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This article is a study conducted for the Baotou Rare Earth chloride wastewater treatment and resource. The rare earth chloride wastewater is generated in the production process of single rare earth carbonate, including the mother liquor and water washings. Most enterprises have a high concentration of the mother liquor evaporation and crystallization, the production of chloride chemical products. But water lotion concentration is low, the large amount of water, if the direct evaporative crystallization, high energy consumption enterprises bear. The subject of a rare earth plant in Baotou City chloride wastewater emissions as the research object, using the air blowing off and sodium zeolite adsorption combined of washing wastewater ammonia removal. The main topic is divided into two parts of the stripping the experimental and sodium zeolite adsorption experiments. The stripping experiments including single factor and orthogonal two experimental part. Single factor experiment to determine the impact of stripping efficiency four main factors - temperature, pH, gas-liquid ratio and stripping time parameter values. By orthogonal experiment: factors affect the efficiency of the rare earth ammonia wastewater stripping primary and secondary order: pH value gt; temperature gt; stripping time gt; gas-liquid ratio, pH = 11.0, stripping temperature = 40 ° C, blowing off time = 3.5h, gas-liquid ratio = 5000 experimental conditions, the stripping process, the ammonia content of rare earth chloride wastewater by 10025.70mg / L reduced to 230.59mg / L, the removal rate was 97.70%, blowing prolapse of ammonia gas available sulfuric acid absorption, made ammonium sulfate recycling. Sodium-type zeolite adsorption experiment includes three parts: Preparation of the sodium-type zeolite, the adsorption experiment, the regeneration of the adsorbent. Through the single factor experiment to determine the three main parameters affecting the sodium zeolite adsorption, pH, zeolite dosage and adsorption time best parameter values. By orthogonal experiment: factors affecting sodium zeolite adsorption of ammonia nitrogen efficiency order was: dosage gt; adsorption time gt; pH value, pH = 7.0, dosage = 20.0 g, adsorption time was 3h Under the experimental conditions, after adsorption of ammonia nitrogen content of the wastewater from 230.59mg / L dropped to 24.15mg / L, the removal rate was 89.53%. Wastewater ammonia emissions standards. Zeolite regeneration experiments show that the the zeolite regeneration best roasting temperature of 450 ° C, roasting time of 1.5h, ammonia removal rate decreased with increasing regeneration times. The experimental study stripping and sodium zeolite adsorption combined processing of rare earth chloride wastewater provides a reliable reference for rare earth wastewater treatment.
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