A series of Ni₂P-modified MoS₂/γ-Al₂O₃ catalysts with constant Mo contents were prepared by the thermal decomposition of ammonium tetrathiomolybdate and nickel hypophosphite under N₂ atmosphere.The structure of the catalysts was characterized by N₂ adsorption-desorption, X-ray diffraction, and high-resolution transmission electron microscopy.The catalytic performance of the catalysts for hydrodesulfurization(HDS)was evaluated in a fixed-bed microreactor using dibenzothiophene(DBT)as the model compound.The results indicated that when the amount of Ni₂P was 4%（mass）, the catalyst showed a relatively high catalytic activity with a strong preference for the hydrogenation desulfurization(HYD)pathway.Its hydrogenation selectivity(2.11)was 2.9 times that of reference catalyst(0.72)at 300℃.The addition of Ni₂P had an effect on the average stacking number and slab length of MoS₂.

An approach was proposed to determine the solubility of pure zinc lactate at a high heating rate(20 K·h^-1), which significantly improves the efficiency of solubility measurement.The results showed a good agreement with the solubility data obtained through isothermal processes.This approach was extended to measure the solubility of zinc lactate in the presence of small amount of impurity.The influences of impurities, including malic acid, succinic acid and sodium oxalate, on the primary nucleation kinetics of zinc lactate in cooling crystallization were investigated, and a method was presented to estimate the primary nucleation kinetics based on Nyvlt theory by measuring the metastable zone width of zinc lactate at specific cooling rate in the solution.The results showed that the rate of primary nucleation of zinc lactate decreased in the presence of malic acid or succinic acid.However, when sodium oxalate was introduced in the solution, the nucleation of zinc lactate was accelerated at low supersaturation but suppressed at high supersaturation.

Based on the computational fluid dynamics(CFD)method, a coupled simulation of combustion with heat transfer in the firebox radiation section and cracking reaction of naphtha in the reactor tube was carried out in a SL-Ⅱ industrial ethylene pyrolyzer by using CFX software.The standard k-ε turbulence model, eddy dissipation/finite rate chemistry combustion model(EDM/FRC)and discrete transfer(DT)radiation model, combined with multi-grey gas model for radiation properties of flue gas, were used to model the firebox.The molecular reactions model scheme proposed by Kumar was used to simulate cracking reaction of naphtha in the tubular reactor.Meanwhile, the Navier-Stokes equation system was solved by a so-called fully implicit coupled algorithm.Simulation results agreed very well with industrial data, which proved the reliability of the model.Simulation results showed that propylene and butylene yields firstly increased and then decreased, while methane and ethylene yields increased all the way.the addition of side burners brought the outlet tube skin temperature distribution to be more uniform.The flue gas recirculation made the temperature in the middle of firebox more uniform.The asymmetrical structure of the furnace led to the asymmetry of flue gas velocity at the top of the furnace, and further led to a lower efficiency of heat supply of the side burners on the rear wall than the ones on the front wall.The results could be helpful for engineers to design and optimize the  ethylene pyrolyzer.

A controllable bypass optimal design method is presented.The way to establish a heat exchanger networks(HEN)model was derived for the quantitative analysis of relative gain array(RGA).From the point of view of controllability, a HEN non-square RGA(ns-RGA)was calculated iteratively, and then the optimal bypass location was determined to ensure a more controllable HEN.Generically, RGA was used to select appropriate manipulated variables for target temperatures, but it was a breakthrough here and a novel optimal bypass location method was presented by iteratively calculating the HEN ns-RGA.Some guidelines were given to simplify the work.A case analysis indicated that changes of normal operation state of the HEN would not impact the bypasses location, which was derived from the above method.This method was adaptable to complex HEN, and could guarantee a more controllable HEN for production.A case study demonstrated the effectiveness and feasibility of the method proposed in this paper.

