Method for establishing a coke sulfur fraction prediction model for use with high sulfur coal

Abstract

This invention discloses a method for establishing a coke sulfur content prediction model using high-sulfur coal. In this method, high-sulfur coal refers to a single type of coal with a sulfur content of 1.3–3.0%, which can be at least one of gas coal, gas-fat coal, fat coal, 1 / 3 coking coal, coking coal, or lean coal. The method includes steps for establishing coke sulfur content prediction models for different single types of coal and steps for establishing a coke sulfur content prediction model using high-sulfur coal. By predicting the sulfur content of coke obtained from different single types of coal and the contribution of different single types of coal to the sulfur content of coke obtained from blended coal based on the sulfur and volatile matter content of the single type of coal, a coke sulfur content prediction model using high-sulfur coal is finally obtained. This model effectively corrects the prediction deviation of coke sulfur content after the use of high-sulfur coal, keeping the prediction deviation within 0.1%, which is beneficial to blast furnace production operations and better achieves the goal of plants using more high-sulfur coal and reducing coal blending costs.

Description

Technical Field

[0001] This invention belongs to the field of coal blending and coking technology, specifically involving a method for establishing a predictive model for the sulfur content of coke blended with high-sulfur coal. Background Technology

[0002] In the past two years, with the rise in coking coal market prices, the coal blending costs of steel enterprises have continued to climb, resulting in significant cost pressure. To alleviate this pressure, it is necessary to optimize and adjust the coking coal resource structure. While ensuring the stable operation of blast furnaces, this involves reducing the proportion of high-priced, high-quality coking coal and increasing the use of low-priced, low-quality coal. However, without changing the coking process, the proportion of low-priced, low-quality coal can only be limited, and currently, the blast furnace volume of large steel enterprises is generally around 3000 m³. 3 The above places higher demands on coke quality. Therefore, there is limited room for cost reduction by simply decreasing the proportion of high-quality, strongly caking coal and increasing the proportion of low-priced, low-quality coking coal. Furthermore, low-ash, low-sulfur, strongly caking coking coal resources are extremely scarce, while high-sulfur, strongly caking coking coal is cheaper and relatively more abundant. Among coke quality indicators, coke strength has a far greater impact on blast furnaces than coke sulfur content. Therefore, to reduce blending costs and stabilize coke quality, steel companies often blend some low-priced, high-sulfur, strongly caking coking coal and reduce the use of high-priced, low-sulfur, strongly caking coal. Under the condition of stable coke strength, appropriately optimizing coke sulfur content can reduce blending costs.

[0003] However, the sulfur conversion of high-sulfur coking coal and low-sulfur coking coal differs significantly. Using the previous method of predicting coke sulfur content, it was found that the predicted values ​​had large deviations, which is detrimental to blast furnace production. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a method for establishing a coke sulfur content prediction model using high-sulfur coal. This method can reasonably use high-sulfur coal with a sulfur content of 1.3 to 3.0% and accurately predict the sulfur content of coke. This is beneficial for steel enterprises to reduce coal blending costs, save low-sulfur high-quality coking coal, stabilize the cold and heat intensity of coke, and ensure stable blast furnace production and smooth operation.

[0005] To solve the above-mentioned technical problems, the specific technical solution provided by the present invention includes the following steps:

[0006] 1. Prediction of coking sulfur content in different types of coal:

[0007] The six main types of coal commonly used for coking are: gas coal, gas-rich coal, coking coal, 1 / 3 coking coal, coking coal, and lean coal.

[0008] Let the total focal length be: K = (100 - V) d煤 ) / (100-V d焦 )×100; where V d煤 =V daf煤 ×(100-A d煤) / 100; the V d煤 Volatile matter on a dry basis, expressed as %; V d焦 The volatile matter content of coke is expressed on a dry basis, in %; V daf煤 The dry ash-free volatile matter of coal, expressed in %; A d煤 Ash content of coal on a dry basis, expressed as a percentage.

