Sulphuric Acid Production Research Articles

Optimal points of operational parameters of sulphuric acid, phosphic acid, and ammonia production process

PT Petrokimia Gresik is the most complete fertilizer producer in Indonesia and produces various types of fertilizers. NPK is a fertilizer that contains nitrogen (N) to make plants greener, phosphorus (P) to stimulate root growth, and potassium (K) to make plants more upright and sturdy. This study aims to determine the optimum value of using sulfuric acid, phosphoric acid, and ammonia so as to obtain the best value in producing NPK fertilizer. This research method uses quantitative descriptive research methods by collecting secondary data, namely the use of sulfuric acid, phosphoric acid, and ammonia for a period of 1 year. Researchers use multiple regression analysis to determine whether or not there is an influence between the three variables to be studied, then the data is processed and analyzed to determine whether the regression model used is feasible to use before finally calculating the optimal point of NPK fertilizer production. The stages of data optimization in this study are the data collection stage, the data processing stage (descriptive data, parameter estimation, regression model), the data analysis and interpretation stage (F test, t test, IIDN assumption test for determining the optimum point), and the conclusion and suggestion stage. This study concluded that obtaining the optimum point for the amount of NPK fertilizer production can be done by regulating the use of phosphoric acid at 211.91 tons, Sulphuric acid at 844,099 tons, and ammonia at 308,055 tons. Total fertilizer production achieved with the use of optimum parameters amounted to 2085.38 tons.

Vertex-edge based resolvability parameters of vanadium carbide network with an application

A big amount of vanadium is used in the industry. It is used as a vanadium carbide stabiliser in steel production. Only 0.5 % vanadium in an iron alloy will double the tensile strength. Vanadium salts are used in leather, ink, dye manufacturing and yellow ceramic glaze. On the other hand, vanadium pentoxide is used as a catalyst, in the chemical industry, for the production of sulphuric acid and in the petroleum refinery industry. Resolvability parameter is the most discussed topic in graph theory. This helps to reorganise a network in a unique way, sometimes in terms of atoms (metric dimension) and sometimes bound (edge metric dimension). We studied resolvability parameters of vanadium carbide network in this article i.e. metric, edge metric and partition dimension. Among these metrics resolvability defined by parameters taking a subset from the set of vertices, if it has a unique representation with all the vertices, then it is called a resolving set. The number of elements in the smallest resolving set is called the metric dimension. While the number of elements of the minimal subset of vertices taking from vertex set is called the edge metric dimension, if the representations are unique of all edges and the set is called the edge resolving set. This study can have an effect in many ways in the research, particularly, with the help of some key points such as network structure analysis, material science via material properties, graph theory applications, predictive modelling, material testing and characterisation, as well as in industrial applications.

Optimized Production of High Purity Sulphuric Acid via Contact Process

Sulphuric acid (H2SO4) is of immense importance to the chemical industry and humanity. The use of Aspen Plus modeling, simulation, and optimization via the contact process has enabled the production of grade sulphuric acid. Notably, the research findings highlight the sensitivity of water flow rate to the maximization of H2SO4 production. Through these methods, a production capacity of around 8 tons per day was achieved, with a purity level of 98.9%. This achievement significantly contributes to meeting the demand for sulphuric acid in various industries. Moreover, exploring alternative sourcing methods, such as utilizing elemental sulphur, offers the potential for further optimizing H2SO4 production. The benefits of improving H2SO4 production extend beyond the chemical industry. Sulphuric acid finds applications in agriculture, petroleum refining, pharmaceuticals, and metal processing. Enhancing the production process ensures a reliable supply for these sectors. In summary, sulphuric acid is indispensable to the chemical industry and humanity at large. Aspen Plus modeling and optimization techniques have successfully improved the production of high-grade sulphuric acid, resulting in increased capacity and purity. Exploring alternative sourcing methods further enhances production possibilities. These advancements have wide-ranging implications, benefiting multiple industries and driving progress in sectors reliant on sulphuric acid.