During the operation of heat exchanger networks(HEN)with varying operating conditions,bypass optimal control is considered an effective method to adjust outlet fluid temperature and save energy.However, locations of bypasses are derived without the verification by the control theory.And, it is always very difficult to choose the location of bypasses with the trade-off between controllability and capital investments.Therefore, it is necessary to develop a method to design a HEN control structure based on the control theory.Based on structural controllability, in order to maintain all states controllable and minimize the number of bypasses, a bypass optimal design method with all states controllable(method 1)was proposed.On the other hand, when the number of bypasses was limited, to maximize controllable states an alternative bypass optimal design method with sub-controllable states(method 2)was also presented.The results indicated that with these two methods, the optimal bypass design could be derived for any requirement of controllability and capital investments.A case study of HEN before desalting in an atmospheric/vacuum distillation plant demonstrated the effectiveness of these two methods proposed in this paper.

Based on the insight that the difference between the water network involving regeneration and that involving reuse only is that there is an additional stream, the regenerated stream, in the former one, this paper presents an iterative method for designing water-using networks of single contaminant involving regeneration reuse/recycling.For the networks with a given removal ratio(RR), a reasonable regeneration concentration is obtained first.Add the regenerated stream into the network with reuse only, the network involving regeneration can be formed.Then the design of the networks involving regeneration reuse/recycling can be performed by using the design procedure proposed for the systems involving reuse only.For the networks with the given regeneration concentration, the final design can be obtained with one iteration.For the networks with a known removal ratio, the final design can be obtained with several iterations.This paper considers the targets of freshwater consumption, regenerated water flow rate, and mass load for regeneration, and all the target items can reflect the total cost of the network.A few literature examples are investigated.The structures of the designs obtained in this work are not complex compared to that reported in the literature, and the calculation of the proposed method is very simple.

According to the dynamic characteristics of industrial production process and process variables of Gaussian distribution problems, this paper proposes a new monitoring method based on Dynamic Independent Factor Analysis(DIFA).Firstly, the paper chooses suitable time lags for each variable by auto-correlation analysis to construct the augmented matrix; secondly, compresses the augmented variable matrix by Principal Component Analysis(PCA); at last, computes the parameters by the Expectation Maximization Algorithm, establishes a mixed model of adaptive Gaussian, constructs the monitoring indices including GI² and GSPE and presents the non-parametric algorithm for confidence bounds.This new monitoring method was used in an adsorption separation process and compared with the methods based on Modified Dynamic Factor Analysis(MDFA)and Independent Component Analysis(ICA), the validity and superiority were proved.

This study analyzed the Cassie state to Wenzel state transition of droplets on surfaces decorated with assemblies of cylindrical pillars arranged on a silicon wafer from the point of view of energy.The relation curve between energy barrier of state transition on the cylindrical array of different parameters and droplet size was calculated.For droplets size larger than 2 μl，two methods could be used for the transition from Cassie state to Wenzel state: increasing the droplets’ gravitational energy or maintaining constant droplets’ size and increasing the cylindrical array spacing distance.The experimental results were consistent with theoretical analysis.

Experiments were carried out to investigate the deformation of single drop in high voltage AC electric field with different types of white oil and water.The effects of electric field strength, viscosity of oil, interfacial tension and droplet diameter on the deformation of droplet were studied.With a micro high-speed camera system and image processing technology, the deformation of droplet was observed and analyzed.The results indicate that the deformation is mainly affected by electric field strength, drop diameter and interfacial tension.The eccentricity of ellipsoid drop is approximately proportional to the power of the electric field strength, N(1.7<N<2.4), and the diameter.The drop with lower interfacial tension is more prone to deform in the electric field.The effect of oil viscosity on droplet deformation is not obvious.When the deformation is small, the change of drop eccentricity is accordance with the change of Weissenberg number, but the phenomenon is different when the deformation is large.

The lubrication film thickness developed between the two faces in a mechanical seal normally ranges in size from 1 to 15 μm.Therefore the influence of the surface tension of sealing medium cannot be ignored.In this paper a study of sealing ability of a laser-textured surface mechanical seal(LST-MS)with hydrophobic surface located at the inner radius was performed.The geometrical models of hydrophobic surface with nano-columns or nano-pores were presented, and their self-sealing ability was theoretically proved.The Reynolds equation for controlling film pressure between the two faces of such a LST-MS was solved by using the finite element method.The effects of surface tension coefficients of the sealing medium on film stiffness, opening force and leakage rate were studied at different rotational speeds and sealing pressures.It was proved theoretically that such a LST-MS could get zero-leakage under specific conditions.The results showed that when the LST-MS operated at the rotational speeds lower than 100 r·min^-1 and low fluid pressure ratios lower than 2, film stiffness and opening force were kept high while leakage was substantially decreased.The film thickness fluctuation would take place due to external perturbation, but leakage would be controlled by using barrier fluids or flushing fluids with high surface tension coefficients.The width ratio of hydrophobic face to seal face was optimized in the range from 0.01 to 0.10.

