The chemical and petrochemical industry places high demands on filtration systems and filter press architectures used with regard to chemical resistance and the relevant filtration parameters in order to achieve the highest possible end-product quality. As a result, durable, safe and efficient technology solutions as well as optimised and efficiently designed process parameters are critical for chemical processing applications. MSE Filterpressen® offers comprehensive and sophisticated filter press technologies in the field of solid-liquid separation and customer-oriented solutions to improve production, efficiency and end-product quality. Our chamber filter presses and membrane filter presses are the optimum solution for the specific chemical properties at filtration temperatures of -10 °C to 95 °C due to their process-technical variability in close cooperation with renowned suppliers.
They offer high filtration quality, high filtration rates, maximum washing efficiency and a high degree of dewatering. Furthermore, our computer-controlled regulation of the feed offers significant economic advantages in the filtration of the finest particles and the associated homogeneous filter cake. Thanks to our experience in the field of chemical application, we have successively optimised relevant processes in recent years in order to offer the best possible customer benefit. As a major filter press manufacturer, we are committed to helping our customers maximise their success.
Important process steps of MSE filter presses are: Cleaning, filtration, dewatering, drying.
EXAMPLES OF APPLICATIONS IN THE CHEMICAL INDUSTRY
In copper electrolysis, anode sludge accumulates as an intermediate product, which settles on the bottom of the electrolysis cell during the dissolution of the copper anodes and contains noble and insoluble minor elements, including especially gold, silver, selenium and tellurium. From this anode sludge, the precious metals are processed in a multi-stage process, so that they can be transferred to fine metals or recyclable intermediates during recycling and sold. For a modern and environmentally friendly precious metal extraction, the sludge must be dried to a residual moisture content of less than three percent. The dewatering process takes place with the help of a membrane filter press. The precious metal-containing anode sludge resulting from the copper electrolysis is fed to the filter press and then filtered and dehydrated.
The membrane filter press used here is part of an overall concept for anode sludge treatment and of significant relevance with the goal of energetic optimisation, the recycling of resources and emission reduction. MSE membrane filter presses are characterised by their solid, robust and high-quality architecture coupled with a high filtration quality and excellent dewatering results. Efficient drying of the anode sludge by means of a heatable membrane filter press via integrated heating plates (TCD) through which process steam flows at 120 °C*, CO2 emission reduction and energy savings of up to 35% is possible due to the elimination of further processing and the multi-stage heating of the anode sludge.
An anodising unit treats aluminium surfaces daily, among other things, with the aim of creating corrosion protection by generating an oxide protective layer through anodic oxidation. For this purpose, profiles and sheets for the construction industry, the automotive industry, but also for façade cladding panels are primarily treated and upgraded. When anodising aluminium, large quantities of rinse water are produced. This is due, on the one hand, due to the viscosity of the alkaline pickling solutions to be removed in the rinsing bath, which adhere to the product surface and on the other hand, the diffusion process on the product surface requires thorough rinsing after the anodising process. The rinse water is collected in the waste water treatment plant and subjected to a treatment. Here, the acidic and alkaline rinse water is brought together and neutralised.
With the addition of flocculants, this neutral solution is fed to the chamber filter press. The clear, solids-free filtrate is subjected to a post-treatment in filtration units of a final pH end inspection and then fed into the public sewer system with the remaining and permitted residues. The filter cake solid (aluminium hydroxide) remaining after the pressure filtration in the filter press filter is collected in containers and taken to the landfill. With their design-typical features, these are characterised in the rinse water treatment by high filtration rates and quality as well as an efficient configuration of the process which is optimised for the process.
For the large-scale production of aluminium pigments, the metal to be processed (aluminium) is first melted and atomised out of the melt after reaching the melting temperature. This results in irregularly shaped, spherical particles. This starting material, referred to in the industry as aluminium grit, is subsequently mixed by wet grinding in ball mills with white spirit and lubricant (oleic acid for non-leafing pigments and stearic acid for leafing pigments) by the so-called Hall method and are deformed to flakes and crushed. After grinding and subsequent screening of the agglomerates formed in the grinding process, the excess white spirit is filtered out of the resulting mixture (slurry) by means of filter presses and the pigment is concentrated.