[0009] For any single type of coal i among the six major coking coal types, its total coke yield is denoted as Ki, which is: Ki = (100 - V) / ( ... di煤 ) / (100-V di焦 )×100, V di煤 =V dafi煤 ×(100-A d煤 ) / 100; where V di煤 V is the dry basis volatile matter of a single type of coal i. dafi煤 V is the dry ash-free volatile matter of a single type of coal i. di焦 The dry basis volatile matter of coke prepared from a single type of coal i.

[0010] For any single coal type i among the six major coking coal types, the coking sulfur content is predicted in segments according to the different sulfur and volatile matter content, based on the following model:

[0011] (1) For a single type of coal i, V daf ≥28%, or V daf <28% and S t,d煤 ≤1.3% of a single type of coal m, let S t,d焦1 =(-1.801×V) dm煤 +112.4)×S t,dm煤 / Km;

[0012] (2) For a single type of coal i, V daf <28% and S t,d煤 >1.3% of a single type of coal n, let S t,d焦2 = (-2.1052×V) dn煤 +110.03)×S t,dn煤 / Kn.

[0013] Where S t,d焦1 S represents the sulfur content in coke obtained from any single type of coal (m), expressed in %; t,dm煤 S represents the sulfur content in any single type of coal (m), expressed as a percentage (%). t,d焦2 S represents the sulfur content in coke obtained from any single type of coal (n), expressed in %; t,dn煤 The sulfur content in any single type of coal n, expressed as a percentage.

[0014] Clearly, the sets {m} of m, {n} of n, and {i} of i satisfy the following relations: {m}≤{i}, {n}≤{i}, {m}+{n}={i}; the sets {Km} of Km, {Kn} of Kn, and {Ki} of Ki satisfy the following relations: {Km}≤{Ki}, {Kn}≤{Ki}, {Km}+{Kn}={Ki}.

[0015] 2. Prediction of coke sulfur content in blended coal from different single types of coal

[0016] Let Xi be the proportion of any single coal i in the blended coal, and let Ki be the total coke yield. di煤 ) / (100-V di焦 )×100.

[0017] The coking rate of all single coal types i after forming blended coal is: ∑XiKi (i.e., ∑(Xi×Ki)).

[0018] The proportion of any single coal type i in the coking coal composition is: XiKi / ∑(XiKi).

[0019] In blended coal:

[0020] 1) For V daf ≥28% or V daf <28%, S t,d煤 For a single type of coal m with a sulfur content ≤1.3%, the total contribution of all such single types of coal m to the sulfur content of coke is denoted as S. t,d焦a :

[0021] S t,d焦a =∑[S t,d焦1 ×Xm×Km / (∑XiKi)]

[0022] =∑[((-1.801×V dm煤 +112.4)×S t,dm煤 / Km)×Xm×Km / ∑(Xi×Ki)]

[0023] =∑[(-1.801×V dm煤 +112.4)×S t,dm煤 ×Xm / ∑(Xi×Ki)].

[0024] 2) For V daf <28%, S t,d煤 For single-type coal with a sulfur content >1.3%, the total contribution of all such single-type coals n to the sulfur content of coke is denoted as S. t,d焦b :

[0025] S t,d焦b =∑[S t,d焦2 ×Xn×Kn / ∑(XiKi)]

[0026] =∑[(-2.1052×V dn煤 +110.03)×S t,dn煤 / Kn×Xn×Kn / ∑(XiKi)]

[0027] =∑[(-2.1052×V dn煤 +110.03)×S t,dn煤 ×Xn / ∑(XiKi)].

[0028] Clearly, the sets {Xm} of Xm, {Xn} of Xn, and {Xi} of Xi satisfy the following relationships: {Xm}≤{Xi}, {Xn}≤{Xi}, and {Xm}+{Xn}={Xi}.

[0029] 3) Sulfur content (S) in coke obtained from blended coal t,d焦总 for:

[0030] S t,d焦总 =S t,d焦a+ S t,d焦b .

[0031] Preferably, the high-sulfur coal refers to a single type of coal with a sulfur content of 2.0 to 3.0%.

