greener world A
needs the best practices Chematur Ecoplanning Oy is an engineering company having its basic roots in the big Finnish industrial conglomerates W. Rosenlew Ltd and Rauma-Repola Ltd. Its activities started in 1853. Ecoplanning’s process knowledge is based on more than 40 years’ experience and on more than 200 evaporation and crystallization plants e.g. caustic soda concentration in the chlor-alkali industry and various salts crystallization in the chemical industry. Ecoplanning also has a broad experience in the recovery of acids containing different kind of impurities, especially of sulphuric acid from the production of titanium dioxide or of the bleed acid from copper refinery. The company has a wealth of experience in the selection of suitable corrosionresistant materials such as special plastics, glass-lined steel, tantalum, titanium, nickel and impregnated graphite. Ecoplanning together with its skilled personnel and reliable sub-suppliers serves customers worldwide supplying new plants for purification and re-use of industrial effluents or plant upgrades in order to comply with today’s demanding environmental regulations. Being a member of the Chematur Group, the company utilizes the strength of financial and human resources by co-operating together with the parent company and its subsidiaries.
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Recycling - Ecology Traditionally, the acid used in processes from titanium dioxide to metallurgical production was neutralized and discharged into waterways or injected into deep wells. The other option was to sell the spent acid to fertilizer producers, but health concerns and the depressed fertilizer market have dried up this option, too. The best way to take care of this spent acid as well as all impurities is to use proven acid recovery technology and recycle it back to the process.
Efficient energy use Being energy efficient means both designing for efficiency and choosing the right technologies. As we design our processes and services to be energy efficient, our customers benefit from an improved efficiency and an increased business performance.
Tailor-made solutions We are specialized in providing customer-specific solutions. Our tailormade solutions are designed to customer’s product projects and they are developed in close co-operation with our customers according to their needs.
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We provide innovative solutions that are energy-efficient and environmentally compatible.
Innovativeness
Leader for greener growth. Our mission is to develop, design, deliver and construct on a world-wide basis, environmental friendly process plants for the chemical industry based on our proprietary technologies, complemented with licensed technologies. Chematur Ecoplanning Oy guarantees optimum solutions for your particular application based on experience and know-how that is specific to environmental technology and chemical plant engineering. In all respects, many years of experience guarantee expertise over a wide range of possible applications.
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Reliability
We want to be known for always keeping our promises. Our commitment to consistently deliver quality products and services gives customers the level of confidence they require.
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We value knowledge gained from both theory and experience.
Superior knowlegde
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Creating success
We work for and with our customers to identify and deliver solutions that exceed expectations, “Our customers’ success is our goal”.
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Applications
Industry segments Food Industry Ecoplanning’s processes are used in the food industry to concentrate sugar juice, vinasses and molasses. Ecoplanning also has experience in the purification and concentration of phosphoric acid.
Metallurgical Industry In the purification process of the electrolyte from the copper refinery, copper sulphate and nickel sulphate are recovered.
Pigment & Dye Industry In the sulphate process of manufacturing titanium dioxide pigment a vast amount of sulphuric acid is purified, concentrated and recycled through Ecoplanning’s processes.
Chlor-alkali Industry Caustic soda is typically a by-product from chlorine production. Modern chlorine processes using membrane technology are able to produce caustic soda with a concentration of 30-32 wt-% that often needs further concentration prior to shipping.
Fertilizer Industry Ecoplanning’s wide range of evaporation and crystallization solutions provides extensive capabilities for fertilizer production.
Chemical Industry Since the 1960’s Ecoplanning has provided evaporators and crystallizers for various inorganic and agricultural products. Applications vary from recovery of different effluent streams to high added value chemical products.
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Finland
Sweden
Denmark
Jordan
Germany China
Czech Republic
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Falling Film Evaporators
In falling film type evaporators, liquid flows downwards by gravity along the inner surface of vertical evaporator tubes. A short residence time of liquid on the heating surface and the ability to use a low temperature difference make falling film evaporators suitable for heat sensitive liquids. A falling film evaporator can be operated between 0 and 100% of the design capacity while still maintaining a good stability of the plant.
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Forced Circulation
In forced circulation type evaporators, the solution is circulated by a circulation pump through the heat exchanger tubes with high velocity from the bottom to the top. The vaporization takes place in the vapour head, where the vapour and liquor are separated by gravity and / or by centrifugal force. Forced circulation evaporators are suitable for liquids containing solid impurities or for crystallizing processes.
