{"id":4293,"date":"2021-12-14T06:26:53","date_gmt":"2021-12-14T06:26:53","guid":{"rendered":"https:\/\/paramountlimited.com\/?page_id=4293"},"modified":"2024-09-25T11:56:10","modified_gmt":"2024-09-25T11:56:10","slug":"products_thermal-equipments-packages","status":"publish","type":"page","link":"https:\/\/paramountlimited.com\/?page_id=4293","title":{"rendered":"PRODUCTS_Thermal Equipments & Packages"},"content":{"rendered":"\t\t
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Thermal Equipments & Packages<\/p>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t

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Shell & Tube Heat Exchangers<\/h2>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t
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Heat exchangers are equipment used for transfer of heat.<\/p>

Paramount designs and manufactures shell and tube heat exchangers for the refinery, petrochemical, fertilizer & chemical industries.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t

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Following services are provided by Paramount on heat exchanger design \/ engineering.<\/p>

  • Develop new design using HTRI software which facilitates optimum and reliable design<\/li>
  • Simulate or rate existing exchangers for checking adequacy for new operating conditions<\/li>
  • Study the exchangers for fouling or malfunctioning<\/li>
  • Carry out vibration analysis for newly designed exchangers or existing, exchangers which are experiencing problem of vibration<\/li>
  • Develop mechanical design and fabrication drawings as per ASME\/ TEMA<\/li><\/ul>

    Paramount has ASME approved shop for the manufacture of shell & tube heat exchangers.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t

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    Multiple Effect Evaporator System<\/h2>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t
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    Evaporator differs from crystallizers in which evaporation is concerned with concentrating a solution rather than producing or building crystals. Evaporation is distinguished from drying giving always liquid residue.<\/p>

    Paramount offer multiple effect evaporator as stand alone process unit and also for treatment of RO concentrates to achieve zero liquid discharge in Wastewater treatment plant.<\/p>

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    Paramount designs and supplies a wide range of Evaporator such as single effect and multiple effects as per the needs of various process industries which are as follows:<\/strong><\/p>

    • Vertical Tube Evaporator
      o Falling Film
      o Rising Film<\/li>
    • Forced Circulation Evaporator<\/li>
    • Horizontal Tube Evaporator<\/li>
    • Plate Type Evaporator<\/li>
    • Natural Circulation Evaporator<\/li>
    • Flash Evaporator<\/li><\/ul>

      Paramount offers superior technology in the field of Multiple effect evaporator with specific thrust on Heat transfer, Vapor liquid separation & efficient utilization of energy.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t

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      The superior expertise of Paramount in Evaporation has following features:<\/strong><\/p>

      \u2022 Pure Condensate recoveries
      \u2022 Higher Salt recoveries
      \u2022 Higher thermal efficiencies by employing minimum scope of steam
      \u2022 Minimum Operating cost by using Mechanical Vapour Recompression (MVR) & Thermal Vapour Recompression (TVR)
      \u2022 Optimum Thermal design using software like HTRI & Aspen<\/p>

      Paramount offers Application for Evaporator in following Industries:<\/strong><\/p>

      \u2022 Chemical industries
      \u2022 Pharmaceutical
      \u2022 Biotechnology
      \u2022 Food & Dairy
      \u2022 Beverage industries
      \u2022 Environmental applications<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t

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      Waste Heat based Evaporation System<\/h2>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t
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      Industrial processes like Reverse Osmosis plant generate liquid effluent containing a high amount of inorganic soluble salts. Conventionally, wastewater containing high soluble impurities (dissolved solids) cannot be disposed of to water bodies. Methodologies followed are<\/p>

      • Conventional methods employ the high dissolved solids effluent is mixed with other dilute wastewater streams, before disposal, to meet disposal standards.<\/li>
      • In many cases, the soluble impurities are precipitated by using chemicals.<\/li><\/ul>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t
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        To achieve the concept of \u201czero discharge\u201d, the wastewater with high dissolved solids is treated using evaporator \/ RO technology where the liquid fraction of the wastewater is recovered in the form of water, which may be reused, and impurities present in the wastewater are collected separately as inert solids\/ concentrate. Even though the evaporation\/ RO technology provides a proven remedy for treatment of wastewater with high dissolved solids, it is used on a limited scale because of:<\/p>

        \u2022 High cost of equipment
        \u2022 High cost of energy for its operation
        \u2022 Complex operation requiring skilled manpower and major plant automation<\/p>

