A comparative study of RO and MSF desalination plants

A comparative study of RO and MSF desalination plants

The prospects of using nuclear energy in Saudi Arabia for desalination and electric power generation represent a challenging engineering problem. Three specific issues have been considered for a dual-purpose plant, namely: (1) Impact of the availability and reliability of the desalination plants, (2) Integration of the desalination and power production stages, and, (3) Safety considerations of dual systems;The operational history data of the Jeddah desalination plants are studied, to determine the reliability of a multi-stage flash (MSF) desalination plant and of a reverse osmosis plant (RO);MSF plant performance, operation conditions, and the most common causes of deviation from plant performance standards are presented. Actual operation data from an MSF plant are analyzed. Potential problem areas and critical components are identified, and failure rates are estimated;Fault tree techniques are used for major systems in both MSF and RO plants, and a quantitative evaluation is performed using PREP-KITT computer codes to assess the probability of failure of the MSF and RO plants. The results of such studies showed that the major contributors of unavailability are pump failures, screen failures, pipe leakages, motor operated valve failures, and tube leakages. Recommendations for improving the reliability of MSF systems are given;The reliability and operational experience of the RO plant are analyzed, and the results of the RO plant availability analysis are given for four cases of operation in which failure contributors are membrane fractures, pump failures, diesel engine failures, and pipe leakages;The analysis of the operation history of both desalination plants revealed some very important factors which have been considered. The implications of dual-purpose nuclear desalination plants are discussed for technical, safety, and operational aspects of these plants. Also, the schemes of integration of nuclear steam supply systems with the MSF plant are presented. A comparison of RO and MSF processes from the point of view of reliability, safety, and compatibility with nuclear power as an energy source is presented. Finally, the overall availability of nuclear desalination plants is estimated based on actual data from operating experience.

Hybrid desalting systems

Coupling of a nuclear reactor to hybrid RO-MSF desalination plants

This paper presents a methodology and practical guidelines for developing predictive models for large-scale commercial water desalination plants by (1) a data-based approach using neural networks based on the backpropagation algorithm and (2) a model-based approach using process simulation with advanced software tools ASPEN PLUS and SPEEDUP and compares the relative merits of the two approaches. This study utilizes actual operating data from two of the largest multistage flash (MSF) and reverse osmosis (RO) desalination plants in the world. Our resulting neural network and process simulation models are capable of accurately predicting the actual operating data from commercial MSF desalination plants, but the accuracy of a neural network model depends on both the proper selection of input variables and the broad range of data with which the network is trained. A neural network model can handle noisy data more effectively than statistical regression and performs better in predicting the performance variables of both MSF and RO desalination plants. Our neural network model compares favorably with recent neural network models developed by others in accurately predicting actual operating data from commercial MSF desalination plants. When compared to a data-based neural network, a properly validated model-based process simulation (as in the case of MSF desalination plants) can more effectively quantify the effects of varying operating variables on the desalination performance variables. When it is difficult to develop a model-based process simulation (as in the case of RO desalination plants), we can use a data-based neural network to accurately predict the desalination performance variables.

Novel Tri Hybrid Desalination Plants

Optimum design for a hybrid desalting plant

Exergy and thermoeconomic evaluation of MSF process using a new visual package

Performance test of a sea water multi-stage flash distillation plant: Case study

6. For a machine for grinding bark; merrit hurd, Augusta, Oneida county, New York, May 5

Potential of nuclear desalination in the Arabian Gulf countries

Control of multi-stage flash desalination plants: A survey

Optimal design of hybrid RO/MSF desalination plants Part III: Sensitivity analysis

Physical and chemical assessment of MSF distillate and SWRO product for drinking purpose

Over the past decade, the author, Roger Francis, has looked at some very expensive corrosion failures in desalination plants. Avoiding Corrosion in Desalination Plants tells the reader how to avoid existing corrosion problems and how to avoid them in new builds. This book looks at corrosion problems specific to MSF, MED, and SWRO desalination plants, describing their causes, some solutions, and the relative performance of various materials. It gives advice on procuring materials for desalination plants to avoid quality problems. The world’s population is steadily increasing and with it is an increasing demand for water—for both drinking and irrigation. In many areas of the world, particularly in warmer climates, there are limited sources from rivers and wells, so desalination is being increasingly used to produce water to satisfy both requirements. Although desalination is sometimes carried out on brackish waters and highly saline well waters, most desalination plants generate fresh water from seawater. There are three main processes used in desalination plants, the oldest of which is multistage flash (MSF), where the water is essentially boiled at low pressure and the steam that flashes off is condensed for drinking water. The second process is multiple-effect distillation (MED), in which low-pressure steam is used to force evaporation of seawater and the vapor is then condensed for drinking water. Although actual MSF and MED plants (large-scale) are land based, small-scale units have been fitted to large ships, such as cruise liners, to generate fresh water. The third process is seawater reverse osmosis (SWRO), where chloride is selectively removed from water by forcing it at high pressure through a special membrane. This method involves no heat transfer but requires enough electricity to power the high-pressure pumps that are required. All three of these methods have advantages and disadvantages. This book looks at corrosion problems specific to MSF, MED, and SWRO desalination plants, describing their causes, some solutions, and the relative performance of various materials. It gives advice on procuring materials for desalination plants to avoid quality problems.