MATERIAL HANDLING AND STORAGE :

Storage

Every process plant requires adequate storage facilities for raw materials. Intermediate products, final products, recycle materials, off-grade materials, fuel etc. The requirement may be during the normal course of operation or, for temporary procurement or emergency delivery during plant shutdown so that the normal cycle of the plant remains unaffected.

Bulk storage and handling must be considered for any high volume operation that uses large quantities of standard products. It has advantages of a lower basic cost for the material purchase, a lower plant ‘shrinkage’ loss and a saving in the plant floor space as material can be stored outdoors in tanks. However it has a big disadvantage in the form of the huge capital investment required. Also there may be a loss in the flexibility of operations. There is always a risk of contamination of tank by a material of different grade or type.

Closed cylindrical or spherical tanks, to prevent the escape of volatile matter and minimize contamination generally handle bulk storage of liquid. Since safety is an important consideration in storage tank design, the Indian Petroleum Institute and The National Fire Petroleum Association, Publish rule for safe design and operation. Floating roof tanks are used to conserve valuable products with vapor pressure below atmosphere. While products with higher pressure must be stored in vapor tight tanks, capable of withstanding internal pressure. If flammable liquid are stored in vented tanks, flame arresters must be installed in all opening except connections below liquid level.

Gases are stored at atmospheric pressure in wet or dry-seal gas-holders. The wet-gas holder maintains a liquid seal of water or oil between the top movable inside tank and the stationary outside tank. In the dry-seal holder, the seal between the two tanks is made by means of means of a flexible rubber or plastic curtain. Recent developments in bulk natural gas-product storage show that pumping the gas into underground strata is cheapest method available. High-pressure gas is stored in spherical or horizontal cylindrical pressure vessels.

Handling

Material handling equipment is generally divided into two continuous and batch types and into a class for the handling of liquids, solids or gases. Liquids and gases are handled by means of pumps and blowers, in pipes

and ducts, and in containers such as, drums, cylinders and tank cars. Conveyors, bucket elevators, chutes, lift trucks and pneumatic systems may handle solids. The selection of materials handling depends upon the cost, the work to be done and the ease of operations and the efficiency achievable.

Factors that must be considered in selecting such equipment are as follows.

1. Chemical and physical nature of materials being handled.2. Type of environment and the distance through which the materials

have to be transported.3. Quantity of material moved per unit time.4. Nature of feed and discharge of materials-handling equipment.5. Continuous or intermittent nature of operations.

Since the industry in question is petroleum one, extreme care should be taken to prevent any possibility of spark generation, static electricity etc. that may lead to chances of fire. The tanks should each be grounded to prevent static electricity generation. While storing/handling liquids in tanks, care should be taken that they are not sent in from great heights to impinge directly upon the material underneath. Else, they should be sent in by the sides of the tanks or using a support of a stick-type equipment. Spark-resistant tools must be used. Any type of heating equipment should not be permitted in the area where inflammable fluids may be stored. All electrical switches, wiring should especially be properly insulated and in good condition in the vicinity of the sensitive areas.

The storage should be kept clean, free from oily rags, unused or old equipment. When filled drums or other containers are stored indoors, they should be stored in non-combustible, well-ventilated structures. All storage areas should be isolated from all sources of open flame, well posted with signs prohibiting smoking, and adequately equipped with fire extinguishing systems.

All tanks should have a vent pipe or sufficient area to permit escape of air and vapors during filling operations. Flame arresters should be fixed at the end of the vent pipe. The vents should terminate outdoors above roof-level to prevent contamination of workroom air. Each container should carry an identification level containing the following information-name and address of manufacturer, quality in kilograms or liters.

Lube oil base stock

Lubricants can deteriorate in storage, usually as a result of one of the following causes:1. Contamination, most frequently dirt and water2. Exposure to excessively high and low temperatures

Some contaminated or deteriorated lubricants can be reconditioned for use, while others must be degraded to inferior applications, destroyed or otherwise disposed of. In addition, portions of some contaminated products may be salvaged for use. The decision of which course of action to follow depends on such factors as the amount of product involved and its value compared to the cost of reconditioning or salvaging, the type and amount of contaminant present, the degree of deterioration that has occurred, and the effect of the contamination or deterioration on the functional characteristics of the product in the target application(s).

