Scale formation represents a major operational problem encountered in thermal desalination plants. Scale may form because of the composition of the make-up, but mostly develops as a result of further change occurring during evaporation. Scale formation is mainly caused by crystallization of alkaline scales, e.g., CaCO3 and Mg(OH)2 and non-alkaline scale, e.g., CaSO4. The formation of CaCO3 scale strongly depends on temperature, pH, and the release rate of CO2 as well as on the concentrations of HCO3-, CO32-, Ca2+, and Mg2+ ions. Scaling in industrial processes is affected by the following factors: (i) bulk variables and composition, i.e. CaCO3 precipitation potential, pH buffering capacity, chloride and sulfate concentrations and concentration of dissolved oxygen, (ii) thermal effect, i.e. heat flux, surface temperature and bulk temperature, (iii) flow field, i.e. velocity of flow and solid/liquid interface conditions and (iv) substrate properties, i.e. materials properties and surface conditions.
In previous works, Al-Rawajfeh et al. [1-3] have modeled the CO2 release rates in multiple-effect distillers (MED)distillers. This model did not account for the deposition of alkaline scale and its effect on CO2 release rates. Calcium carbonate and magnesium hydroxide were assumed to precipitate at negligible rates. Recently, Al-Rawajfeh [4,5] developed a model to simulate the simultaneous release of CO2 with the deposition of CaCO3 and investigated their mutual release-deposition relationship in MED [4] and in the flash chambers in MSF distillers [5]. The influence of CO2 injection on the carbonate chemistry and the scale formation were also studied [6]. The model begin to calculate the CaCO3-Mg(OH)2 (alkaline) scale in the brine chambers, because part of the scale is deposited there and will be reduced from the total scale precipitate or reduce the ions available to precipitate CaSO4 scale inside the tubes when it is recycled with the make-up. Details on the CO2 release and alkaline scale modeling can be found in previous works [1-6].
REFERENCES
[1] Al-Rawajfeh, A. E., Glade, H., Ulrich, J., CO2 release in multiple-effect distillers Controlled by mass transfer with chemical reaction. Desalination, vol. 156, PP. 109-123, 2003.
[2] Al-Rawajfeh, A. E., Glade, H., Qiblawey, H. M., Ulrich, J., Simulation of CO2 release in multiple-effect distillers. Desalination, vol. 166, PP. 41-52, 2004.
[3] Al-Rawajfeh, A. E., Glade, H., Ulrich, J., Scaling in multiple-effect distillers: the role of CO2 release. Desalination, vol. 182, PP. 209-219, 2005.
[4] Al-Rawajfeh, A.E., Modelling of Alkaline Scale Formation in Falling-Film Horizontal-Tubes Multiple-Effect Distillers. Desalination, vol. 205, PP. 124-139, 2007.
[5] Al-Rawajfeh, A.E., Simultaneous desorption-crystallization of CO2- CaCO3 in multistage flash (MSF) distillers. Chem. Eng. Proc., Proc. Inten., vol. 47, PP. 2262-2269, 2008.
[6] Al-Rawajfeh, A.E., Al-Amaireh, M. N., The influence of CO2 injection on the carbonate chemistry and scaling in multiple-effect distillers. Desalination & Water Treat., vol. 7, PP. 191-197, 2009.
Cost of course depends on capacity and desalination method. Shoaiba Desalination Plant, Saudi Arabia, uses MSF Flash technology with a total output capcity of 128 million gallons per day. Cost 1.6 billion $US.
Yes, New Zealand has a fractional desalination plant located in the town of Taranaki. This facility utilizes advanced desalination technology to provide a sustainable water source, particularly during periods of drought or water scarcity. Fractional desalination helps in producing freshwater from seawater while minimizing environmental impacts. The plant plays a crucial role in addressing water supply challenges in the region.
Multi-stage Flash (MSF) Desalination
to create vacuum for decreasing the boiling point. it works the base of converging-diverging procedure.
The biggest problem with desalination plants is their high energy consumption, which often leads to significant operational costs and environmental concerns due to greenhouse gas emissions. Additionally, the process generates saline brine waste that can harm marine ecosystems if not properly managed. Furthermore, desalination plants can be expensive to build and maintain, making them less accessible for many regions.
No, living coral is not a tiny plant. It is comprised of a group of animals inside of shells made of calcium carbonate.
a pumping plant because a desalination plant costs alot and they produce brine
It is due to the amount of energy needed to run a desalination plant, as well as the fines that have to be paid due to the amount of air pollution a desalination plant gives out.
Calcium is a chemical element with the symbol Ca.
Calcium-rich soil is commonly referred to as calcareous soil. This type of soil contains high levels of calcium carbonate, which is beneficial for plant growth, especially for calcium-loving plants.
how to design a desalination plant of 2000 tonnes per day production of distillate ,the desalination type of evaporation multi stage ,,with material balance,?
Lime (calcium carbonate) is commonly used to neutralize acidic soil. Applying lime increases the soil pH, making the soil less acidic and more suitable for plant growth.
Garden Lime, also known as Calcium Carbonate, is simply CaCO3.
Calcium Carbonate decreases organic matter and grain yields so that although there is a lot of leaves about - the soil won't be too acidic. Calcium Carbonate may be particularly effective with soil under a tree.
The government of Saudi Arabia has just authorized the construction of a new seawater desalination plant.
what does they currently building a desalination plant in victoria
Lime (calcium carbonate) is commonly used to decrease acidity in fields and gardens. It helps to raise the pH of the soil, making it more neutral and improving plant growth. Lime can be applied in various forms, such as ground limestone or dolomitic lime.