AU2020101514A4

AU2020101514A4 - Fire extinguishing compositions and preparation methods thereof

Info

Publication number: AU2020101514A4
Application number: AU2020101514A
Authority: AU
Inventors: Lei Cao; Lijun Chen; Chaobiao Huang; Rujiang Li; Xia LIN; Weichao Pan; Chao Wang; Yifei Wang; Yuan Zhu
Original assignee: Xingzhi College of Zhejiang Normal University
Current assignee: Xingzhi College of Zhejiang Normal University
Priority date: 2020-07-27
Filing date: 2020-07-27
Publication date: 2020-09-03
Anticipated expiration: 2028-07-27

Abstract

A method for preparing aerosol fire extinguishing agent is described as the following, first, grinding nitric acid, potassium, strontium nitrate, potassium citrate, sucrose and sodium bicarbonate and sieving through a 100-mesh sieve; and then fully mixing 39.0-40.0% of potassium nitrate, 26.5-27.5% of strontium nitrate, 14.5-15.0% of potassium citrate, 17.5% of sucrose and 1-1.5% of sodium bicarbonate, and then pouring the mixture into a special mold to prepare a molded fire extinguishing agent column; Then immersed in 45.5% phenolic resin alcohol solution for 10 seconds; Finally, the fire extinguishing agent column is put into an oven at 80 °C and dried for 24 hours to obtain the finished fire extinguishing agent. The fire extinguishing agent prepared by this method has fast fire extinguishing speed and good effect.

Description

AUSTRALIA

PATENTS ACT 1990

INNOVATION PATENT SPECIFICATION FOR THE INVENTIONENTITLED:

Fire extinguishing compositions and preparation methods thereof

The invention is described in the following statement:-

Fire extinguishing compositions and preparation methods thereof

TECHNICAL FIELD

The invention relates to the technical field of chemical fire extinguishing agents, in particular

to a preparation method of an aerosol fire extinguishing agent.

BACKGROUND

Aerosol refers to the solid or liquid as the dispersed phase, gas as the dispersion medium

formed by the sol. In general, this system is stable or quasi-stable, with a liquid or solid

component having a particle diameter of less than1Im. Aerosol fire extinguishing technology

is a new high-tech fire extinguishing technique developed on the basis of military pyrotechnic

technology, which was applied to large-scale oil tank fire extinguishing by Chinese scientists

in the 1960s. And made a major breakthrough, this is the first aerosol technology. In the

1980s, the former Soviet scientists and technicians successfully tested the aerosol fire

extinguishing technology that can extinguish fire in a full-submerged manner, and in recent

years, extinguishing fire with aerosol has become a potential fire extinguishing technique. It

is mainly used to put out the initial fire in the closed space such as library, archives,

transportation vehicle and machine room. this technology has opened up a new way for the

substitution research of Halon fire extinguishing technology.

In that fire extinguish mechanism of the aerosol fire extinguishing agent, solid or liquid

aerosol particle generated by combustion chemically and physically interact with active

groups in the flame, such as 0, H, OH, etc., For example, absorbing oxygen, isolating oxygen, absorbing heat, etc., to prevent the combustion reaction from continuing, so as to achieve the purpose of extinguishing the fire.

In the research and development of aerosol fire extinguishing agent coolant, relevant

institutions and personnel in China have done a lot of work and achieved some results. There

are two kinds of cooling methods: Physical cooling method and chemical cooling method,

among which the cooling effect of physical cooling is not ideal enough, and it is easy to cause

the tragedy of a second fire after a fire is put out.

SUMMARY

The purpose of the present invention is to overcome the disadvantages of the prior art and

provide a preparation method of an aerosol fire extinguishing agent which is simple in

preparation method and has good fire extinguishing effect.

In order to solve this technical problem, the adopted technical scheme is as follows:

A method for preparing an aerosol fire extinguishing agent comprises the following steps:

(1) Grind potassium nitrate, strontium nitrate, potassium citrate, sucrose and sodium

bicarbonate respectively and sieve them through 100 mesh;

(2) According to the mass ratio of potassium nitrate of 39.0 ~ 40.0%, strontium nitrate of

26.5 ~ 27.5%, potassium citrate of 14.5 ~ 15.0%, and sucrose of 1 7 .5 %, Sodium

bicarbonate 1 ~ 1.5% is mixed well to obtain fire extinguishing agent powder material;

(3) The mixed fire-extinguishing agent powder was poured into a special mold with a

diameter of 2.5 cm, and the pressure of the press was set to 2.5 MPa, the time of pressing

the mold was 8 min, to obtain a molded fire-extinguisher column;

(4) Immerse the shaped fire extinguishing agent column into the phenolic resin alcohol

solution with a mass fraction of 45.5% for 10 seconds;

(5) The fire extinguishing agent column is put into an oven at 80 °C for drying for 24 hours

to obtain the fire extinguishant finished product.