Contamination

The easiest way to control and particularly exclude contamination is to avoid using practices that risk exposing the lubrication to the environment and surfaces/objects that bear various forms and types of contaminants. Among other things, this guideline is designed to offer practical advice on how to exclude and monitor contaminants of various types from bulk lubricants in storage and handling. Contamination of lubricants is one of the most significant factors affecting the storage stability and service life of bulk oils. Common types of contamination are discussed below:

Condition of Storage and Handling equipment:Contamination of newly commissioned storage and handling equipment include preservatives, paint, moisture, rust particles and fabrication debris such as dust, dirt, or welding spatter, machining swarf, drill turnings, blasting sand and casting sand. To avoid contamination of bulk lubricants, appropriate care must be taken during manufacture, assembly, installation, servicing, repair, and conditioning of tanks and equipment. Before use, storage tanks should be thoroughly cleaned, scale-free and treated internally with a protective coating or sealant that is compatible with the lubricants these surfaces will contact. Tanks and vessels should be carefully dried and cleaned before they are charged with a lubricant to be stored.Solid ContaminationSolid contamination includes the additive residue (byproduct of degraded additives), paint chips, rust particles, and weld splatter that may pre-exist within the tank when first commissioned. Solid contaminants can also enter the tank through the breathers, inspection hatches, clean-out portals and through transfer hoses when filling the tank.

Liquid ContaminationMoisture, solvents, fuels, and other incompatible lubricants are harmful contaminants as well. Entrained water promotes base oil degradation and additive depletion. Dissolved, emulsified and free water all pose potential risks. In additions to distress imposed by water on additives and base oil oxidation, free water in bulk storage vessels provides a habitat for microbial contamination which is corrosive and harmful to lubricant performance properties. Lubricants in storage are most prone to become contaminated

with water from headspace condensation. There are many other sources of water as well. Emulsified water has a tendency to also impair air release properties of oil. When air fails to detrain (release air to the headspace) a common consequence is oil oxidation.

Thermal Degradation of LubricantsMost good quality synthetic and conventional mineral oils are not affected by storage temperatures below 120°F (49°C). However, storing lubricants near furnaces, steam lines or direct sunlight in high temperature climates for a prolonged time period may cause additives and base oils to oxidize prematurely. A significant darkening of the oil color is an indicator of this condition. In greases, the oil may begin to separate from the thickener; this is known as bleeding. The separated oil will typically appear on the surface of the grease, depending on the type of thickener used. In certain cases, when there has been oil/thickener separation, working the grease (mechanical agitation) can return the oil to the bulk lubricant. However, this is not recommended if the top grease surface has an accumulation of dirt. Lubricants that are potentially contaminated with volatile products, including diesel fuel, kerosene, or any other solvent, must never be stored in high temperatures. The presence of solvents can be identified by a test called the flash point test. In addition to evaporation and fire hazards, they can distort or even burst the storage vessel if tightly sealed.

Material of construction of storage tanks:

Storage tanks can be made from either stainless steel, mild steel plate, or anodized aluminum. Stainless steel and anodized aluminum have a relatively high material cost. In return, their maintenance costs are low. In certain cases, a thinner-gauge stainless steel may also be suitable to better contain the costs of construction. Mild steel plates are more commonly used for bulk storage tanks. The material cost is relatively low, but they require more expensive cleaning and corrosion-resistant treatments. Some mild steel tank designs and fabrication processes require shot or sand blasting plus performing one of the following depending on the type of product to be stored: lanolin-based rust preventative, oil-resistant paint, coating with plastic or epoxy resins or, aluminum spraying. Galvanized steels should not be used for tanks or piping due to risks associated with additive reactions in the formulated oil. Tank seams should be riveted or welded.

Methyl Ethyl Ketone:

Classified as Highly Flammable and Irritating to the eyes and respiratory system

Fire fighting measures:Extinguishing Media: Foam, Dry Powder, Co2. Water spray may not be effective for fire fighting but use to disperse vapours and protect fire fighters. Do not use water jets.Protective Equipment: Fire fighters should enter area wearing breathing apparatus and protective clothing.Special Consideration: Fire exposed containers should be sprayed with water to keep cool and avoid bursting.Products of Combustion: Carbon Dioxide, Water and possibly Carbon Monoxide.

Accidental release measuresDo not allow product to soak into drains, water courses, sewers or pits where the vapour may produce an explosive atmosphere. Soak liquid in absorbent material and collect

solids in a container. Wash down floor area as spillages can be slippery. Where spillage has occurred, personnel should wear suitable protective clothing and respirators where there is a risk of exposure to high vapour levels.