Based on the optimization of culture conditions for producing 2-keto-D-gluconic acid(2-KDG)by Serratia sp.BK-98 in a Erlenmeyer flask, the factors of dissolved oxygen(DO)and pH affecting 2-KDG batch fermentation in 100 L fermenter were further optimized to be 30% and 6.0 respectively.Under the DO-stat and pH-stat batch culture conditions, 2-KDG production reached 211.2 g·L^-1.The kinetics of DO-stat and pH-stat batch fermentation were also investigated and the models for biomass, substrate consumption and product were established respectively based on the Logistic equation, Leudeking-Piret equation and Modified Leudeking-Piret equation.Curve fittings for the above models by using experimental data were performed by the non-linear least squares method with the software Origin 8.0.With the evaluated model parameters, the calculated values of the models and experimental data were in good agreement and the models could provide guidance for 2-KDG fermentation production.

Daidzein was synthesized from 1,3-dimethoxybenzene and p-methoxyphenylacetic acid using a process containing chlorination, Friedel-Crafts acylation, demethylation, cyclization and demethylation. Because of methyl protection, reactivity of hydroxy groups was reduced and the yield of Friedel-Crafts reaction reached to 93.6%.Hydrobromic acid(40%)was used as demethylation reagent, and all methyl in 4′,7-dimethoxyisoflavone molecule could be removed.The effect of process parameters such as catalyst amount, reaction temperature and molar ratio of materials were studied, and their optimal values were as follows:(1)in Friedel-Crafts reaction, the ratio of catalyst(aluminum chloride)and 1,3-dimethoxybenzene 1.1∶1, reaction temperature 25℃,(2)in demethylation, the ratio of demethylation reagent(aluminum chloride)and 2,4,4′-trimethoxydeoxybenzoin 1.1∶1,(3)in cyclization reaction, the ratio of triethyl orthoformate and 2-hydroxy-4,4′-dimethoxydeoxybenzoin 2∶1, reaction temperature 135℃,(4)in demethylation reaction of 4′,7-dimethoxyisoflavone, reaction temperature 122℃.The structure of product was characterized by ¹H NMR and MS.

The rapid pyrolysis of 3 different ranks of coals, including lignite from Inner Mongolia, bituminous from Shenfu coalfield，and anthracite from Guizhou, has been carried out in a high-frequency furnace which could sharply reduce the secondary reactions.The pyrolysis temperatures were ranged from 600℃ to 1200℃ with an interval of 100℃.The effects of coal rank and temperature on the yields of char, char-C， and pyrolysis gas, as well as the percentages of H₂, CO, CH₄，and CO₂ in the pyrolysis gas produced from the primary stage of pyrolysis were investigated.Results show that both of the yields of char and char-C increase, while the yield of pyrolysis gas decreases as the coal rank increases.The yields of char and char-C decrease, and the yield of pyrolysis gas increases with the increasing temperature.The char-C yield of lignite can reach a level lower than 50% at the temperature of 1200℃.H₂ and CO are the main components of the pyrolysis gas, while the contents of CH₄ and CO₂ are much lower.As the temperature increases, the contents of H₂ and CO increase, and the contents of CH₄ and CO₂ decrease.The contents of H₂+CO in pyrolysis gas increase with the increasing temperature.The H₂+CO contents from 3 coals are all higher than 90% at the temperature of 1200℃.The H₂/CO ratio of pyrolysis gas also increases as the temperature increases.Both the H₂+CO contents and H₂/CO ratio in pyrolysis gas from 3 coals are in the order of anthracite>lignite>bituminous.The low heating values of pyrolysis gas from all the 3 coals are higher than 11 MJ·m^-3.As the pyrolysis temperature increases, the low heating values of pyrolysis gas of bituminous and anthracite decrease, while the heating values of pyrolysis gas of lignite have a peak value at the temperature about 1000℃.

