Diesel fuel fire point

The oil for an oil-base mud can be diesel oil, kerosene, fuel oil, selected crude oil, or mineral oil. There are several requirements for the oil (1) API gravity = 36° - 37°. (2) flash point = 180°F or above, (3) fire point = 200°F or above, and (4) aniline point = 140°F or above. Emulsifiers are more important in oil-base mud than in water-base mud because contamination on the drilling rig is very likely, and it is very detrimental to oil mud. Thinners, on the other hand, are far more important in water-base mud than in oil-base mud oil is dielectric, so there are no interparticle electric forces to be nullified. 

OILS, DIESEL FUEL 4-D (68334-30-5, 68476-31-3) Forms explosive mixture with air (flash point 130°F/54°C). Oxidizers may cause fire and explosions. Violent reaction with strong oxidizers, fluorine. Incompatible with nitric acid, ammonia, ammonium nitrate. Flow or agitation of substance may generate electrostatic charges due to low conductivity. 

Four important tests which are used to characterize an engine fuel are the spontaneous ignition temperature (SIT), flash point, fire point, and smoke point. These tests are standardized, and specialized fuels have specific requirements as defined by these tests. The SIT is dependent on the composition of the fuel and the conditions of the walls of the cylinder. Diesel fuels require low SIT with short delay times of the order of 1-2 ms. The SIT of heptane (CN = 60) is 330°C, whereas benzene with CN = —10 has a SIT of 420°C. 

The flash point of a fuel is obtained by slowly increasing the temperature (5.6°C/min) of the liquid fuel in a standard container (flash cup) until sufficient vapor is given off to produce a flash as a flame is passed over the mouth of the cup every 30 s. The temperature of the oil at which this occurs is the flash point. This is an index of the volatility of the oil or liquid. It is used as an indication of the fire hazard of combustible liquids. For example, the Canadian specification for heating fuel oil stipulates a minimum flash point of 43°C, whereas the flash point of diesel fuel varies from 38°C to 52°C. The flash point and boiling point of various substances are compared in Table 4.4. 

Main fire pumps should be automatically controlled to start whenever there is a demand that reduces system pressure below a set point of say 7 barg. They should be large enough to keep the pressure above that set point at the most distant hydrant and at the system design flow rate. Spare pumps should be diesel engine driven with independent fuel tanks. Where steam is available, steam-driven pumps may be used to supplement the electric- and diesel-driven units. 

---