Utilization of silica-enriched filter cake industry by-products as partial ordinary portland cement replacement

In recent years, industrial byproducts have been converted into useful and valuable commercial items. Reusing these byproducts plays a crucial role to ensure the circular economy and thereby safeguard the environmental impacts. In Ethiopia, the Aluminate Sulphate chemical factory disposes of filter-cake waste materials in landfills that have high silica content. The factory is using pure kaolin and other raw materials for the production of Aluminum Sulphate and Sulphuric Acid by burning at high temperatures. By-products materials were collected from the factory and then calcined (post-treated) at 600 °C for 2h in a muffle furnace. From Atomic Absorption Spectrometry measurement result, it is confirmed that the post-treated (at 600 °C/2h) silica-enriched filter-cake waste materials have a similar composition to Metakaolin (MK). Post-treated filter cake (named MK) became more amorphous having high reactive silica with very low impurities as it was calcined and quenched rapidly. In this study, the properties of blended Ordinary Portland Cement (OPC)-mortar samples were investigated with the addition of heat-treated filter cake waste materials (0%–20%) as a partial OPC replacement. X-ray diffraction, Fourier Transform-Infrared Spectroscopy, Differential Thermal Analysis, Scanning Electron Microscope, and Atomic Absorption Spectrometry were used to investigate the properties of mortar samples that contain post-treated filter-cake (MK) materials and OPC-cement. The flexural and compressive strengths of 10% MK + 90% OPC-mortar samples were enhanced at early curing ages, 7 & 28 days. Moreover, the flexural and compressive strengths of OPC mortars with 15% MK have been improved at 28 days of curing age. However, 20% MK + 80% OPC blended mortars have not shown any improvement in mechanical properties. Setting time, soundness, water absorption, and apparent porosity of cement pastes with the addition of post-treated filter cake (MK) are also analyzed.

The Application of conserved emissions of sulphurous gases for improvement of alkaline soils

The aim of the study is to provide integrated solution of environmental problems by help of conservation emissions of sulphurous gases in form of sulphur or treated cement dust and their application for improvement of Alkaline Soils. New ameliorants for improvements of Alkaline soils under laboratory conditions were obtained: electro-treated mixture of sulphurous and sulphuric acids, treated cement dust containing sulphite and sulphate salts of Ca. Two electrochemical methods for production of sulphuric acid and mixture of sulphuric and hydrochloric acids from sulphurous acid were developed and the electric energy requirement for their production is calculated. The process of retention of sulphurous gases, by water solution of cement dust is studied. It is shown, that for conservation of 1 t of sulphurous gases 2 t of cement dust is required. The influence of newly-received ameliorants on physical and chemical properties of Alkaline soils during their chemical reclamation and leaching processes was studied. The most ameliorative effect, obtained in the variant, where electrochemical treated solution of the mixture of sulphurous and sulphuric acids were used.

The influence of black shale weathering on riverine barium isotopes

Barium and its isotopes are receiving growing interest in their capacity to record the variation of the oceanic biological pump through geological timescales. Nonetheless, only little is known about the continental sources and processes that can drive the Ba flux and isotope composition to the ocean. Whereas the role of processes such as secondary phase formation, sorption and biological uptake on Ba isotopes has been recently investigated, the potential of various rock sources in producing a range of Ba isotope compositions remains poorly known. In particular, black shales often exhibit enrichment in Ba that might potentially be associated with various Ba isotope signatures.In this study, we report the isotope composition of Ba in rivers with different relative contribution of black shale rocks in their catchments, located in the Mackenzie Basin (Northwest Canada). Both the dissolved and solid loads of the Mackenzie tributaries are enriched in heavy Ba isotopes with respect to the continental crust, which is consistent with an additional source to the weathering of igneous and siliciclastic rocks. Although the dissolved Ba abundance is partially driven by weathering processes, the river dissolved Ba isotope composition rather reflects a binary mixing between 1) a “classical” siliciclastic source (with a Ba isotope composition close to that of the upper continental crust δ138Ba ∼ 0.15 ± 0.05‰) and 2) an isotopically heavier source especially present in the Mackenzie Mountains (with a δ138Ba ∼ 0.40‰). The positive relationships between dissolved δ138Ba and radiogenic osmium isotope ratios, as well as with sulphuric acid production, indicate that the heavy Ba source is tightly linked to the weathering of black shale. Although the exact reason for such heavy Ba isotope signatures remains elusive, this study emphasises the potential of black shale weathering in shifting the Ba isotope composition of the dissolved flux to the ocean towards heavier values.