In the last step, the dewatered filter cake, which consists of 80% aluminium pigment and 20% white spirit, is adjusted to the respective commercial form with regard to the exact composition and requirement (aluminium pastes have a metal content of about 65% and 35% solvent). In order to meet the increasing requirements in terms of fineness, purity, effectiveness and consumption minimisation, MSE Filterpressen® offers tailor-made solutions aimed at maximum customer benefit.
The industrial production of the yellow barium chromate, which is of particular industrial importance in the glass and paint industry as a pigment, is done by the precipitation of barium ions with chromate ions in a slightly acidic solution. The precipitated barium chromate is fed to the water-soluble admixtures of a solid-liquid separation device for filtration and mechanically dewatered with the aim of a puncture-proof filter cake. In barium chromate treatment, filter presses are primarily used due to the high degree of filtration requirements and outstanding dewatering results. MSE membrane filter presses are characterised by their solid, robust and high-quality architecture coupled with a high filtration quality and excellent dewatering results. The high dry matter content achievable with membrane filter presses makes it possible to reduce the downstream drying time and also the energy consumption.
The preparation of high-purity barium sulphate* (so-called Blanc fixe), which is used in particular as a filler, is first carried out by the reduction of crude baryte (barite) with carbon and leaching to a barium sulphide solution, which is then precipitated by the addition of sodium sulphate to barium sulphate. The sodium sulphide solution formed as a by-product in the precipitation can be returned and recycled. In the post-treatment, the precipitated barium sulphate is filtered off by means of a filter press, mechanically dewatered and dried. The treatment of the precipitate uses MSE filter presses, which are characterised by their solid, robust and high-quality architecture coupled with a high filtration quality and excellent dewatering results. The high dry matter content achievable with membrane filter presses makes it possible to reduce the downstream drying time and also the energy consumption. The final process step in the production of barium sulphate is grinding and packaging.
In cooperation with the polymer manufacturer PRO-ENTEC, MSE Filterpressen® has successfully dewatered the digestate of a biogas plant that is difficult to dewater. The conditioning of the sludge was carried out with polymers from PRO-ENTEC. The pilot test with a chamber filter press showed excellent solid-liquid separation results for the biosludge: high degree of biosludge separation (DM content in the filtrate less than 0.1%), nitrogen reduction in the filtrate up to 40%, phosphorus reduction in the filtrate, dry content of the filter cake up to about 30%.
The industrial use of bismuth vanadate constitutes a high-quality inorganic yellow pigment alternative to the bleach-containing pigments utilised until recently, which are classified as carcinogenic, mutagenic and reprotoxic substances according to the EU REACH regulation and are becoming increasingly less important. The large-scale production of crystalline bismuth vanadate is carried out, for example, by precipitation from a nitric acid bismuth nitrate solution and a vanadate solution. Here, the targeted hue and brilliance of the bismuth vanadate pigment is greatly affected by the precipitation conditions, e.g. concentration, temperature and pH ratios. The resulting suspension is separated from by-products in a mechanical solid-liquid separation process and the solids-free filtrate formed during the filtration process is separated off and recycled. The filtered bismuth vanadate filter cake is subjected to pigment scrubbing in a further step and then dried.
An essential and proven process component for the filtration of bismuth vanadate pigment suspensions is the filter press. Similar to the previously mentioned pigment dewatering and filtration processes, MSE filter presses offer increased customer value in the form of highly achievable pigment quality, increased energy efficiency, proven membrane filter plate and filter cloth technologies (close cooperation with renowned suppliers) and optimised, efficiently designed process parameters derived from our know-how.