        Paramount provides an innovative concept of using \u201cQuench\u201d, a proprietary compact design for evaporating water from wastewater containing a high level of dissolved solids (50,000-55,000 ppm). This concept works to optimize and utilize the waste heat of the flue gases generated from the power plant\/ incinerator units.<\/p>

        In normal practice, a quench is used to cool the hot gas by having a direct contact water spray to reduce the gas temperature. Water is evaporated and converted to steam. This concept is based on evaporative cooling. The gas is further treated, as the case may be, depending upon the process. This concept of evaporative cooling is utilized from a different perspective (i.e. to evaporate the water using the waste heat rather than the conventional concept of cooling the gases with water).<\/p>

        This would result in the concentration of wastewater in the form of the slurry, containing suspended solids, generated due to the presence of high TDS and evaporation of water, which can be centrifuged to form a disposable cake. The centrate from the centrifuge is sent back to the quenching system for further evaporation. The cooled flue gases with water vapours can be discharged to the atmosphere through a stack.<\/p>

        This innovative concept was also presented to the Ministry of Environment and Forest (MOEF) and has been accepted.<\/p>

        This approach also helps to achieve a reduction in the initial cost of the plant including extremely low operating cost.<\/p>

        Comparison of Waste heat based Evaporator System with conventional Evaporator (Multiple effect) systems:<\/p>
        Sr. No.<\/span><\/div><\/td>
        Features<\/div><\/td>
        Evaporator System<\/div><\/td>
        Quench System<\/div><\/td><\/tr>
        1<\/div><\/td>
        Type of System<\/div><\/td>
        Multiple Effect Evaporator using steam as source of Heat<\/span><\/div><\/td>
        Flue Gas Quenching System to evaporate the water using waste heat in flue gases<\/div><\/td><\/tr>
        \u00a0<\/td>\u00a0<\/td>\u00a0<\/td>\u00a0<\/td><\/tr>
        2<\/div><\/td>
        Type of Operation<\/div><\/td>
        Complicated operation as it requires operation of lot of pumps, reactors and is highly instrumented<\/span><\/div><\/td>
        Very simple to operate as only four simple equipment needs operation<\/div><\/td><\/tr>
        \u00a0<\/td>\u00a0<\/td>\u00a0<\/td>\u00a0<\/td><\/tr>
        3<\/div><\/td>
        Operating Personal Requirement<\/div><\/td>
        Highly skilled operating staff conversant with process plant operation<\/span><\/div><\/td>
        Skilled operating staff with normal operating skills<\/div><\/td><\/tr>
        \u00a0<\/td>\u00a0<\/td>\u00a0<\/td>\u00a0<\/td><\/tr>
        4<\/div><\/td>
        Flexibility W.R.T. To Turn Down and Change in Effluent Characteristics<\/div><\/td>
        Less flexibility as the plant requires lot of controls due to change in effluent characteristics and turn down<\/span><\/div><\/td>
        No change in plant operating parameters are required even if there is a major change in plant capacity and effluent characteristics<\/div><\/td><\/tr>
        \u00a0<\/td>\u00a0<\/td>\u00a0<\/td>\u00a0<\/td><\/tr>
        5<\/div><\/td>
        Flue Requirement<\/div><\/td>
        Envisages Installations of a new Boiler for meeting system\u2019s steam requirement which would use fuel for steam production<\/span><\/div><\/td>
        Steam Boiler is not required and hence does not envisage burning of fuel<\/div><\/td><\/tr>
        \u00a0<\/td>\u00a0<\/td>\u00a0<\/td>\u00a0<\/td><\/tr>
        6<\/div><\/td>
        Reliability W.R.T.<\/div><\/td>
        Good<\/span><\/div><\/td>
        Very High<\/div><\/td><\/tr>
        \u00a0<\/td>\u00a0<\/td>\u00a0<\/td>\u00a0<\/td><\/tr>
        7<\/div><\/td>
        Turn Down Possible<\/div><\/td>
        Up to 30% max.<\/span><\/div><\/td>
        As low as 10%<\/div><\/td><\/tr>
        \u00a0<\/td>\u00a0<\/td>\u00a0<\/td>\u00a0<\/td><\/tr>
        8<\/div><\/td>
        Power requirement<\/div><\/td>
        15 \u2013 17 KW\/M3<\/sup><\/span><\/div><\/td>
        1.5 \u2013 1.6 KW\/M3<\/sup><\/div><\/td><\/tr>
        \u00a0<\/td>\u00a0<\/td>\u00a0<\/td>\u00a0<\/td><\/tr>
        9<\/div><\/td>
        Steam Requirement<\/div><\/td>
        300 \u2013 350 kgs\/m3<\/sup><\/span><\/div><\/td>
        Not required<\/div><\/td><\/tr>
        \u00a0<\/td>\u00a0<\/td>\u00a0<\/td>\u00a0<\/td><\/tr>
        10<\/div><\/td>
        Cooling Water Requirement<\/div><\/td>
        Yes<\/span><\/div><\/td>
        No<\/div><\/td><\/tr>
        \u00a0<\/td>\u00a0<\/td>\u00a0<\/td>\u00a0<\/td><\/tr>
        11<\/div><\/td>
        		Space Requirement<\/td>
        More<\/span><\/div><\/td>
        Less<\/div><\/td><\/tr>
        \u00a0<\/td>\u00a0<\/td>\u00a0<\/td>\u00a0<\/td><\/tr>
        12<\/div><\/td>
        Quality of End Product (Cake) Generated<\/div><\/td>
        Cake with 75 \u2013 80% solids<\/span><\/div><\/td>
        Comparable<\/div><\/td><\/tr>
        \u00a0<\/td>\u00a0<\/td>\u00a0<\/td>\u00a0<\/td><\/tr>
        13<\/div><\/td>
        Any other Salient Feature<\/div><\/td>
        High Maintenance Cost due to cleaning requirement of scales formed on tubes<\/span><\/div><\/td>
        Very low maintenance cost due to less number of equipment which are simple to operate and does not require de-scaling<\/div><\/td><\/tr><\/tbody><\/table>

