阅读说明：本技术 一种水泥预分解窑系统及制备水泥熟料的方法 (Cement predecomposition kiln system and method for preparing cement clinker ) 是由 何小龙 胡芝娟 彭学平 代中元 陈昌华 于 2019-08-12 设计创作，主要内容包括：一种水泥预分解窑系统及制备水泥熟料的方法。将CO-2自富集型预分解窑、离线型预分解窑、预热器窑集于同一系统,可根据需要将系统切换为CO-2自富集型预分解窑、离线型预分解窑或预热器窑。极大降低了烟气中CO-2捕集提纯的投资和运行成本,为水泥行业实现碳减排提供有效的解决方案。而且,系统无需对回转窑(7)和冷却机(10)进行重新设计,大大降低制造成本。当系统切换为预热器窑时,可满足一列旋风预热器在线检修的需要。另外,改善了现有技术中窑尾烟气CO-2浓度低、净化提纯成本高的问题。(A cement predecomposition kiln system and a method for preparing cement clinker. Introducing CO 2 The self-enrichment type pre-decomposition kiln, the separation line type pre-decomposition kiln and the pre-heater kiln are integrated in the same system, and the system can be switched into CO according to the requirement 2 Self-enriching type pre-decomposing kiln, parting line type pre-decomposing kiln or preheater kiln. Greatly reduces CO in the flue gas 2 The investment and the operation cost of purification are collected, and an effective solution is provided for realizing carbon emission reduction in the cement industry. Moreover, the system does not need to redesign the rotary kiln (7) and the cooler (10), thereby greatly reducing the manufacturing cost. When the system is switched to a preheater kiln, the on-line maintenance requirement of the cyclone preheater in a row can be met. In addition, the kiln tail flue gas CO in the prior art is improved 2 Low concentration and high purification cost.)

A cement predecomposition kiln system which is characterized in that,

the system comprises a first row of cyclone preheaters, a second row of cyclone preheaters, a decomposing furnace, a smoke chamber, a rotary kiln, a cooler and a heat exchanger;

an air inlet of the first row of cyclone preheaters is connected with the decomposing furnace, and a discharge port of the first row of cyclone preheaters is connected with the smoke chamber; the air inlet of the second row of cyclone preheaters is connected with the smoke chamber, the discharge hole of the second row of cyclone preheaters is divided into two paths, one path is connected with the decomposing furnace, and the other path is connected with the smoke chamber;

the smoke chamber is connected with the rotary kiln; the rotary kiln is connected with a cooler;

the cooler is provided with a tertiary air pipe, the tertiary air pipe is divided into two paths through a switching part, one path is that the tertiary air pipe is connected with a heat exchanger, and the heat exchanger is connected with the decomposing furnace through a pipeline; the other path is that the tertiary air pipe is directly connected with the decomposing furnace without a heat exchanger.

The cement precalciner system according to claim 1, wherein a distributing valve is arranged at the discharge port of the second row of cyclone preheater, one end of the distributing valve is connected with the decomposing furnace, and the other end of the distributing valve is connected with the smoke chamber.

The cement precalciner system according to claim 1 or 2, wherein the distributing valve distributes the raw meal passing through the outlet of the second row of cyclone preheater to the decomposing furnace, the smoke chamber; the feed divider adjusts the raw material amount entering the decomposing furnace and the smoke chamber from the discharge port of the second row of cyclone preheaters.

The cement precalciner system of claim 1, wherein the switching member is selected from a valve.

The cement precalciner system of claim 4, wherein the valve is selected from a gate valve or a butterfly valve.

The cement precalciner system of claim 4,

the valves comprise a first valve, a second valve and a third valve; the first valve and the third valve are arranged on the tertiary air pipe, and the second valve is arranged on a pipeline connecting the heat exchanger and the decomposing furnace;

the first valve is arranged on a tertiary air pipe connecting the cooler and the heat exchanger, and the second valve is arranged on a pipeline connecting the heat exchanger and the decomposing furnace; the third valve is arranged on a tertiary air pipe which connects the cooler and the decomposing furnace.

The cement precalciner system of claim 1, wherein the number of stages of the first and second rows of cyclone preheaters is selected from 3-7 stages.

The cement precalciner system of claim 1, wherein the heat exchanger is provided with more than one gas inlet, more than one gas outlet;

one of the gas outlets is connected with a waste heat utilization or treatment system; the waste heat utilization or treatment system comprises a waste heat boiler for generating electricity and drying materials;

the cooler is selected from one of a grate cooler, a single-cylinder cooler and a multi-cylinder cooler.

A method of preparing cement clinker using the cement precalciner system of any of claims 1 to 8, wherein the method comprises:

adding the raw materials into a first row of cyclone preheaters and a second row of cyclone preheaters respectively, and exchanging heat between the raw materials and the flue gas in the cyclone preheaters;

the raw materials preheated by the first row of cyclone preheaters enter the decomposing furnace through one point or multiple points, the raw materials preheated by the second row of cyclone preheaters can be divided into two paths, wherein one path enters the decomposing furnace through one point or multiple points, and the other path enters the rotary kiln through the smoke chamber;

the hot raw materials decomposed in the decomposing furnace leave the decomposing furnace and enter a last-stage cyclone separator of a first row of cyclone preheaters, the hot raw materials enter a rotary kiln through a smoke chamber after gas-solid separation, the raw materials are calcined in the rotary kiln to form clinker, the clinker enters a cooler from an outlet of the rotary kiln and is cooled by the cooler, and cement clinker is obtained;