The finished product of the extinguishing agent is placed in a special extinguisher sleeve to

ignite the eruption in a suitable manner.

The fire extinguishing mechanism is as follows: The solid or liquid aerosol formed in the

process of fire eruption by the aerosol fire extinguishing agent with negative oxygen balance

ratio contains a large amount of incomplete oxidation products such as C, CH, CN, etc., that

is, the aerosol has strong reducibility. When in contact with a flame, it may chemically and

physically interact with active groups in the flame, such as 0, H, OH, etc., resulting in

reduced oxidizing power and reduced combustion; on the other hand, an aerosol forms a film

on the surface of gasoline, Isolate gasoline from contact with air to extinguish fire.

The resulting extinguishing agent has the following advantages:

(1) In that fire extinguish, the cooling effect is obvious, the fire extinguish speed is fast, the

effect is good, and the occurrence of the secondary fire is effectively restrained.

(2) The gas generated in the fire extinguishing process is non-toxic and harmless.

(3) The aerosol fire extinguisher made of the fire extinguishing agent is smaller in volume,

portable, low in price, convenient in operation and safe and reliable than the existing

common fire extinguishers.

(4) It can realize the reuse of the fire extinguisher shell.

DESCRIPTION OF THE INVENTION

The raw materials used in the following examples were all analytically pure. The features of

the invention are further described below by way of examples, but the invention is not limited

to the following examples.

Example 1

A method for preparing an aerosol fire extinguishing agent, Grind potassium nitrate,

strontium nitrate, potassium citrate, sucrose and sodium bicarbonate respectively and sieve

them through 100 mesh; Weigh the above components according to the mass fraction, and

take potassium nitrate of 39.5%, strontium nitrate of 27.0%, potassium citrate of 14.5%,

sucrose of 17.5%, and sodium bicarbonate of 1.5% for thorough mixing; Pour the well-mixed

fire extinguishing agent precursor into the special mould, set the pressure of the press to

2.5MPa, and set the press time to 8min, After molding, it was taken out and immersed in a

phenol-formaldehyde resin alcohol solution with a mass fraction of 45.5% for 10 seconds,

and the aerosol column coated with the curing agent was placed in an oven at 80 °C for

drying, and then taken out for 24 hours to obtain a finished fire extinguishing agent.

Example 2

A Preparation Method of Aerosol Fire Extinguishing Agent. The ingredients were weighed

according to the following mass fractions: Potassium nitrate 39.0%, strontium nitrate 27.5%, potassium citrate 15.0%, sucrose 17.5%, sodium bicarbonate 1.0%. The preparation method was the same as in Example 1

Example 3

A method for preparing an aerosol fire extinguishing agent, The ingredients were weighed

according to the following mass fractions: Potassium nitrate 40.0%, strontium nitrate 26.5%,

potassium citrate 14.5%, sucrose 17.5% and sodium bicarbonate 1.5%. The preparation method

was the same as in Example 1.

Application Example

In a metal container having a diameter of 56 cm and a height of 35 cm, 7.5 liters of water was

previously added, followed by 1 liter of No. 92 gasoline, which was ignited. Subsequently,

with the extinguisher to which the extinguishing agent obtained in Example 1 was added, the

fire was aimed at the flame and, after 12 to 15 seconds, the flame was completely extinguished

and did not reignite.

Claims

THE CLAIMS DEFINING THE INVENTION ARE AS FOLLOWS:

1. A method for preparing an aerosol fire extinguishing agent, characterized in that it

comprises the following steps:

grinding and passing through 100 mesh screen potassium nitrate, strontium nitrate,

potassium citrate, sucrose and sodium bicarbonate respectively;

mixing potassium nitrate 39.0 ~ 40.0%, strontium nitrate 26.5 ~ 27.5%, potassium citrate

14.5 ~ 15.0%, sucrose 17.5%, Sodium bicarbonate 1 ~ 1.5%;

pouring the evenly mixed fire extinguisher powder material into a mould with a diameter

of 2.5 cm, and set the pressure of the press to 0.5 MPa, leaving in the die time for 8 minutes;

immersing the fire extinguishing agent column in the phenolic resin alcohol solution with

the mass fraction of 45.5% for 10 seconds; and leaving the mixtures in the oven at 80 °C

for 24 hours.