Based on actual running status，this paper indicated different energy-saving features and economic threshold for different heat resources of coal moisture control and quantificationally analyzed the performance of energy-saving & emission-reduction by calculating coal moisture control of fluidized bed with flue gas as heat resource and the coal moisture control of rotary kiln with steam，aiming at an optimum running of the system.
This paper studied the technique of production,current status and outlook for dimethyl ether and also put forward a suggestion for this industry,which has overproduction nowadays in China and a bright future in the long run.
The drying of low rank coal is the necessary pre-treatment process for its efficient utilization.A process of "fluidized-bed drying with internal waste heat utilization" which has been operated in commercial scale in Germany is expounded in this paper.The process with innovative concept of technology has advanteges of safety,high efficiency,low consumption and less emission.It is the advanced process suitable for pre-drying of low rank coal and worth notice.
By the means of coal\|quality analysis and crucible electric furnace coking experiments on Austrilian coal and domestic six kinds of single coal，the analysis of the feasibility of Australian coal instead of Xiqu coal for coal blending were investigated.The results indicated that the Australian coal is featured with low ash，low sulfur and high volatile content，so blending the Australian coal can decrease the ash and sulfur content，increase the anisotropic index of coke after carbonization and improve the coke strength.
The harm of CO as well as the factors effected CO content in waste gas by coke oven heating is summarized.CO content in coke oven waste gas can be reduced efficiently by technical measures such as controlling excess air factors,bettering bricklaying management of newly-built coke oven,using reversing cocks during BFG heating,adding air cleaning device during reversing,installing on\|line instruments to detect the content of the waste gas,and emphasizing routine hot maintenance for coke oven.
This paper introduces a way for on-line check of connecting duct in the quenching chamber which can directly monitor the damage of refractories in connecting duct for a better operation of CDQ chamber and with longer annual repair cycle.
Based on the properties analysis of long flame coal.We added long flame coal to replace part of 1/3 coking coal and gas coal for cokemaking test according to the present coal blending scheme.The result shows that long flame coal can replace part of 1/3 coking coal and gas coal for cokemaking when increasing the mass percentage of fat coal. This will be beneficial for reducing sulfur and ash content in coke，saving the coking coal resources and lowering the coal blending cost.
This paper discussed mean maximum reflectance of vitrinite in individual coals and analyzed pore structure of coke through 40kg test oven.The regression equation of pore structure parameters and the coke qualities can be used to guide coal blending and coking.
This paper described a pre-crushing for individual coal fineness by using 70kg testing coke oven and CDQ to determine the coal category to be pre-crushed and optimum fineness range with precondition of ensuring the hot strength of the coke.The research shows that with increasing of the coal fineness,the hot strength of the coke also varies with different fineness of lean coal and gas coal and when the fineness of crushed coal is controlled around 60%,the bulk density of the blended coal increases,which could benefit the output and quality of the coke.
This paper analyzed charging emission control status in coking industry and described a solution by using high pressure ammonia liquor plus a double-U emission transfer pipe on oven top and a dedusting hood on P.S. plus water-seal type dedusting main for suction,incineration and purification on the emission at oven ends,which has dedusting efficiency up to 95%~99%.
With description of the cause，harmfulness，mechanism and prevention measures against water hammer，and by analyzing several typical measures for water hammer prevention in wet quenching system，this paper concluded that delay\|close check valve can be selected at the outlet of quenching pump and automatic hydraulic pump can be used on the pipeline carrying quenching water so that the water hammer can be effectively avoided in the wet quenching process.
This paper introduces the influencing factors to the de-dusting efficiency of secondary de-duster and improvement measures,and some problems which need to be solved in design.Practice shows that the secondary de-duster can meet the CDQ process requirement on de-dusting.It is stable and has high performance-price ratio.
A comparison is made between the year of 2011 and 2012 for the coal ash content of charging coal as well as the ash content of self-produced coke in Shaoguan Iron & Steel Plant and an analysis is made on the effect of cost by reducing ash content in coke.The result shows that,comparing with 2011,the ash content of self-produced coke in 2012 decreases by 0.54%,saving cost about 40.4 million yuan.
This paper introduces the application of infrared thermometer on coke oven.The temperature of coke cake is rapidly displayed through the on-line automatic measuring, which guides the heating regulation of coke oven.Meanwhile,by using the thermometer,the work intensity is eased; the accuracy of measurement is increased,and the heating regulation is improved.
This paper describes the classification,composition and nature of coal andintroduces basic conditions of high temperature coal tar hydrogenation.The principle,technology,difficulties and production status of the hydrogenation is outlined as references for the project estimation.
