Producer gas generator

                                                  Producer gas generator

Gas producer is a production equipment that converts coal into combustible gas - gas (mainly composed of CO, H2, CH4, etc.). The working principle is as follows: after screening the coal that meets the gasification process index, it is added into the gas furnace by the coal feeder, and the mixed gas of self-produced steam and air is bubbled from the bottom of the furnace as the gasification agent. The coal in the furnace generates combustible gas through physical and chemical reaction (double stage furnace: the upper gas filters tar through cyclone degreaser and electric trap, and the lower gas removes dust through cyclone dust collector and is transported to users after mixing) for users' use. It is widely used in various furnace shapes within the required temperature range of various thermal furnaces, such as steel rolling furnace, annealing furnace, forging furnace, steel pipe furnace, glass furnace, aluminum melting furnace, copper furnace, ceramic furnace and so on.
working principle
The producer gas is generated by mixing water vapor and air to form gasification agent and then flowing through the hot fixed combustion bed. The oxygen and steam contained in the air react with the carbon in the fuel to produce producer gas containing Co, CO2, H2, CH4, N2 and other components. The steam mixed with air improves the thermal efficiency and reduces the temperature of the combustion bed, thus controlling the formation of frit. The reaction between steam and carbon is endothermic reaction: C + H2O = CO + h2-q (q is heat, the same below). When oxygen reacts with carbon, heat is released: 2C + O2 = 2CO + Q the temperature of combustion bed depends on the saturation temperature of gasifying agent, particle size and type of fuel and furnace type of generator. The temperature of combustion bed is very important, because for a given fuel and furnace type, it determines the composition of generator gas: a large amount of combustible gas can be produced at high temperature. Therefore, it is important to keep the combustion bed high temperature without forming frits. The temperature of forming frit depends on the slag melting characteristics of fuel. When oxygen is sufficient, there will be two reactions: 2CO + O2 = 2co2 + QC + O2 = CO2 + Q. Therefore, the production of CO does not necessarily mean that any carbon combustion can reduce the calorific value of gas. In addition, some water vapor also reacts with Co. when each volume of CO is converted into CO2, the same volume of H2 is generated at the same time: CO + H2O = CO2 + H2. Therefore, there will be no heat loss. In the reduction layer, when its temperature is lower than 1200 ℃, the following rapid reaction will occur: CO2 + C = 2coh2o + C = CO + H2. When the gas passes through the reduction zone, the content of combustible gas increases rapidly, while the content of CO2 and water vapor decreases. After passing through the reduction zone, some gas is extracted and flows through the bottom cyclone and forced air cooler. This gas is called "bottom gas", and its temperature is about 400 ℃. In the dry distillation layer, the fuel fed into the generator is dried, preheated and carbonized successively, and the generated steam, tar mist and gas leave the generator from the top. This part of gas is called "top gas", and its temperature is maintained at about 120 ℃.

Basic use
Many people will feel at a loss when they hear about the gas generator for the first time. What is its purpose? In fact, many customers who use the gas generator know that the gas of the gas generator is a kind of fuel gas obtained from coal gasification, but the main purpose of the gas generator is industrial fuel.
With the development of industry and the development of coal, natural gas and oil, the proportion of coal in the energy composition of various countries has gradually decreased, resulting in an energy crisis all over the world. The gas generator is also adapting to the market demand and updating from generation to generation. In China, coal is always the most important energy. A number of gas generating stations have been built all over the country, all walks of life and all industries. In the current society, in order to make full use of China's rich coal resources, under the condition that other new gasification methods are not popularized, gas generator gas is still an effective gasification method, especially for small and medium-sized enterprises with a wide range.
Specific purpose of gas generator gas:
Usage 1. Gas generator gas can be used for heating industrial kilns, such as forging heating furnace and heat treatment furnace in mechanical industry; Glass industry molten pool; Tunnel kiln for grinding wheel and refractory industry.
Usage 2. The gas from the gas generator can be used for smoke elimination and dust removal of various boilers. The smoke and dust are very serious in the production of various industrial boilers, especially small and medium-sized boilers. In addition to continuously improving the fuel mode and setting up various high-efficiency dust removal equipment, using the gas from the gas generator as fuel is one of the recognized good methods at home and abroad