kiln gas formed in the rotary kiln is subjected to gas-solid heat exchange by the second row of cyclone preheaters and then is discharged from the outlet of the uppermost stage of cyclone separator; the flue gas formed in the decomposing furnace is subjected to gas-solid heat exchange by the first row of cyclone preheaters and then is discharged from the outlet of the uppermost stage of cyclone separator;

the tertiary air is divided into two paths by the switching component, and any one of the following paths is selected by adjusting the switching component: one path is that the tertiary air enters a heat exchanger through a tertiary air pipe, the tertiary air and the mixed gas of oxygen and circulating flue gas or the oxygen carry out heat exchange through the heat exchanger, the mixed gas of the circulating flue gas and the oxygen or the oxygen which are subjected to the heat exchange enter a decomposing furnace, the tertiary air which is subjected to the heat exchange enters a waste heat utilization or treatment system, the other path is that the tertiary air directly enters the decomposing furnace through the tertiary air pipe without passing through the heat exchanger, and the hot air in the tertiary air pipe enters the decomposing furnace.

The method for manufacturing cement clinker according to claim 9, wherein the raw meal is fed through an air inlet duct of the uppermost stage cyclone of the first and second series of cyclone preheaters or an air inlet duct of the uppermost stage cyclone of the first and second series of cyclone preheaters.

The method for preparing cement clinker according to claim 9, wherein when the switching member is switched to the tertiary air duct to connect the heat exchanger, the heat exchanger is connected to the decomposing furnace through a pipeline, the mixed gas of the circulating flue gas and the oxygen or the oxygen is subjected to heat exchange with the hot air in the tertiary air duct through the heat exchanger, the tertiary air after the heat exchange enters the waste heat utilization or treatment system, the mixed gas of the circulating flue gas and the oxygen or the oxygen after the heat exchange enters the decomposing furnace, and the decomposing furnace is oxygen-enriched combustion or total oxygen combustion.

The method for preparing cement clinker according to claim 9, wherein the third valve is closed and the first valve and the second valve are opened, the third air passes through the heat exchanger to heat the mixed gas or oxygen of the circulating flue gas and oxygen, the mixed gas or oxygen of the circulating flue gas and oxygen enters the decomposing furnace, and the decomposing furnace is oxygen-enriched combustion or total oxygen combustion, and the system is CO₂A self-enrichment type pre-decomposition kiln;

when the third valve is opened and the first valve and the second valve are closed, the tertiary air pipe is directly connected with the decomposing furnace, hot air in the tertiary air pipe enters the decomposing furnace, and the system is an offline pre-decomposing kiln;

when the first valve, the second valve and the third valve are all closed, the first row of cyclone preheaters do not feed raw materials any more, the fuel in the decomposing furnace is not supplied any more, when the material distributing valve distributes all the hot raw materials preheated in the second row of cyclone preheaters into the smoke chamber, the hot raw materials enter the rotary kiln and are calcined in the rotary kiln to form clinker, the clinker enters a cooler from the outlet of the rotary kiln and is then cooled by the cooler to obtain cement clinker, and at the moment, the system is a preheater kiln.

The method for manufacturing cement clinker according to claim 12, wherein when the third valve is closed and the first valve and the second valve are opened, the tertiary air passes through the heat exchanger to heat oxygen to enter the decomposing furnace, and the decomposing furnace is in oxy-fuel combustion;

when the third valve is closed and the first valve and the second valve are opened, the tertiary air heats the mixed gas of the circulating flue gas and the oxygen through the heat exchanger and enters the decomposing furnace, and the oxygen-enriched combustion is performed in the decomposing furnace.

Method for manufacturing cement clinker according to any of claims 9 to 13The method is characterized in that according to the gas flow direction, air is cooled to the high-temperature clinker by a cooler, and the air after heat exchange is divided into the following three paths: the first path of high-temperature air is used as secondary air and directly enters the rotary kiln for fuel combustion; when the third valve is fully closed and the first valve and the second valve are fully opened, the system is used as CO₂When the self-enrichment type pre-decomposition kiln is used, the second path of high-temperature air is used as tertiary air to preheat the mixed gas of the circulating flue gas and the oxygen or the oxygen through a heat exchanger, the preheated tertiary air enters a waste heat utilization or treatment system, and the preheated mixed gas of the circulating flue gas and the oxygen or the oxygen enters a decomposition furnace; when the third valve is fully opened and the first valve and the second valve are fully closed, namely the system is used as an offline pre-decomposition kiln, the second path of high-temperature air is used as tertiary air to directly enter the decomposition furnace for fuel combustion, and oxygen or mixed gas of the oxygen and circulating flue gas is not supplied into the decomposition furnace; and the third path of air enters a waste heat utilization or treatment system.

The method for manufacturing cement clinker according to claim 14, wherein the air outlet of the cooler is a first path, a second path, and a third path; or the first path of air is independently exhausted, and the second path and the third path of air are combined to exhaust air.

The method for preparing cement clinker according to claim 15, wherein the second and third paths combine to vent air, and the second and third paths share a vent pipe;

when the first valve, the second valve and the third valve are all closed, the first row of cyclone preheaters do not feed raw materials, the fuel in the decomposing furnace is not supplied any more, and when the material distributing valve distributes all the hot raw materials preheated in the second row of cyclone preheaters into the smoke chamber, namely when the system is used as a preheater kiln, the first path independently exhausts air, and the second path and the third path are combined to exhaust air.