This paper introduced the principle and process flow of desulfurization by mono ethanolamine method and indicated some corrosion occurred in the process equipment.For the position apt to be corroded，measures can be taken by using anti\|corrosion materials or by adding corrosion inhibitor to MEA solution.The equipment should also be prevented from blockage to reduce desulfurization efficiency.
This paper analyzed the reason for high content of naphthalene in COG after gas primary cooler and raised a solution by technical innovation,which shows economical,feasible and effective.
On basis of newly-developed process of coal tar separation at low temperature and coal tar separation device,and in order to improve the extraction rate of coal tar,an analysis is made in this paper from aspects of quality of solvent,properties of the coal tar and operation temperature.Optimized measures are taken to improve the extraction rate of coal tar.
This paper analyses the HPF desulfurization process and describes reasons of the low yield of ammonium sulphate. After taking advanced measures，the condition is proved and ammonium sulphate yield can reach about 0.85%.
This paper described the harmfulness and solution to the carbon deposition and coking problem in the further COG desulfurization system in methanol production.To this end，measures have been taken by equipment modification and process innovation so as to minimize the impurities into the further COG desulfurization system for a sound performance of the hydrogenation catalyst and longer life expectancy of the equipment.
In order to deal with difficulty in treatment of HPF desulphurization waste liquor,ammonium salt is extracted from the waste liquor.In this way,the waste liquor is recycled and high economic value ammonium salt products are made so as to recycle the sources.
This paper studied the relationship between the aromatic lipid ratio of mixed solvent and the density at a certain temperature in order to improve the production efficiency,reduce the production cost and judge the aromatic lipid ratio of mixed solvent rapidly. Experimental results show that there is an obvious linear relationship between the aromatic lipid ratio of mixed solvent and the density at a certain temperature,also the linear relationship has guiding significance to the production.
The coke oven exhausting system consists of gas collecting main,gas exhauster,primary cooler and exhauster speed adjusting gear.It is used to adjust the speed of gas exhauster to keep a stable suction force before primary cooler and stable pressure in gas collecting main,so coke oven gas can be transmitted stably.Two models of working condition are established to control the system with different GPC parameters.The result shows that this system has strong robustness to restrain disturbance,and stable transmission of raw coke oven gas is achieved by the gas exhausting system.
A new technology of refined anthracene preparation by emulsion crystallization method is studied in laboratory where the factors affecting the quality of refined anthracene，such as amount of emulsifier，ratio of water to solvent (w/w) and amounts of additives，etc. have been investigated.The result shows that the purity of pure anthracene can reach above 95% and meet national specification Gr.I after primary emulsification when a compound emulsifier (SDBS+Span20) is adopted and acetophenone is used as solvent.
Based on the analysis for the composition of coking crude benzol and coke oven light oil，the feasibility of hydro-refining by coking crude benzol mixed with coke oven light oil is put forwarded according to an appropriate proportion of feedstock.The operating parameters can be adjusted accordingly as per design requirement and industrial standard so that the final product can meet national specification and solution can be found due to the insufficient feedstock in the market at present.
This paper introduces the categories of combustion additives，summarizes the influence of oxidant and catalyst to coal combustion property and the influence of desulfurizer and denitration agent to the discharge of pollutants after combustion.The use of coal combustion additive can effectively improve coal combustion property，reduce the emission of SOx and NOx，playing an active role to energy saving and pollutant discharge.
This paper introduces the study and calculation process of the performance-cost ratio of the coking coal used in HanSteel. The performance-cost ratio of coal mines is also compared to select the superior mine. The result shows that with such comparison,coal blending cost can be reduced to certain extend on the premise that the coke quality is stable.
This paper describes a series of new innovations as energy-saving & environmental protection cases in coking plant of Ningbo Iron & Steel Co.,Ltd.,such as VVVF technology,energy-saving type coke oven lid,thermal insulation layer in oven door,CDQ process,utilization of COG condensate at final cooler,large indoor-type circular coal/coke yard,coal water distillation by tubular furnace,salt extraction from desulfurizing liquid and high-performance microbe for waste water treatment,etc.,which have been successfully used in the plant.
Comprehensive evaluation of individual coal is carried out taking coal ingredient index as main technical method，and combining regular indexes and coking indexes of 40kg pilot battery.Several kinds of new coal resources and the coal resources in use are evaluated and compared.Two new coal resources are selected for 7.63m pilot battery.The selecting range of coal resources is widened.