Prospects of Using the Functionality of Zirconia-Silica Hybrid Materials Towards Hazardous Metal Ions Recovery from Model and Real Wastewaters Raising from Industrial Production of Sulphuric(Vi) Acid: Batch Adsorption Experiments and Mechanism Study

Prospects of Using the Functionality of Zirconia-Silica Hybrid Materials Towards Hazardous Metal Ions Recovery from Model and Real Wastewaters Raising from Industrial Production of Sulphuric(Vi) Acid: Batch Adsorption Experiments and Mechanism Study

A simple model for desulphurisation of flue gas using reactive filters

Desulphurisation of flue gas is essential before it can be released safely into the atmosphere. One way of removing sulphur dioxide is to use a purification device incorporating a reactive filter, in which the flue gas stream passes in front of a porous-catalyst-filled structure which converts the gaseous sulphur dioxide into liquid sulphuric acid. In this paper, we build and solve a simple mathematical model to describe the operation of a paradigm reactive filter. Our model captures the transport of sulphur dioxide through the device via advection in the main “outer” flow and diffusion through the catalyst structure along with the production of sulphuric acid. This sulphuric acid gradually accumulates in the filter rendering it less efficient. We determine the clogging time for an individual channel (that is, the time at which the entrance to the channel becomes completely filled with liquid) and explore how the concentrations of sulphur dioxide and oxygen and the thickness of the sulphuric acid layer change as the key dimensionless parameters are varied, comparing numerical and asymptotic results where appropriate. We then turn our attention to the device scale and solve our model numerically to determine the overall lifetime of the device. We vary the key dimensionless parameters and explore how they affect the efficiency of the device. In the physically relevant parameter regime, we find an explicit solution to the outer flow problem which agrees well with numerical solutions and provides a formula for the lifetime of the device. Finally, we propose a formula for determining the catalyst reaction rate, given data on the concentration of sulphur dioxide exiting the device.

The influence of the mixture of vermicompost and sulphur-perlite-containing waste on the yield and the quality of crops

Any type of material that increases soil yield, both qualitatively and quantitatively, to strengthen the soil and increase its fertility is called fertilizer. The current study examines the production of a new effective fertilizer. Results presented involve effects of new bioorganic-mineral compositions obtained from the combination of vermicompost and sulphur-containing waste from sulphuric acid production on the yield and quality of tubers (beets, carrots). An increase in the yield of tubers has been found to be 1.13–1.25 times when the bioorganic-mineral composition (~20 Mg∙ha–1) is introduced into the sierozem (serozem) soil. The best results are obtained with mass ratios in the range 30–45 and 55–70 for vermicompost and sulphur-perlite-containing waste, respectively. The effectiveness of the mixture of vermicompost and sulphur-containing waste is explained by the increased synergistic interaction of these components. The proposed composition has high structure-form-ing, water-retaining, nutritional and biologically active properties.

Double corrosion protection of sewage tunnel linings

ABSTRACT In sewer environments, there are complex chemical and microbiological processes with a reaction between the hydrogen sulphide, a gas produced by the used water, and aerobic feeding microorganism. This resulted in production of sulphuric acid which would cause long-term corrosion on cement based concrete structures. This corrosion process is known as “Microbiologically Influenced Corrosion“. Generally, the ordinary Portland cement-based concrete is not considered as a suitable material for direct exposure to acidic sewer environments. As such, it is necessary to prevent the aggressive environments from developing, as well as to prevent the corrosive environments from coming in contact with the concrete elements. A robust corrosion protection system must be specified and provided for the tunnels and underground structures to ensure the durability of these structures under the aggressive sewer environments and able to withstand a design life span of 100 years. Case example with discussion on seven proven corrosion protection lining systems based on current technology. Past experience of the tunnels is provided with further exploratory study in terms of cost effectiveness and quantity analysis for these seven lining systems to be investigated. A technical specification for Portland cement–based Microbiologically Influenced Corrosion resistant concrete is provided.