Evaporators
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Rising Film Evaporators
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Vapour Recompression Techniques
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In rising film type evaporators, the liquid moves by natural circulation from the bottom to the top of the tubes during which vaporization takes place. Rising film evaporators are of a fairly simple design leading to low investment and operating costs when compared to other evaporator types. Rising film evaporators require a higher temperature difference than other types and can be recommended only with relatively pure liquids.
Primary energy consumption can be reduced by compressing vapours either mechanically by blowers or thermally by steam. The compressed vapour can be reused as a heating media for further evaporation. Vapour recompression can be incorporated with falling film or forced circulation type evaporators. Vapour recompression is suitable for liquids having a low boiling point elevation such as dilute salt or acid solutions, for waste waters and in many food industry applications.
Specialist in Evaporation Ecoplanning has supplied more than 100 evaporation processes for various applications and techniques all over the world. Many of Ecoplanning’s evaporators are built for environmental reasons in order to decrease the volume of harmful effluent or for easier transport or to obtain a sellable product for example from dilute waste acid streams. The most suitable evaporator type is chosen case by case, taking into consideration numerous factors like the physical properties of the product (boiling point elevation, viscosity, sensitivity to temperature etc.), scaling or foaming tendency, impurity content etc. Many of the process liquids treated by Ecoplanning’s evaporators are highly corrosive and for this reason, the selection of construction materials is essential and influences the whole design process. In order to ensure optimum material selection and utilization, each evaporation process is tailor-made for every application.
Evaporation plants for / Sulphuric acid / Caustic soda / Phosphoric acid / Potassium chloride / Calcium chloride / Steep waters / Sweeteners and sugars / Molasses and vinasses / Waste waters / Fertilizer liquors
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Crystallization /10
Expert in Crystallization Crystallization from solution retains its importance as an industrial process because many materials are marketed in crystalline form. However, crystallization can also be used to separate dissolved impurities from process liquor allowing recirculation of valuable solvent. This may be done also for environmental reasons to prevent discharge of harmful solvent to waste water treatment. Supersaturated conditions in the crystallization vessel are required for crystallization. Depending on solubility properties, supersaturation can be achieved either by concentrating the solution, lowering solution temperature or by combining these two. Concentration can be realized either by single stage, or in order to save energy, multistage evaporation. The choice of crystallizer type depends on the crystallization behaviour of the solute such as crystal growth rate, nucleation rate, shape of solubility curve etc. Also product requirements, like desired crystal size and purity are parameters that are taken into consideration when selecting the most suitable process for the material in question. The processes can be either continuous or batch operated. Controlling the properties of the crystallized product is challenging, but Ecoplanning’s experience of nearly one hundred crystallizing processes gives a solid background in designing reliable and easy-to-use processes for customers all over the world.
Crystallization plants for / Ammonium sulphates / Ferrous sulphates / Sodium sulphates / Nickel sulphates / Copper sulphates / Potassium sulphates / Sodium chloride / Sodium chlorate
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In forced circulation crystallizers, crystallization occurs during evaporation and it is followed by slurry handling and solid-liquid separation. This type of crystallizer suits a wide range of salts that are crystallized by evaporation but limits the possibilities to control crystal size or crystal size distribution.
Circulation Crystallizer
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Draft Tube
In draft tube crystallizers, the draft tube design provides optimum agitation for the process. This type of crystallizer can be used for evaporation crystallization or for evaporative cooling crystallization and be operated either as a batch or continuous process.
Crystallizer
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Draft Tube Baffle Crystallizer
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Evaporative
Cooling Crystallizer
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In draft tube baffle crystallizers, the crystals are separated from the liquid in the baffle area before the liquid is heated in the heat exchanger. This gives a heating circulation relatively free of crystals; only very small crystals and nuclei will follow the mother liquor to the heat exchanger and these are dissolved during heating. The draft tube baffle crystallizer allows crystal growth control by removing the fine crystals from the liquid and thus the preferred crystal size and crystal size distribution are achieved.
In evaporative cooling crystallizers, cooling is achieved by lowering the pressure which causes flashing. The crystallization vessel can be either a simple agitated tank or a draft tube type vessel that can be operated as a batch or continuous process. Evaporative cooling crystallizers can be used for liquids having strong scaling or fouling potential because there are no heat exchange surfaces.
In surface cooling crystallizers, cooling is achieved either in a separate heat exchanger or with cooling coils in a crystallization vessel. Surface cooling crystallizers can be operated as a batch or continuous process but the former is preferred due to scaling and crystal formation on cooling surfaces.