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        The main Application of heat transfer mechanisms in a surface condenser is the condensing of saturated steam or Vapour on the outside of the tubes of the condenser which is done by circulating Chilled water or Cooling water inside the tubes of the condenser.<\/p>

        Due to the fact that a surface condenser operates under vacuum, non-condensable gases will migrate towards the condenser. The non-condensable gases consist of mostly air that has leaked into the cycle from components that are operating below atmospheric pressure.<\/p>

        These gases can also result from caused by the decomposition of water into oxygen and hydrogen by thermal or chemical reactions.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t

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        These gases must be vented from the condenser for the following reasons:<\/p>

        The gases will increase the operating pressure of the condenser. Since the total pressure of the condenser will be the sum of partial pressures of the steam and the gases as more gas is leaked into the system, the condenser pressure will rise. This rise in pressure will decrease the turbine output and efficiency.<\/p>

        • The gases will blanket the outer surface of the tubes. This will severely decrease the heat transfer of the steam to the circulating water. Again, the pressure in the condenser will increase.<\/li>
        • The corrosiveness of the condensate in the condenser increases as the oxygen content increases. Oxygen causes corrosion, mostly in the steam generator. Thus, these gases must be removed in order to extend the life of cycle components.<\/li><\/ul>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t
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          Surface Condensers prima facie are the generalized terms of a Water Cooled Shell and Tube Type Heat Exchangers that will utilize the heat of a motive liquid or gas to cool the receptive water, or in other words cool the flowing liquid.<\/p>

          Disposal of contaminated water is of growing concern in process operations. Where an ejector system is drawing in contaminants, a condenser that discharges directly to the drain may not be used. For such applications, ejectors using surface condensers are used. The surface condenser prevents discharge to the drain and permits recovery or treatment of undesirable wastes.<\/p>

          A steam jet ejector system with surface condensers normally requires more motive steam and condensing water than the one with direct contact condensers, and is the most expensive.<\/p>

          Key Advantages :<\/strong><\/p>

          \u2022 Decades of design and manufacturing experience
          \u2022 Compliance with HEI, ASME, PED and other design codes and engineering standards as per project requirements
          \u2022 Wide range of sizes
          \u2022 Experience to handle exotic and optional materials and configurations
          \u2022 Provides individual equipment and consolidated packages
          \u2022 Erection and Commissioning assistance and service<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t

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          Thermosyphon reboilers require pumping of the column bottoms liquid into the reboiler. Natural circulation is obtained by using the density difference between the reboiler inlet column bottoms liquid and the reboiler outlet liquid-vapor mixture to provide sufficient liquid head to deliver the tower bottoms into the reboiler. Thermosyphon reboilers are more complex than kettle reboilers and require more attention from the plant operators. There are many types of thermosyphon reboilers including vertical, horizontal, once-through or recirculating.<\/p>

