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In many sea areas, toxic and harmful chemicals vastly exceed the standard, which not only has had a very bad impact on the survival of marine organisms, but also damages the safety of edible groundwater. With the continuous development of artificial intelligence and deep learning, the most efficient and safe method to detect seawater is with unmanned ship. By processing and fusing the images transmitted by the two radars, the common advantages of the two sensors are integrated, and the comprehensiveness of the unmanned aerial vehicle's (UAV;s) perception of the surrounding environment is improved. In order to improve the accuracy and safety of UAV offshore operations, this study designed an electric propulsion unmanned ship and its automatic control system according to the requirements of water quality sampling. Based on the small body theory, the model of an unmanned ship with the least resistance and the best safety is designed. According to the requirements of water quality sampling in sea areas, the vessel was equipped with collection and analysis systems to measure six elements of water quality. The Realizable k-e turbulence model was used to simulate the self-recovery ability of an unmanned ship under wave disturbance. Theoretically, the unmanned ship can achieve self-righting in 4.25 s. For actual navigation, the unmanned ship can effectively avoid obstacles, and the basic information on seawater quality was within the specified range. The unmanned ship constructed in this study can be used as an auxiliary tool for water quality detection. Compared with various study methods, the proposed method obtained a better performance. HIGHLIGHTS Electric propulsion; Unmanned ship; Water quality monitoring; Automatic sampling; Seawater

PLTU Teluk Sepang Bengkulu City produces heat waste dumped back into the sea which affects the quality of the water so that it has a negative impact on marine life. This study aimed to identify the quality of the water around PLTU Teluk Sepang Bengkulu City based on the physical and chemical parameters. The method used was direct measurement at the research location which is carried out at 12 measurement points,i.e 4 points around the outlet area, and 8 points in the off-shore area. The measurement result was compared with seawater quality standard for marine biota based on the Minister of Environment Decree No. 51 of 2004 and was validated by analysis of sea water quality before the PLTU had operated. The result showed that the some parameters met the quality standards for marine biota included DO of 5.62-7.82, pH and turbidity in the offshore area with each value of 7.24-7.86 and 1.68-4.846 NTU. Meanwhile, the parameters which did not meet quality standards include a temperature of 30.62-36 ºC, a salinity of 26.6-30 ‰, pH and turbidity around the outlet area with each value of 6.7-6.88 and 23.25-146.8 NTU. Based on the validation result, it showed that heat waste had a very significant effect on the physical and chemical parameters of the waters, especially on temperature, pH, and turbidity.

Scarcity of freshwater pushes countries impacted by climate change to investigate new sources of supply. Desalination plants powered by renewable energy can be the solution for a tropical developing country. Collection and treatment of seawater to produce freshwater generate an imbalanced water mass. In the case of a Reverse Osmosis Desalination Plant which pumps seawater to produce freshwater and brine as waste, the most important factor is the seawater quality, only available by observation. The design of a plant and its execution will depend on factors such as ambient temperature, salinity, and TDS. The main needs for a good multi-probe marine observation system are low energy consumption, simple monitoring, and coverage of a large area. For the sake of autonomy and ease of use, a functional and robust circuit can be set up using calibrated probes, micro-controllers, and small programmable boards. The use of programmable boards and connected probes are set up as network ‘nodes’ to send in-situ data measured from the water body. These nodes send the data using radio signal with LoRa protocol to a ‘gateway’ to store or transfer them. The parameters were measured at different time intervals, water depths, and distances from the coastline to observe how said factors affect the measurements. The results from the data collected are used to compare ocean modelling and satellite data. We present in this study the implementation of a long-range wireless autonomous sensor network and first validation tests in Jamaica and how it fills lack of information for a desalination project. Results indicate a good correlation between measure, modelling, and remote sensor. LoRa P2P network allows at an affordable price continuous monitoring of remote areas with great autonomy and resilience; results showed a successful transmission of > 80% within the network.

