| In the chemical production process,a large amount of high-salt wastewater will be produced,and the treatment of such high-salt wastewater is very difficult.At present,there are some limitations and defects in the high-salt wastewater treatment technology applied at home and abroad.Therefore,it is necessary to study a more efficient and energy-saving treatment technology for high-salt wastewater.On the basis of previous studies,the author proposes to treat high-salt wastewater by combining high-voltage electrostatic field,gas-liquid contact evaporation and multi-effect evaporation.The effects of various technologies on high-salt water treatment are studied separately.Experimental conclusions A high-voltage electrostatic field gas-liquid contact two-stage three-effect evaporation system was designed to utilize the low-quality heat energy of wastewater in the chemical production process to desalinate high-salt wastewater.The main research contents and conclusions are as follows:(1)The gas-liquid contact evaporation and concentration device was designed independently to explore the influencing factors affecting the evaporation and concentration of the system.The orthogonal experiment was designed to explore the optimal control parameters under certain working conditions.The experimental results show that the evaporation of the system increases with the increase of temperature,and the higher the temperature,the faster the growth rate;the evaporation rate increases first and then decreases with the increase of the circulation flow rate;the salinity of the raw water will be to a certain extent.The system inhibits the evaporation of the system,but its influence is minimal;the degree of influence of each factor on the system evaporation is: temperature>flow>NaCl concentration.The theoretical average value under the optimal horizontal combination condition in this experimental range is 46.04L/h.(2)Using the high-voltage electrostatic field designed by the predecessors to study the effect of high-voltage electrostatic field on high-altitude evaporation,the experimental results show that the high-voltage electrostatic field also has a steaming effect on high-salt water,and the system evaporation rate is 5kv.1.45 times under voltage conditions;and the greater the electric field strength,the greater the amount of evaporation per unit time.(3)Based on the results of the pilot test,a two-stage three-effect multi-effect evaporation device was designed to conduct on-site experimental research to investigate the evaporation concentration efficiency of the system under different initial water temperature and voltage intensity conditions.The experimental results show that the system The concentration rate increases with the increase of initial water temperature and voltage intensity.Under the experimental setting conditions,when the voltage intensity is 8KV and the initial water temperature is 61.9°C,the evaporation in the system within 1h is 1651kg/h,and the concentration rate reaches 33.02%.(4)The experimental data is used to calculate the energy consumption of the system,and compared with other thermal concentration techniques,the experimental results show that the energy consumption of the new technology under the optimal parameter setting conditions is only 8.8KW·h/t.Compared with other energy-saving high-salt treatment technologies,it can save about 50% energy consumption and reduce energy consumption by 16% compared with conventional multi-effect evaporation technology.Through the experimental research and analysis,this paper finds that the high-efficiency concentration system designed in this paper is feasible in the field of high-salt wastewater treatment,and has the characteristics of energy saving,high efficiency and good scale inhibition performance in the process of treating high-salt wastewater.The market-based application of high-efficiency evaporative concentration systems provides a technical reference. |
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