초록 ▼

The invention described in the patent is an automatic control system which provides monitoring, supervision, and control of the process of filling of a tank or container with a liquid, where at the temperature of operation the vapor pressure of the liquid is at or above atmospheric pressure. The inv

The invention described in the patent is an automatic control system which provides monitoring, supervision, and control of the process of filling of a tank or container with a liquid, where at the temperature of operation the vapor pressure of the liquid is at or above atmospheric pressure. The invention provides an improved method of carrying out the process of filling of tanks with liquids such as ammonia, chlorine, propane, liquefied petroleum gas or any other liquid with high vapor pressure at the temperature of operation. The main advantage provided by the apparatus and method of the present invention is that an improved means is included for automatically stopping the filling process at the correct point, so as to avoid a possibly hazardous overfilled condition. One of the methods currently in use requires a mechanical valve which senses liquid level in the tank and is supposed to close so as to stop flow to the tank when the liquid has reached the maximum allowable level. The mechanical valve may malfunction and allow overfilling of the tank, and the fact that the valve is malfunctioning may not be readily apparent. The present invention does not require a mechanical valve of the type described above. Further there is a self-checking and self-monitoring capability so that users of the apparatus and method are warned of any malfunction.

대표청구항 ▼

A method for filling a tank with a saturated liquid, said tank having an inlet, and an outlet including a first flow restrictor, said first flow restrictor being mounted so as to be exposed to the gaseous phase associated with said saturated liquid until the liquid in said tank attains the pre-deter

A method for filling a tank with a saturated liquid, said tank having an inlet, and an outlet including a first flow restrictor, said first flow restrictor being mounted so as to be exposed to the gaseous phase associated with said saturated liquid until the liquid in said tank attains the pre-determined maximum allowable level, said method including the steps of: i) fluidly connecting said outlet with a lower pressure region through a vent line, said lower pressure region being created in a reduced-pressure reservoir connected to a pump or compressor reacting to the pressure in said reduced-pressure reservoir to pump fluid from said reduced-pressure reservoir when the pressure in said reduced-pressure reservoir exceeds a pre-determined maximum level, said vent line having a second flow restrictor therein downstream of said first flow restrictor, and said first and second flow restrictors being selected to yield, in said vent line, a fluid pressure below the pressure in said tank and above the pressure in said lower pressure region as long as said first flow restrictor is exposed to said gaseous phase; ii) introducing said saturated liquid into said tank through said inlet; and iii) ceasing said introduction of said saturated liquid into said tank when said fluid pressure changes indicating that said liquid has reached said pre-determined maximum allowable level in said tank and consequently has contacted said first flow restrictor.