For the technical production of boric acid, borate minerals, usually borax derived from coreite, are acidified with hydrochloric acid or sulphuric acid and then converted to B(OH)3. The boric acid present in the liquid phase is separated from the by-products and admixtures in a subsequent filtration and washing step, mainly calcium sulphate. An essential process component for the solid-liquid separation stage is the filter press. In order to meet the increasing requirements in terms of fineness, purity, cake washing effectiveness and consumption minimisation, MSE Filterpressen® offers tailor-made solutions aimed at maximum customer benefit. Our products contribute to increased filtration process productivity with their solid, rugged and high-quality architecture which is well-known in the marketplace.
Ceramic colours are temperature-resistant materials that are used to produce coloured coatings of silicate and for the fireproof colouring of ceramic materials. In a wet or dry grinding process, the corresponding raw materials are crushed, mixed and then annealed in tunnel kilns. After the firing process, the annealed product which is sintered into hard lumps, is wet ground. The pigments (up to approx. 10ym) must be filtered off using a washing process of soluble admixtures and inorganic salts. Separation units in the form of chamber or membrane filter presses are used here where the suspension of ground material is first extracted with water until the required specifications regarding purity and pigment quality have been achieved. The resulting filter cake solid is dewatered to a minimum of residual moisture and then thermally dried. Finally, the material is ground and packaged.
In this context, MSE filter presses, with the corresponding design-typical features for this application, enable high filtration speeds during dewatering of the washed pigments, a high filtration quality as well as very high dry matter contents (DM contents) of the filter cake solids and excellent economic results due to the low residual moisture. Raw materials for the production of ceramic pigments are iron oxide, tin oxide, quartz, calcite, chromium oxide, aluminium oxide, cobalt oxide, alkali chromates, alkali borates, but also vanadium, zirconium and rare earth oxides. Filter presses are also used for processing and dewatering the raw materials mentioned above.
Chromium oxide pigments are, chemically-speaking, oxides or oxide hydrates of trivalent chromium and non-toxic unlike hazardous chromium(VI) oxide. The most technically significant chromium oxide pigment is the chromium oxide green (Cr2O3). The technical manufacturing and preparation of chromium oxide pigments is carried out by the reduction of alkali chromates, preferably by the solid phase reaction, which is performed as a highly exothermic furnace process. The reducing agents used are carbon-containing compounds or sulphur. The reaction mixture, which still contains sodium sulphate and possibly unreacted chromate in addition to chromium oxide, is mixed with water, the chromium oxide pigment is filtered off as a suspension with the aim of a puncture-proof filter cake by means of pressure filtration, dewatered and the soluble accompanying salts are removed by washing with washing water.
Filter presses are used as a separation unit for the mechanical filtration of the pigment, which are of crucial importance in terms of achievable pigment quality, increased energy efficiency and high energy benefits throughout the manufacturing process. With their design-typical features and the exclusive and proven membrane filter plate technology in the treatment of chromium oxide, MSE filter presses offer high filtration rates and high filtration quality as well as a high dry matter content which is crucial for comprehensive production and can only be achieved with filter presses. In this context, a reduction of the downstream drying time and thus the energy consumption by more than 20% is possible.
Hydrothermal carbonisation (HTC) is a process where biomass is converted into biochar (HTC-coal) in an aqueous suspension at temperatures between 180-250 °C and elevated pressure.* The recovery of phosphorus, for example, after a hydrothermal carbonisation is the subject of current research (e.g. at the RWTH Aachen). The resulting waste biomass (e.g. sewage sludge) is thereby first mechanically dewatered conventionally (approximately 20% DM) and then converted to HTC-carbon by hydrothermal carbonisation (HTC) under pressure and elevated temperature (approx. 220 °C). The charred sludge (about 45% DM) is mechanically dewatered in a last step, with the aid of membrane filter presses to a dry solids content of about 60 to 80% DM and the puncture-resistant filter cake is then dried to the maximum required DM content depending on the application. The brown coal-like end product is used as an energy source but also for soil improvement or as a sorbent in waste water treatment.
