cpi

• Chemical engineering


  Branch of engineering concerned with the development and application of manufacturing processes in which chemical or certain physical changes of materials are involved
• Chemical engineer


  Concerned primarily with the design, construction, and operation of equipment and plants in which unit operations and processes are applied
• Unit processes


  The commercialization of a chemical reaction under such conditions as to be economically profitable
• Unit operations


  A physical change connected with the industrial handling of chemicals or allied materials
• Mechanical failures are seldom experienced unless there has been a previous corroding or a weakening by chemical attack on the material used for the construction of either the equipment or the building
• Common construction materials used by chemical engineers

  • Brick
  • Iron
  • Cement
  • Wood
  • Platinum
  • Tantalum
  • Silver
• Choosing the right material

  Requires knowledge of the strength necessary and the chemical resistance needed
• Continuous process


  Mainly used for large-scale processes
• Batch process


  Used when chemical manufacturing is on a small scale or when it is not adaptable to continuous procedures
• Chemical control: Analysis of incoming raw material


  The chemical manufacturer should know the character of the raw materials and set up strict quality specifications to assure the minimum or complete absence of certain undesirable impurities
• Chemical control: Process control

  An essential part of practically all manufacturing operations involving chemical change to avoid reactions getting out of hand
• Chemical control: Analysis of outgoing products


  To ensure the customer gets material which meets specifications and does not vary beyond predetermined limits
• Other general fundamentals in a chemical processing plant

  • Containers
  • Safety and fire protection
  • Patents
  • Research
  • Waste disposal
  • Growth and statistics
  • Miscellaneous aspects (plants location, competing processes, labor, sales, pilot plants, library)
• Process flow diagram (PFD)


  A graphical representation of a chemical process that displays the relationship between the different process units in a clear, concise manner
• Block flow diagram (BFD)


  The simplest form of a PFD that shows the major pieces of equipment and the process steps
• Process flow diagram (PFD)


  Provides more detail about the major equipment, subsystems, and process flow path than a BFD
• What is included in a process flow diagram

  • Equipment
  • Valves
  • Piping lines
  • Instruments
  • Centrifuges
  • Heat exchangers
  • Crushers
• Process flow diagram symbols - equipment

  • Compressor
  • Pump
  • Mixing
  • Mixing vessel
  • Heat exchanger
  • Cooling towers
  • Cooler
  • Furnace
  • Boiler
  • Tank
• Process flow diagram symbols - piping lines

  • Major pipeline
  • Major straight line
  • Process connection
  • Flange
  • Reducer
• Process flow diagram symbols - instruments

  • Indicator
  • Thermometer
  • Flow transmitter
  • Pressure transmitter
  • Pressure recorder
• Centrifuge


  A device whose function is to extract insoluble particles from a solution through spinning
• Heat exchangers


  Devices used for transferring thermal energy from one fluid or gas to another one
• Crushers


  Machines used to reduce the size of heavy rocks, stones and ores into a desired shape and form
• Piping & instrumentation diagram (P&ID)


  A detailed process flow diagram that includes more details about the process industry like pipes diameter including pipes types and identifications, valve types, control valve and interlocks and all the pipes flow i.e. vents, drain line special fittings tapping and sampling lines etc.
• Process and instrumentation diagram (P&ID)

  Detailed process flow diagram that includes more details about the process industry like pipes diameter including pipes types and identifications, valve types, control valve and interlocks and all the pipes flow i.e. vents, drain line special fittings tapping and sampling lines etc.
• Types of process flowcharts in chemical engineering

  • Block Flow Diagram (BFD)
  • Process Flow Diagram (PFD)
  • Piping & Instrumentation Diagram (P&ID)
• Process flow diagrams


  Provide an overview of the manufacturing process which includes equipment and process flow
• Difference between P&ID and PFD

  • P&ID shows all of the piping, valves, and other equipment that is used in a process, and the different inputs and outputs for each piece of equipment
  • PFD only shows the major pieces of equipment and doesn't show all of the piping
  • P&IDs can be much more detailed than PFDs
• Industrial waste waters present a complex and challenging problem to the chemical engineer
• Reasons why industrial waste waters present a complex and challenging problem

  • Moral and publicity obligations
  • Laws prohibiting and limiting the pollution of streams
• Industrial solutions for waste waters

  • Re-use of waste waters
  • Recovery of by-products to lessen the expenses of treatment
  • Pooling of waste to distribute the pollution or to effect the saving of neutralization costs
• Types of water used in a chemical plant

  • Surface water
  • Ground water
• Ground water


  • More suitable for cooling purposes because of its relatively low summer and winter temperature
  • Generally harder and may cause scale, and hence may interfere with the heat transfer
• Hardness


  • Usually expressed in terms of the dissolved calcium and magnesium salts calculated as calcium carbonate equivalent, CaCO3
  • Measured by titrating with a standard soap solution (frequently called soap hardness)
  • Common units used in expressing water analyses are parts per million (ppm) and grains per gallon (one grain per gallon = 17.1 ppm)
• Hard waters


  • Those containing objectionable amount of dissolved salts of calcium and magnesium (can be present as bicarbonates, chlorides, or sulfates)
  • These salts give insoluble precipitates with soap and form clogging scales with low thermal conductivities when used in boiler
• Types of hardness


  • Carbonate (temporary) - usually be greatly reduced by boiling, caused by bicarbonates of lime and magnesia
  • Non-carbonate (permanent) - requires the use of chemical agents, due to sulfates and chlorides of lime and magnesia
• Other water impurities


  • Suspended insoluble matter (classed usually as turbidity)
  • Organic matter
  • Color
  • Dissolved gases - carbon dioxide (largely as bicarbonates), oxygen, nitrogen, hydrogen sulfide (sulfur waters)
• Water conditioning


  • Another term is water softening, the process of removing excess mineral content from a water source
  • A commercial water softener system is an essential water pretreatment solution for industrial and commercial facilities in most areas of the country
• Water purification


  Usually refers to the removal of organic matter and microorganisms from the water
• Water softening processes


  • Ion Exchange
  • Zeolite Exchange
  • Organic Ion Exchange
  • Lime-soda Process
  • Phosphate Conditioning
  • Silica Removal
  • Deaeration
  • Water Purification
  • Municipal Water Conditioning
  • Industrial Water Conditioning