This paper analyzes the influence of blending coal grain size to the production of coke oven battery after the coking chamber is increased.The influence of quantity and quality of crushed coal to the production of battery shall be considered for the determination of its grain size.The grain size shall be controlled to ～70% under normal condition.When the moisture content of coal in monsoon is higher than 13%,grain size can be suitably increased to 70%～75%.
Based on the actual situation of the coking plant of ShaoSteel,coal moisture control (CMC) technology is recommended.It can be seen through data comparison that CMC technology is good for energy saving and environment protection,and can create 82 040 000 RMB economic benefit every year.For a battery of 1.2～1.5 million t/y,the repayment period of investment is 4 to 5 years,so it is worthy for implementation.
Wet quenching water pump is raised by calculating to solve the maintenance difficulty due to original low position.Whether the water pump is installed above ground or not is related to local atmosphere (ATM) and installation elevation depends on ATM,necessary NPSH as well as suction resistance of pipe.
The process of 190t/h double chut CDQ in Anyang Steel,and the application of some key equipment such as heat-pipe exchanger,double chute,multi-tube cyclone separation de-dustor were described.Practical production shows that the application of such equipment can increase the utilization of CDQ heat power,reduce the possibility of coke floating,improve CDQ de-dusting effect,and provide favorable conditions for the stable running of the whole CDQ system.
This paper describes main processes and structural features of the swirl plate demister which had been put into numerical simulation in the internal flow field by fluid finite element software.The test shows flowing status,and distribution of pressure field and velocity field of the coke oven gas inside the swirl plate demister.The results are also analyzed in this paper.
This paper makes a conclusion for dry desulfurization and wet desulfurization,introduces the principle and methods of desulfurization waste water treatment such as partial conversion,complete conversion,multistep crystallization and diaphragm separation,and analyzes the problems of each method.
This paper described the principle and operating procedure for determination of NH4SCN content in desulfurization liquid by Fe-thiocyanic acid root complexing colorimetry and the test for interfering ion of SO42-,S2O32- and S2-.This method is proved to be simple in operation,sensitive in reaction and high in accuracy,which could rapidly determine the NH4SCN content in desulfurization liquid.
This paper analyzes the factors affecting the quality of ammonium sulfate in the production.In view of the problems such as the appearance,free acid and black particles in the ammonium sulfate,we have to upgrade the product quality,minimize off-spec.rate and maintain high quality rate by improving technical process and management.
This paper describes different treatments for waste HPF desulfurizing liquid and analyzes operating cost and investment estimate for different HPF desulfurizing liquids and sulfur as well.The analysis shows that it costs very few but with big pollutants by blending the desulfurizing liquid with coking coal and that it costs a little bit more but not a sustainable investment in the long-run by extracting salt from the desulfurizing liquid and thirdly it costs high but can be recycled into the coking process by acid-making which is achievable to a win-win situation in terms of economic benefit and environmental benefit.
This paper analyzes factors of affecting desulfurization efficiency in vacuum potassium carbonate desulfurization process,offering references for production practices.Improvements are made according to actual situation so that the desulfurization efficiency,as a result,can be remarkably increased.
In this paper,problems in benzol scrubbing system under negative pressure are analyzed.Based on behaviors of crystals,process parameters are adjusted to solve improper temperature control,low efficiency of wash oil regeneration as well as blockage due to long time crystal deposit.Normal production can be resumed as a result.
A new refining process of crude benzol by catalysis and chlorination is introduced in this paper, including pretreatment,catalysis and chlorination,stripping by alkalify,distillation and waste treatment as well.This process appears features of short flow,low consumption and high quality product.
This paper introduces the principle,method and result of acid making offgas control with coal water.This process is simple and has high desulfurization efficiency.SO2 and SO3 content in acid making offgas can be reduced to less than 30mg/m3,at the same time nitric oxides are absorbed.Economic benefit and environmental benefit are remarkable.
Based on the problems arising from the operation of original sulfur melting kettle,the operation of NF900 internal separation type sulfur melting kettle is introduced,which shows a preferable effect.
This paper described the general situation of benzol hydro-refining equipment and some clogging at heat exchanger in hydrogen adding unit and analyzed the causes.The analysis shows that the clogging can be solved by controlling the quality of light benzol feedstock,adding inhibitor,establishing a perfect management system for residue removal and disposing the residual oil from pre-evaporator and evaporator,etc..