Iron blue is a standard term for insoluble pigments based on cyano complexes of bivalent and trivalent iron. The industrial production of iron blue pigments takes place by the precipitation of complex iron (II) cyanides with iron (II) salts in an aqueous solution. The resulting white dough subsequently oxidises through the addition of sodium chlorate and hydrochloric acid to iron (III) hexacyanoferrate, the iron blue. The iron blue pigments are then freed from the soluble accompanying salts through repeated washing, dewatered and dried gently. Here, the treatment and dewatering of the iron blue pigments is done using a filter press, which is of crucial importance in the entire manufacturing process with regard to increased energy efficiency and energy benefits. With their design-typical features and the exclusive and proven membrane filter plate technology in the treatment of iron blue, MSE chamber and membrane filter presses offer high filtration rates and a high filtration quality as well as a high dry matter content that can only be achieved with filter presses. In this context, a reduction of the downstream drying time and thus energy consumption is possible.
In the industrial manufacturing and processing of iron oxides, iron sulphates are first dissolved in water, washed and the resulting material obtained as a suspension is filtered and dewatered with the aim of a puncture-proof filter cake by means of pressure filtration. In view of saving energy, of great importance here is the residual moisture content. MSE membrane filter presses provide all the functions and features required for this process. The iron oxide pigments are processed MSE membrane filter presses due to the high filtration and dewatering requirements, which are of crucial importance in terms of increased energy efficiency and high energy benefits throughout the manufacturing process. Our products are characterised by their design-typical features and the exclusive and proven membrane filter plate technology in the iron oxide treatment especially through high filtration rates and the high filtration quality and through the dry matter content that can only be achieved with filter presses. In this context, a reduction of the downstream drying time and thus the energy consumption by more than 20% is possible.
The industrial production of mixed-phase pigments (rutile and spinel pigments, 0.2 – 2ym), which are derived from other oxide pigments (e.g. titanium dioxide, iron oxide), takes place by reaction of finely divided metal oxides, hydroxides or carbonates in the solid state at temperatures between 800 °C and 1400 °C. After annealing, the mixed phase pigments are wet milled and filtered by washing the soluble companion salts (water consumption of up to 150 m3/t) that form in the ongoing solid-state reactions. The pigment produced as a suspension is then mechanically dewatered using special filter presses with the aim of producing a puncture-proof filter cake, then dried, ground again and packaged.
Similar to the previously mentioned pigment dewatering and filtration process, MSE filter presses offer increased customer value in the form of highly achievable pigment quality, increased energy efficiency, proven membrane filter plate and filter cloth technologies (close cooperation with renowned suppliers) and optimised, efficiently designed process parameters derived from our know-how. Energy cost savings in the downstream drying plants (reduction of the downstream drying time) are also possible, especially with regard to the achievable DM contents.
When cleaning containers and plants with different suspensions, the liquid phase is pumped off with vacuum trucks and discharged into containers for further treatment. Previously, the thin sludge was drained in suitable collection containers with cascade filling. The liquid phase was pumped off and professionally treated in the plant’s own neutralisation system. The solid phase was removed from the cascades at specific intervals. However, this solid phase is still cross-linked with approx. 70% water. In cooperation with a Daimler Chrysler team, which was specially put together with specialists to work on this problem, a new receiving station was developed, which clearly exceeds the values and throughput lines of the former plant.
The plant essentially consists of the receiving station for the vacuum trucks, a solids discharge, thin sludge tank with a thick slurry pump, buffer tanks, preparation and chamber filter press. The receiving station is fully automatic. The vacuum trucks empty the suspensions into the collecting trough. The solids separator conveys solids and/or foreign bodies into a container. The solids are mechanically dewatered as far as possible. After separation of the solids, the suspensions are pumped into buffer tanks. The buffer tanks serve as intermediate storage tanks in order to keep filtration with the MSE chamber filter press as low as possible and to accommodate large delivery quantities.
The pump-capable suspension is pressed with an MSE chamber filter press and the addition of small quantities of additives. A so-called filter cake with a residual water content of < 30% is achieved, which results in a significant cost reduction and minimised personnel effort.
Filter presses are used in the petrochemical industry in many chemical plant and refinery applications. Filtration is a fundamental step in the clarity process of many chemicals from iron hydroxide to ethylene glycol. The use of MSE filter presses guarantees the successful implementation of your project and, above all, the safe and efficient operation of your filtration plant – throughout its entire service life.