Modelling and Multi-Objective Optimization of the Sulphur Dioxide Oxidation Process

Sulphuric acid (H2SO4) is one of the most produced chemicals in the world. The critical step of the sulphuric acid production is the oxidation of sulphur dioxide (SO2) to sulphur trioxide (SO3) which takes place in a multi catalytic bed reactor. In this study, a representative kinetic rate equation was rigorously selected to develop a mathematical model to perform the multi-objective optimization (MOO) of the reactor. The objectives of the MOO were the SO2 conversion, SO3 productivity, and catalyst weight, whereas the decisions variables were the inlet temperature and the length of each catalytic bed. MOO studies were performed for various design scenarios involving a variable number of catalytic beds and different reactor configurations. The MOO process was mainly comprised of two steps: (1) the determination of Pareto domain via the determination a large number of non-dominated solutions, and (2) the ranking of the Pareto-optimal solutions based on preferences of a decision maker. Results show that a reactor comprised of four catalytic beds with an intermediate absorption column provides higher SO2 conversion, marginally superior to four catalytic beds without an intermediate SO3 absorption column. Both scenarios are close to the ideal optimum, where the reactor temperature would be adjusted to always be at the maximum reaction rate. Results clearly highlight the compromise existing between conversion, productivity and catalyst weight.

Oxidation of Sulphur Dioxide using Micro‐ and Nanoparticles of various Iron Oxides

AbstractSulphuric acid is the chemical with highest production rates in the world. At present, it is mainly synthesized using vanadium pentoxide as catalyst, which determines the applied production process particularly in terms of gas pre‐treatment and heat management. For processes, which cannot be run with vanadium pentoxide, alternative catalysts are required to make different SO2 qualities accessible to sulphuric acid production. Ferric oxides are a very promising alternative, since they combine higher thermal with improved chemical stability. Within this study, various ferric oxides were examined with regard to conversion rates and structural changes during application. Effects of crystal structure, particle size as well as thermal treatment and the influence of precipitation conditions were studied. Although conversion rates are very promising, it has become apparent, though, that these materials cannot compete with vanadium pentoxide in terms of conversion rate as well as long‐time stability, yet. Nevertheless, from the results of this study, it is clear that high potential lies in focused catalyst optimisation.

A detailed reaction mechanism for elemental sulphur combustion in the furnace of sulphuric acid plants

AbstractElemental sulphur combustion is traditionally used to generate SO2 to produce sulphuric acid that is consumed in chemical industries, but is now also being considered as an energy vector for power generation. Despite the fact that sulphur combustion has been practiced for decades, there are limited reaction mechanisms for its combustion chemistry, which is critical for the optimization of the sulphuric acid production process to maximize efficiency and reduce cost. In this paper, a detailed reaction mechanism is developed and validated with different sets of experimental data from lab‐scale and industrial plant studies. The reaction mechanism is used to conduct sulphur furnace simulations, where the effects of feed air/sulphur ratio and oxygen enrichment of air stream on furnace temperature and the concentrations of SO2, SO3, and O2 are investigated. The dominant reaction pathways in sulphur combustion, particularly for the production of SO2 and SO3, are identified. It was found that the feed air/sulphur ratio monitors the furnace temperature and can be used to obtain the desired O2/SO2 ratio at the furnace exit for the optimal operation of catalytic converter (for SO2 oxidation to SO3) that follows the furnace in the sulphuric acid plant. Moreover, high oxygen enrichment above 35% (while maintaining the desired O2/SO2 ratio at the furnace exit) significantly increased the furnace capacity through reduced total gas flow (thus decreasing blower energy requirement and equipment size). The developed reaction mechanism provides a method to obtain optimized furnace parameters to achieve high efficiency and reduced costs in sulphuric acid plants.

