Treatment of RO concentrate from six potable reuse facilities in the southwestern USA with a new photobiological process

2019 ◽  
Vol 19 (6) ◽  
pp. 1661-1667 ◽  
Author(s):  
Keisuke Ikehata ◽  
Yuanyuan Zhao ◽  
Harshad V. Kulkarni ◽  
Yuan Li
Keyword(s):  
United States ◽  
Reverse Osmosis ◽  
Treatment Process ◽  
The Other ◽  
Source Water ◽  
Potable Reuse ◽  
Three Samples ◽  
Southwestern Usa ◽  
Pre Treatment ◽  
Ro Concentrate

Abstract In this study, 11 reverse osmosis (RO) concentrate samples from six full-scale potable reuse facilities in the southwestern United States were treated by a new photobiological treatment process using brackish water diatoms at a laboratory scale. While eight out of the 11 RO concentrate samples were successfully treated by the photobiological treatment, the other three samples obtained from the facilities where non-nitrified effluent was used as a source water were unsuitable for the treatment due to high levels of ammonia-N in these samples. As low as 16 mg · L−1 of ammonia-N was found to be inhibitory. Lower pH was found to be undesirable because of lower calcium removal efficiency. Ozone pre-treatment and the presence of antiscalant appeared to have no impact on the photobiological process. This study demonstrated a wider applicability of this photobiological process for the treatment of RO concentrate from potable reuse facilities with different process schemes.

Study of fouling in two-stage reverse osmosis desalination unit operating without an inlet pH adjustment: diagnosis and implications

2017 ◽  
Vol 17 (6) ◽  
pp. 1682-1693 ◽  
Author(s):  
Khaled Touati ◽  
Mehdi Hila ◽  
Kalthoum Makhlouf ◽  
Hamza Elfil
Keyword(s):  
Reverse Osmosis ◽  
Treatment Process ◽  
Membrane Surface ◽  
Periodic Acid ◽  
Feed Water ◽  
Kaolinite Clay ◽  
Ph Adjustment ◽  
Second Stage ◽  
Pre Treatment ◽  
Reverse Osmosis Desalination

Abstract In the current work, the diagnosis of a reverse osmosis desalination unit is reported. Over the two last decades, the studied desalination unit was supplying a 1,200 bed hotel. The feed water was driven from a well near the sea. The desalination unit has two stages giving an average recovery equal to 81%. The behaviour of all water streams with respect to aggressiveness and scaling tendency was assessed. The second stage reject water was shown to exhibit a very high scaling behaviour with an instantaneous precipitation in the absence of feed water pH adjustment. The analyses have shown that the produced water was very aggressive. The second stage module autopsy has revealed a sharp decrease in the membrane performances because of mineral as well as organic fouling. The inorganic scale was essentially made of coesite, calcite and kaolinite clay. The presence of silica and clay was attributed to an inadequate pre-treatment process, whereas the presence of calcite crystals at the membrane surface reveals that the chemical inhibition performed at the pre-treatment process without adjusting the pH was not able to prevent calcium carbonate precipitation. A periodic acid wash of the second stage membranes is then necessary to guarantee the desired objectives of this stage.

scholarly journals An integrated approach to enhance the desalination process: coupling reverse osmosis process with microbial desalination cells in the UAE

2020 ◽  
Author(s):  
Tarun Shivakumar ◽  
Vahid Razaviarani
Keyword(s):  
Reverse Osmosis ◽  
Treatment Process ◽  
Integrated Approach ◽  
High Energy ◽  
Water Desalination ◽  
Great Promise ◽  
Future Studies ◽  
Process Studies ◽  
Pre Treatment ◽  
Feed Inlet

Abstract The growing need for better sources of fresh water has led to water desalination become a dominant technology in the water industry, especially in arid countries like the UAE. Across the globe, Reverse Osmosis (RO) has become the key method used to desalinate seawater. Due to the high energy requirements of RO desalination, the need to reduce the energy load has become a pertinent area of research. Microbial Desalination Cells (MDCs) are an emergent technology that show great promise being integrated into the RO desalination process. Studies have shown that a significant portion of the energy utilized in RO desalination could be eliminated by using MDCs as a pretreatment process. In this study, the integration of various MDC types into the pre-treatment process for Reverse Osmosis Desalination were compared and explored. Existing MDC integration setups were briefly explained. Research was split into possible configurations for the integration. This includes optimization of key parameters such as anodic inoculum, feed inlet ratios and accompanying pretreatment processes. The limitations and challenges faced in the integration were investigated and the required future studies aligned with subject was deliberated.