High temperature compressive strength of coke in the presence of different gases such as N2，CO2 and 50%N2+50%CO2 is studied under laboratory conditions to analyze the influence of temperature and solution loss reaction to the high temperature compressive strength of coke.The result shows that with the increase of temperature，CO2 concentration and solution loss reaction extent，the high temperature compressive strength of coke decreases.The coke enduring a weak solution\|loss reaction tends to maintain the compressive strength of coke under high temperature.
This paper introduces the utilization status of low rank coal and the problems during thermal conversion,summarizes the influence of pretreatment technologies such as hydrothermal pretreatment,acid pretreatment,thermal pretreatment,solvent swelling,oxyalkylation and hydrogenation pretreatment to the structure,pyrolysis reactivity,tar quality and yield of low rank coal.It is proposed that with appropriate pretreatment technology,coal liquefaction conditions can be lowered,thermal conversion efficiency is increased,and tar quality is improved.Therefore,the goal of using low rank coal in a clean and efficient way can be achieved.
Influence of solution loss reaction temperature to the thermal properties of high reactivity coke
Slag,used as catalyst,is added to coking coal to prepare high reactivity coke.The influence of solution loss reaction temperature to the thermal properties of high reactivity coke and the change of coke structure after reaction are studied.The result shows that coke reactivity is improved with the addition of slag;coke reactivity increases linearly with the temperature rise of solution loss reaction,while the coke strength after reaction decreases slowly at first,then sharply;and the specific surface area of coke after reaction increases first and then decreases.
By calculating single\|pair vertical flue of 6m battery, the result is almost consistent with the design value.Accordingly,this paper has simulated six different heating modes in vertical flue as different work state and discussed the coefficient of excess air influence on nitrogen oxides generation.
Taking 5# and 6# coke oven as the research object,this paper refreshes PLC control system for existing coke ovens to realize factor K2 of automatic real\|time calculation.After using the automatic calculation method,K2 value can be calculated faster and more accurate so as to improve the production efficiency of coke oven and coke quality.
The changes of Y value,volume curve of gelatinous layer and X value of five individual coals under different bulk density are studied.The result shows that when the bulk density is increased from 0.75t/m3 to 1.2t/m3,Y value of gas coal,1/3 coking coal,fat coal and coking coal increases by 2.5mm,5.0mm,6.3mm and 5.8mm respectively,while there is no significant increase for lean coal; the volume curve of plastic layer for 1/3 coking coal changes from zigzag mountain type,which indicates that with the increase of bulk density,the plastic layer property of 1/3 coking coal is similar with that of fat coal,while the plastic layer property of gas coal,fat coal,coking coal and lean coal doesn’t change too much;X value of all the five individual coals decreases obviously with the increase of bulk density,and gas coal,1/3 coking coal fat coal and coking coal show obvious positive expansion during coking process.
Emission control measures of dedusting system during truck loading in coke plant
With the measures like balance dust bin negative pressure,guide air flow of rotating dust discharge valve,adjustment of connection between dust bin and humidify facility etc. during dust humidifying so that dust can be evenly charged and water is properly supplied.To this end,the dust emission has been basically eliminated and the work environment has been improved.
To correctly and completely configure relay protection device of the motor in CDQ circulating fan is a critical issue of electric engineering of circulating fan.The author has considered the technical application such as sampling value differential protection algorithm and magnetron balance differential protection etc.during motor non\|work frequency operation.And more solution has been made for relay protection of the motor in CDQ circulating fan.
Regarding to the traveling system of charging car and pushing car for stamp\|charge battery No.3 and No.4 in PanSteel,the limitation of existing anticollision method and device is analyzed.An anticollision solution using FK-ULS type laser anticollision alarm is proposed,which improves the traveling safety of charging car and pushing car.
In the light of practical coal charging,coke pushing and CDQ process in coking industry,the rationality and performability of the limitation on emission required by Emission Standard of Pollutants for Coking Chemical Industry (GB 16171—2012) are analyzed;countermeasures and suggestions are also given to cope with the difficulty in execution of the standard.
By the battery production practice,the battery heat consumption has been reduced by the measures such as lower coke cake central temperature,lower free space temperature,increase charging quantity of each chamber and stable coefficient of excess air etc.And better economic results have been achieved.
Using polyethylene glycol as modifying agent,the process of reducing the content of benzo[a] pyrene in coal tar pitch under solvent condition is studied.The study shows that when the reaction solvent ratio is 2∶1 in volume between cyclohexane and toluene,the sulfuric acid and polyethylene glycol 600 used are 6.67% and 10% in weight of the coal tar pitch respectively,and the reaction takes place under the temperature of 80℃ for 5h,benzo[a] pyrene can be removed up to 85.59%.