Cooling Crystallizer
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Acid recovery /12
Superior in Acid Recovery Recovering sulphuric acid is a field that has made Ecoplanning a renowned name in the chemical process industry. It is a field that combines Ecoplanning’s core areas of expertise, evaporation and crystallization, but it also requires a strong experience in solid-liquid separation and use of special construction materials such as plastics, graphite, silicon iron and special alloys. This technology is widely used in processes especially within the titanium dioxide and metallurgical industry but also in other branches of the chemical industry. In the titanium dioxide (TiO2) industry alone, more than 4’000’000 tons of spent acid is processed with Ecoplanning’s plants annually. This corresponds to 1’900’000 tons of evaporated water annually. Spent acid treatment in the TiO2 industry includes crystallization, removal of copperas together with other impurities and concentrating the acid to the appropriate level to be used in the digestion phase of the TiO2 process. In the metallurgical industry, acid recovery is used in copper smelters purifying electrolyte from tankhouses and producing copper sulphate and nickel sulphate. After purification, acid is returned to the main process while recovered sulphates are valuable products. Ecoplanning’s acid recovery technology is also used to purify and concentrate weak wash acid from the sulphuric acid plant. This application includes acid concentration and simultaneous precipitation of metal salts that are filtered out from the concentrated acid.
Technology
Typically the diluted spent acid concentration varies from 5 to 25% and the desired final concentration from 50 to 70%. For this duty a multistage, normally two or three stage vacuum evaporation is the optimal solution. Depending on the acid properties, either falling film or forced circulation evaporation may be chosen. At the final concentration the solubility of most dissolved metals is reduced for precipitation and they may be separated from the mother liquid by filtration. In some cases the final concentration needs to be even higher to meet the process requirements. To reach the final concentration of 80 or even 90% more evaporation stages are required – typically an additional one or two stage evaporation. Ecoplanning has a long history and excellent knowledge of selecting the adequate materials for different acids in various concentrations and temperatures. Typical construction materials are different plastics, various stainless steels, graphite, zirconium, silicon iron and titanium. In the high concentration even more exotic alloys are needed, like niobium, tantalum, etc.
CASE: Manufacture of titanium dioxide Production of titanium dioxide from ilmenite or slag results in the formation of spent acid containing 20-25% sulphuric acid and 10-15% metal salts. Ecoplanning’s spent sulphuric acid recovery plants use a forced circulation evaporation process in which the spent acid is concentrated from 20% H2SO4 up to over 90%. The process consists of pre-concentration, ageing, filtration and final concentration units.
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Chemical engineering &
ecological competence
The Group began its chemical engineering activities in the early 1930’s and is today a solid and versatile engineering Group, equipped with state of the art design systems. The Chematur Group companies have supplied more than 1100 plants to customers worldwide. The companies can carry out any scope of your project, from licensing of own proprietary technologies to turnkey contracts. The basis of Group’s worldwide activities is engineering and allied services for process plants.
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Polyurethane Chemicals
Chematur Technologies AB / Sweden
The Polyurethane Chemicals business area comprises technologies for Nitrobenzene (NB), Aniline, Methylenediphenylamine (MDA), Methylenediphenyldiisocyanate (MDI), Dinitrotoluene (DNT), Toluenediamine (TDA) and Toluenediisocyanate (TDI), all necessary subsystems and Waste Treatment processes.
Acid Treatment
Chematur Engineering AB
The Acid Treatment business area comprises technologies for the treatment, concentration and recycling of sulphuric, nitric and hydrochloric acid.
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Evaporation & Crystallization
Chematur Ecoplanning Oy
The business area comprises technologies for concentration and purification of acids, evaporation units for sulphuric and phosphoric acids, caustic soda, potassium chloride, etc., and also crystallization plants for a number of nitrates, sulphates, chlorides/chlorates and phosphates.
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Chematur Group Plinke GmbH / Germany
Nitric Acid The Nitric Acid business area comprises the following technologies: Ammonia, Nitric Acid, Ammonium Nitrate (AN), Urea liquid or granules and UAN solutions.
Weatherly Inc. / USA
IBI Chematur Ltd. / India
Hydrogen Peroxide Chematur can supply plants for Chemical and Technical grade Hydrogen Peroxide.
Miscellaneous The Miscellaneous business area comprises the following technologies: Explosives and propellants. Supercritical Carbon Dioxide Technology and Biomass Technology.
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Chematur Ecoplanning Oy Pohjoisranta 11 F P.O. Box 78 FI-28101 Pori, FINLAND Tel: +358 (0)2 6240 200 Fax: +358 (0)2 6240 290 www.ecoplanning.fi