Efficient anaerobic reactor used for fuel ethanol waste water secondary anaerobic treatment

Abstract

The invention discloses an efficient anaerobic reactor used for fuel ethanol waste water secondary anaerobic treatment. The efficient anaerobic reactor is divided into a perfect mixing region, a first internal circulation region, a second internal circulation region and a solid-liquid separation region from bottom to top. An inlet water distribution pipe, a first sludge guide plate and a first gas guide plate are arranged in the perfect mixing region from bottom to top. A first internal circulation sleeve, a second gas guide plate and a first reflection cone are arranged in the first internal circulation region from bottom to top. A second internal circulation sleeve, a second sludge guide plate, a second reflecting cone, an gas collecting chamber and a marsh gas lead-out pipe which is communicated to the top of the gas collecting chamber are arranged in the second internal circulation region from bottom to top. A gas-solid separation ring plate and an overflow weir are arranged in the solid-liquid separation region from bottom to top, wherein the overflow weir is externally connected with a water draining pipe, and the lateral wall, below the gas-solid separation ring plate, of the reactor is externally connected with a gas discharging pipe. Reaction and solid-liquid separation are realized after waste water flows through the four regions from bottom to top, and a good treatment effect can be achieved.

Description

technical field [0001] The invention relates to a fuel ethanol wastewater treatment device, in particular to a high-efficiency anaerobic reactor for secondary anaerobic treatment of fuel ethanol wastewater. Background technique [0002] Fuel ethanol has the characteristics of cleanness and regeneration, which can reduce the emission of carbon monoxide and hydrocarbons in automobile exhaust. It is an important part of renewable energy. important role in increasing income. At present, the national strategic plan for the development of fuel ethanol requires "not to compete with others for food, not to compete with food for land", actively and scientifically develop non-grain fuel ethanol, insist on focusing on non-food, encourage the diversification of raw materials, and become the development trend of fuel ethanol technology. Potato starchy fuel ethanol mainly includes root starchy raw materials such as cassava and sweet potato. Because of its good processing performance, it ...

AI Technical Summary

Problems solved by technology

Potato starchy fuel ethanol mainly includes root starchy raw materials such as cassava and sweet potato. Because of its good processing performance, it has been used as an ideal substitute raw material for large-scale fuel ethanol production. In the production process of potato non-grain starchy fuel ethanol A large amount of acidic, high-temperature and high-concentration organic wastewater is produced, and 11-15 tons of process wastewater can be produced for every 1 ton of fuel ethanol produced. Large, high content of suspended solids and difficult solid-liquid separation. However, the waste water produced in the process of producing fuel ethanol from non-grain starch raw materials also faces many problems in the process of meeting the discharge standards: such as high content of suspended solids and difficult treatment , the processing cost is high, and it is difficult to apply to large-scale industrialization development, etc.

Traditional fuel ethanol wastewater is generally treated with the "first-level anaerobic + aerobic" process after solid-liquid separation, but the traditional process has high pre-treatment costs, large investment, and instability, which brings inconvenience to subsequent anaerobic treatment. It is easy to impact the system. In addition, due to the high suspended solid content of this type of wastewater, there are disadvantages in the application of high-efficiency anaerobic reactors UASB and EGSB, and there are clogging problems caused by cassava and other residues entering the treatment system. Large-scale fully mixed anaerobic reactors Fermentation is not easy to stir evenly, sludge loss problem (digested sludge is not easy to settle and recover), etc. At the same time, the viscosity of the first-stage anaerobic effluent is high, and liquid-solid separation is difficult. The volume load of the anaerobic operation of the whole waste water is usually 2.5KgCOD / m 3 About d, which affects the production of fuel ethanol and economic benefits. The traditional method needs to separate the sludge from the high-temperature anaerobic digestion solution and return it to the first-level high-temperature anaerobic tank, which greatly increases energy consumption and investment, and is not suitable for large-scale treatment systems.

At the same time, the suspended solids cannot be effectively removed before entering the secondary anaerobic reactor, and the SS content is still as high as 6000-12000 mg / , which seriously affects the continuous and efficient operation of subsequent anaerobic reactors such as UASB.

The energy (biogas) in the wastewater cannot be extracted to the maximum extent. At the same time, the ammonia nitrogen and total nitrogen cannot be effectively removed after the traditional aerobic process, and the removal rate of nitrogen and phosphorus is difficult to achieve a stable effect.

The patent "Treatment Method of Potato Non-grain Starch Fuel Ethanol Grains" discloses a method for the treatment of fuel ethanol wastewater, but in this method, the secondary anaerobic reactor adopts UASB, the gas stirring intensity is weak, and the hydrodynamics is poor , coupled with the high viscosity of water quality, resulting in poor mass transfer effect, the COD removal rate is only about 50%

Due to the lack of high-quality carbon sources in the subsequent aerobic biochemical process, the denitrification efficiency decreased

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