[0032] After long-term research on the sulfur conversion rate of coking coals with different volatile matter and sulfur content, the inventors of this invention discovered that the conversion rate of high-sulfur coal with medium-low volatile matter content differs from that of other coking coals. By performing segmented predictions based on the different volatile matter and sulfur contents of coking coal, the accuracy of coke sulfur content prediction is high. The coke sulfur content prediction model established using the method of this invention, which incorporates high-sulfur coal, will... daf ≥28% or V daf <28%, S t,d煤 Coal with sulfur content ≤1.3% has coke sulfur content and V daf <28%, S t,d煤 The method of predicting the sulfur content of coke from coal types with a sulfur content >1.3% in stages effectively corrects the prediction deviation of coke sulfur content after blending with high-sulfur coal, keeping the prediction deviation within 0.1%. This is beneficial to blast furnace production operations and better achieves the goal of plants using more high-sulfur coal and reducing coal blending costs. In existing technologies, the predicted sulfur content of coke obtained from blending with ultra-high-sulfur single coals (2.0-3.0% sulfur content) is particularly distorted. However, the method of this invention, when predicting the sulfur content of coke obtained from blending with such high-sulfur single coals, still keeps the prediction deviation within 0.1%. This effectively solves the technical problem of steady-state production in blast furnaces with specific high-sulfur content coals, providing an important way for steel enterprises to develop high-sulfur coking coal resources and seek high-quality, low-cost coking processes. This is of great significance for the sustainable development and enhanced competitiveness of enterprises. Detailed Implementation

[0033] The present invention will be further illustrated below through specific embodiments. It should be noted that the following embodiments are only intended to illustrate the technical solutions and effects of the present invention, and are not intended to limit the scope of protection of the present invention.

[0034] 1. Prediction of coking sulfur content in different types of coal:

[0035] Commonly used coal types include: gas coal, gas-rich coal, coking coal, 1 / 3 coking coal, coking coal, and lean coal. To reduce costs, high-sulfur coking coal, high-sulfur coking coal, and high-sulfur lean coal can be used in combination.

[0036] Let the total focal length be: K = (100 - V) d煤 ) / (100-V d焦 )×100; where, V d煤 =V daf煤 ×(100-A d煤 ) / 100.

[0037] For any single type of coal i among the six major coking coal types, its total coke yield is denoted as Ki, which is: Ki = (100 - V) / ( ... di煤 ) / (100-V di焦 )×100, V di煤 =V dafi煤 ×(100-A d煤 ) / 100; where V di煤 V is the dry basis volatile matter of a single type of coal i. dafi煤 V is the dry ash-free volatile matter of a single type of coal i. di焦 The dry basis volatile matter of coke prepared from a single type of coal i.

[0038] The coking sulfur content of any single coal type i among the six major coking coal types is predicted, and the predictions are made according to different segments of sulfur content and volatile matter as follows:

[0039] (1)V daf ≥28%: S t,di焦1 =(-1.801×V) di煤 +112.4)×S t,di煤 / Ki.

[0040] (2)V daf <28%, S t,d煤 ≤1.3%: S t,di焦1 =(-1.801×V) di煤 +112.4)×S t,di煤 / Ki.

[0041] (3)V daf <28%, S t,d煤 >1.3%: S t,di焦2= (-2.1052×V) di煤 +110.03)×S t,di煤 / Ki.

[0042] 2. Prediction of coke sulfur content in blended coal from different single types of coal

[0043] Let Xi be the proportion of any single coal i in the blended coal, and its total coke yield Ki = (100 - V) / ( ... di煤 ) / (100-V di焦 )×100. Then the coking rate after blending all coal types is: ∑XiKi. The proportion of different coal types contributing to the total coking of the blended coal is: XiKi / ∑(XiKi).

[0044] 1) For a single type of coal i, V daf ≥28% or V daf <28%, S t,d煤 For a single type of coal m with a sulfur content ≤1.3%, the total contribution of all such single types of coal m to the sulfur content of coke is denoted as S. t,d焦a :

[0045] S t,d焦a =∑[S t,dm焦1 ×Xm×Km / ∑(XiKi)]

[0046] =∑[(-1.801×V dm煤 +112.4)×S t,dm煤 ×Xm / ∑(XiKi)].