Membrane filter presses have the special feature that the resulting filter cake is mechanically pressed out and additionally dewatered in a squeezing operation after filtration and filter cake washing. The resulting higher dry matter content (DM content) generates a better dissolving behaviour of the filter cake. Our proven filter presses help to release the full value of your raw materials, resulting in high-quality end products. MSE filter presses are available with a fully automatic design for a fast cycle time and the associated high capacities.
In cold rolling mills, cold strips are subjected to a pickling process to produce flat products made from high quality steels. The pickling of aluminium, on the other hand, often serves as a pre-treatment for adhesive joints as well as before the anodising of aluminium surfaces in anodising plants. An essential plant and important process step in this manufacturing process is thus the pickling plant in a cold rolling plant, in which the hot strip pre-material (the solid burn-up on the surface produced by the hot rolling process) is first descaled in the pickling part and is then rolled to the customer’s desired final thickness in the coupled tandem mill. The pickling process that results during the striping process is regenerated to hydrochloric acid or sulphuric acid during regeneration and recycled. Regeneration and pickling are decoupled from the process side via a tank farm.
An essential process component of this plant is the filter press, which filters out and dewaters the fine scale residues with the aim of solids-free hydrochloric/sulphuric acid by means of pressure filtration. This forms a filter cake solid, which is then further processed and sold. This stripping treatment is due to the high degree of filtration requirements by an MSE chamber filter press. With their design-typical features, these are characterised in the hydrochloric and sulphuric acid treatment by high filtration rates and quality as well as an efficient configuration of the process which is optimised for the process.
Motor vehicles are generally mass=produced products with the highest quality standards. In every phase of production, only the best results are sufficient for a high-quality end product. So, it goes without saying that the highest demands are also placed on the cleaning of the body shells. After all, this is the basis for flawless painting. The purity of the cleaning baths has the highest priority. Before MSE developed the process for cleaning the phosphating baths using direct filtration in a filter press, complex process steps were necessary at this point. But lamella separators and sludge thickening with subsequent filtration are now a thing of the past in modern production plants. Direct filtration via MSE filter presses means consistent quality of the cleaning baths through permanent and uniform circulation of the baths via the filter press. With filtration times of several days as a rule, the personnel effort is just as low as the machine-related technical expenditure.
PHOSPHATING SLUDGE – UNDER CONSTANT CHANGE
With the development of direct filtration and its successful worldwide introduction in many automotive plants, the task was long not completed. The ever-increasing proportion of aluminium components in modern vehicle bodies presents us with continuous new challenges. The manufacturers of the chemicals used in the pre-treatment of body shells are also constantly developing their products further to meet the changing requirements. In cooperation with the manufacturers of chemicals and filter cloths, the successful process is constantly being further developed.
For the technical production of silicic acids, alkali silicate solutions (preferably soda water glass) are precipitated by the addition of mineral acid to form amorphous silicic acids and reacted in large stirred tanks at elevated temperature. In order to achieve the required end product quality, the resulting suspensions are filtered and the precipitation residues (silicate cake) remaining after filtration are freed from soluble salts (sodium sulphate) in a subsequent cake washing which result during the process. The sulphate content remaining in the filter cake can be adjusted by using this process depending on the application (0.2% to 0.8% sulphate). The membrane filter presses used in this context form the state of the art.
MSE filter presses offer a solid, robust and high-quality architecture, with the design-specific and process-technical features and the exclusive membrane filter plate technology, which ensures a high productivity of the filtration process. The high filtration quality as well as excellent dewatering results are further distinguishing features. Through subsequently drying, grinding and sieving, the packaged end product is finally ready for marketing. The high dry matter content achievable with the aid of membrane filter presses makes it possible to reduce the downstream drying time and also the energy consumption.
For the technical production of amorphous metal silicates, alkali silicate solutions (also preferably soda silicate) are precipitated to silicates by the addition of the corresponding quantity of calcium, magnesium or aluminium salt solutions and reacted in large stirred tanks at elevated temperature. The further treatment is carried out analogously to the precipitated silicic acid.
