Water Consumption And Residual Alkali In The Used Silicate Sand With Three Wet Regeneration Methods

In the21st century, because of the increasingly strict requirements in costing,energy and environmental, the development trend of casting foundry industry is greencasting. Sodium silicate sand has the characteristics of inexpensive, nontoxic, tasteless,and good labor condition in the process of using. Regeneration of Sodium silicatesand is a worldwide difficult problem. If this difficult technical problem can be solved, the water glass sand will become the green sand for casting. Wet regeneration is theprimary method of sodium silicate sand regeneration. But in the process of wetregeneration process the factors restricting wet regeneration are equipment covers anarea of big, large water consumption and high energy consumption in the process ofregeneration.The wet treatment on the CO2hardening sodium silicate sand is feasible becausethe surface runoff is soluble in water. This article explored the way to reduce theoccupied area and water consumption by improving the devices and reduce the waterconsumption and alkali residue in it.Research has shown that the optimum reaction conditions is in the800r/minspeed and in the temperature of80℃and the reaction time is10min in the discuss oftaking samples by indirect method and the influencing factors of speed, temperatureand time. After the reaction by the optimum conditions, the alkali removal rate isabout75%; water consumption is500ml and achieves the sand water treatment effectthan1∶1. But this method has the shortcomings of difficulty operation and sampling,time-consuming. We need to improve process and equipment. Improved hot watertreatment method needs less time, the operation is simple and the equipment is simpletoo. In hot water treatment, the higher the temperature of the hot water, the higher the removal rate of the alkali, and the wet regeneration can be better. The mostappropriate temperature of80℃considering the factor of economy, energyconsumption. By using this method the alkali removal rate as78%, waterconsumption was500ml and sand water ratio1∶1. But hot water treatment methodin the process can produce bubble, the drilling mud cuttings were not been dealbecause of the bubble, this lead to more water and alkali residue in the process. Inorder to reduce the amount of air bubbles during the processing of produce, we adoptthe steam treatment. In the steam treatment, different temperature of the steamtreatment has different effects. The alkali removal rate was85%, water consumptionwas300ml, water ratio of1∶0.6by using the steam treatment method, which greatlyreduced the water consumption and improved the removal rate of the alkali in theprocess. And this method has the advantages of short processing, high efficiency, lessdust and less renewable liquid. It also has no noise pollution. But in the process ofsteam treatment still produce a small amount of bubbles and the steam energyconsumption is higher than the hot water. Analyzed three different wet regenerationtreatments, steam treatment is the CO2hardening sodium silicate sand wetregeneration method we consider the conclusion of the direction.