Method for treating H-acid production wastewater

Abstract

The invention relates to a method for treating H-acid production wastewater. The method comprises the following steps of: adding ammonia water into waste liquid until the pH value is 4 to 5 to obtain roughly treated feed liquid; heating to evaporate water in the feed liquid until the solid-to-liquid ratio is 25 to 35 percent so as to obtain supersaturated feed liquid; cooling, and crystallizing to obtain mixed feed liquid; and centrifuging to obtain an inorganic salt solid fertilizer and organic matter centrifugate. A new road is opened, water is evaporated in a distillation mode by skillfully utilizing the characteristic that organic matters and the water in the wastewater have different boiling points, organic matters and inorganic salts are separated, sticky colloidal organic matters and solid inorganic salts are separated in a centrifuging mode, the organic matters are combusted or further separated, the solid inorganic salts containing a large amount of ammonium sulfate can be directly used as a fertilizer, and waste is turned into wealth, so that the long-term technical problem that the H-acid waste liquid is difficult to treat is solved.

Description

technical field [0001] The invention relates to a treatment method for H-acid production wastewater. Background technique [0002] H-acid, also known as 1-amino-8-naphthol-3,6-disulfonic acid, colorless crystal, is an important dye intermediate, mainly used in the production of acid, reactive dyes and azo dyes, also Can be used in the pharmaceutical industry. Slightly soluble in cold water, easily soluble in hot water, soluble in alkaline solutions such as soda ash and caustic soda. Sulfuric acid (or hydrochloric acid) is added in the acid analysis process to precipitate H-acid monosodium salt, and the filtered waste liquid is a typical organic wastewater with high concentration, high chroma, and high biological toxicity. [0003] The main organic pollutants in the waste liquid are naphthalene and naphthalene derivatives, and the main inorganic substances are sodium sulfate and ammonium salts. Compared with other wastewater containing naphthalene-based organic substances, ...

AI Technical Summary

Problems solved by technology

[0007] (4) High toxicity. H acid belongs to polycyclic aromatic hydrocarbons and has strong biological toxicity. If the waste water is discharged directly without treatment, it will seriously pollute the environment and cause great harm to the human body;

The BOD of most wastewater in this type of wastewater 5 / COD is extremely low, has poor biodegradability, and is toxic to microorganisms, so it is difficult to treat with general biochemical methods

[0009] Regarding the methods for this kind of production wastewater treatment, there are mainly wet (catalytic) oxidation methods, photocatalytic oxidation methods, extraction methods (including liquid film extraction methods, complex extraction methods), etc. These methods have complex equipment, special Difficult to guarantee material quality, expensive chemicals, harsh operating conditions (such as high temperature, high pressure, etc.), high energy consumption, and secondary pollution

[0010] Aiming at the particularity and difficulty of H-acid production wastewater treatment, those skilled in the art have also carried out a series of explorations, for example: Chinese Patent Application No. 200710057544.1, provided in the patent name "a treatment method for H-acid production wastewater" It is the method of "adsorption by ion exchange resin". The Chinese application number is 200710057626.6, and the same is provided in the patent name "1-amino-8-naphthol-3,6-disulfonic acid production wastewater treatment and its recycling method". It is the method of "using ion exchange resin to adsorb"; Chinese patent application number 200510037697.0, the patent name is "method for purification and resource recycling of H acid production wastewater", and it provides "adsorption by using an adsorption tower filled with macroporous resin " method; the above method of using resin adsorption is more complicated to operate, and it is more difficult to control the nodes

Chinese patent application number 200710051622.7, patent name "adding sodium chloride method to treat H acid wastewater", provides the method of "adding a certain degree of sodium chloride, heating to volatilize hydrochloric acid, and extracting H acid and T acid"; this Heating under this method to volatilize hydrochloric acid from the liquid containing sodium salt requires a higher temperature, and it cannot be widely used in industrial production.

Chinese patent application number 200910234684.0, patent name "A Sunlight / Electricity-Fenton Chemical Treatment Method for Dye Intermediate H-Acid Wastewater", provides a method of "utilizing solar energy to generate electricity, and then electrolyzing the waste liquid", which requires Special solar power generation equipment, the cost is relatively high

Images