Consequence assessment using threat zone analysis on sulphuric acid production plant

The consequence assessment is one of the crucial methods in the process safety engineering fields to determine and quantify the threat zone derived on the respective chemical plant and this method will guide the designer regarding the most suitable preventive measure to avoid the disaster of a chemical plant. This work highlights the consequence assessment on sulphuric acid production plant using threat zone analysis, one of the steps in Quantitative Risk Assessment. The plant has decided to produce 80,000 MT per year of sulphuric acid in Malaysia with the selected site location of Kerteh, Terengganu. The process layout and location of the equipment installed for the processing steps of sulphuric acid production have been simulated by the Aspen HYSYS simulation software. All possible hazardous chemical for every equipment has been identified and the consequence assessment method focusing on threat zone distance was developed through the six steps of methodology to estimate the worst-case scenario. Distance of threat zone was simulated using ALOHA, MARPLOT and Google Earth software. Results show that the absorber tower produces the worst-case scenario among all equipment in the plant, which red threat zone of toxicity reaches more than 10 km to the surrounding area.

Pilot scale anion selectrodialysis for water reclamation and nutrient recovery from UASB effluent after nitrification, ultrafiltration and UV C treatment

In the frame of the increasing need of nutrient recovery and recycling the objective was to fractionate and concentrate nutrients from nitrified, ultra-filtered and ultraviolet C treated UASB effluent with anion selectrodialysis (aSED). Under these conditions it was possible to keep the system in operation for 14 days or even for 3 weeks with intermittent cleaning in place every week. When membranes developed in the frame of sulphuric acid production (PC-Acid 100 OT) were used as anion exchange membranes (AE membranes) instead of standard AE membranes (PC-SA) a 4.5 times higher current efficiency for phosphate transport was noted. The diluate of the aSED is reusable as e.g. cooling water for condensers. The product stream which is enriched in phosphate (5–6 mmol.L −1 ) and the brine stream which accumulated potassium (150 mmol.L −1 ) and nitrate (90 mmol.L −1 ) are suitable for nutrient recovery. During the optimization process the current efficiency for phosphate transport increased tenfold, from 0.7% to 7%. The product stream was fed to a lamella separator (with a molar Ca/P ratio of ± 1.93) to recover 98% of the phosphate. The recovered precipitate was free of magnesium and contained the equivalent of 30 to 38 m% P 2 O 5 ; XRD analysis showed the presence of hydroxyapatite. The Ca/P ratio of this precipitate decreased proportionally with the degree of aeration to expel dissolved inorganic carbon from the feed to the aSED, indicating less coprecipitation of calcium carbonate within the recovered calcium phosphate. • Anion selectrodialysis combines water reclamation with N, K and P fractionation. • Ca 3 (PO 4 ) 2 precipitated from the selectrodialysis product in a lamella separator. • The calcium phosphate (max. 82 m% ≈ 38% P 2 O 5 ) is only contaminated with CaCO 3 . • Up to 80% of K and nitrate-N is recovered and is concentrated 3.2 times. • By optimization the specific current efficiency for phosphate increased tenfold.

The feasibility of utilizing existing process streams in kraft pulp mills as a source of chemicals for lignin extraction

Lignin is a sustainable raw material with a high potential for use in the production of renewable products. While the market for lignin is slowly growing, lignin recovery via acid precipitation during the kraft pulping process requires the addition of chemicals that will impact the chemical balance of the pulp mill. This negatively affects both the environmental and business operations. Utilizing existing process streams as a source of chemicals will allow the mill to close the chemical loop and reduce emissions, which will have positive environmental impacts. This study investigated the internal production of sulphuric acid (H2SO4) and carbon dioxide (CO2) for use in lignin separation (also called extraction) at a Swedish kraft pulp mill. The process simulation tool CHEMCAD was used to model and analyze the wet gas H2SO4 (WSA) process to produce H2SO4. The chemical absorption process using monoethanolamine (MEA) to capturing CO2 was also analyzed. The utilization of the sulphur-containing gases to produce H2SO4 can generate an amount that corresponds to a significant lignin extraction rate. The CO2 available in the flue gases from a mill well exceeds the amount required for lignin extraction.

