52results about How to "No recycling issues" patented technology

The invention relates to a circulation gas extractive rectification technology for extracting EPA and DHA from fish oil. The method is characterized in that the fish oil is pre-heat, is introduced into a rectifying tower and rectified under extractive rectification of inert gas circulation gas to obtain a mixture of EPA and DHA. The method employs light component of the inert gas circulation gas, and employs a backflow mode for high purity separating of the components, rectification and gas stripping are fusion during a whole process, the difference of the components volatility in the fish oil can be used, so that multitime partial vaporization and partial condensation can be carried out, the light component of the hot inert gas is used, partial pressure of the light component is reduced, the light component is developed to vaporization, and the light component content in a heavy phase is reduced. In the invention, high vacuum is not required, one time purification can be used for increasing the EPA and DHA content to more than 70%.

The invention relates to a method for separating dimethyl carbonate methanol azeotrope through melt crystallization and application thereof. The method specifically comprises the following steps: introducing a dimethyl carbonate methanol azeotrope with the dimethyl carbonate content of 25-35% into a melt crystallization device, separating out dimethyl carbonate in a crystal form through cooling, then partially melting dimethyl carbonate crystals through heating sweating, removing impurities contained in the crystallization process, further purifying dimethyl carbonate, and finally obtaining ahigh-purity dimethyl carbonate product and a low-concentration crystallization mother solution. The crystallization temperature of dimethyl carbonate in a self-azeotropic system is -20 to -40 DEG C, and the operation equilibrium temperature of a crystallization section is -50 to -60 DEG C, the purity of the dimethyl carbonate product is 99.9%-99.999%, and the concentration of the crystallization mother solution is 5%-15%. The method can be used for separation and purification of dimethyl carbonate methanol azeotropic composition in the process of producing dimethyl carbonate by a synthesis method or producing dimethyl carbonate as a byproduct in the coal-to-ethylene glycol process, and has the advantages of low energy consumption, high product purity and the like compared with traditionalseparation modes such as pressurized distillation, extractive distillation or azeotropic distillation.

The invention relates to the preparation method of 2,3-dichlor-1,4-naphthaquinones, which comprises, (1) charging sodium-1-naphthylamine-4-sulfonate into water, adjusting pH to 2-5 by charging acid, (2) charging 1-10% of iron powder, zinc powder, ferric salt, ferrous salt or zinc salt, (3) letting in chlorine, (4) cooling down the reaction product at normal temperature, filtering to obtain 2,3-dichloro-1,4-naphthaquinone crude product, finally recrystallizing with organic solvents to obtain product with the content higher than 98.5%.

The invention provides a process for directly preparing trisodium phosphate by using a glyphosate mother solution, which aims at effectively recovering a phosphor resource in a mother solution to prepare trisodium phosphate. The preparation process is characterized in that after the glyphosate mother solution is subjected to catalysis and air oxidation, organophosphorus in the mother solution is oxidized into orthophosphate ions, then sodium hydroxide or soda is added into the mother solution to regulate the pH value to 9-10, the temperature is lowered to minus 5 DEG C to 8 DEG C under the condition of agitating to achieve crystallization, and separation, washing and drying are performed, as a result, the trisodium phosphate is obtained. The preparation process is simple and easy to achieve industrial application, the obtained trisodium phosphate is widely used, besides, difficulty in meeting the drainage standard of the terminal treatment of the glyphosate mother solution is lowered, and further the treatment of solid waste is reduced.

The invention provides a method for plating iron and removing arsenic for a regional aquifer. The method comprises the following steps: selecting a target regional aquifer, determining the depth, osmotic coefficient, underwater flow velocity and dispersion coefficient of the target aquifer, arranging a central pumping well at the center of the target region, defining the 5m regions around the central pumping well as a working regions, arranging four injection wells at the boundaries of the working regions, arranging a water pump in the central pumping well to pump water, respectively injecting a ferrous reagent into the target aquifer in the four injection wells by adopting an injection pump, injecting a sodium hydrochloride reagent into the target aquifer in the four injection wells by adopting the injection pump, and then injecting water to completely push the sodium hydrochloride reagent into the target aquifer. According to the method for plating iron and removing arsenic for the regional aquifer, the deficiencies in the background technology can be solved, and the method for removing arsenic can fulfill the purposes of obviously improving the arsenic removal effect and lowering the arsenic removal cost.

A method for preparing chitosan oligosaccharides through semi-wet method microwave treatment relates to a production method of chitosan oligosaccharides. The method comprises the following steps: using chitosan gelatine powder as raw material to perform hydration and microwave treatment, dissolving in water, neutralizing, and performing membrane separation, drying and the like to prepare chitosanoligosaccharides. The method does not consume organic solvent, thus the problem of recycling solvent does not exist and the pollution is low; and as the volume of the reaction system is from 1 / 3 to 1 / 5 of that of the solution method, the production efficiency is obivously increased. The method adopts microwave treatment to promote the polysaccharide degradation reaction, thus the heating effect is greatly increased. The radiation thermal effect of microwave and the non-thermal effect of microwave are utilized to prepare the product. Meanwhile, microwave is an efficient and clean energy, thus the speed of the chemical reaction can be greatly increased. The method also adopts the membrane separation mean, thus the refining efficiency is high and the product quality is controllable.