Hash point

The heat transfer section of a plant was filled with oil after maintenance by opening a vent at the highest point and pumping oil into the system until it overflowed out of the vent. The overflow should have been collected in a bucket, but sometimes a bucket was not used, or the bucket was overfilled. Nobody worried about small spillages because the Hash point of the oil was above ambient temperature and its boiling point and auto-ignition temperature were both above 300°C. 

Other important properties include Hash point, volatility, viscosity, specific gravity, cloud point, pour point, and smoke point. Most of these properties are related directly to the boiling range of the kerosene and are not independently variable. The flash point, an index of fire hazard, measures the readiness of a fuel to ignite when exposed to a flame. It is usually mandated by law or government regulation to be 120° or 130° F (48° or 72° C), Volatility, as measured... 

Lenoir, J. M., Predict Hash Points Accurately, Hydrocarbon Processing J n., 95 (1975). 

Figure 2.1 Classification of an area hazardous due to combustible gases/liquids into zones 0, 1 and 2 [50], The value R is tabulated in Table 2.4 as a function of the filling rate into the tank (liquid with a Hash point <35°C). Dimensions given in metres.

Hash point measurements from the closed-cup method are quoted unless only data from the open-cup (oc) method are available. Data from Stephenson, R. M., Flash Points of Organic and Organometallic Compounds (New York Elsevier, 1987) Bond, J., Sources of Ignition (Oxford Butterworth, 1991). 

Kerosene is a refined petroleum distillate that has a hash point about 25°C (77°F) and is suitable for use as an illuminant when burned in a wide lamp. The term kerosene is also too often incorrectly applied to various fuel oils, but a fuel oil is actually any liquid or liquid petroleum product that produces heat when burned in a suitable container or that produces power when burned in an engine. 

The Hash point is a guide to the fire hazard associated with the use of kerosene it can be determined by several test methods, and the results are not always strictly comparable. Generally, the Hash point of kerosene is specified as being in excess of 38°C (100°F) because of production as well as safety considerations. 

The minimum hash point is usually dehned by the Abel method (IP 170), although the Pensky-Martens method (ASTM D-93, IP 34) may also be specihed. The TAG method (ASTM D-56) is used for both the minimum and maximum limits, whereas certain military specihcations also give minimum limits by the Pensky-Martens method (ASTM D-93, IP 34). The Abel method (IP 170) can give results up to 2-3°C (3-5°F) lower than the TAG method (ASTM D-56). 

In practice, hash point is important primarily for fuel handling. A hash point that is too low will cause fuel to be a hre hazard, subject to hashing... 

The most common solvents used in the preparation of Grignard reagents are ethers, typically diethyl ether or tetrahydrofuran (THI-). Ethereal solvents offer the advantage of stabilizing the Grignard reagent. The stabilization of phenylmag-iiesiuni bromide by two diethyl ether molecules was proven by the crystallization of the complex ] 12[. Due to the low Hash point of diethyl ether. 1 Ub is frequently the solvent of choice oil an industrial scale... 

ACETATO de p-fer-AMILFENILO (Spanish) (80-46-6) Combustible solid (Hash point 233°F/112°C). Reacts with strong oxidizers. Flow or agitation of substance may generate electrostatic charges due to low conductivity. 

AGENAP (1338-24-5) Combustible liquid (Hash point 300°F/I49°C oc). Incompatible with sulfuric acid, caustics, ammonia, aliphatic amines, alkanolamines, isocyanates, alkylene oxides, epichlorohydrin, strong oxidizers. Generally corrosive to metals. 

AGENT 504 (112-30-1) Combustible liquid (Hash point 180°F/82°C oc). Reacts, possibly violently, with oxidizers, acetaldehyde, alkalineearth. alkali metals, strong acids, ammonium persulfate, strong caustics, aliphatic amines, benzoyl peroxide, boranes, bromine dioxide, chromic acid, chromium trioxide, dialkylzincs. dichlorine oxide, ethylene oxide, hypochlor-ous acid, isocyanates, isopropyl chlorocarbonate. lithium tetrahydroaluminate, nitric acid, nitrogen dioxide, pentafluoroguanidine. perchlorates, peroxides, permanganates, phosphorus pentasulfide, sulfuric acid, tangerine oil. triethylaluminum, triisobutylaluminum. 

A,A -BlS(2-AMlNOETHYL)-l,2-DIAMINOETHANE (112-24-3) Combustible liquid (Hash point 275°F/I35°C). Aqueous solution is a strong organic base (pH 10 in 1% aqueous... 

BROMOPENTANE (107-81-3) Forms explosive mixture with air (Hash point 90°F/32°C). Violent reaction with strong oxidizers. Incompatible with strong acids. 

OCTACHLORONAPHTHALENE (2234-13-1) Combustible solid (Hash point unknown). Violent reaction with strong oxidizers, strong acids, powdered aluminum, potassium, sodium. 

Combustible liquid Hash point (open cup) 48°C (118°F) vapor pressure 3.2 torr at 20°C (68°F) autoignition temperature 293°C (559°F) vapor forms explosive mixtures with air within the range 1.5-9.9% by volume in air. n-Butyl acrylate may polymerize at elevated temperature. The reaction is exothermic and may cause pressure buildup and violent rupture of closed containers. The polymerization may be prevented by 40-60 ppm of hydroquinone or its monomethyl ether. Its reactions with strong oxidizers can be vigorous to violent. 

All binders formed from ethyl silicate have a relatively low flash point due to the ethanol released during hydrolysis (flash point of ethanol 12 C). The paint may have a somewhat higher flash point (15 C) because its ethanol content is low. The use of higher alkyl groups yields systems with higher Hash points. 

Binders with a fairly high flash point require a suitable solvent (e.g., propanol, butanol) and a silicate base that cannot release any alcohols of low Hash point during partial hydrolysis (e.g., tetrapropyl or tetrabutyl silicate). The slower evaporation of such alcohols delays the initial hardening of these paints. 

Class B Hash point < 21 C in the case of liquids that are miscible in all proportions with water... 

Ttw commeiclal product with 22% water has a hash point of 129°C. Explosive limits not given In the literature. 

The smoke, fire, and Hash points of a fatty material are measures of its thermal stability when heated in contact with air. The smoke point is the temperature at which smoking is first detected in a laboratory apparatus protected from drafts. The flash point is the temperature at which the volatile products are evolved at a rate sufficient to be ignited, but not to support combustion. The fire point is the temperature at which the volatile products support continued combustion. 

Hot oil heat exchange systems Since most hot oil (heat exchange) fluids will burn and are frequently used above their Hash points or boiling points, they represent an additional hazard in any process unit that uses them. A penalty factor between 0.25 and 1.15 is applied depending on quantity and temperature. 

Generally if the location uses chemicals in any of these four groups which have flash points less than 37.8"C or 100 "F and otherwise meets the specifications of a class I, division 1 location, special electrical equipment would normally be required. Special electrical equipment would normally be required for class II flammables (Hash points equal to or above 37.8 C or 100"F, but less than 60"C or 140 F) only if the materials are stored or handled above the flash points, while for class lllA flammables (flash points equal to or above 60 C or 140 F, but less than 93.3 C or 200 F), special electrical equipment is needed only if there are spaces in which the temperature of the vapors may be above the flash points. 

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