This paper introduces the improvement details and technical features for new process of ammonia distillation by tubular furnace.After improving,the system can run steadily and continuously with 120t/h of handling waste water and 95.7mg/L of ammonia nitrogen in the waste water,lowering 37.2%.
This paper introduces three crude benzol distillation processes and makes comparison in respect of process features,media consumption and operation cost.The result shows that negative crude benzol distillation process with steam consumes less steam,separates less water for production of crude benzol,and has good economic benefit for low cost of raw material,less investment and low running cost.
De-heavy tower is operated under negative pressure,so it is very important to keep continuous and stable running of vacuum unit.This paper analyzes the factors that affects normal operation of vacuum unit.Good results were obtained after technical modification of vacuum unit.
Through phydical and chemical dynamic simulation experiment,the influence of different coagulations to the degradation property of inorganic pollution factor of wastewater was evaluated.The study indicated that M-180A/B can remove 80% of T-CN and F-.Provided constant water inflow,if the reation time extends by 1 time,the removal rate of each coagulation to T-CN and F- increases to different extent.
Coke-plant wastewater,contaminated by various pollutants,consists of complex components,and it lacks biodegradability.The discharging water after the advanced treatments of hyper-filtration and nanofiltration membrane can be used for recycled water.The factors that will influence the running of the membrane treatment system such as the inlet water quality,operation mode and membrane cleaning are summarized.
After application of coal moisture control in coking plant of TaiSteel,problems were found during consequent treatment of tar\|ammonia separation and ammnia liquor,such as block of flushing liqour nozzle,high resistance in cross\|pipe primary cooler,and decreasing of tar quality.With the addition of demulsifier,the problem in tar\|ammonia separation was solved,so the production was stablized.
Compared with rich-oil heaters,using pipe still leads to accidents every now and then,and wash oil inclines to deteriorate.As steam becomes the heat source in rich-oil heaters,the safer process enhances the quality of recycled wash oil,lowers the consumption of it,and steps up the crude benzol production significantly.
By means of precipitation-crystallization,the secondary salt in desulfurized potassium carbonate waste solution can be utilized to retrieve CuSCN and K2SO4.The optimum technological conditions are obtained through experiments.In addition,the concentration of secondary salt in waste liquid becomes much lower.
This paper elaborates the technical principal and the process control of absorption unit and desorption unit for ammonia scrubbing with ammonium phosphate solution and analyses problems such as pipe blockage,exhaust emissions during the production to optimize the operation and process and improve the efficiency of ammonia removal.
According to the standard and combining with the actual situation，this paper proposed some actions should be taken on site after discontinuing gas facilities to have a better understanding of the standard.
Crucible coking experiment without coking coal is carried out by taking the mixture of Xuzhou gas coal and Zaozhuang fat coal as basic coal material,and adding coke fines,lean coal and anthracite coal of various sizes.The coke optical texture,coke micro strength index and structure strength index of obtained crucible coke are measured and tested.The result shows that with the addition of inert materials,OTI of coke increases,while I+Mf+FF decreases.Among the three inert materials,addition of coke fines is the most effective way to improve coke micro strength and structure strength.The smaller the inert material size,the better the coke quality.
This paper introduces the development of electric steelmaking in China and abroad,elaborates the development of graphite electrode and the research and development process of needle coke in China,and analyzes the international and domestic market situation and the overall trend of needle coke.It points out that research on the production process and technology of domestic needle coke shall be strengthened to improve the quality of needle coke,and investment to needle coke in oil system shall be increased.
This paper studies on technical properties of the blast furnace injection for flaming coal and its semi coke products.The result of the experience shows that grindability and burning rate of flaming coal are better than that of semi coke,while semi coke has higher calorific value,better safety performance,lower volatile,and more suitable for blast furnace injection than flaming coal.
Thermal extraction of fat coal at different temperatures and in different solvents and the properties of extracts are studied.The result shows that the extraction yield first increases with thermal extraction temperature rising,and reaches peak value at softening point,and then decreases with the rising temperature; and the extraction yield of fat coal increases obviously with solvent polarity.Thermal gravimetric and infrared analysis shows the variation of extracts structure.The feature of containing nearly no ash is expected to be the breakthrough for clean use of the coal.
A systematic analysis and conclusion have been made on the production data and phenomina such as temperature of oxidation layer in gasification furnace,fluctuation of oxidation layer,gas composition,tar yield,gas temperature and pressure at outlet of the furnace during industrial production offixed bed gasification of Huolin River lignite under atmospheric pressure,to show the particularity of fixed bed gasification of Huolin River lignite under atmospheric pressure.
