Decolorization and reuse of by-product waste sulfuric acid
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The company produces dilute sulfuric acid as a by-product, with an annual output of around 10,000 tons. Its COD level is between 6,000 and 8,000; it contains 2% nitric acid, the sulfuric acid concentration is about 30%, and the color is bright red. The aim is to remove this color and to reuse the acid after reducing its COD level. Individuals and enterprises with appropriate technologies are welcome to get in touch.
Hello, we specialize in this area and would like to discuss it with you
The Research Institute of Nanhua Group possesses advanced processes and complete sets of technologies for the pyrolysis of waste acid to produce acid, which have been applied in over 20 facilities across China. It also has technologies for the concentration and recycling of waste acid. The former approach is suitable for large state-owned enterprises, as it requires significant investment; however, the waste acid produced after treatment meets national standards, and the operating costs are somewhat higher； The latter requires less investment, but the treated waste acid contains a small amount of impurities, with a purity level of up to 98%. For the concentration of waste acid, our company has a recycling facility with an annual capacity of 120,000 tons; the main equipment can be used for over 15 years. The contact number is 13815444545. We have also designed multiple systems for handling waste acid in China’s dye industry, ranging from pilot-scale to pilot plant scale and up to industrial production scale
We use macroporous adsorption resins to absorb organic substances; they are resistant to strong acids, strong bases, and strong organic solvents. I can send you samples for you to try out, or you can contact me at 17691174168
Macroporous resin was tried, with average results.
Hello! Could you give a brief overview of the component groups of COD? If COD is a low-boiling substance, and with 2% nitric acid present, it should be feasible to recover a concentration of over 93%. Nitric acid has a washing effect on sulfuric acid; however, the color of the recovered sulfuric acid is uncertain. It is best to provide water samples and conduct experiments or pilot tests.
This post was last edited by *a*ebing on 2020-7-21 at 14:21. Acid recovery is a topic that is both complex and simple; it arises in various industries. There are many mature processes available, including extraction, concentration, and the production of by-products such as magnesium sulfate and sulfuric acid. The choice of method depends on the specific conditions of each company. For extraction, an effective extractant must be selected based on the components present in the waste acid; for concentration, it is necessary to consider whether the organic substances in the waste acid can be reused; and when producing by-products, the sales scope needs to be taken into account
We considered producing magnesium sulfate, but the added value is too low, and market demand is also an issue. Do you have any other methods for handling such cases?
It depends on the quality of your water; different industries have varying approaches. Those that generate anthraquinone wastewater use extraction methods, but the operating costs are not low. Activated carbon also has a good adsorption effect. The magnesium sulfate market is actually quite large, but most of it is exported to Southeast Asia; coastal and riverine areas could be considered for this purpose
This post was last edited by hhm122 on 2020-7-28 at 16:18. The key to realizing the value of dilute sulfuric acid lies in its recycling; this can be achieved using molecular cutting technology. The process is as follows: 1) Purchased sodium ions (containing only sodium ions and no other impurities) are reacted with dilute sulfuric acid (at a molar ratio of 2:1 between sodium ions and sulfate ions). After cooling and crystallization, followed by centrifugal separation, sodium sulfate crystals are obtained. The mother liquor is further processed to remove sodium sulfate, ensuring that its concentration remains below 50PPM. Organic substances are removed from the mother liquor through secondary or tertiary nanofiltration; these organic substances are then burned, resulting in a pure mother liquor (i.e., hydrogen ions). The sodium sulfate crystals are subjected to molecular cutting to separate sodium ions and sulfate ions. The sulfate ions combine with hydrogen ions to produce high-purity sulfuric acid for reuse, while the sodium ions can also be recycled. Detailed discussion on WeChat 13508541372