For the technical production of a high-purity raw brine, sodium-containing reaction products (NRP) are used to a large extent in the pre-separation of filter dusts, which serve as a raw material for the production of sodium carbonate due to their high degree of purity. The NRPs used in this process are extracted in an aqueous solution at a controlled pH value with the addition of defined additives, the resulting suspension is then fed to a filter press for mechanical solid/liquid separation and the liquid phase is separated from insoluble components such as heavy metal hydroxides, activated carbon and fly ash with the aim of a solids-free filtrate. The filtered raw brine then passes through an activated carbon stage in which organic components are separated. In ion exchange columns, the raw brine is finally cleaned of the remaining traces of heavy metal and subsequently recycled as the starting material for the new production of sodium carbonate using the Solvay process.
The filter cake formed is the material that is disposed of without exception as residual waste. The filter press is an essential component in the process of solid-liquid filtration. With their design-typical features, the MSE filter presses are characterised by high filtration rates and quality as well as an efficient configuration of the process which is optimised for this application. MSE Filterpressen® offer comprehensive and sophisticated filter press technologies and customer-oriented solutions to improve production, efficiency and end-product quality.
Red sludge or bauxite residue is a waste product which is an unavoidable companion in the extraction of aluminium oxide from ores containing aluminium (in particular bauxite) and, due to its alkalinity (pH values between 11 and 14), poses a serious environmental and disposal problem as well as a major hazard to groundwater. From a chemical point of view, the mixture formed and remaining during aluminium production according to the Bayer process consists mainly of iron oxides or hydroxides, titanium oxides, aluminium oxide residues, quartz sand, calcium oxide, sodium oxide and residual sodium hydroxide solution. At the end of the reaction time, the liquid phase (alkali percentage and dissolved calcium/sodium aluminates) is then transferred to a chamber filter press* where it is separated from the solid product mixture (calcium aluminate clay sludge (CATO)) and dewatered with the aim of obtaining a clear and solids-free filtrate and a solid filter cake.
The filter cake formed and present as the end product of the leaching process has a particularly large reactive surface and can be reused in a variety of ways. In this context, MSE filter presses, with the corresponding design-typical features and the exclusive and proven membrane filter plate technology in the red sludge filtration, offer high filtration rates and a high filtration quality as well as a high dry matter content that can only be achieved with filter presses. This is particularly important from an economic point of view.
Due to the varying composition, four categories can be named with regard to the possible application of bauxite residues:
- Recovery of main and secondary components: Iron, titanium, rare earth elements (SEE)
- Use as main raw material for the manufacture of products, e.g. cement
- Use of bauxite residue as a component in building materials, e.g. concrete, bricks, tiles; soil improvement
- Conversion of the residue into a useful product, e.g. by the Virotec process (Basecon Technology protected process)
Thus, all end products of the process are recyclable materials that are available both economically and environmentally neutral from the red sludge, which was previously regarded as a waste material.]]>
In the large-scale production of sodium carbonate (Na2CO3) using the Solvay process (also known as the ammonia soda process), the relatively poorly soluble sodium hydrogen carbonate is precipitated from an aqueous sodium chloride solution. This conversion is achieved by adding ammonia to a concentrated sodium chloride solution and then saturating it with carbon dioxide. Here, sodium hydrogen carbonate (sodium bicarbonate) precipitates, which in a further step, is mechanically separated from the resulting solid suspended matter (ammonium chloride solution), dewatered and then calcined to soda, e.g. in rotary drums/rotary kilns (approx. 200 °C). The carbon dioxide split off during calcination as well as the ammonia converted from the reaction of ammonium chloride (ammonium chloride) with calcium oxide or calcium hydroxide are returned to the chemical process.
