50results about How to "Improve mass transfer conditions" patented technology

The invention discloses an airlift reactor having a spiral porous sieve plate. The reactor includes a reaction tank body. A flow guide cylinder and a gas distributor are arranged in the reaction tank body. The gas distributor is disposed under a raising section of the flow guide cylinder. A spiral porous sieve plate is arranged in the raising section of the flow guide cylinder. The body of the spiral porous sieve plate is in a spirally raising shape, so that a part of two / three-phased flow in the raising section is guided. There are a plurality of sieve pores in the body of the spiral porous sieve plate, so that the rest of the two / three-phased flow in the raising section is subjected to flow guiding and bubble breaking. The airlift reactor considers both macroscope mixing and microscope mixing, wherein the liquid is driven by ejected gas to flow cyclically, so that raising large bubbles are broken into small bubbles. The reactor can effectively inhibit aggregation of bubbles, increases gas holdup, and increases volume mass transfer coefficient.

The invention discloses a method for preparation of 2, 5-dichloronitrobenzene by continuous nitration. The method comprises the steps of: adopting three-stage kettle type continuous reaction, adding sulfuric acid, nitric acid and p-dichlorobenzene in an extraction kettle into a first stage nitrification kettle simultaneously to carry out nitrification reaction, letting nitrification liquid enter a next stage nitrification kettle through self-carried raisers of all nitrification kettles in order to react, at the end of reaction in a third stage nitrification kettle, separating an oil phase and an acid phase, carrying out neutralization, washing and dehydration on the oil phase so as to obtain 2, 5-dichloronitrobenzene, internally recycling part of waste acid in the acid phase back to the first stage nitrification kettle, letting the residual waste acid enter an extraction kettle, and performing p-dichlorobenzene extraction, and then conducting separation to obtain acidic p-dichlorobenzene and extracted waste acid, concentrating the extracted waste acid into concentrated sulfuric acid, and making the concentrated sulfuric acid and acidic p-dichlorobenzene enter the first stage nitrification kettle for recycling. The method provided by the invention adopts automation control, cancels a mixed acid preparation procedure, simplifies the technological process, can realize continuous nitrification reaction, continuous nitrification liquid separation and continuous waste acid extraction.

The invention provides an artificial board wastewater treatment system and technology. The artificial board wastewater treatment system comprises a physical-chemical separating tank, a water collecting and regulating tank, an air flotation reaction tank, a water distributing trough, an anaerobic fluidization bed, a hydrolysis fluidization bed, an aerobic fluidization bed, a coagulation reaction tank, a micro-filtering device, an O3 oxidation column, a clear water tank and an accident tank, wherein the machine is characterized in that three grade biological fluidization beds of the anaerobic fluidization bed, the hydrolysis fluidization bed and the aerobic fluidization bed are combined to perform biological wastewater treatment. Compared with the conventional artificial board wastewater treatment technology by using a fixing bed and an activated sludge system, the machine disclosed by the invention is adopted for treating artificial board waste water by designing the technological parameters of relevant working procedures, and the machine has unique advantages in the aspects of treating organic waste water which is high in concentration and difficult to degrade. Key equipment of the system is small in volume, the whole system has stronger resistance to impact load, the sludge is sufficiently degraded, and the problem of sludge bulking is solved.