This paper introduces the negative influence and energy saving effect of the third generation coal moisture control technology to coking and gas purification system,analyzes reasons and proposes solutions.
This paper analyzes the advantages and disadvantages of traditional coke cake center temperature measurement and modern automatic coke cake temperature measuring system.As to the difficulties in coke cake center temperature measurement of 7m coke oven battery,it is recommended to adopt horizontal tube inserting method to measure the coke cake center temperature,which has been applied to large scale coke oven battery successfully.
By comparison of old and new technologies in waste gas flue heat exchange,with description of waste heat recovery unit and by analysis of economic benefit for the new technology,the waste heat recovery unit from coke oven waste gas flue is highlighted in this paper,which is characterized with lower investment,short payback period,lower operational & maintenance cost and a remarkable economic benefit.
With the study on each individual coal quality，coking characteristic and coal fineness，and with reference the data obtained from 40kg pilot coke oven battery and quality requirement to coke of 1 750m3vanadium-titanium blast furnace，6.25m stamp-charging coke oven battery is undergone industrial demonstrating test.An optimum and economic coal blending structure for vanadium-titanium blast furnace is proposed，which can fully play the advantage of stamp-charging coke oven battery.
This paper introduced the causes of damage of water seal tank for CDQ and its improvement method.Although improved water seal tank accumulates a thicker fouling,the overall structure has not suffered from any substantial change,with service life over four years.
The reasons and main influencing factors for the black smoke discharged from the chimney of stamp-charging battery,and corresponding measures such as optimizing operation,narrow the coal bunker and adjusting coal blending structure and so on are taken.As a result,the pushing current is reduced to 105～120A from 150～170A,and no black smoke is discharged from the chimney any more.
Application of sealing socket joint of medium-temperature pitch in 6m coke oven battery
This paper introduced a new technology for socket joint of ascension pipe by sealing with medium\|temperature pitch,which has successfully been used for four 6m coke oven batteries in terms of improving operating environment and a remarkable economic benefit by 330,000 RMB yuan all year around.
The autotrophic nitrobacteria Z2 is isolated from the activated sludge in the coking waste water treatment system.The strain Z2 nitrification effect can reach up to 100% after four days in culture medium.The optimized nitration conditions of this strain are tested pH 8.0 with shaking speed of 250rpm at 30℃ under different circumstances of temperature,initial pH and shaking speed.The research on different inoculation amount shows that increase of inoculation would benefit nitrification because the nitrification of the tested strain can not be inhibited when the concentration of nitrite nitrogen is increased from 101.51mg/L to 507.55mg/L.Furthermore,the increasing culture medium pH during the nitrification could be beneficial to the nitrification in theory.
This paper studies the influencing factors such as microwave processing time，microwave power，FeSO4 dosing amount，H2O2 dosing amount，H2O2 dosing times and pH value during coking wastewater treatment by Microwave-Fenton oxidation.The optimum process conditions are determined by the experiment：pH value of wastewater：3，FeSO4 dosing amount：300mg/L，H2O2 total dosing amount of H2O2：900mg/L，H2O2 dosing times：3，microwave power：500W，temperature：50℃，reaction time：30min.the removal rate of turbidity，chroma and COD are 97.59%，95.62% and 86.21% respectively.The wastewater after treatment is clear，and the remaining COD is 50.34mg/L.The turbidity，chroma and COD meet the requirement of industrial recirculating water standard.
This paper described a method to control the secondary salt concentration from echanism the secondary salt in desulphurization and analyzed the factors affecting the concentration of the secondary salt in real desulphurization production by HPF,such as solution pH value,volatile ammonia content and catalyst concentration,etc..
As the QI content in coal tar and pitch of Meishan branch appears lower than normal，this paper introduced a solution that a blended oil and/or the coal tar with high QI content bought from outside the company are used to increase the QI content in the pitch. This blended oil can be used to produce medium\|temperature pitch and modified pitch so that the ratio of first-grade products can be increased due to the improved QI content.
This paper introduced a new technology of waste heat recovery from gas primary cooler，by which chilled water can be prepared by recovering the waste heat from the upper stage circulating water of the primary cooler in summer and heating water can be heated up by recovering the waste heat from the medium stage circulating water of the primary cooler in winter so that the waste heat from the gas primary cooler can be fully utilized，energy consumption can be saved and environment can be improved.
This paper introduced an “anaerobic-anoxic-oxid-coagulation-sedimentation-fenton reagent process” in waste water treatment by Jinan Iron & Steel Group and also analyzed some common problems during waste water treatment，such as sludge aging and sludge poisoning，etc..Countermeasures were also given in this paper.