In order to utilize protein-rich bio-wastes from the process of lincomycin manufacturing,mesophilic anaerobic digestion experiments were conducted in a batch mode to evaluate the inhibitory effects of ammonia concentrations(300—4500 mg·L^-1)and lincomycin ones(0—100 mg·L^-1)on methane production by anaerobic digestion of the bio-wastes.The results show that both the concentrations of ammonia and lincomycin had significant negative correlations with the cumulated amount of methane.After 240 h of batch incubation, the 50% effective inhibitory concentrations(EC₅₀)were 1445 mg·L^-1 and 35 mg·L^-1 for ammonia and lincomycin respectively, and 27—28 mg·L^-1 for free ammonia.Furthermore, there existed lincomycin in the system at concentration of 25 mg·L^-1, the inhibitory trend and level of ammonia on anaerobic digestion were the same as that without lincomycin.Therefore, the inhibition of ammonia on anaerobic digestion is independent of lincomycin.

The characteristics of the anaerobic sludges in Anammox-EGSB bioreactors started up with anaerobic methanogenic sludge(AMS), fresh Anammox sludge(FAS)and stored Anammox sludge(SAS)were investigated respectively.It was found that Anammox-EGSB bioreactors could be started up successfully with these three kinds of seeding sludges.The performance of the bioreactor inoculated with SAS was better than that inoculated with AMS, but worse than that inoculated with FAS.After the start-up, the VSS/SS ratio, granular diameter, settling velocity and SAA of these three seeding sludges were superior to those of the initial state.The color of three seeding sludges tended to be bright red.Besides, the cell suspension showed the characteristic absorption peaks between 400 nm and 420 nm.The changes on color and the absorption spectrum of the sludges were correlated with the changes of numbers and the activity of microorganisms during the start-up.The color and absorption spectrum could be used as an indicator in the start-up of Anammox reactors.

The first level A standard of the sewage discharge for phosphorus removal could not reach when only biological method is employed, such as the traditional CAST(cyclic activated sludge technology)process that has been widely used in municipal wastewater treatment plants.A modification for the traditional CAST process was made by introducing an independent stirring phase in the main reactor zone.The modified process has been demonstrated in a full-scale wastewater treatment plant.To optimize the metabolic environment for polyphosphate bacteria and to increase its competition ability, gradually the aeration time was shortened and the anoxic stirring time extended by two stage experiment.For the modified CAST process the efficiency of phosphorus removal is 89.1%, 22% higher than non-modified CAST process, and the first level A standard of the sewage discharge could be steadily reached for the effluent TP.The results of static tests showed that the modification of process can increase the proportion of denitrifying polyphosphate accumulating organisms, and that the removal of 1 mg·L^-1 PO₄^3--P need consume of 1.67 mg·L^-1 NO₃^--N.So, the denitrifying performance was also improved, and the concentration of NH₄⁺-N and TN in effluent both could meet the first level A standard with 10.4% energy saved.

CO₂ is the most important greenhouse gas，and reducing its emission has caught wide attention.It is very important to develop CO₂ capture technology for coal-fired power plants, which account for major greenhouse gas emission in China.Using ammonia solution to absorb CO₂ from flue gas is expected to realize low cost and high efficiency. However, this technology faces a problem of escape of ammonia.This paper focuses on the problem of ammonia escape in ammonia decarburization process, through a series of experiments on NHD(polyethylene glycol dimethy ether)inhibiting effects in bubbling absorption of ammonia.The impacts of NHD and ammonia concentrations on ammonia escape were studied, and NHD inhibition mechanism of ammonia escape was analyzed.The results showed that NHD showed inhibition for ammonia escape and enhanced removal of CO₂ at the same time.The amount of escaping ammonia was reduced by 24.86% and the removal efficiency for CO₂ increased by about 10% when 5% NHD was added to decarburization solution.The results could provide reference for further research of ammonia method to capture CO₂.

Direct and indirect ozonation of p-toluene sulfonic acid(p-TSA), a typical pollutant in pharmaceutical wastewater, was studied.The results showed that at the conditions of pH 2—13, ozone flow rate 16—64 mg·min^-1 and pollutant concentration 100—5000 mg·L^-1, the degradation followed the pseudo-first-order kinetics.The higher pH and ozone flow rate, and lower concentration were, the larger reaction constants.In order to consider the relative contribution of direct and indirect oxidation a kinetic model of ozonation was set up, in which 3 k_HO2-·/k₀ was selected as kinetic parameter.The effect of pH, ozone flow rate and pollutant concentration on 3 k_HO2-·/k₀ was analyzed quantitatively, which could provide fundamental data for the application of ozonation in pharmaceutical wastewater pollution control.