[0047] 2) For a single type of coal i, V daf <28%, S t,d煤 For single-type coals with sulfur content >1.3%, the total contribution of all such single-type coals n to the sulfur content of coke is denoted as S. t,d焦b :

[0048] S t,d焦b =∑[S t,dn焦2 ×Xn×Kn / ∑(XiKi)]

[0049] =∑[(-2.1052×V dn煤 +110.03)×S t,dn煤 ×Xn / ∑(XiKi)].

[0050] 3) Sulfur content of coke produced from blended coal: S t,d焦总 =S t,d焦a+ S t,d焦b .

[0051] The above is a method for predicting the sulfur content of coke suitable for blending with high-sulfur coal, which will be used to predict the sulfur content of V. daf ≥28% or V daf <28%, S t,d煤Coal with sulfur content ≤1.3% has coke sulfur content and V daf <28%, S t,d煤 The prediction of coke sulfur content in coal types with a sulfur content of >1.3% can effectively correct the prediction deviation of coke sulfur content after the blending of high-sulfur coal, so that the prediction deviation of coke sulfur content is controlled within 0.1%, which is beneficial to blast furnace production operation.

[0052] Example:

[0053] Step 1: The coal types blended by a certain coking plant are: gas coal, gas-rich coal, 1 / 3 coking coal, coking coal No. 1, high-sulfur coking coal No. 2, coking coal No. 1, coking coal No. 2, high-sulfur coking coal No. 3, lean coal No. 1, and high-sulfur lean coal No. 2. The coal quality analysis data of each coal type are shown in Table 1.

[0054] Table 1 Experimental data for a single type of coal

[0055]

[0056]

[0057] Step 2: Prediction of sulfur content in coke from a single type of coal:

[0058] Based on the volatile matter and sulfur content of each individual type of coal, V daf ≥28%; V daf <28%, S t,d煤 ≤1.3% coal, S t,d焦1 =(-1.801×V) d煤 +112.4)×S t,d煤 V daf <28%, S t,d煤 >1.3%, St,d 焦2 = (-2.1052×V) d煤 +110.03)×S t,d煤 The predicted sulfur content of coke for each type of coal is shown in Table 2.

[0059] Table 2. Prediction of sulfur content in coke from single types of coal.

[0060]

[0061]

[0062] Note: V in the table d焦 =1.5%.

[0063] Step 3 involves predicting the sulfur content of coal coke and optimizing the coal blending ratio.

[0064] Table 3. Benchmark Coal Blending Scheme and Coke Sulfur Content Prediction

[0065]

[0066]

[0067] Table 4. Adjustment Scheme 1 and Coke Sulfur Content Prediction (High-sulfur coking coal replacing low-sulfur coking coal)

[0068]

[0069]

[0070] Table 5 Adjustment Scheme 2 and Coke Sulfur Content Prediction (Adding High-Sulfur Coking Coal Scheme #3)

[0071]

[0072]

[0073] Table 6 Adjustment Scheme 3 and Coke Sulfur Content Prediction (Including High-Sulfur Lean Coal Scheme)

[0074]

[0075]

[0076] As can be seen from the above schemes, in order to reduce coal blending costs, the company increased the sulfur content of coke from 0.58% to 0.70% or even 0.71%, while the blast furnace remained within a controllable range. Compared with the benchmark scheme:

[0077] Adjustment Plan 1 proposes to use 10% more high-sulfur coking coal with a sulfur content of 2.6% and 10% less high-priced low-sulfur coking coal.

[0078] Adjustment Plan 2 recommends using more high-sulfur coking coal with a sulfur content of 2.5% and less high-priced, low-sulfur, high-quality coking coal with a sulfur content of 5%.

[0079] Adjustment Plan 3 recommends using more high-sulfur lean coal with a sulfur content of 7% up to 2.7%, and less high-priced low-sulfur lean coal with a sulfur content of 6%.

[0080] The predicted sulfur content of coke differed from the actual value by only 0.1%, and the cost of coal blending was significantly reduced.