Refrigeration process is applied to the chilled water at the lower stage of COG cooler,and open cycle is switched to closed cycle,so that water temperature is reduced by 10~15℃,meeting the process requirement.After comissioning and start-up,cooling water flow reaches 200m3/h,CO2 emission is reduced by 12 000t/a,steam recovered by 69 120t/a,and water saved by 1 400 000m3/a.The energy saving and emission reduction effect is remarkable.
This paper analyzed the problems of Fenton catalytic oxidation method and presented suggestions in the application for biochemical waste water treatment, such as chemicals selection,dosing method,dosing preconditions,sludge scrapper running time,pH value regulation and additional baffle in coagulation sedimentation tank,etc.,which will better the quality of effluent water up to grade I of Chinese national standard.
H2S/SO2 analyzer used in sulfur recovery unit can effectively improve sulfur recovery rate,reduce the discharge of sulfide,help to save energy and protect environment. This paper introduces the working principle of H2S/SO2 analyzer,and problems found during application and solutions.
This paper analyzed the operating status of centrifugal fan under non-normal conditions and put forwarded solutions to overloaded running of the fan in winter, including precautions for the fan piping design and operation.
Different proportions of steel slag were added to coking coal to produce coke.Thermal property of coke produced was studied.The result showed that coke reactivity increased with the addition amount of steel slag until it reached a saturation point,while the coke strength after reaction decreased continuously.Specific surface area and SEM study showed that higher reactivity resulted in bigger pore size,which may link up each other,and consequently the specific surface area and coke strength after reaction were reduced.It was also observed that steel slag particles were uniformly distributed in coke.
This paper introduces the present situation of coking benzene refining process in China,analyzes the features of different processes with respect of solvent,compares the effect of NFM and SUL-COS in extractive distillation process,and provides suggestion on process selection.Extractive distillation process is more suitable for coking benzene refining for its advantages of low investment,less equipment unit,lower pollution risk,high recovery rate and production purity,less energy consumption and operation cost,and good adaptability of raw material.
One of the main reasons why the pollution discharged from stack of coke oven battery exceeds the limits regulated by environmental protection standard is the leakage of raw gas from oven chamber to heating wall with going through micro cracks of the chamber wall.Therefore to keep tightness of the oven walls during long period of operation is the important condition for the oven battery to reach the environmental protection level required by the standard.The RPR-SL technology is a kind of “precise maintenance and repairing” technology of the oven chamber which can effectively diminish the micro cracks of the walls causing the leakage of the raw gas.It is also regarded as the technology eliminating pollution sources to reduce the pollution discharged from the stack of the coke oven battery.
In this paper,the coke thermal property is expounded,and the impacts of alkali metal,alkali-earth metal,zinc,lead and chloride on the coke thermal property are analyzed.Furthermore,some measurements are proposed like improving the coke thermal property and standardizing the operation of blast furnace,which will be instructive for the blast furnace to operate stably and trouble-freely.
Influence of petroleum coke on caking property of blended coal and coke property was studied through research on the features of petroleum coke and coal blending and coking experiment.The result showed that addition of petroleum coke will reduce the caking property of coal.Using of petroleum coke added coal for coking will reduce coke ash content,increase sulfur content in coke,reduce the cold strength and increase the hot strength of coke.
Take the actual production data of the 6m coke oven and the 2 800m3 blast furnace as objects,the paper studies the impact of sulfur content in the coke on the quality index of coke,the operation index of blast furnace and the quality index of molten iron,meanwhile,it discusses the comprehensive influence of the change of sulfur content in the coke on the cost of the coke and the cost of the molten iron.
This paper describes the calculation method of pressure drop and temperature drop of main steam of CDQ boiler system.Based on the different distances between CDQ boiler and turbo generators, the pressure and temperature of main steam at the outlet of CDQ boiler is calculated.It is found through comparison that pressure drop and temperature drop can be reduced by shortening the distance between CDQ boiler and turbo generators,so as to increase economic benefit.
Based on coke oven heat balance calculation,the relationship between excessive air coefficient and coking heat consumption is analyzed.Heat taken away by waste gas increases if the excessive air coefficient is too high,resulting in higher coking heat consumption.Combining with the data measured at site,a rational oxygen range contained in flue gas is worked out to realize complete combustion of gas,and fulfill the purpose of energy saving,environment protection,economic beneficial,low coking heat consumption and higher production capacity of coke oven.
