Cogeneration is an energy conservation and environmental protection project that China vigorously promotes. In recent years, many fertilizer companies in Shanxi Province have launched cogeneration projects. As of now, there are large-scale coal chemical companies such as Tianji, Fengxi, Tianze, Lanhua, and Zibao that have been supporting the construction of cogeneration units. The total installed capacity is about 130 MW. However, in an interview conducted by the reporter in early May, these companies reported that at present, none of their cogeneration units are allowed to operate on the Internet, and all of them are idle. The reason is that the power department has set up a number of checkpoints on the power grid for cogeneration.
Cogeneration: considerable energy savings
Cogeneration is a highly efficient energy production method that combines thermal energy and electric energy production. It is currently the most efficient technology that can realize energy conversion on a large scale. "If the power generated by 1 kilogram of coal, 1 kilogram of coal heating, and 2 kilograms of coal cogeneration, the combined thermoelectric efficiency of 12,000 kilowatts of thermal power units is higher than that of 600,000 kilowatts of supercritical power generators and 60% of efficiency coal-fired boilers. Some managers of chemical fertilizer companies mentioned this set of figures to reporters when talking about the benefits of cogeneration, and they all agreed that: "The combined heat and power generation circulating fluidized bed boiler burns the ammonia production process while producing steam. The generation of flammable and explosive gases such as blown air and bleed air eliminates potential safety hazards and reduces exhaust emissions, so that the company's safety and environmental pressure are greatly reduced. Therefore, combined heat and power can not only reduce costs and increase efficiency, but also reduce The company's safety and environmental protection pressures are no longer a concern for enterprises to limit power consumption during the peak summer months, which is very beneficial to the safety, stability, and long-term operation of chemical plants.
Li Sanwen, Minister of Industry Management Department of Shanxi Chemical Industry Management Office, told reporters that in accordance with the principle of "relying power on electricity by heat and electricity", a set of 180,000 tons/year of synthetic ammonia and 300,000 tons/year urea production equipment ( In the following, the 1830 device) is equipped with a 12 MW generator set as an example. Its total thermal efficiency is high, and its thermoelectric ratio is good. Tons of ammonia can save 150 kwh of electricity and save 10,000 tons of standard coal or more per year. For example, after the 12 MW pumping-condensation turbine generator set of Shanxi Orchid Kechuang Fertilizer Co., Ltd. is put into operation, the circulating fluidized bed boiler can be blended with a larger proportion of gas-fired slag to achieve both the benefits and the waste. Purpose, this alone can save more than 10 million yuan each year.
According to calculations, there are currently 15 sets of 1830 devices in Shanxi Province. If all of them have developed cogeneration, the annual energy saving will exceed 150,000 tons of standard coal, saving more than 150 million yuan in capital, and the energy saving benefit will be considerable.
Cogeneration: Applying for access to the network is blocked
Because of the obvious energy-saving advantages of cogeneration, many provinces and cities in China have long been supported by government policies and have played a significant role. Most of the fertilizer companies in Shandong and Zhejiang provinces have realized self-sufficiency in electricity generation from combined heat and power, and their ability to resist risks has been greatly enhanced. The energy consumption of synthetic ammonia in Shandong Province is 310 kg/t compared with the national average, which is due to the widespread use of energy-saving measures including heat and power generation by chemical fertilizer companies. Jiangsu, Henan, Inner Mongolia and other provinces also encourage local enterprises to develop cogeneration. According to statistics, the current domestic heat and power generation rate for large-scale fertilizer companies is nearly 50%. However, in Shanxi, the current CHP companies have encountered many difficulties in applying for the national grid, and they are in a bad situation.
Many companies report that the power sector in some places imposes restrictions on cogeneration for various reasons. The approval procedures for power grids for power plants outside the power system are relatively complex and have many restrictions. For example, the self-owned power generation equipment of Shanxi Tianyue Company has applied to the provincial and local power companies for grid connection several times after completion. All of them were rejected by the power sector for affecting the system safety, being unable to treat with the power plant and not being able to merge into the factory substation. network. TIANJIN ZHONGHUA GAOPING CHEMICAL CO., LTD. has submitted grid-connected applications to the provincial and local power companies from May 2005 to February 2007. However, the provincial power company requires that the unit must be built with a boosted substation and then merged into the Jincheng area. The public power grid cannot be used as a captive power plant; the Haobao Group is currently affected by the local cogeneration policy, and although many efforts have been made to ultimately obtain approval for cogeneration, the methanol project is not yet available, and the company is impatient with the immediate start of the methanol project; Shanxi Yangmei Feng Xi Fertilizer (Group) Co., Ltd. has also reported that the company applied for a 50 MW cogeneration project, but the power sector is not allowed to use it for urea and fertilizer production.
As the heat and power co-production are being squeezed out, the cogeneration plant is idle, resulting in the exhausted production of waste slag and exhaust gas can not be comprehensively utilized. The boiler equipment and large enterprises have suffered heavy losses. At the same time, this has also caused high levels of energy consumption and production costs in the Shanxi coal chemical industry.
Chemical industry industry: call for policy implementation
The Shanxi Chemical Industry Association, on behalf of the company, reported its appeal. On May 11th, Wang Jun, the governor of Shanxi Province, wrote that the “Report on Encouraging and Supporting the Development of Coal-fired Chemicals in Our Province to Co-produce Cogeneration†proposed that “The provincial government is invited to help coordinate the relevant issues. The department's co-generation projects for coal chemical companies that have already been established shall simplify the procedures for online examination and approval, arrange online operations as soon as possible, and issue relevant specific policies to encourage and support coal chemical companies in our province to develop cogeneration, save resources, and reduce energy consumption. Safe and stable production." This made many chemical companies see a glimmer of hope.
Some experts believe that the country's direction for encouraging the development of cogeneration is correct, and there is legal protection, and the operability of the policy is also very strong. However, it is necessary to ensure that the implementation of the cogeneration policy is implemented. The rapid development of the urea industry in Shandong in recent years is an important reason for the large scale of power generation of urea companies. Therefore, it is suggested that Shanxi learn from Shandong's practices, formulate relevant support policies, and take effective measures to actively support urea enterprises to develop cogeneration projects.