          Thermosyphon reboilers play a wide role in the chemical industry, which provides a simple, low maintenance design for distillation tower reboiler system. The thermosyphon reboiler contains the two endearing qualities of the evaporator, namely mechanical simplicity and operation in the nucleate boiling regime with its attractive high fluxes. These reboilers require rational design procedure as several flow patterns manifests during the heat transfer to a flowing two phase boiling mixture, which in-turn depends on upon the flow rates, physical properties of the components, pipe diameter and orientation. The circulation rate, heat-transfer rate and pressure drop all are interrelated, and hence, iterative design procedures must be used.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t

          \n\t\t\t
          \n\t\t\t\t\t\t
          \n\t\t\t\t
          \n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\"\"\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t
          \n\t\t\t\t\t\t
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          Table 1: Advantages and Disadvantages of thermosyphon reboiler<\/strong><\/p>

          Advantages:<\/strong><\/p>

          \u2022 Cheapest reboiler installation in terms of capital and operating cost
          \u2022 Permits simple, compact piping arrangement
          \u2022 Provides excellent thermal performance<\/p>

          Disadvantages:<\/strong><\/p>

          \u2022 Not suitable for viscous or solid bearing fluids
          \u2022 More heat transfer area required for vacuum operation
          \u2022 Not specified for pressure below 0.3 bar
          \u2022 Column base must be elevated to provide the hydrostatic head required for the thermosyphon effect.
          \u2022 This increases the cost of the column supporting structure.<\/p>

          Features of Construction<\/strong><\/p>

          In thermosyphon reboilers, performance is determined by the interrelated thermal and hydraulic characteristics, of the reboiler and the interconnecting piping. Circulation is established through the reboiler by the difference between the hydraulic head of the liquid in the column and of the two phase mixture in the reboiler. Raising the liquid level in the column, relative to the reboiler increases this difference in hydrostatic head and thus increases the rate at which the fluid to be vaporized flows through the reboiler.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t

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          Falling Film Evaporators<\/h2>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t
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          \n\t\t\t\n\t\t\t\t\t\t<\/span>\n\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t
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          The Falling Film Evaporators can be operated with a low temperature difference and since the product residence time is very less, they are best suited for liquids which are temperature sensitive, have a high rate of specific heat transfer, particularly for non-crystalline solutions. Having low liquid holding volumes, the falling film evaporators are very easy to operate, clean and are extremely sturdy, thus the most frequently used types.<\/p>

          Caution must be used to ensure a continuous film wetting rate and to prevent nucleate boiling, otherwise the rate of heat transfer will fall off dramatically, and the rate of fouling on the heat transfer surface will increase.<\/p>

          In falling film evaporators the liquid product (A) usually enters the evaporator at the head (1) of the evaporator. In the head, the product is evenly distributed into the heating tubes. A thin film enters the heating tube are it flows downwards at boiling temperature and is partially evaporated. In most cases steam (D) is used for heating the evaporator. The product and the vapor both flow downwards in a parallel flow. This gravity-induced downward movement is increasingly augmented by the co-current vapor flow. The separation of the concentrated product (C) form its vapor (B) is undergoing in the lower part of the heat exchanger (3) and the separator (5)<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t

          \n\t\t\t
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          \n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\"\"\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t
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          \n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\"\"\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t
          \n\t\t\t
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          A: Product
          B: Vapor
          C: Concentrate
          D: Heating Steam
          E: Condensate
          1: Head
          2: Calandria
          3: Calandria, Lower part
          4: Mixing Channel
          5: Vapor Separator<\/p>

          Falling film evaporators can be operated with very low temperature differences between the heating media and the boiling liquid, and they also have very short product contact times, typically just a few seconds per pass. These characteristics make the falling film evaporator particularly suitable for heat-sensitive products, and it is today the most frequently used type of evaporator.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t

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          Falling film evaporators are used extensively in chemical process industry, food and paper industry. Due to the absence of static head effect caused by liquid column as in other types of evaporators, evaporation can take place at very small effective mean temperature differences. The temperature difference is typically between 3 – 8C. This is significantly less than in other devices used for evaporation, e.g. forced reboilers or kettle evaporators, here the effective mean temperature difference is between 15 a 30C. The film heat transfer coefficients are in general high and characterised by surface boiling.<\/p>

          The absence of hydrostatic head allows this type of evaporator to operate at very low absolute pressures.<\/p>

          Product residence time can be very short, especially in one through the operation. This characteristic of short retention time low operation pressure and small required effective mean temperature differences makes this type of evaporator particularly suitable for concentration of heat sensitive liquids. The absence of nucleate boiling under normal operation conditions and low temperature differences reduces also possible fouling tendencies.<\/p>

          The flow pattern can be characterised as a liquid annulus with vapour core.<\/p>

          Conclusion:<\/strong><\/p>