The port area is a diverse business district, both industry and other activities. Even though it is positioned far from residential areas, the impact of its activities indirectly still reaches the surrounding community. The environmental conditions of the port area need to be controlled routinely so that their management does not violate applicable regulations. Environmental management is needed so that risks arising from all activities can be controlled. Panjang Port as one of the well-developed fuel storage terminals as part of the Pelindo II region. This study has been designed to assess air quality and seawater quality around Panjang Port, Bandar Lampung, Indonesia. Several air quality parameters and marine water quality parameters were monitored from 2011 to 2013. The air quality sampling conducted in the fuel storage tank area and chemicals as well as supporting facilities. The air quality parameters are SO2, NO2, O3, CO, H2S, and dust. The results of data analysis showed several air quality parameters such as SO2, NO2, O3, dust, H2S, and NH3 are below the threshold of minimum quality standard. Only the CO parameter tends to increase semester to semester. The seawater quality parameters include physical, chemical, and biological quality. Almost the physical quality parameters are below the quality standard, thus the chemical quality too, except the pH and TSS tends to higher than a quality standard. In general, these studies on air quality and seawater quality at the Panjang Port have been carried out well and the results show that the environmental conditions for the Panjang Port area are still quite good, only it is recommended to add a green area around the site.

A new seawater laboratory pilot has been installed in order to evaluate the impact of the seawater quality on the performance of nanofiltration membranes and filters. The test program implemented was designed to produce the data required to optimize the design and operating parameters of a subsea sulfate removal plant, particularly with respect to the technology developed by Total, Saipem and Veolia, co-owners of the development. The equipment qualification plan is approaching completion with the development of subsea barrier-fluidless pumps, all-electric control systems, high-cycling valves operated by electric actuators and subsea water analyzers. This presented pilot laboratory study completes this plan. Nanofiltration membranes are commonly used to remove the sulfates found in seawater before the water is injected into wells. The principal advantages of relocating this equipment from topside to subsea are better reservoir sweep control, a substantial subsea water injection network reduction and savings on space and weight on the topsides deck. The move to subsea offers the opportunity to simplify the process due to improved deep water quality. This was previously demonstrated through a subsea test campaign. This new pilot study provides data both on the performance of a plant operating with different feed water quality and on the success of operating changes to further optimize the plant performance. The pilot has been installed at the Palavas-les-Flots site in France. Raw water collected from the basin was mixed with ultra-filtered water in order to calibrate the feed water quality. The pilot includes a two stage nanofiltration configuration and single stage nanofiltration unit. The two stage configuration was used to produce data for operation across an array of feed water quality and plant operating conditions. The single stage unit was used to produce data on membrane fouling over a long operating duration. Results from these tests and discussion on how this data relates to subsea plant performance shall be presented. This innovative approach enables a wide range of subsea water quality to be simulated and tested against different process configurations of the subsea unit. Indeed, for each industrial subsea application, the raw seawater quality is dependent on both the region and the depth of the seawater inlet. With this experimental data acquisition campaign and understanding of the seawater quality at inlet, the system design can be tailor-made for each future application case.

In seawater aquariums, seawater quality plays a very important role for the survival of the biota in it. There are measurement parameters that determine the quality of the seawater fit to be inhabited by seawater ornamental fish such as clown fish. Measurement parameters are such as temperature, salinity, dissolved oxygen content (DO), pH, ammonia, nitrite, and nitrate. Current technological developments make it possible to create a system that automatically conducts seawater drainage in a seawater aquarium so that the quality of the seawater remains in accordance with its measurement parameters and is fit for habitation by seawater ornamental fish such as clown fish. In this study the measurement parameters that become the reference are the temperature, pH (acidity) values obtained from the temperature sensor and the pH sensor. For normal temperatures, if the temperature is in the range of 24°C to 28°C, while for the ideal temperature is in the range of 25-27°C. For an appropriate pH in a saltwater aquarium is 7.5-8.5 with an ideal pH of 8.2. From the results of measurements made by these sensors, the value will be processed using the fuzzy logic method, then the condition of sea water quality in the aquarium can be seen from the smartphone, and when the measurement results show an inappropriate value, the system will automatically drain the water