A Computer Simulator Model for Generating Sulphuric Acid and Improve the Operational Results, Using Operational Data from a Chemical Plant

The integration of both sensors and simulation in some industrial processes has received a large increase in the recent years, thanks to results such as increase in production indices or improvement in economic indicators. This document describes the development and validation of a simulation-based computer process for generating sulphuric acid. For this process, the data generated by simulation between the fixed beds of a catalytic reactor versus the results obtained using real data from a sulphuric acid production plant in the Antofagasta Region, Chile, have been used. This sulphuric acid production plant is designed for producing 720,000 tons of sulphuric acid annually, with a production capacity of 26 MW, which is used for both its own consumption and the Big North Interconnected System (SING, for its acronym in Spanish) and a sulphur consumption of 240,000 tons/year. For the simulation process, converter input variables such as temperature and gas flow to later observe the oxidation behavior under different operational scenarios were considered. To do it, a working method has been proposed and the software Aspen HYSYS® was used for the simulation. The simulation result was validated using design operational data provided by the company. The real results show a 99.9% of adjustment concerning the values obtained using the simulation. Based on the findings, a new operational scenario was created, and the economic indicators of the simulator implementation were determined: NPV=CLP 161,695,000 and IRR=53% with a 6% monthly production increase.

Experimental Study of Pyrite Oxidation at 100 °C: Implications for Deep Geological Radwaste Repository in Claystone

The oxidation of pyrite is one of the near field processes of the chemical evolution of clay rock planned to host a deep geological radioactive waste repository during operation. Indeed, this process can lead to transitory acidic conditions in the medium (i.e., production of sulphuric acid, carbonic acid) which may influence the corrosion kinetics of the carbon steel components of some disposal cells. In order to improve the geochemical modelling of the long-term disposal, the oxidation of pyrite in contact with clays and carbonates at 100 °C must be evaluated. In this study, special attention was paid to the pyrite oxidation rate thanks to an original experimental set-up, involving several pyrite/mineral mixtures and a reactor coupled to a micro gas chromatograph (PO2 and PCO2 monitoring). Although thermodynamic modelling expects that hematite is the most stable phase in a pure pyrite heated system (low pH), experiments show the formation of native sulfur as an intermediate product of the reaction. In the presence of calcite, the pH is neutralized and drives the lower reactivity of pyrite in the absence of native sulfur. The addition of clay phases or other detrital silicates from the claystone had no impact on pyrite oxidation rate. The discrepancies between experiments and thermodynamic modelling are explained by kinetic effects. Two laws were deduced at 100 °C. The first concerns a pure pyrite system, with the following law: r P y = 10 − 4.8 · P O 2 0.5 · t − 0.5 . The second concerns a pyrite/carbonates system: r P y + C a = 10 − 5.1 · P O 2 0.5 · t − 0.5 where PO2 corresponds to the partial pressure of O2 (in bar) and t is time in seconds. Different mechanisms are proposed to explain the evolution with time of the O2 consumption during pyrite oxidation: (i) decrease of the specific or reactive surface area after oxidation of fine grains of pyrite, (ii) decrease of O2 pressure, (iii) growing up of secondary minerals (Fe-oxides or anhydrite in the presence of calcium in the system) on the surface of pyrite limiting the access of O2 to the fresh surface of pyrite, and (iv) change in the pH of the solution.

A slurry emission off a pulp appeared after metallurgic gases wash of Balkhash copper smelting plant by spinning

A sulphuric acid is obtained of the metallurgic gases after smelting of feed materials and matte converting preliminary cleaned dry or wet method. A pulp appears after wet gases cleaning containing sulphuric acid solution, slurry and amorphous selenium. The sulphuric acid production at the Balkhash copper smelting plant differs from the identic one at the Zheskazgan copper smelting plant by cleansing solutions spinning off and extracting slurry out of them by sedimentation. By this reason Balkhash copper smelting plant discharge pulp 7-14 times as much as Zheskazgan copper smelting plant of clarified liquor. Pulp is a valued man-made raw material to extract rhenium off the solution, selenium iodine off the slurry. At present, a sorption technology of rhenium extraction off the solution is developed and tested in the pilot scale. Selenium is a second component worth mentioning considering its production at the Balkhash copper smelting plant. This article analyzes prospect researches of various methods testing of clear solutions obtaining, faults and benefits of straining by spinning. The results are provided of the slurry amount effect and amorphous selenium in the pulp, the speed and time of rotation of the centrifuge rotor. A rotor spinning velocity is established to be the main factor has impact on pulp separation into the clear solution and residue of every slurry compound, including amorphous selenium by spinning. This method according to calculations allows to a substantial energy costs saving comparing the pulp heating-straining.

