Study On Mechanism And Technology Of Wastewater Treatment Based On Hydrate Method

With the rapid growth of the population,the demand for water increases sharply,resulting in the increase of sewage discharge.The shortage of water resources and water pollution has become a common problem faced by all countries in the world.Water resources have become an important factor limiting the development of human society and economy.On the other hand,with the increasingly serious water pollution,the global ecological environment is also facing a huge threat.It is urgent to reduce environmental pollution and repair ecological environment through sewage treatment.Although the traditional sewage treatment technology in domestic sewage treatment has been relatively mature,but the current industrial sewage with its complex composition,high concentration characteristics has become a problem faced by the sewage treatment industry.Especially for high-concentration organic,inorganic or organic-inorganic mixed industrial wastewater,the treatment is difficult,the treatment process is cumbersome,and the treatment economic cost is high,and the treated wastewater can only be discharged up to the standard.There is an urgent need to develop new methods,new technologies and new processes for wastewater treatment with strong applicability.The treated wastewater can only meet the discharge standard.It is urgent to develop new wastewater treatment methods,technologies and processes with strong applicability.In this paper,the technology of wastewater treatment based on hydrate method is proposed.This technology uses the structural characteristics of hydrate crystals and the characteristic that only specific guest molecules can enter the clathrate framework composed of water molecules during the formation of hydrates for sewage treatment.Constructed an MRI visualization system and a macroscopic sewage treatment experimental system,combined with molecular dynamics simulations,carried out related research on the mechanism of the microscopic exclusivity effect of hydrates in the treatment of sewage and the crystal mechanism.Using the macro-experimental system,the factors such as the addition ratio of hydrate agent,the length of sewage treatment,and the concentration of initial pollutants were studied,and the hydrate method was used to treat high-concentration organic sewage.The experimental results show that the molecular dynamics simulation proves the exclusive effect in the hydrate growth process at the molecular level,and the MRI visualization system proves the existence of the exclusive effect and solute diffusion process in the hydrate formation process in the simulated organic wastewater from the microscopic perspective;the PXRD crystal structure analysis also proves that the pollutants have no effect on the hydrate crystal structure The feasibility of applying hydrate method to wastewater treatment is proved from microscopic mechanism.Macro experiments show that the best addition ratio is when the ratio of R141 b to wastewater is 1:4;the lower addition ratio can improve the removal efficiency,but the water yield is reduced,which affects the rate of wastewater treatment.With the extension of wastewater treatment time,the growth of hydrate increases.Although the water yield and enrichment factor increase,it is not conducive to solid-liquid separation and affects the removal efficiency.The analysis of hydrate growth time shows that the best treatment time is 8-10 h.For higher initial concentration of pollutants,hydrate method can still be effective treatment,and in the experimental concentration range of 100-1000 mg / L,the initial concentration of pollutants has no effect on the removal efficiency,which proves the universality of hydrate method for wastewater treatment.The visual observation of hydrate growth process was carried out based on MRI system,and the temporal and spatial growth characteristics of hydrate were analyzed.In the process of hydrate growth,there are fast growth stage and slow growth stage.In the process of hydrate growth,liquid inclusion will be formed between hydrate crystals.The existence of liquid inclusion will affect the removal efficiency,which indicates that the growth rate and morphology of hydrate have an important impact on the efficiency of wastewater treatment.The feasibility of applying hydrate method to wastewater treatment is proved by micro and macro experiments.The treated wastewater can even get pure water under the condition of good solid-liquid separation.The hydrate based wastewater treatment technology can realize the effective treatment and recycling of wastewater,and has a good potential application prospect.