Texaco gasification
Thread Content
Texaco gasification technology (overseas): The main structure of this gasifier is a single-nozzle bottom-fed slurry injection type; most of them use a water quenching process, but in IGCC power generation projects, the waste heat recovery process is also employed. The maximum capacity per furnace currently allows for a daily coal input of 2,000 tons. The operating pressures are mostly 4 MPa and 6.5 MPa; in a few projects, this pressure has reached 8.4 MPa as well. The first plant in our country to adopt this technology was Shandong Lunan Fertilizer Factory, which began operations in 1993; subsequently, several other plants adopted it as well, and currently there are about a dozen such plants. After nearly 30 years of application, Texaco’s gasification technology is undoubtedly a mature technology. It has been in use in our country for over a decade, and we enjoy significant advantages in terms of technical expertise and operational proficiency, as well as in the localization of equipment and the production of accompanying refractory materials. Its main advantage comes from coal water slurry, that is, it is easier to increase the pressure. If the pressure in the gasification furnace of Nanhua reaches 8.4 MPa, it becomes possible to synthesize methanol directly without compression, thereby saving energy used for compression. Chen Jiaren, a technical advisor at Shenhua Group’s Coal-to-Oil Company, pointed out that the main drawback of Texaco’s gasification technology is also related to coal water slurry; since coal water slurry contains 40% water, this reduces its calorific value. The requirements regarding coal quality have become stricter; coals with poor slurry-forming properties, high ash content, and high ash fusion points are less economical to use ； The gasification efficiency is relatively low, with a carbon conversion rate of about 95%. The specific oxygen consumption is the highest among various fluidized bed gasification processes, at around 400 standard cubic meters per thousand cubic meters (CO+H2) ； Hot furnace walls must be used; each batch of refractory bricks costs 500,000 dollars, while imported ones cost 1 million dollars, and their lifespan is less than 2 years. The nozzle, worth $150,000, has to be taken apart for repair after only about 2 months of use. Shell Gasification Technology (Abroad)
Reply to 1# huishengren: Hello, I would like to ask when the pressure in Nanhua’s gasification furnace reached 8.4 MPa? Which furnace?
Reply to 2# wpy-316: The pressure in the gasification furnaces for ammonia synthesis at Nanhua Company is currently around 8.4 MPa, and this is the case for both furnaces
Reply to 1# huishengren: Our plant has a shutdown interlock mechanism that activates when the burner pressure difference drops too low. However, this issue has occurred twice recently. After shutting down the plant for inspection, it was found that the wear on the burner and its coils wasn’t severe; we really can’t figure out what’s causing the problem After the burner pressure difference decreased, the following phenomena occurred: a drop in the pressure at the outlet of the slurry pump, a reduction in the burner pressure difference, and a rapid increase in the temperature of the thermocouple located at the top of the gasifier. In such situations, the measures taken included increasing the speed of the slurry pump; sometimes increasing its speed would restore the burner pressure difference, but other times it did not work. During the last shutdown, the speed of the slurry pump was increased significantly, and ultimately the supervisor ordered that the pump’s frequency be set to 100%, yet the burner pressure difference remained low and the pressure at the pump’s outlet stayed unchanged, even dropping further... The furnace temperature also decreased considerably. Finally, reduce the speed of the coal slurry pump. It tripped due to a very low burner pressure difference. Help analyze it
I wonder how long the vehicle can operate at 8.4 MPa? I guess it’s at most about 50 days. The higher the pressure in the water-coal slurry gasifier, the more severe the working conditions for the process burner, and thus its lifespan is shorter. Conversely, the lower the pressure in the gasifier, the more favorable the working conditions for the burner, and its lifespan is longer. I have an example from a manufacturer: the Texaco water-coal slurry gasifier, operating at 7.5 MPa, exceeded 100 days of continuous operation and reached 109 days.
Everyone, predict whether Texaco will become the mainstream player or Shell will
Reply to 6# xuyuan0206: It is likely that both types of furnaces will become mainstream in the future, but since the shell is more expensive, Texaco might have an advantage, after all its technology is more mature.
Welcome everyone to the Water-Coal Slurry Gasification Burner group. We communicate together and progress together. Group ID: 182443770
May I ask, what methods can be used to lower the ash fusion point of coal?
Adding a flux will do; it can effectively lower the ash melting point
I’ve learned it; is there a more detailed explanation?