107results about How to "Renovation investment is small" patented technology

The invention relates to a natural circulating drum boiler with a smoke temperature rising system. The natural circulation drum boiler comprises a boiler body, a steam drum, a coal economizer, an SCR reactor, an air pre-heater and the smoke temperature rising system. A downcomer of the steam drum is connected with a low water drum of the boiler body. The temperature rising system is composed of a water pump, a switch valve and an electric adjusting valve. The low water drum of the boiler body is connected with an inlet pipe of the water pump through the switch valve, and an outlet pipe of the water pump is connected with a water feeding inlet pipe of the coal economizer in parallel through the electric adjusting valve. A check valve is connected between an outlet of the water pump and the electric adjusting valve. The smoke temperature rising system is applicable to subcritical and ultra-high pressure natural circulation drum boilers, the SCR reactor can be made to run normally under the conditions / condition of low loads and / or low atmosphere temperature, and therefore the smoke emission quality of the subcritical and ultrahigh pressure natural circulation drum boilers under the conditions / condition of the low loads and / or the low atmosphere temperature can reach national standards.

The invention discloses an ultra-low phosphorus steel smelting method. Dephosphorizing pretreatment is conducted firstly, and then operation is conducted through a double slag method. A dephosphorization period and a blowing period are included. According to the dephosphorization period, a dephosphorization agent and pre-slag left by a previous converter serve as slagging materials to be subjectedto dephosphorization smelting, and alkali converter slag is obtained; according to the blowing period, primary blowing is conducted, specifically, the oxygen flow rate during primary blowing is appropriately decreased, the converter bottom blowing strength is larger than or equal to 0.045 Nm<3> / (t.min), the oxygen-supplying blowing time is 6-7 min, after primary blowing is completed, converter slag is discharged, and then new slag is added to be slagged again; and the final converter slag alkalinity of secondary blowing is controlled to be 3.5-4.5, the content of FeO is 18-25%, the content ofMgO is 8-10%, the final temperature is 1600-1630 DEG C, the content of final C is 0.03-0.06%, a special slag-stopping plug is adopted before steel taping, after 3 / 4 steel taping is conducted, a slag-stopping awl is additionally arranged, and 40-60% of later-period slag which is generated after secondary blowing is finished is left to serve as a slagging material of later converter steel. Throughthe technology, the converter final P can be stably controlled to be 0.005% or below.