Through introducing the present storage form of feed coal in the coking plants,this paper mainly considers several aspects such as the ratio of coal tonnage investment,the investment recovery time,the generated economic benefits by adding some weatherproof measurements,as well as the covering area,thus instructing the coking enterprises,in accordance with their own conditions,to choose the right suitable storage facilities of feed coal.
Coal injection experiments with different oxygen enrichment and different proportions of de-dusting ash show that the combustion rate of blast furnace PCI coal doesn’t change so much with addition of de-dusting ash up to 5%.In actual application，addition of 1.3% de-dusting ash brings about less influence on blast furnace indexes，but remarkable economic and environmental benefits.
This paper introduces the corrosion mechanism under the insulator of coking equipment and analyzes its effect factors as well as the protective measurements，in which the metal-protective coating is the most basic measurement，and additionally proposes the application of thermal insulating coatings to the coking equipments.
This paper analyzes the reason why the 5.5m stamp-charging coke oven has bad effects of charging emission control,and then the corresponding improved measurements are adopted.In addition,some notes during the system operation are put forward.After the improvements,the effect of emission control during coal\|charging is improved,and the phenomenon of yellow smoke emitting from the pusher side during charging is completely eradicated,and the maintenance of ascension pipes and smoke abatement devices is reduced as well.
In order to meet the requirement for recycling of treated coking wastewater,methods of flocculation and microwave-Fenton are combined to treat coking wastewater.The influence of dosing H2O2 and Fenton agent for several times and influence of combination dosing of flocculation and microwave-Fenton on coking wastewater treatment are studied.Based on the comparison between several processes,it shows that the effect of flocculation-microwave-Fenton method is obviously better than flocculation and microwave-Fenton.The optimum combination order is flocculation before microwave-Fenton.
This paper makes a comparison between positive and negative HPF desulfurization processes with respect to process features and economic benefit as well as process equipment,product,raw material and consumption indexes.The result shows that these two processes are similar in operation cost,but positive HPF desulfurization is more economic with regard to construction cost,therefore,positive desulfurization process is broadly adopted in coking industry.
This paper describes the wet desulfurization technology taking ammonia，which is contained in the gas，as alkali source and OMC-hydroquinone as catalyst.Production practice shows that this technology is very effective in desulfurization，and produces no wastewater.It is a clean production technology.
This paper introduces the design parameters of ammonia liquor circulating system of 7.63m coke oven,design of emergency system,ammonia liquor process flow,main equipment and problems found during production,discusses the compilation and implementation of maintenance scheme of ammonia liquor circulating system,production adjustment of coke oven,balance of cooling water,and prevention and control of production and environmental protection risks.
Pitch samples are molded by cold inlaid resin，and then grinded and polished by automatic grinding and polishing machine with different size grade waterproof sandpaper.The samples are observed and measured by reflection type polarizing microscope.Mesophase content is obtained through area percentage method.This method can not only avoid the influence of mesophase size，but also measure the proportion of different sizes of mesophase.
This paper introduces some engineering examples of advanced treatment of coking wastewater after biochemical treatment.Considering the features of biochemical tail water,a new treatment process combining pipe chute sedimentation,primary filtration and resin absorption is proposed.The removal rate of chromaticity,total cyanide content and suspended solid of tail water after treatment are 89.7%,88.1% and 69.6% respectively.The indexes of discharged water are better than that specified in Emission Standard of Pollutants for Coking Chemical Industry GB 16171—1012.This method has good application prospect.
This paper introduces the working principle of horizontal spiral centrifuge.Its application in the sludge dehydration treatment of coking wastewater shows that the centrifuge has the advantages of high capacity，high automation level，simple maintenance，clean and pollution free and low cost，so it is worthy of popularization.
With regard to the problem in conventional tube furnace that waste heat in tail gas is not recovered for reuse，a new technology is developed to recover and reuse the waste heat of tube furnace tail gas.Under the precondition that the quality of ammonium sulfate meets technical requirement，through process modification of tube furnace and equipment of ammonium sulfate production system，the waste heat of tube furnace tail gas is comprehensively used，process energy consumption is reduced，and environmental condition is improved.
This paper briefly describes the application of closed-circuit circulating cooling system in gas purification system，analyzes the system process arrangement，process features and existing problems，and puts forward improvement measures to keep stable production. Closed\|circuit circulating cooling system helps to reduce new water consumption per ton coke in coking industry，which brings about huge economic benefit.
ISSN 1001-3709 CN 21-1164/TQ Sponsor:ACRE Coking & Refractory Engineering Consulting Corporation,MCC Postal Code:8-28