A heterotrophic nitrifier with high efficiency of removing NH₄⁺-N and significant accumulation of NO₂^--N， named strain C16， was isolated from the activated sludge of a cokes wastewater treatment facility .Cells of strain C16 were Gram negative， short rods.The colonies were translucent white.It was identified as Alcaligenes sp.according to its morphological and physiological properties and the analysis of its 16S rRNA gene sequence.Results show that all NH₄⁺-N have been removed.The removal rate of NH₄⁺-N by this strain is 94.7% and the accumulation of NO₂^--N is tremendous in the optimization medium after 4 d cultivation through the experiment of medium optimization.The concentration of NO₂^--N is up to 30.1 mg·L^-1 compared with the counterpart original cultivation which is just 7.34 mg·L^-1.

To examine the stability of carrier anaerobic baffled reactor(CABR)treating low concentration domestic sewage, the macroscopic performance, catabolic intermediate and microbial activities of CABR were investigated at different hydraulic retention times(HRTs)and different temperatures.The results showed that: ① The change from “L” shape to “\” shape of the TCOD removal curve throughout the reactor suggested qualitatively the decline of shock resistance potential, and the invariability of volumetric removal rate with increasing shock load indicated quantitatively the shortage of buffer capacity.② The increase of the ratio of soluble microbial products(SMP)/ soluble chemical oxygen demand(SCOD)along the flow-direction and the ratio of volatile fatty acid(VFA)/alkalinity less than 0.11 implied excellent potential of shock resistance.③ The decline of shock resistance could be indicated by the decrease of microbial activities.It was also demonstrated that CABR showed the best shock resistance potential at 28℃ but the worst potential at 10℃.The stability of CABR under short-term hydraulic shock load declined as temperature decreased.

Using cheap river sands as packing material and applying ozone non- continuous aeration, Mn²⁺ in raw water was oxidized into insoluble compounds that attached to sand surface and formed activated membrane having ability to remove manganese.The activated membrane became mature within only five days under the experimental conditions: ozone aeration four times a day, 10 min each time at 50ml·min^-1.The concentration of Mn²⁺ in effluent could be lower than 0.1 mg·L^-1.The maturity period of the filter for manganese removal was significantly reduced.The optimum operation condition for the mature filter was also explored.The results indicated that the filter surface membrane could maintain efficiency for a long time at the following conditions: manganese concentration in raw water 1.5 mg·L^-1, pH higher than 7.0, dissolved oxygen concentration more than 6.5 mg·L^-1 and water flow rate less than 0.6 m·h^-1.

The polyaluminium chloride(PAC)waste residue produced by a company in Hubei province is viscous and colloidal, and of weak acidity and large moisture.If it was piled or landfilled directly, environment would be polluted.The experimental investigation was carried out for treatment and utilization of the waste.Two ways were proposed for modification and utilization of the waste.One is to be used as building materials in stead of part cement to produce fired common brick;the other is to be used as additive of decolorant for refinement of petrochemical.The results show that the acidic mud with pungent swell can be changed to near neutral or neutral，and become odorless, non-toxic and environment-friendly by adding 2% of calcium lime.When the adding amount for modifying waste is within 10%—20%，the fired bricks with it could reach the requirements of the national standard and calcination temperature did reduce about 50—100℃.The modified waste could be used as additive of decolorant. When the ratio of waste/base material was in the range of （1∶9）—（2∶8）, not only the cost of deodorant could be decreased but also the influence on its two main indexes decolorizing ability and surface area was little and its performance could meet the product requirement.