A hydrodynamic and water quality model for seawater around Wailingding Island was configured and validated. The model was further used to predict future scenarios in terms of increasement in sewage discharge and upgradation in sewage treatment, and the corresponding impacts on coral growth were assessed. Water quality parameters of interest included dissolved oxygen (DO), biochemical oxygen demand (BOD), NH4+-N and NO3−-N. The validation results showed that the correlation coefficients for hydrodynamics and water quality were about 0.9 and 0.7, respectively; and the sewage discharge optimization should mainly control dissolved inorganic nitrogen (DIN) to support coral growth. The prediction and assessment indicated that when there was no sewage discharge, the DIN concentration was approximately 0.312 mg/L, which couldn't meet eutrophication required by coral, reducing the DIN concentration economically and effectively to decrease the impacts on coral was the goal of sewage discharge optimization. When sewage discharge rose to 1500 t/d, the DIN concentration of the area with coral distributed increased by 10.3%. Considering that local sewage treatment cost was expensive and seawater exchange capacity was strong, as well as to maximize the benefits, BOD and DIN emission control standards were proposed: 218 mg/L and 42 mg/L, respectively. These results were helpful for sewage discharge optimization and coral protection at Wailingding Island.

As the fast development of social economics, pollution accidents become more and more frequent. Yangtze estuary wetland is an important nature reserve. Evaluation of water quality becomes important in this area. However, evaluating water quality needs to concern many criteria such as chemical oxygen demand and content of harmful elements. Simply implement of criteria can cause bad results. This paper use Wavelet neural network to evaluate seawater quality of Chinese sturgeon reserve of the Yangtze estuary wetland in Spawning season successfully and calculate the quantities of floating animals and plants. The analysis also set up good mechanism of seawater quality evaluation.

The Test Bed for seawater reverse osmosis desalination plant having a capacity of 10 million imperial gallons per day, located in Gijang-Gun, Busan, South Korea, is under construction by Doosan Heavy Industries and Construction. Generally, beach well-type intake system furnishes a good seawater quality, but the amount of water which can be extracted from each well is limited by the geological formation surrounding the wells. In case of the Test Bed, unfortunately, beach well-type intake could not be adopted, therefore, in order to achieve a similar level of seawater quality, as being able to get by adopting the beach well intake, the Test Bed intake system is directly connected with a newly developed dissolved air flotation with ball filtration system. The Test Bed intake system consists of passive offshore screen, intake pipe, and air-burst cleaning system. In order to avoid possible clogging of the offshore screen by oceanic substances, compressed air-bursting system is installed onshore. In ad...

The seawater quality in Tianjin offshore area from 2006a to 2007a was evaluated based on the Grey Clustering Method (GCM). The results showed that pollution was serious in the northern coast of the study area, but other areas had good water quality. After analyzing, we found that both the selected environmental factors and the factor numbers for evaluation affected result of grey clustering, especially when the environmental factors were of great difference in the pollution level. Further study is recommended to improve and perfect the grey clustering method in order to get more unified application, and it is also beneficial for the comparison of different results.

Bathing water quality is a major public health issue, especially for tourism-oriented regions. Currently used methods within EU allow at least a 2.2 day period for obtaining the analytical results, making outdated the information forwarded to the public. Obtained results and beach assessment are influenced by the temporal and spatial characteristics of sample collection, and numerous environmental parameters, as well as by differences of official water standards. This paper examines the temporal variation of microbiological parameters during the day, as well as the influence of the sampling hour, on decision processes in the management of the beach. Apart from the fecal indicators stipulated by the EU Bathing Water Directive (E. coli and enterococci), additional fecal (C. perfringens) and non-fecal (S. aureus and P. aeriginosa) parameters were analyzed. Moreover, the effects of applying different evaluation criteria (national, EU and U.S. EPA) to beach ranking were studied, and the most common reasons for exceeding water-quality standards were investigated. In order to upgrade routine monitoring, a predictive statistical model was developed. The highest concentrations of fecal indicators were recorded early in the morning (6 AM) due to the lack of solar radiation during the night period. When compared to enterococci, E. coli criteria appears to be more stringent for the detection of fecal pollution. In comparison to EU and U.S. EPA criteria, Croatian national evaluation criteria provide stricter public health standards. Solar radiation and precipitation were the predominant environmental parameters affecting beach water quality, and these parameters were included in the predictive model setup. Predictive models revealed great potential for the monitoring of recreational water bodies, and with further development can become a useful tool for the improvement of public health protection.