The filter press is an essential component in the process of solid-liquid filtration. With their design-typical features, the MSE filter presses are characterised by high filtration rates and quality as well as an efficient configuration of the process which is optimised for this application. MSE filter presses offer comprehensive and sophisticated filter press technologies and customer-oriented solutions to improve production, efficiency and end-product quality. Due to the process, the production of soda also produces vast amounts of waste water (lime sludge), which must first be freed of the solids before disposal. The waste water is also cleaned with the aid of filter presses. The lime sludge is separated from the solid suspended solids with the aim of a solids-free filtrate and the clear filtrate (purified waste water) is then discharged.
To produce strontium chromate, the raw materials are dissolved separately in an aqueous solution and combined in a reactor. The starting materials dissolved in this way react with each other, forming a reaction product whose solubility is considerably lower than that of the starting material. Due to the high degree of filtration and dewatering requirements, the suspension is conveyed on chamber filter presses and mechanically filtered and dewatered with the aim of producing a puncture-proof strontium chromate filter cake.
MSE filter presses are characterised by their design-typical properties and the exclusive and proven membrane filter plate technology especially through high filtration rates and the high filtration quality and through the dry matter content that can only be achieved with filter presses. The subsequent washing process removes adhering residues (easily soluble reactant or reaction residues). The resulting and dewatered filter cake solid is dried again in lump form in drying ovens, ground and packaged. The dry matter content achievable with the membrane filter press reduces the downstream drying time and thus energy consumption by more than 20%.
In the automotive industry as well as in steel mills, tinning plants are required to refine the ultra-fine sheet metal into tinplate. The sheets undergo various treatments in the steel mill. The aim is to guarantee or increase the corrosion protection of the sheet after these processes have been completed. The residues resulting from the tinning process are fed to the filter press in a separate circuit with the aim of a solids-free filtrate and filtered out by means of solid/liquid separation. This electrolyte treatment is due to the high degree of filtration requirements by an MSE chamber filter press. With their design-typical features, MSE chamber filter presses are characterised in electrolyte treatment by high filtration rates and quality as well as an efficient configuration of the process which is optimised for the process in the application case. The tin sludge produced after the pressure filtration is then collected and fed to additional technical recycling. The filtered electrolyte is returned to the tinning process.
In the industrial production of titanium oxide (TiO2) is by far the most important white pigment. The finely ground and enriched titanium ore with concentrated sulphuric acid (up to 30%) is broken down into iron sulphate and titanium oxide sulphate and converted using the sulphate process (also called sulphuric acid process). The digestion cake is dissolved in water and the solution is purified. After the original filtration, the iron sulphate in solution is washed up and separated from the titanium oxide sulphate. This is followed by hydrolysis of the titanium oxide sulphate remaining in the solution, which precipitates as a poorly soluble titanium oxide hydrate and is separated. After several filtration processes, extensive washing and subsequent bleaching (to remove adhering higher-grade impurities), the titanium oxide hydrate is converted to pure white titanium dioxide in a large, rotatable tube furnace at 800 to 1000°C.
An essential process component for filtration across all process stages (chemically aggressive and non-aggressive filtration) is the filter press, which filters and dewaters the washed titanium dioxide by means of pressure filtration with the aim of producing a solids-free filtrate and a puncture-proof titanium dioxide filter cake. In view of the high degree of dewatering requirements with regard to a low residual moisture content and due to the required chemical resistance, this filtration is carried out using an MSE membrane filter press, which is equipped with proven membrane filter plate technologies. Due to the achievable DM contents, high energy costs are also saved by eliminating downstream drying processes (e.g. drum dryers).
For the technical production of vanadium, vanadium ores are converted into sodium vanadate (NaVO3) by adding sodium carriers (sodium chloride, sodium carbonate, sodium sulphate or sodium oxalate) at temperatures of approx. 850 °C in the rotary kiln. After leaching with water, filtration, acidification and drying, the vanadium vanadate is converted into vanadium (V) oxide*. In the solid-liquid separation stage, the vanadium salt solution is separated from by-products by means of filter presses. The chemical resistance of the materials used and the associated cake washing efficiency, which is necessary due to the mineral acid content of the slurry and analogous to most chemical processes, is of great and decisive importance here.