Working With Interpreters to Support Students Who Are English Language Learners

2016 ◽  
Vol 1 (16) ◽  
pp. 15-27 ◽  
Author(s):  
Henriette W. Langdon ◽  
Terry Irvine Saenz
Keyword(s):  
United States ◽  
English Language Learners ◽  
Language Learners ◽  
English Language ◽  
First Language ◽  
The United States ◽  
The Other ◽  
Primary Language ◽  
Second Best ◽  
Support Students

The number of English Language Learners (ELL) is increasing in all regions of the United States. Although the majority (71%) speak Spanish as their first language, the other 29% may speak one of as many as 100 or more different languages. In spite of an increasing number of speech-language pathologists (SLPs) who can provide bilingual services, the likelihood of a match between a given student's primary language and an SLP's is rather minimal. The second best option is to work with a trained language interpreter in the student's language. However, very frequently, this interpreter may be bilingual but not trained to do the job.

Armed Violence in the Ideology of Contemporary Islamic Fundamentalism - Study models

2019 ◽  
Vol 2 (4) ◽  
pp. 237
Author(s):  
Laith Mzahim Khudair Kazem
Keyword(s):  
United States ◽  
United States Of America ◽  
The United States ◽  
The Other ◽  
Islamic Fundamentalism ◽  
Islamic Movements ◽  
Important Means ◽  
Armed Violence ◽  
Goals And Objectives ◽  
At Home

The armed violence of many radical Islamic movements is one of the most important means to achieve the goals and objectives of these movements. These movements have legitimized and legitimized these violent practices and constructed justification ideologies in order to justify their use for them both at home against governments or against the other Religiously, intellectually and even culturally, or abroad against countries that call them the term "unbelievers", especially the United States of America.

SCENARIOS FOR AN EXPANDING DEMAND OF TOURISM ON THE COASTS OF CUBA

2017 ◽  
Author(s):  
Oscar Gutiérrez-Bolívar ◽  
Oscar Gutiérrez-Bolívar ◽  
Pedro Fernández Carrasco ◽  
Pedro Fernández Carrasco
Keyword(s):  
United States ◽  
The Other ◽  
Sudden Increase ◽  
Tourist Destination ◽  
Other Hand ◽  
The Usa ◽  
The Impact

The opening of relationships between United States and Cuba could be a drive for a huge increase in the affluence of tourism to Cuba and especially to the coast areas. Cuba has been for many years an important tourist destination for people from many countries, but almost forbidden for US citizens. The proximity of the USA, its amount of population as well as their great acquisition power will increase in a very substantial way the demand for accommodation and other uses in the proximity of the coasts. There will be a need to implement a package of measures that reduce the impact of such sudden increase in the coastal line. On the other hand that augment in tourism could be an opportunity to improve the standard of life of Cubans. The consideration of different possibilities of such development, the analysis of the damages that each one could cause as well as the measures that could avoid, ameliorate or compensate such effects are the goals that are going to be presented in this paper.

Reuse of Wastewaters in Agriculture by Means of Sprinkler Irrigation on a Farmland Area of 3000 ha – Large Scale Experience in Germany

1986 ◽  
Vol 18 (9) ◽  
pp. 163-173
Author(s):  
R. Boll ◽  
R. Kayser
Keyword(s):  
Large Scale ◽  
Treatment Process ◽  
Treatment Plant ◽  
Sprinkler Irrigation ◽  
Paper Briefly ◽  
Treatment Results ◽  
Sewage Farm ◽  
Western Germany ◽  
Pre Treatment ◽  
Main Components

The Braunschweig wastewater land treatment system as the largest in Western Germany serves a population of about 270.000 and has an annual flow of around 22 Mio m3. The whole treatment process consists of three main components : a pre-treatment plant as an activated sludge process, a sprinkler irrigation area of 3.000 ha of farmland and an old sewage farm of 200 ha with surface flooding. This paper briefly summarizes the experiences with management and operation of the system, the treatment results with reference to environmental impact, development of agriculture and some financial aspects.

Sign in / Sign up

Export Citation Format

Share Document