Recent research on deterministic methods for circulating cooling water systems optimization has been well developed. However, the actual operating conditions of the system are mostly variable, so the system obtained u...Recent research on deterministic methods for circulating cooling water systems optimization has been well developed. However, the actual operating conditions of the system are mostly variable, so the system obtained under deterministic conditions may not be stable and economical. This paper studies the optimization of circulating cooling water systems under uncertain circumstance. To improve the reliability of the system and reduce the water and energy consumption, the influence of different uncertain parameters is taken into consideration. The chance constrained programming method is used to build a model under uncertain conditions, where the confidence level indicates the degree of constraint violation. Probability distribution functions are used to describe the form of uncertain parameters. The objective is to minimize the total cost and obtain the optimal cooling network configuration simultaneously.An algorithm based on Monte Carlo method is proposed, and GAMS software is used to solve the mixed integer nonlinear programming model. A case is optimized to verify the validity of the model. Compared with the deterministic optimization method, the results show that when considering the different types of uncertain parameters, a system with better economy and reliability can be obtained(total cost can be reduced at least 2%).展开更多
Kathon(CMI-MI),a mixture of 5-chloro-2-methyl-4-isothiazolin-3-one(CMI)and 2-methyl-4-isothiazolin-3-one(MI),was extensively used in industry as a nonoxidizing biocide or disinfectant.However,it would show adverse eff...Kathon(CMI-MI),a mixture of 5-chloro-2-methyl-4-isothiazolin-3-one(CMI)and 2-methyl-4-isothiazolin-3-one(MI),was extensively used in industry as a nonoxidizing biocide or disinfectant.However,it would show adverse effects on aquatic life when it is discharged into surface water.In this study,the removal performance,parameter influence,degradation products and enhancement of subsequent biodegradation of CMI-MI in UV/H_(2)O_(2)system were systematically investigated.The degradation rate of CMI-MI could reach 90%under UV irradiation for 20 min when the dosage of H_(2)O_(2)was 0.3 mmol·L^(–1).The DOC(dissolved organic carbon)mineralization rate of CMI-MI could reach 35%under certain conditions([H_(2)O_(2)]=0.3 mmol·L^(–1),UV irradiation for 40 min).kobs was inversely proportional to the concentration of CMI-MI and proportional to the concentration of H_(2)O_(2).The degradation rate of CMIMI was almost unchanged in the pH range from 4 to 10.Except the presence of CO_(3)^(2-)inhibited the removal rate of CMI-MI,SO_(4)^(2-),Cl^(-),NO_(3)^(-),and NH_(4)^(+) did not interfere with the degradation of CMI-MI in the system.It was found that UV/H_(2)O_(2)system had lower energy consumption and more economic advantage compared with UV/PS system by comparing the EEO(electric energy per order)values under the same conditions.Two main organic products were identified,namely HCOOH and CH_(3)NH_(2).There’s also the formation of Cl^(-)and SO_(4)^(2-).After UV and UV/H_(2)O_(2)photolysis,the biochemical properties of CMI-MI solution were obviously improved,especially the UV/H_(2)O_(2)treatment effect was better,indicating that UV/H_(2)O_(2)technology is expected to combine with biotechnology to remove CMI-MI effectively and environmentally friendly from wastewater.展开更多
To identify the effect of solvents and anthracene on the purification of carbazole,the solvent crystallization of carbazole was investigated with xylene,chlorobenzene and tetrachloroethylene(TCE)as solvents under two ...To identify the effect of solvents and anthracene on the purification of carbazole,the solvent crystallization of carbazole was investigated with xylene,chlorobenzene and tetrachloroethylene(TCE)as solvents under two forced circulation cooling(FCC)modes.The co-crystalline experimental data were obtained from runs carried out at different anthracene levels between 1%(mass)and 10%(mass).The results showed that a uniform flake carbazole crystal obtained when using xylene and chlorobenzene under the FCC-1 mode with gradual cooling rate.Nevertheless,fine flake crystals grown under shock cooling of FCC-2 mode.It is beneficial to improving the purity of carbazole with chlorobenzene as solvent under cooling mode of FCC-1.Anthracene could promote the growth of carbazole in solution,and it has a significant influence on the purification of carbazole.展开更多
基金Financial support from the National Natural Science Foundation of China (22022816, 22078358)。
文摘Recent research on deterministic methods for circulating cooling water systems optimization has been well developed. However, the actual operating conditions of the system are mostly variable, so the system obtained under deterministic conditions may not be stable and economical. This paper studies the optimization of circulating cooling water systems under uncertain circumstance. To improve the reliability of the system and reduce the water and energy consumption, the influence of different uncertain parameters is taken into consideration. The chance constrained programming method is used to build a model under uncertain conditions, where the confidence level indicates the degree of constraint violation. Probability distribution functions are used to describe the form of uncertain parameters. The objective is to minimize the total cost and obtain the optimal cooling network configuration simultaneously.An algorithm based on Monte Carlo method is proposed, and GAMS software is used to solve the mixed integer nonlinear programming model. A case is optimized to verify the validity of the model. Compared with the deterministic optimization method, the results show that when considering the different types of uncertain parameters, a system with better economy and reliability can be obtained(total cost can be reduced at least 2%).
