What are the advantages and disadvantages of using inorganic ceramic membrane systems for saltwater filtration?

Why isn’t there anyone replying? I still want to learn* learn*

When using ceramic membranes, good quality salts are required, and a larger design margin must be taken into account!

The advantage of ceramic membranes is that they can handle the worst-quality raw salts; however, the worse the quality of the salt, and the more severe the inversion of calcium and magnesium levels, the lower the designed filtration flux.

Read. It’s a shame no one posted an explanation

Advantages: low space requirement, low investment cost, and high filtration precision. Disadvantages: Maintenance is troublesome, and it’s hard to locate leaks in the membrane.

There are posts about ceramic membranes on the forum; just search for them

Comparison of the main characteristics of inorganic membranes and organic membranes: Inorganic membranes have the following main characteristics:  A narrow pore size distribution, resulting in high separation precision. Inorganic ultrafiltration membranes with a pore size of 50 nm can completely remove solid suspended particles from brine, making the filtered brine clear and transparent, which facilitates the efficient operation of ion-exchange membrane cells.  Resistant to acids and alkalis, solvents, oxidation, and high temperatures. The inorganic membrane support is made by sintering high-purity imported α—Al2O3 at temperatures above 1600°C; its operating temperature can generally reach 400°C, with a maximum of up to 800°C. It can operate within a pH range of 0–14 and is capable of being used in highly oxidative environments.  It has high mechanical strength, as well as good wear and erosion resistance. The inorganic membrane can withstand operating pressures of up to several dozen kg/cm2, and it can also be backwashed.  High permeation flux: Inorganic membranes have a very high porosity, exceeding 35%, which results in a high flux for saline solutions. The saturated sodium chloride saline flux of inorganic ultrafiltration membranes with a pore size of 50 nm is greater than 700 L/m2·h.  It can be washed repeatedly and regenerated at high temperatures to restore its permeation flux, resulting in a long service life. Acid-base cleaning methods can effectively restore the membrane’s permeation flux, allowing its service life to exceed 5 years.  Resistant to microbial degradation and erosion; it does not interact with microorganisms, making it highly suitable for the fields of bioengineering and medical science. Even if not used for a long time, there is no need to use a special maintenance fluid for upkeep.  Cross-flow filtration is employed. This type of filtration, also known as tangential flow filtration, is less sensitive to changes in the size, density, and concentration of suspended particles compared to end-filtering methods. It allows the system to operate continuously for extended periods without the need for frequent backwashing or removal of sludge, making it suitable for large-scale production applications.  The integrated separation equipment has low operating energy consumption and low costs for cleaning and regeneration; the effective parallel and series combination of membrane modules greatly reduces the energy consumption per unit area of membrane. Cleaning costs can be reduced through ordinary chemical cleaning.  The equipment occupies little space, facilitating automated control. Advantages of the organic membrane process  The process is simple and has a short flow path; the suspended solids in brine are reduced from 1000–10000 mg/L to below 1 mg/L, allowing it to be fed directly into the ion exchange resin column.  Stable filtration accuracy and stable quality of brine.  High processing capacity, which saves companies on investment in upgrades.  Simple to operate with fully automatic control; compared to traditional processes, it eliminates the need to clean the clarification tank, cellulose pre-coating filters, or sand filters, **reducing the workload for workers.  It occupies a small area, making it convenient to implement in the renovation of existing factories.  A preprocessor is used to eliminate the effects of free salts, flocculent water-insoluble substances in brine, high magnesium levels, and organic matter, and to reduce the impact of operational fluctuations on subsequent purification processes.  It reduced the requirements for the quality of raw salt, expanded the range of salts that could be used, bringing considerable economic benefits to enterprises.  High-quality brine extends the membrane’s lifespan and reduces power consumption.  Suitable for the purification of various raw materials, including brine, brine mixed with sea salt, lake salt, sea salt, and other types of saline solutions; it can be applied in similar processes such as salt production, the production of sodium and potassium metal salts, and nitrate production. The HVM membrane brine purification process involves pretreating crude brine and performing primary membrane separation to obtain purified brine that meets the requirements for feedstock to ion exchange resins. This process is simple and has a short workflow; liquid-solid separation is completed in one step, eliminating the need for sand filters or fine filters. It also eliminates the requirement for pre-coating with cellulose and prevents secondary contamination by silicon. It features high filtration precision, stable brine quality, and high processing capacity. To date, 265 HVM brine purification projects have been approved, resulting in a total brine treatment capacity that enables the production of 28.36 million tons per year of ion-exchange membrane caustic soda; of this amount, over 20 million tons per year are already in operation. The HVM membrane has been in use for over 7.5 years and is still being utilized, with the quality of the saline remaining consistently within acceptable standards. The HVM membrane features a unique tubular integral structure and is made entirely of perfluoro material. It has been in continuous operation for over 7.5 years in industrial plants used for the purification of chlor-alkali brine and calcium-based denitration of brine, and it is still in normal use to this day without any issues such as membrane peeling, tearing, or corrosion. The membrane modules are efficient, long-lasting, and offer stable and reliable performance.

Ceramic membrane maintenance is rather troublesome; if the sealing of the membrane tubes is poor during operation or if the tubes break, it becomes very problematic

Disadvantages: 1. Ceramic membranes require high-quality raw salt; otherwise, the backwashing frequency will be too high, which affects the yield of refined brine. Additionally, the solid content in the crude brine increases rapidly, and the frequent need to acid-wash the equipment also impacts the lifespan of the membranes. 2. The ceramic membrane process has a short workflow and requires more precise control; any issue can directly affect the electrolysis stage. 3. Ceramic membranes are also vulnerable to organic contamination; without a pretreatment unit, the free chlorine level in the baffled tank needs to be 30 ppm, and the consumption of sodium sulfite is higher compared to the KAI membrane process. 4. Due to the high operating pressure, if the sealing ring of any membrane tube is damaged or the membrane tube itself ruptures, it will cause the permeate fluid from the entire system to become turbid, requiring the shutdown of the equipment for maintenance; this aspect is not as convenient with Kai Membrane. Advantages: 1. High degree of automation, which reduces labor intensity and ensures stability during normal operation. 2. It requires less space and a smaller initial investment. 3. Based on the operating performance of our factory, the filtration precision is similar to that of Kai membranes; moreover, the membrane modules have high mechanical strength, and they should not be easily damaged if operated properly. 4. The membrane flux is high, reaching 800 l/m2*h.