The petroleum contamination in soil is another pollution problem following pesticide and heavy metal in recent years.Petroleum is a kind of compound composed of alkane, cyclane and aromatics, which has the potentiality leading to cancer, deformity and mutation.The cleaning efficiency is poor in purifying natural acidic mixture consisting of crude oil and soil by routine measures, whereas sonochemical treatment has previously been shown to be an effective method to remediate soils contaminated with hydrocarbons. Sonochemical process is carried out in this research, which remediates the experimental beach fine soil contaminated with heavy oil.The effect of factors such as: slurry concentration,duration time of irradiation,slurry pH,alkaline additive and free radical reagent H₂O₂ on the desorption of hydrocarbon from fine salty soil, is considered.And it is proposed that solid-to-liquid mass ratio is 6∶1, working solution temperature is 20℃, irradiation time is 5 min, working solution pH is 9, alkali dosing of Na₂CO₃ is 0.15% at the time of using sonochemical process technique decontaminating  petroleum  hydrocarbon- contaminated fine soil of beach.In addition, it is crucial for soil processing that some essential step should be taken to eliminate the concretion, which could assist the technique with an ideal final effect.

In the filling stage of plastic injection molding, the energy equation is dominated by convection.The simulation of temperature with the classical Galerkin finite element method in a fixed element might be unstable and oscillatory if time step is unreasonable.To get the reliable solution, the algorithm must deal with both convection and conduction, which requires highly different time scales.For this reason, the energy equation was solved by an operator-splitting method. First, the convective part of the problem was solved, and then the conduction term and source term were solved.In this way, particularly effective numerical schemes were used.As this approach used sub-time steps for the convection term, which was much smaller than that for the conduction term, the unstable result caused by convection could be solved consequently.In addition, the lumped mass heat capacity matrix was used to deal with the transient item, which reduced non-physical oscillations that the consistent mass heat capacity matrix possibly led to.For the given examples, the simulation results illustrated that the scheme in this paper had better accuracy.

After antimony doped tin oxide(ATO)precursors were prepared by the sol-gel method, oven drying, microwave drying, vacuuming drying and supercritical fluid drying(SCFD)were used to treat the alcogels of ATO precursors.Weakly agglomerated nano-sized ATO particles with tetragonal phase structure were obtained after dry precursors were annealed at 600℃ under atmosphere.The nanoparticles were characterized by X-ray diffraction(XRD), field emission scanning electron microscopy(FESEM), transmission electron microscopy(TEM)and Malvern Zen1600 Zeta sizer.The results showed that ATO particles with tetragonal phase structure were all well crystallized from four drying processes.However, only the ATO powder prepared by SCFD consisted of primary particles weakly attached to each other, and the average size was around 25 nm.The mechanism was that the particles of precursors could keep loose morphology after treatment by SCFD, which was the key to preparing weekly agglomerated nano-sized ATO particles.In conclusion, it was an effective way to avoid the nano-sized ATO agglomeration by SCFD process in the sol-gel method.

EPDM foam filled with nano-SiO₂ was prepared by the radiation chemistry method, and such material was processed by post radiation crosslinking.SEM results indicated that the content of nano-SiO₂ was a key factor in microporous EPDM foam.After adding nano-SiO₂, the pore distribution became good and the cell diameter decreased.The cell diameter was only 13 μm when SiO₂ content was 30 phr.With increasing nano-SiO₂ content，tensile strength was improved, and elongation at break increased first and then decreased.There was a maximum value when nano-SiO₂ content was 30 phr.Through post radiation crosslinking, tensile strength and elongation of microporous EPDM became obviously better than that without post radiation crosslinking.

Most of oxygen-bearing coal-bed methane(CBM)has not been utilized due to the limit in technique for production.The discharged gas leads to not only the waste of resources but also environmental pollution.In this study, a liquefaction process is proposed and designed for the typical CBM.HYSYS software is adopted to simulate the process.The flammability limits are analyzed and calculated based on the flammability limit theory and the simulated results of HYSYS.The results indicate that no flammable hazards exist in the processes of compression, liquefaction and throttling but they may appear at the top of the distillation tower.A method, in which oxygen is first removed from the feed gas with the control of the bottom flowrate(flowrate of the liquid product at column bottom), is adopted to ensure that the methane content is always higher than the flammability limit in the whole liquefaction and distillation processes, so that the operation safety of the whole process is very high.The methane recovery rate and the purity of liquid product are high with low energy consumption.Furthermore, the liquefaction process has good applicability for other gas resources.The simulation results can offer references for the separation of oxygen from CBM and security analysis of liquefied process.