Henan YinZhidu Environmental Protection Technology Co., Ltd. Desulfurization and Decyanation Treatment Technology

As an influential manufacturer and exporter of thiocyanate products in China, our company has studied and innovated the environmental protection treatment technology of coke oven gas desulfurization and decyanation waste liquid by combining years of technological innovation results and production experience.

Since 2019, it has cooperated with large coking enterprises such as Shiheng Special Steel, Hua'an Coking, Linhuan Coking, Laigang Coking, Henan Liyuan Coking and other large coking enterprises to deal with coking desulfurization and decyanation waste liquid. At present, the device is running stably and the quality of salt products is excellent, which has a demonstration effect in the industry. On this basis, through further technical research and development, our company has designed and established a series of processes, equipment, product quality, investment plans, etc. that can meet the basic environmental protection requirements to the high standard of comprehensive utilization of waste liquid.

The technology of Henan YinZhidu Environmental Protection Technology Co., Ltd. is suitable for environmental protection treatment of desulfurization and decyanation waste liquid produced by HPF method with ammonia as absorption medium, A.D.A method with sodium carbonate as absorption medium and vacuum potassium carbonate method with potassium carbonate as absorption medium.

　　key technology

1, waste liquid treatment using the company's patented technology and proprietary technology, the oxidation of thiosulfate into sulfate, the whole process can not produce thiosulfate, salt products for sulfate and thiocyanate.

Efficient and reliable comprehensive energy-saving technology; energy consumption level is lower than 10%-20% of the energy consumption required for the treatment of waste liquid by existing separation technology;

3. Completely solve the comprehensive technology of high-efficiency water treatment and waste liquid treatment and process environmental protection technology for waste water recycling, and add industrial tail gas absorption device. The normal operation of the whole system does not produce secondary pollution and "zero" discharge to the environment. After the salt-containing waste liquid is treated, 30% of the condensate water produced by the reverse osmosis membrane meets the requirements of the supplementary water of the desulfurization system and is recycled to the desulfurization system, 70% clear liquid direct discharge or cooling circulating water requirements.

4. Professional equipment, engineering anti-corrosion integrated technology and efficient automation technology.

5, Proprietary technology and process quality control technology to ensure product quality in the process of salt extraction.

　　Comparison of technical solutions

1. The existing traditional salt extraction process meets the basic environmental protection requirements. According to the three-phase phase diagram, physical separation method is adopted, but the separation process is complicated and the separation is not complete. The salt extraction products are thiocyanate and mixed salt (mixture of thiosulfate, ammonium sulfate and thiocyanate). After salt extraction, the wastewater needs to be further treated or returned to the desulfurization system.

2. This technology meets the requirements of high standards of environmental protection. It adopts a combination of physics and chemistry to convert waste liquid from three salts into two salts. The salt-extracting waste liquid is further separated and purified through reverse osmosis membrane. 70% of the waste liquid meets the requirements of direct discharge standard or cooling circulating water, and the remaining 30% is returned to the desulfurization system for use as supplementary water.

The salt extraction products are high quality thiocyanate, ammonium sulfate, and thiosulfate-free products.

The specific technical indicators are as follows:(HPF method, A.D.A method direct salt extraction).

　　Comparison of salt extraction from desulfurization waste liquid and acid production by concentration of desulfurization waste liquid

1, the investment cost is high, the treatment of the same amount of wastewater needs to invest more than twice as much as salt.

2, the risk is high, because sulfuric acid is a high risk, easy to produce dangerous chemicals. From production to transportation management is very strict, prone to accidents, project procedures and its complexity is not easy to approve.

3, the area is large, most coking enterprises at the beginning of the civil planning did not design excess space, acid process required equipment and floor area is much larger than the salt process.

4. The operating cost is too high. Assuming that the production cost for salt extraction from one ton of waste liquid is 400 yuan, the cost for acid production will be 600-800 yuan. Moreover, due to the oversupply in the market, it is not easy to sell, and subsidy money is usually required to sell.

5, acid process is not mature at present, our company has many years of desulfurization waste liquid salt extraction mature technology and experience.

Considering the advantages of salt extraction from desulfurization waste liquid is higher than that of concentrated acid from desulfurization waste liquid.

　　Disadvantages of desulfurization liquid treated by pre-oxidation

1, the equipment is not matched, need to add a large number of equipment, and the volume is large, the site is not matched.

2, the early oxidation of large investment funds, high operating costs.

3, the product quality is not high in the late oxidation quality.

4, the installation and construction process cross, affecting the normal production of the existing workshop.

　　Advantages of post-oxidation

The equipment investment is less, the occupied space is less, the quality of the produced products is much higher than that of the former oxidation, the construction process is avoided, and the safety factor is high.

　　Process characteristics and technical advantages

The salt extraction process of desulfurization waste liquid developed by Henan YinZhidu Environmental Protection Technology Co., Ltd. has the following characteristics:

1. The process is streamlined, the operation is convenient and simple, easy for workers to master and operate, and easy for production management. Savings on investment.

2. The product has high purity, good quality, good sales and fast return on investment.

3, desulfurization waste liquid treatment application company's unique technology, ammonium thiosulfate into ammonium sulfate, nitrogen content of not less than 20.5, the final product does not produce thiosulfate.

4, sulfur oxidation using slow release oxidant, no corrosion to the equipment, simple operation, high safety factor, to avoid the addition of sulfuric acid and other strong oxidants, instantaneous oxidation of equipment, workers operating caused by unpredictable hazards, but also to avoid yellowing and other defects, so that the product has an absolute quality advantage in the market.

5, the use of unique process control technology to control the entire production process to ensure long-term stability of product quality.

6, The company has its own chemical equipment plant, which can provide professional equipment support for the desulfurization waste liquid salt extraction project to ensure the smooth progress of the project.

7, based on my company's many years of production experience and plant production equipment for many times the replacement and a number of domestic success. Our engineering and technical personnel have accumulated a large amount of experience in process design and equipment layout, fully considering all details of the project, ensuring the stability and smoothness of the process. In addition, the equipment selection and material selection in the salt extraction project are accurate, and the selected equipment has a long service life and stable operation. No loss to Party A due to equipment selection failure.

8. In view of various problems that may occur in the production process, we have the ability to analyze, prevent and deal with them, so that each new project can share our accumulated rich experience and make up for the technical deficiency of desulfurization waste liquid and salt extraction in the coking plant.

9. The whole device adopts high-efficiency, energy-saving equipment and comprehensive automation technology, which greatly reduces labor intensity, reduces staffing, and saves labor costs.

10, the concept of green environmental protection into the salt extraction technology, the whole set of salt extraction device operation process, no secondary pollution, to achieve "zero" emissions. The site environment is clean and tidy, suitable for workers to work and produce.

11, the company successfully developed the rise of pipe waste heat recovery patented technology, and now has cooperated with coking enterprises to achieve industrial production. The steam produced by this technology can be used in the desulfurization waste liquid salt extraction project can greatly reduce the steam cost, improve the profit margin and shorten the investment recovery period.

12. The company has its own R & D team and laboratory, and has invested special funds, and has strong independent R & D and design capabilities. A product development mechanism of promotion generation, R & D generation and storage generation has been formed.