Main classification
According to different gas making processes and the quality of produced gas, gas generators are divided into single-stage gas generators, double-stage gas generators and dry distillation gas generators.
Single segment
The product of single-stage gas producer belongs to a thermal processing process of solid fuel (coal or coke) through gas, that is, oxygen or oxygen compounds (steam and carbon dioxide) pass through the high-temperature solid fuel (coal and coke) layer, in which the organic substances (air and water steam) that play an oxidation role are called gasifying agents, and the mixed gas containing hydrogen, carbon and methane is called gas.
Furnace structure: full water jacket structure, with self-produced steam pressure of 294kpa, which can be directly connected to the gas furnace as gasification agent.
Coal feeding mechanism: it adopts mechanical coal feeding structure, with simple operation, convenient maintenance and good air tightness.
Ash cleaning mechanism: hydraulic transmission device is used for wet one-sided ash removal. The furnace has the advantages of uniform feeding, slag removal and air distribution, simple operation, convenient adjustment and reliable operation.
The atmospheric pressure fixed bed gas generator generally takes lump anthracite or bituminous coal and coke as raw materials and uses steam or the mixture of steam and air as gasification agent to produce gasified gas with carbon monoxide and hydrogen as the main combustible components. Zoning of fuel layer in gas furnace 1 - drying layer 2 - retort layer 3 - reduction layer 4 - oxidation layer 5 - ash layer.
Supporting equipment
Electric tar precipitator
The electric tar precipitator is used to filter the tar in the gas. The structure of the electric tar precipitator is concentric, tubular and honeycomb. No matter what kind of structure, its working principle is to apply high-voltage direct current between the metal wire and the metal pipe wall [or electrode plate], so as to maintain an electric field sufficient to ionize the gas and form a corona zone between the anode and cathode.
Cyclone dust collector
Cyclone dust collector is a kind of dust removal device. The mechanism of dust removal is to make the dusty air flow rotate, separate the dust particles from the air flow and trap them on the wall with the help of centrifugal force, and then make the dust particles fall into the ash hopper with the help of gravity. Cyclone dust collector was put into use in 1885 and has developed into various types. According to its flow entry mode, it can be divided into tangential entry type and axial entry type. Under the same pressure loss, the latter can treat about three times as much gas as the former, and the gas flow distribution is uniform. The ordinary cyclone dust collector is composed of a simple body, a cone, an air inlet and an exhaust pipe, etc. Cyclone dust collector has the advantages of simple structure, easy manufacture, installation, maintenance and management, low equipment investment and operation cost. It has been widely used to separate solid and liquid particles from gas flow or solid particles from liquid. Under normal operating conditions, the centrifugal force acting on particles is 5 ~ 2500 times that of gravity, so the efficiency of cyclone is significantly higher than that of gravity settling chamber. Mostly used to remove 0.3 μ Particles above M, parallel multi tube cyclone device pair 3 μ M particles also have a dust removal efficiency of 80 ~ 85%. The cyclone dust collector made of special metal or ceramic materials with high temperature resistance, abrasion resistance and clothing can be used at temperatures up to 1000 ℃ and pressures up to 500 ℃ × Operate at 105Pa. In terms of technology and economy, the pressure loss control range of cyclone dust collector is generally 500 ~ 2000Pa.
kiln
Steel rolling heating kiln
Steel rolling heating furnace is generally composed of seven parts: heating furnace body, cooling system, combustion system, material inlet and outlet, smoke exhaust system, waste heat recovery system and automatic control system. According to the discharging mode, it can be divided into side discharging and end discharging. It is mainly used for heating billet before rolling. The combustion atmosphere of steel rolling heating furnace is reducing atmosphere, which reduces the burning loss of billet and improves the heating quality of billet.
Bell type annealing kiln
The bell type annealing kiln is composed of two furnace platforms, two inner covers, a heating cover and a cooling cover. When one furnace platform is heating, heating and thermal insulation, the other furnace platform is in the process of cooling and unloading. The heating cover heats two furnace platforms alternately, which can save energy consumption and realize continuous production.
Tunnel kiln
Tunnel kilns can be divided into high temperature tunnel kilns and medium temperature tunnel kilns according to temperature. There are various structural forms of tunnel kiln. The lining can be in the form of heavy refractory brick or light refractory brick. The kiln top can be divided into arch roll structure or flat ceiling structure, and the shell can be metal steel plate structure or red brick outer wall structure. The specific forms can be designed and made according to the different conditions of products and users. Tunnel kiln is mainly used for firing refractories, ceramics and chemical powders. Tunnel kiln has large output and stable product quality.
All fiber trolley type heat treatment kiln
The all fiber trolley type heat treatment kiln is composed of furnace body, furnace door, trolley, furnace door lifting mechanism, trolley walking mechanism, gas generator, temperature control display and so on. The furnace body is welded by steel framework and steel plate, and the furnace lining is composed of fire-resistant limit block structure.
Trolley furnace is suitable for annealing, normalizing and tempering of large and large quantities of castings and forgings. Trolley type furnace has high heat utilization of fuel and little pollution to the surrounding environment.
raw material
Coal to gas is a technology that uses coal or coke and other carbonaceous substances as raw materials and air and steam as gasification agent to obtain combustible gas by gasification in the atmospheric pressure fixed bed gas generator. The main components of the generated gas are carbon monoxide, hydrogen, nitrogen and carbon dioxide, and the combustible components are carbon monoxide and hydrogen. Due to the large amount of inert component nitrogen, the calorific value of the gas is not high, and the low calorific value is about 6 MJ / nm.
There are two kinds of gas making technology of gas producer, cold gas and hot gas. Different fuel gases can be selected according to the nature of products. Hot gas can be used to heat products that do not require fuel cleanliness; Heating products requiring fuel cleanliness can purify the prepared gas into clean cold gas. The dust content and harmful components (such as H2S) of the cold gas are very low and will not pollute the products, so it can be fired with open flame. The traditional coal combustion is not easy to control the temperature of the kiln. It often happens that the temperature cannot rise or fall. The application of cold gas and hot gas to heat products, such as adjusting the kiln temperature, only need to adjust the opening of gas valve and air valve, which is very simple. It has a very obvious effect on improving product quality, product production process, working conditions and environmental sanitation.