In order to meet these requirements, MSE Filterpressen® offers tailor-made solutions geared to the highest customer benefits. Our products contribute to a high productivity during the entire filtration process with the solid, robust and high-quality architecture known on the market as well as the membrane filter plate and filter cloth technology adapted and proven for this application. The resulting vanadium(V) oxide serves as a starting material for further vanadium compounds. A possible treatment is the reduction with calcium or aluminium to metallic vanadium. Most of the vanadium produced is marketed in the form of ferrovanadium or used as an alloying additive in steel production.
For the production of zeolite, alkali water glass is converted with a sodium aluminate solution in certain precisely defined ratios and under certain reaction conditions. In order to achieve the required degree of purity and end-product quality of the zeolite, the resulting suspensions are separated from the highly alkaline by-products in a complex, slightly tempered cake washing process and mechanically dewatered by using special filter presses with the aim of achieving a puncture-proof zeolite filter cake after the crystallisation process has been completed.
The dry matter content and the chemical resistance of the materials used, which are necessary due to the high alkalinity of the slurry, are of great and decisive importance. The material has been increased to a maximum with regard to the solid, robust and high-quality architecture of the MSE membrane filter presses used for this purpose and the selected and proven membrane filter plate technology. The washing solution and the clear filtrate are almost completely returned to the production process after the filtration process. The zeolites are sold as slurries or spray-dried. MSE filter presses guarantee maximum quality of the end products as part of a process component for zeolite production and with the aim of optimising energy consumption.
In industrial zinc production using electrolytic refining, the raw zinc oxide prepared by ustulation to zinc ore concentrate is dissolved in diluted sulphuric acid in a wet chemical process and impurities of more precious metals are precipitated by zinc powder. The electrolysis treatment of the zinc sulphate solution is then carried out using lead anodes and aluminium cathodes, whereby metallic zinc is deposited as a pure metal on the cathode. In this context, less noble by-products also go into solution, but without cathodic deposition. More noble minor elements precipitate as anode sludge (see application anode sludge). However, the electrolytic deposition of zinc from acidic solutions only works if the zinc salt solution is very pure (only then is the overvoltage of hydrogen so high that zinc separates out instead of hydrogen).
Filter presses are used to clean the zinc sulphate. The saturated zinc sulphate solution is filtered, washed and separated from the poorly soluble residues at elevated filtration temperatures. A high degree of cake washing efficiency at filtration temperatures of up to 90 °C and high resistance to chemically aggressive sludge is of decisive importance and a basic requirement for the architecture used and the selected filtration components such as filter plate and filter cloth materials. MSE Filterpressen® offer comprehensive and sophisticated filter press technologies and customer-oriented solutions to improve production, efficiency and end-product quality.
Mechanical solid/liquid separation stages with membrane filter presses are now standard worldwide for the large-scale production of azo dyes/pigments, disperse dyes and reactive dyes. A high degree of cake washing efficiency at filtration temperatures between 20 °C and 90 °C and a high chemical resistance against both strongly acidic and alkaline turbidities is of decisive importance and a basic requirement for the architecture used and the selected filtration components such as filter plate and filter cloth materials. MSE Filterpressen® offer you comprehensive and sophisticated filter press technologies and customer-oriented solutions to improve production, efficiency and end-product quality in the application area of pigments and dyes. Examples of applications for MSE filter presses are shown in the list.
Finely divided, surface-rich zinc oxide is a versatile chemical basic material which is produced in a wet-chemical process from zinc-containing salt solutions via the precipitation stage as zinc hydroxide or as basic zinc carbonate. The resulting precipitation product is separated from the mother lye in a solid/liquid separation stage, the filter cake formed is washed if necessary and converted into zinc oxide by subsequent dehydration/heat treatment (calcination). Products with high specific surfaces are manufactured by a gentle drying process. In order to meet the increasing requirements in terms of fineness, purity, effectiveness and consumption minimisation, MSE Filterpressen® offers tailor-made solutions aimed at maximum customer benefit. Our products contribute to increased filtration process productivity with their solid, robust and high-quality architecture which is well-known in the marketplace.