Claims

1. A method for establishing a predictive model for the sulfur content of coke mixed with high-sulfur coal, characterized in that, The high-sulfur coal refers to a single type of coal with a sulfur content of 1.3-3.0%, wherein the single type of coal is at least one of gas coal, gas-rich coal, fat coal, 1 / 3 coking coal, coking coal, and lean coal. The method includes the following steps: 1) Establishment of prediction models for coking sulfur content of different single types of coal: Let the total focal length be K, and let K = (100 - V) / 2. d煤 ) / (100-V d焦 )×100; where V d煤 = V daf煤 ×(100-A d煤 ) / 100; the V d煤 Volatile matter on a dry basis of coal, in units of %; V d焦 The volatile matter content of coke is expressed on a dry basis, in %; V daf煤 The volatile matter content of coal on a dry ash-free basis is expressed in % (%). d煤 Ash content of coal on a dry basis, expressed as % . For any single type of coal i, its total coke yield is denoted as Ki, which is: Ki = (100 - V) / ( ... di煤 ) / (100-V di焦 )×100, V di煤 =V dafi煤 ×(100-A d煤 ) / 100; where V di煤 V is the dry basis volatile matter of a single type of coal i. dafi煤 V is the dry ash-free volatile matter of a single type of coal i. di焦 The dry basis volatile matter of coke prepared from a single type of coal i; The coking sulfur content of any single type of coal i is predicted according to the sulfur content and volatile matter content of that single type of coal i, respectively, using the following models: 11) For a single type of coal i, V daf ≥28% of a single type of coal m, or V daf <28% and S t,d煤 For a single type of coal m with a content ≤1.3%, let S t,d焦1 = (-1.801×V) dm煤 +112.4)×S t,dm煤 / Km; 12) For a single type of coal i, V daf <28% and S t,d煤 >1.3% of a single type of coal n, let S t,d焦2 = (-2.1052×V) dn煤 +110.03)×S t,dn煤 / Kn; Where S t,d焦1 S represents the sulfur content in coke obtained from any single type of coal (m), expressed in % (%). t,dm煤 Sulfur content in any single type of coal m, expressed in %; S t,d焦2 S represents the sulfur content in coke obtained from any single type of coal (n) after coking, expressed in % (%). t,dn煤 The sulfur content in any single type of coal n is expressed as % (%). The sets {m} of m, {n} of n, and {i} of i satisfy the following relationships: {m}≤{i}, {n}≤{i}, {m}+{n}={i}; the sets {Km} of Km, {Kn} of Kn, and {Ki} of Ki satisfy the following relationships: {Km}≤{Ki}, {Kn}≤{Ki}, {Km}+{Kn}={Ki}. 2) Establishment of a prediction model for coke sulfur content using high-sulfur coal: Let Xi be the proportion of any single coal i in the blended coal, then the total coke yield Ki = (100 - V) / ( ... di煤 ) / (100-V di焦 ) ×100; The coking rate of all single coal i after forming blended coal is: ∑XiKi; The proportion of any single coal i in the blended coal coking to the total coking of the blended coal is: XiKi / ∑(XiKi); 21) For a single type of coal i, V daf ≥28% of a single type of coal m, or V daf <28% and S t,d煤 For a single type of coal m with a sulfur content ≤1.3%, the total contribution of all such single-type coals m to the sulfur content of coke is denoted as S. t,d焦a : Let S t,d焦a =∑[S t,d焦1 [×Xm×Km / (∑XiKi)]; 22) For a single type of coal i, V daf <28% and S t,d煤 For single-type coal with a sulfur content >1.3%, the total contribution of all such single-type coals n to the sulfur content of coke is denoted as S. t,d焦b : S t,d焦b =∑[S t,d焦2 ×Xn×Kn / ∑(XiKi)] The set {Xm} of Xm, the set {Xn} of Xn, and the set {Xi} of Xi satisfy the following relations: {Xm}≤{Xi}, {Xn}≤{Xi}, {Xm}+{Xn}={Xi}; 23) Sulfur content (S) in coke obtained from blended coal coking t,d焦总 for: S t,d焦总 =S t,d焦a+ S t,d焦b 。 2. The method for establishing a coke sulfur content prediction model using high-sulfur coal according to claim 1, characterized in that, High-sulfur coal refers to a single type of coal with a sulfur content of 2.0 to 3.0%.

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