technical parameter
Technical parameters of gas producer
name
Company
Generator specification
- - - - - - -
Furnace diameter
mm
one thousand and six hundred
one thousand and eight hundred
two thousand
two thousand and four hundred
two thousand and six hundred
three thousand
three thousand and two hundred
three thousand and four hundred
Furnace sectional area
m2
two
two point five four
three point one four
four point five two
five point three one
seven point zero seven
eight point zero four
nine point zero eight
Fuel layer height
mm
one thousand
one thousand
one thousand
one thousand
one thousand
one thousand
one thousand
one thousand
Height of fire layer
mm
100~300
- - - - - - -
Ash layer height
mm
100~300
- - - - - - -
Applicable fuel
Non cohesive bituminous coal, anthracite, coke
- - - - - - - -
Fuel particle size
mm
13~25 25~50
- - - - - - --
Fuel consumption
Kg/h
350~460
500~600
500~720
700~1040
850~1200
1700~2000
1800~2200
2500~2800
Gasification agent
Air, water vapor
- - - - - - - -
Gas production
Nm3/h
1200~1600
1500~2100
1750~2500
2500~3600
3000~4300
6000~7000
6500~7500
7000-9000
Ash tray speed
r/h
three point five
three point five
two point two three
two
one point seven
one point seven
one point seven
one point five
Calorific value of gas
KJ/Nm3
5020~5670
- - - - - - -
Gas outlet temperature
℃
400~550
- - - - - - -
Gas outlet pressure
Pa
980~1470
1470-1960
- - - - - -
Blast pressure
Pa
<4000
<6000
- - - - - -
Saturated air temperature
℃
50-65
- - - - - - -
Working pressure of water jacket
Pa
<100Kpa
<294Kpa
- - - - - -
Pressure of fire detection hole
Pa
<100Kpa
<294Kpa
- - - - - -
Furnace sheath drive motor power
KW
four
five point five
- - - - - -
Coal hopper lifting motor power
KW
one point five
three
- - - - - -
Total weight of equipment
T
twelve
fifteen
nineteen
twenty-four
twenty-eight
forty-two
forty-five
fifty-five
matters needing attention
Folding environmental protection standard
(1) Set up water sealed pool (recycling) to ensure that the water sealed sewage will not be discharged.
(2) Condensed phenol containing wastewater is collected and vaporized for reuse.
(3) For equipment with high noise, the way of building sound insulation shall be adopted to control noise pollution.
(4) Centralized recycling and comprehensive utilization of solid waste.
(5) Reasonably design the air supply process of the oven, and set the gas release igniter to ensure that the released flue gas meets the emission standard.
Folding safety measures
(1) Bell jar valve is set in the system. When the system is overpressured, it will automatically release and relieve the pressure. Multiple water seals are set in the system, which can automatically relieve the pressure in case of overpressure.
(2) Steam purging is set for all equipment in the system to prevent explosion and gas poisoning caused by mixing air and gas.
(3) The coal feeder of the gas generator adopts two-way and double drum coal feeding, and is equipped with plug-in plate valves up and down to effectively prevent gas leakage and purify the operation space.
Folding gas purification
The crude hot gas (temperature 500 ~ 600 ℃) generated by the gas generator first enters the double vertical pipe and is cooled and washed by the hot circulating water. Part of the dust in the gas is discharged from the water seal at the lower part of the double vertical pipe with the hot circulating water. The gas temperature after being washed and cooled by the double vertical pipe is about 80 ℃, and enters the washing tower for cooling, washing and dust removal. The gas temperature is cooled to 30 ~ 45 ℃, and the dust content at the outlet is generally less than 50mg / m3. After the isolation water seal, it enters the electrostatic precipitator for deoiling and dust removal. The total content of tar and dust in the gas is not more than 100mg / m. It is pressurized to 8-15kpa by the gas booster (which can also be adjusted according to the user). After the sulfur is removed by the desulfurization tower, it can be used by the user.
Folding steam regulation
Improper control of steam consumption often leads to large blocks and scabs in the gas generator, which seriously affects the quantity and quality of gas production. The existing varieties of raw materials for gas gasifier gasification are complex. Therefore, the difference and percentage of steam blowing up and down cannot be the same, which should be determined according to the performance of raw materials. It is mainly based on the ash melting point of raw materials, followed by the ash content of raw materials,
Therefore, for coal with different performance, how to use steam reasonably, only when the instrument is accurate, the valve is tight, the pressure of low-pressure steam main pipe is stable, and pay attention to the blowing queue, through practice and understanding, we can finally get a more appropriate steam consumption and up-down blowing percentage, which is beneficial to high yield and low consumption.