USE OF SIMULATION MODELS FOR OPTIMIZATION OF THE CONTACT APPARATUS WORK IN THE SULFURIC ACID PRODUCTION

In the modern world, in connection with the rapid development of computer technology and software widely used A far of processes in chemical industry is continuous and a production lasts twenty-four-hour. The stop of such processes results in considerable economic losses. Realization of active experiment on a production is complicated (through the necessity of stop of productive process and risk of damage of industrial equipment a researcher). Realization of passive experiment often does not give to the researcher of sufficient information about the looked after object (through the very small rejections of entrance signals of object and impossibility of influence a researcher on every entrance signal separately). An attractive alternative in this case is creation of simulation model.The aim of the article is a publication of results of the use of simulation models for optimization of work of pin vehicle in the production of sulphuric acid.Creation of simulation model settles many problems. There is possibility to set any values of entrance signals independent of each other. There is possibility to design emergency situations. In the modern world, transients in chemical industry last during many hours. By means of computer simulation models information about a transient it is possible to get almost instantly (depending on the amount of calculations and power of the computing engineering).Of long duration continuous process the process of pin oxidization can exemplify in the production of sulphuric acid. Oxidization of sulphureous anhydride SO2 in sulfuric SO3 takes place in pin vehicles at the presence of vanadium catalyst. Into a vehicle there are four layers of pin mass. Pin mass is placed on grates. One of basic indexes of quality of work of pin vehicles there is a degree of contact xp, which is calculated on a formula.As evidently from the results of design, the identical values of middle temperatures (levels) are situated along direct. This surface can be used for development of the system of automatic control. Will set the problem to support such temperature condition at which a middle temperature would be in the second area (green area). Thus a management would be near to optimal and there would not be a risk of stop of reaction in case of sudden hit in the area of stop of reaction (white area).On the real object the system of automatic control supports the stationary temperatures of gas on an entrance to every layer of pin mass (catalyst). As a rule gas temperatures on entrances to every layer lie within the limits of 420-450 °C. A maximal temperature on an exit from the layer of catalyst folds close 600 °C. Decline of gas temperature to 400 °C and below given to the stop of reaction (and it is impermissible in a continuous production). Transients in a pin vehicle last a few hours. The new start of process stipulates the considerable losses of time (id est is a loss). Increase of temperature to 650 °C and higher results in the overheat of catalyst to his spoilage. In this case it is necessary to stop a process and replace a catalyst (and these are very considerable material charges). Realization of active experiment is simply impermissible clearly, that. A simulation model enables how pleasingly to influence on a temperature condition into a pin vehicle. There is possibility to investigate temperature conditions near to the emergency (at a temperature on an entrance to one of layers of catalyst close or to the temperature on an exit from one of layers of catalyst close 650 °C).For creation of simulation model it is necessary foremost to formalize an object. For the mathematical design of behavior of object (dynamics and statics) it comfortably to use the system of differential equalizations. Differential equalizations can be got analytically from material balances. It is also possible to get differential equalizations after treatment of results of passive or active experiment. On results the conducted imitation design it is possible to do next conclusions:1. An object is almost not sensible to short-term indignations. Id est there is not a necessity to design the system of automatic control with a high fast-acting. Recommended to steel of time for control system by a concentration and gas temperature approximately equal to 10 minutes.2. Most dangerous for the process of pin oxidization is an increase of concentration of SO2. A nominal concentration is 7,4 %. At the increase of concentration gas must be diluted by air (for normalization of concentration). At development of the system of automatic control it follows to take into account next limitations: maximal static rejection of concentration ± 0,1 %; maximal dynamic (short-term) rejection of concentration ± 1 %.3. Desirable (near to optimal) are tasks of temperature and concentrations within the limits of the second area. Dependence between an optimal temperature and concentration entrance.