Based on the analysis of seawater quality monitoring data, the grey predication method (GM (1, 1) model) was used to predict seawater quality in the Rigs-to-Reefs area of the Chengdao oil field. The result shows that petroleum pollutants and dissolved oxygen concentration will take on an increasing tendency from 2011 to 2015, and heavy metal Hg and Cd will be still kept at a low level. In addition, COD concentration has been gradually decreasing. On the whole, the prediction results indicate that the seawater quality of Rigs-to-Reefs area accords with the second-class seawater quality standard (GB3097-1997) and meets the requirement of artificial reef construction.

The seawater intake has to ensure sufficient seawater in terms of quantity and quality independently from the type of desalination plant (RO, MED, MSF) installed downstream. The best seawater quality can be reached by beach wells, but in these cases the amount of water which can be extracted from each well is limited by the earth formation, and therefore the amount of water available by beach wells is very often far below the demand of the desalination plant. In these cases the developer has the choice between (1) an intake from deep seawater with the advantage to have less polluted seawater and the disadvantage of high investment cost which normally limits this type of seawater intake to 20,000 m 3 /h; (2) open seawater intakes with the advantage of low investment cost but the disadvantage of biologically more active water which requires more efforts to treat the seawater. Offshore seawater intakes require a submerged pre-screening device minimizing the amount of sand sucked into the pipeline and ensuring that no particles able to damage or block the pump can enter. A description with pros and cons of the different available pre-screening devices will be given in the presentation, with special consideration of how the different types influence the total project cost. Open seawater intakes have to handle much higher amounts of coarse debris as well as micro organisms. The different kinds of available open seawater intakes will be presented in the presentation as well, demonstrating how efficiently and economically the different intake types fulfil this requirement.

Australia has embarked on the development of several large capacity seawater reverse osmosis (SWRO) facilities to meet future water demands and to provide water security during severe drought conditions. Two of these SWRO facilities, Sydney and Gold Coast, have installed permeate capacities of 266,000 and 133,000 m3/day respectively. The coastal areas of Sydney and Gold Coast contain sensitive marine environments that necessitated the development of intake systems that connect tunnels from the SWRO plant to offshore capacity cap intake structures. The design of these tunnel intake systems is quite unique and has been successfully designed and constructed. The design of the tunnels and intake structures are herein documented with an initial operational assessment.

Volatile phenols are a class of protoplasmic toxicants which have caused inevitable environmental problems in many sea areas. This paper analyzed the content, pollution level and distribution of volatile phenol in bottom waters Jiaozhou Bay in May, September and October 1983. Results showed volatile phenol contents ranged from 0.25~1.95 μg L -1 in bottom waters in the whole year, and were lower than Class I for volatile phenols (5.00 μg L -1 ) in National Standard of China for Seawater Quality (GB3097-1997). Jiaozhou Bay was very slightly contaminated by volatile phenols in 1983 under the impacts of vertical water's effect. Due to the flow rate was very fast in the bay mouth, in where were low value regions in different seasons in the bay mouth (0.25-1.50 μg L -1 ), indicated that there was a divergent process of volatile phenols in bottom waters

CITATION: Petrik, L., et al. 2017. Desalination and seawater quality at Green Point, Cape Town : a study on the effects of marine sewage outfalls. South African Journal of Science, 113(11/12), Art. #a0244, doi:10.17159/sajs.2017/a0244.

Shuaiba Industrial Area (SIA) accommodates 38 plants, of which 15 are located in the eastern sector and the other 23 in the western sector. The factories, being near the shore of the Arabian Gulf, discharge their wastewater directly into the Gulf after in-plant treatment. How far industrial effluents influence the marine environment was assessed using Microtox toxicity assays of seawater samples collected twice a week for six months from two stations located upstream and downstream of SIA. Out of 50 samples each collected from Station No 1 and Station No 2, only two samples from the former showed toxicity, whereas at the latter site ten samples showed medium to high levels of toxicity. The higher incidence of toxicity in the downstream area may be due to the mixing of effluent from individual discharges and indicate some inefficiency of the effluent treatment process. The study revealed that the biological assay provides effective assessment of water quality.

Orthogonal experiment is used to find out the key influencing factors of desalinated seawater quality chemical stability during distribution process. The experimental results show that in ferruginous and PE distribution systems, dosing quantity of CaCO3 is the most important influencing factor, the less important one is running time, and the least important one is velocity. Also the most optimal horizontal combinations according to different tubing are given out. Moreover, it shows that the most optimal horizontal combinations of the two tubing are different, which means that tubing also has great influence on keeping desalinated seawater stably distributed in the municipal water distribution systems.

