoheng, Sheng Daichao
- Current Assignee: Central South University
- Detection device comprises a suspension centrifugal separation module
- Feeding, discharging and cleaning module and a machine vision and processing module
- Optical filter is arranged between the light source and the sample detection chamber
- __________________________________________________________________________________________________________________________________
- -) Methods and apparatus for imaging in scattering environments - US9753140B2 - United States
- Inventor: William Cottrell
- Current Assignee: Raytheon Co
- Illuminator configured to produce a structured illumination pattern
- Camera configured to receive reflections of the structured illumination pattern
- Master oscillator coupled to the illuminator and to the camera and configured to modulate the structured illumination pattern and to clock the camera
- __________________________________________________________________________________________________________________________________
- -) Underwater imaging method and device according to influence of seawater turbidity - CN111586293A - China
- Inventor: Un Chao, Wang Haibo, Sun Chaojun
- Current Assignee: Shandong EHualu Information Technology Co ltd
- Acquiring image data
- Presetting and adjusting the image data according to the turbidity value of the seawater
- Outputting the adjusted image data
- Solves the technical problem underwater image data is acquired
- __________________________________________________________________________________________________________________________________
- -) Water turbidity measuring device based on infrared camera shooting - CN211877766U - China
- Inventor: Liu Sheng, Zhu Yuanyang, Pingping Cao, Zhao Wenzhu, Ge Fangzhen, Xiao Jianyu
- Current Assignee: Huaibei Normal University
- __________________________________________________________________________________________________________________________________
- -) Turbidity measurement device, turbidity measurement method, and turbidity measurement panel - WO2021235533A1 - WIPO (PCT)
- Inventor: Shoji Takeuchi, Yukiya Morimoto, Yusuke Hirata,Takashi Miyazawa
- Turbidity measurement device
- Means of a reflection region of a measurement mark M1 provided to a turbidity measurement panel
- Improves the sensitivity with which scattered light is detected within a sample S
- __________________________________________________________________________________________________________________________________
Searching & Serch Terms [Google Scholar - Google Patents][edit | edit source]
- turbidity - turbidity of water - turbidity measurement - turbidity image processing - turbidity wastewater treatment - turbidity wastewater treatment measurement
