How much do you know about commercial gas stoves?

Currently, the gas stoves used in Chinese restaurants and canteens in China mainly include stir-fry stoves, simmering stoves, large pot stoves, and steamers. These stoves use blower-type burners, which have low technology content, poor safety, and low thermal efficiency and functionality that cannot meet the needs of today's high fuel prices and the demands of chefs and restaurant owners. This is a major problem currently facing the stove industry.

In recent years, influenced by the national "energy conservation and emission reduction" policy, the commercial energy-saving stove market has been booming. However, due to the lack of standardized routes in the commercial energy-saving stove market and uneven R&D capabilities, the domestic energy-saving stove market remains in a state of chaos. As the industry continues to be regulated, the energy-saving stove industry must undergo a reshuffle. To stand out in the market, companies must possess strong professional knowledge, demonstrate real energy-saving effects, and master core energy-saving technologies.

Understanding of Traditional Commercial Gas Stoves:

Currently, commercial gas stoves on the market are mainly divided into three series: Cantonese stoves, Ningbo stoves, and Shandong stoves. However, the combustion method of each series still follows the traditional combustion method, which is "post-mixing combustion" (diffusion combustion in thermophysics). Post-mixing combustion means that combustion and mixing with oxygen occur simultaneously. The gas is ignited in the burner combustion chamber, and then the blower is turned on to supply oxygen to the ignited gas by blowing air. The low technology content results in unreasonable burner structures, low fuel burnout rates, energy waste, and environmental pollution in most stoves in use. This traditional stove combustion method has been used for many years. In the stove industry standards formulated by the national technical supervision department in 1999, the standard thermal efficiency is only 20%, resulting in a waste of 80%. The reasons for such low fuel utilization include thermal radiation, heat conduction, and air-fuel ratio issues.

Summary of Advantages and Disadvantages of Traditional Commercial Gas Stoves:

Advantages: High stability - Since the gas and air are not mixed before combustion, they are not affected by factors such as lateral pressure. The flame is more stable, and the flame size can be freely adjusted through the valve in front of the burner. Traditional commercial blower burners, consisting only of a blower and a burner head, have a simple structure, low price, and are widely used in the current domestic commercial stove industry.

Disadvantages: Shallow combustion chamber stoves are widely used, with a depth of 30mm and a total air intake of about 130mm. Large air intake holes reach 4-6mm, resulting in an abnormal gas-oxygen mixing ratio for combustion, causing incomplete combustion of the gas, producing a large amount of unburned high-carbon gases that are discharged from the flue, with high-temperature exhaust gas emissions, low thermal efficiency, and high gas consumption.

1. The distance between the bottom of the pot and the stove surface is 20mm, which is too long. Small flames cannot reach the bottom of the pot, resulting in waste.

2. The air intake holes are too large, and the air pressure and speed are too high. The fuel is blown to the flue around the stove and burns in the flue, resulting in waste.

3. Unreasonable air intake. When exceeding a certain load, the flame becomes red and yellow, the flame is large but weak, the flame is dispersed unevenly, black smoke is produced, combustion is poor, and pollution increases.

4. The depth is too shallow, the fuel stays in the combustion chamber for too short a time, premixing is insufficient, and most of the high-temperature zone of the combustion flame is above the combustion chamber. Coupled with strong wind, heat is blown to the flue, resulting in wasted heat, low fuel burnout rate, low utilization rate, and low thermal efficiency.

5. The gas cannot be reduced in pressure and speed.

6. The burner head is made of ordinary iron and uses ordinary manufacturing processes, resulting in a short service life and high maintenance costs.

7. At the same time, due to the long-term open flame (i.e., using high heat) of traditional stoves, there is high-temperature heat conduction and radiation, which causes a large amount of gas to be wasted.

Analysis of the Energy-Saving Principle of Energy-Saving Stoves:

As mentioned above, the thermal efficiency of traditional commercial gas stoves is only 20%, and 80% is wasted. The main reasons for gas waste are three: incomplete combustion, thermal radiation and conduction, and air burning.

1. Incomplete combustion: Due to the limitations of the technical structure of traditional commercial gas stoves, normal and complete combustion of gas cannot be supported, resulting in a large amount of incompletely burned high-carbon gas being discharged from the flue, causing approximately % of the fuel to not be completely burned, but carried away by the high-temperature gas.

2. Thermal radiation and conduction: Traditional gas stoves rely on flames to transfer heat to the bottom of the pot through convection. However, the contact between the flame and the bottom of the pot is only instantaneous, and a large amount of heat is not utilized and dissipates into space (thermal radiation). The furnace structure of traditional stoves (refractory bricks, refractory cement) causes most of the heat to be absorbed by the stove itself (heat conduction), resulting in a stove temperature generally between 40-50 ℃. Thermal radiation and conduction waste approximately % of fuel.

3. Air burning: Also known as idle burning in the industry. Due to the particularity of Chinese cooking processes, chefs cannot turn off the stove when washing vegetables or brushing pots (the open flame is used for a long time or a fire is kept). Even without working conditions, the stove continues to burn, resulting in higher kitchen temperatures and wasting approximately % of fuel.

To ensure efficient and economical burning in commercial stoves, the principle is to improve thermal efficiency and reduce combustion consumption. In other words, this is achieved by reducing the three heat losses mentioned above.

Market Status Analysis of Commercial Energy-Saving Stoves:

The following is a discussion of the current market situation of commercial gas energy-saving stoves, including technology and related products:

1. Incomplete gas combustion (problem) - Premixing technology (method) - Flamed premixed stove (product).

Overview: Gas and oxygen are mixed and then combusted, forming a properly proportioned combustible mixture that enters the combustion chamber for combustion; this allows for complete combustion of the gas, effectively increasing the heat flow rate. This energy-saving method generally has an energy-saving effect of around %.

(1) Flamed premixed burner head: Gas and air are mixed below the mixer and then output to the burner head for ignition.

(2) Flameless premixed burner head: This represents an immature direction in the current energy-saving stove market. It uses far-infrared technology, and the burner is indirectly heated. A ceramic plate is prepared, and after the gas stove is ignited, the gas stove heats the ceramic plate, and this ceramic plate transfers the heat to the bottom of the pot.