In France, the bacteriological monitoring of recreational seawaters includes the determination of total coliforms (TC), fecal coliforms (FC) and fecal streptococci (FS). Then, the sampling locations are classified in four groups (A, B, C and D) according to the French guidelines. Data of five laboratories on the French Mediterranean coast were statistically analysed during a 3-year period (7821 samples). Correlation coefficients were calculated and principal component analysis (PCA) was determined. Correlation coefficients between TC and FC were found to be significant for all laboratories (confidence level = 99%). However, a linear relationship between TC and FC could not be calculated. PCA showed a redundance of TC and FC values to determine the fecal contamination of recreational seawaters and the average microbial pollution did not always correlate with the French classification of the seawater quality.

Sand filtration is conventionally applied to the preteatment of raw seawater in the RO desalination plant to maintain the seawater quality within the low SDI (Silt Density Index) level. However, the conventional fixed bed type has some difficulties of unstability of the filtrate quality in the backwash period and complicated operation sequence. In solving these difficulties, the applicability of the continuous sand filter has been studied with four years operation at Kure, Japan. The operational result shows that the filtrate is kept in the SDI level of four (4) which is applicable to the seawater RO desalination plant. This continuous sand filter has the advantage of stability, operation and energy saving as compared with the conventional batch type so that our developed continuous sand filter will improve plant economics for the seawater RO desalination plant.

Summary Pressure maintenance by waterflooding in some reservoirs may be considered essential for satisfactory oil recovery. The main objective of waterflooding is to place water into a rock formation at both the desired rate and pressure with minimal expense and trouble. This objective, however, cannot be achieved unless this water has certain characteristics. The water, therefore, should be treated and conditioned before injection. This treatment should solve problems associated with the individual injection waters, including suspended matter. corrosivity of water scale deposition, and microbiological fouling and corrosion. Gulf of Suez Petroleum Co. (GUPCO) is waterflooding two fields, El Morgan and July, with Gulf of Suez (GOS) water. The paper addresses the treatment phases adopted to improve seawater quality before injection, and to control problems associated with untreated seawater. Also discussed are GUPCO'S experience in seawaterfloods, problems encountered, and corrective actions taken to overcome these problems. The chemical treatment programs adopted are presented along with final conclusions and recommendations that can be applied to similar floods in Egypt with GOS. Introduction Any treatment should be designed to solve the problems associated with individual injection waters. These problems involve suspended matters in the water, corrosivity. scale deposition, and microbiological fouling and corrosion. Additional problems that may result from water injection are injection well plugging and scale deposition both downhole in the oil producers and at surface in production equipment because of incompatible water mixing. Historically, in injection projects subsurface and/or makeup waters, river waters, and lake waters have been used. Seawater also has been used in many waterfloods. Pacific Ocean water, North Sea water, and Gulf of Mexico water have been used in similar waterflooding projects. ADMA has one seawater injection project in Abu Dhabi making use of Arabian Gulf water, which also is used in a large ARAMCO water injection project in Saudi Arabia and in Dubai as well. GUPCO has two injection projects for the El Morgan and July fields involving use of Gulf of Suez water. There is no published information on the characteristics of GOS water the treatment requirement for injection, or GUPCO'S operational experience with these projects. The main purpose of this paper is to introduce some information relative to GUPCO'S seawater injection system for the El Morgan field. Water Injection and Formation Plugging The quality of an injection water depends on its properties-e.g., suspended matter (turbidity caused by organisms and particulates), corrosivity in the system handling this water, and the tendency of the water to deposit scale. Hence the net water quality is dependent on all these properties simultaneously and is primarily connected with its capability to plug the formation rocks. Jones discussed rock plugging by solids. Generally, the tendency of an injection well to become plugged is dependent on the characteristics of both the formation and the injection water. The matrix of any rock is a fine filter for solids in the injection water (free or suspended). This is generally true in spite of differences in pore sizes that formation porous rocks may have. Consequently, the formation face of the water injection well is a good filter for the suspended solids present in the injection water and can become clogged. JPT P. 1449.