Storage Precautions:Store in accordance with the Highly Flammable Liquids and Liquefied Petroleum Gases Regulations.

Handling:Avoid inhaling vapour. Avoid contact with skin and eyes. Handle in a well ventilated area. All storage and transfer systems should be earthed to prevent build up of static discharge. Observe good standards of industrial hygiene.

Propane

Physical properties:

Molecular weight  : 44.096 g/mol

Liquid phaseLiquid density (1.013 bar at boiling point) : 580.88 kg/m3

Liquid/gas equivalent (1.013 bar and 15 °C (59 °F)) : 305.9 vol/volBoiling point (1.013 bar) : -42.11 °CLatent heat of vaporization (1.013 bar at boiling point) : 425.59 kJ/kgVapor pressure (at 21 °C or 70 °F) : 8.587 bar

Critical pointCritical temperature  : 96.74 °CCritical pressure  : 42.51 barCritical density  : 220.48 kg/m3

Gaseous phaseGas density (1.013 bar at boiling point) : 2.417 kg/m3

Gas density (1.013 bar and 15 °C (59 °F)) : 1.8988 kg/m3

Compressibility Factor (Z) (1.013 bar and 15 °C (59 °F)) : 0.98194Specific gravity  : 1.55Specific volume (1.013 bar and 25 °C (77 °F)) : 0.546 m3/kgHeat capacity at constant pressure (Cp) (1.013 bar and 25 °C (77 °F)) : 7.430001E-02 kJ/(mol.K)

Heat capacity at constant volume (Cv) (1.013 bar and 25 °C (77 °F)) : 0.0654 kJ/(mol.K)Ratio of specific heats (Gamma:Cp/Cv) (1.013 bar and 25 °C (77 °F)) : 1.1364Viscosity (1.013 bar and 0 °C (32 °F)) : 7.4692E-05 PoiseThermal conductivity (1.013 bar and 0 °C (32 °F)) : 15.65 mW/(m.K)

Since it is highly flammable propane must be stored in sealed containers and should be regularly checked for any leaks in the pipes or storage tanks.

Furfural as well is easily oxidised and is flammable so its leakage has to be prevented. Reduce or avoid exposure or contact with the chemical. It is advised to use earthed

equipment. Do not discharge the waste into the drain. It should be stored in a dark place stainless steel, steel aluminium or iron vessels can be used for storage. Should be kept away from heat sources and it stored for long periods, it should be stored in dark. Storage temperature : 20 degree Celsius.

Storage Tanks Mild steel, butt-welded tanks are suitable for normal storage conditions. Welding should be done with appropriate rods such as those containing .5% molybdenum. Annealing to prevent stress corrosion cracking is not required unless temperatures greater than 120°F (49°C) are expected. If iron pickup from mild steel tanks is a problem, the tanks may be lined with a suitable caustic soda-resistant coating. Vertical tanks are preferred over horizontal tanks since they take up less space and are easily supported on concrete slabs. Tank bottoms should be set in an asphalt grout for protection from exterior corrosion. All connections at the top of a tank should be grouped in one small area near the edge of the tank to permit servicing from a single location.Storage tanks should be heated and insulated if sustained ambient temperatures below 65°F (18°C) are expected. The thickness of the insulation will depend upon the energy costs of heating. The insulation must be wellprotected with jacketing to keep it dry.Heating can be accomplished with steam coils or electrical heating tape. For internal tank heating, a nickel bayonet-type heat exchanger is recommended.

The heater should be attached to a nickel flange, which can be fitted to a tank nozzle opening close to the bottom of the tank. The horizontal heater should be supported about eight inches (20cm) above the bottom of the tank and extend across the storage tank to about one foot (30cm) from the opposite side. As the caustic soda solution around the heater is warmed, a thermal agitation pattern will form in the tank, resulting in uniform heating of all caustic soda solution. A maximum of 15 psig (104 kPa) steam is recommended for heating the caustic soda solution.A temperature controller should be installed to maintain a caustic soda solution temperature of 85°–100°F (29°–38°C). The controller should include a high-temperature alarm and a thermocouple at the same liquid level as the steam coil. This guard against the thermocouple reading a false air temperature, causing the coils to overheat the remaining caustic solution when the tank is nearly empty. Another thermocouple located at eye level is convenient.Valves should never be installed in the vent line. It must be open to the atmosphere at all times.