基金support of experimental Instrument Platform of Shandong Taihe Water Treatment Technology Co.,LTD.
文摘Kathon(CMI-MI),a mixture of 5-chloro-2-methyl-4-isothiazolin-3-one(CMI)and 2-methyl-4-isothiazolin-3-one(MI),was extensively used in industry as a nonoxidizing biocide or disinfectant.However,it would show adverse effects on aquatic life when it is discharged into surface water.In this study,the removal performance,parameter influence,degradation products and enhancement of subsequent biodegradation of CMI-MI in UV/H_(2)O_(2)system were systematically investigated.The degradation rate of CMI-MI could reach 90%under UV irradiation for 20 min when the dosage of H_(2)O_(2)was 0.3 mmol·L^(–1).The DOC(dissolved organic carbon)mineralization rate of CMI-MI could reach 35%under certain conditions([H_(2)O_(2)]=0.3 mmol·L^(–1),UV irradiation for 40 min).kobs was inversely proportional to the concentration of CMI-MI and proportional to the concentration of H_(2)O_(2).The degradation rate of CMIMI was almost unchanged in the pH range from 4 to 10.Except the presence of CO_(3)^(2-)inhibited the removal rate of CMI-MI,SO_(4)^(2-),Cl^(-),NO_(3)^(-),and NH_(4)^(+) did not interfere with the degradation of CMI-MI in the system.It was found that UV/H_(2)O_(2)system had lower energy consumption and more economic advantage compared with UV/PS system by comparing the EEO(electric energy per order)values under the same conditions.Two main organic products were identified,namely HCOOH and CH_(3)NH_(2).There’s also the formation of Cl^(-)and SO_(4)^(2-).After UV and UV/H_(2)O_(2)photolysis,the biochemical properties of CMI-MI solution were obviously improved,especially the UV/H_(2)O_(2)treatment effect was better,indicating that UV/H_(2)O_(2)technology is expected to combine with biotechnology to remove CMI-MI effectively and environmentally friendly from wastewater.
基金supported by the National Natural Science Foundation of China(21776192,22038008)。
文摘To identify the effect of solvents and anthracene on the purification of carbazole,the solvent crystallization of carbazole was investigated with xylene,chlorobenzene and tetrachloroethylene(TCE)as solvents under two forced circulation cooling(FCC)modes.The co-crystalline experimental data were obtained from runs carried out at different anthracene levels between 1%(mass)and 10%(mass).The results showed that a uniform flake carbazole crystal obtained when using xylene and chlorobenzene under the FCC-1 mode with gradual cooling rate.Nevertheless,fine flake crystals grown under shock cooling of FCC-2 mode.It is beneficial to improving the purity of carbazole with chlorobenzene as solvent under cooling mode of FCC-1.Anthracene could promote the growth of carbazole in solution,and it has a significant influence on the purification of carbazole.
