煤泥_煤矸石混燒技術(shù)在循環(huán)流化床鍋爐上的應(yīng)用

1、收稿日期: 20021224煤泥、煤矸石混燒技術(shù)在循環(huán)流化床鍋爐上的應(yīng)用李 玉,東野廣磊,李叢峰(新汶礦業(yè)集團(tuán)公司,山東泰安 271233摘 要 簡單介紹了山東新汶礦業(yè)集團(tuán)公司在130t/h 循環(huán)流化床(CFB鍋爐上進(jìn)行的煤泥、煤矸石混燒試驗(yàn),提出了摻燒煤泥的最佳方式及應(yīng)采取的措施。幾個月的運(yùn)行表明,CFB 鍋爐摻燒煤泥不但技術(shù)上可行,而且還具有明顯的經(jīng)濟(jì)效益和環(huán)境效益。關(guān)鍵詞 循環(huán)流化床(CFB鍋爐;煤泥;煤矸石;混燒中圖分類號TK229.6 文獻(xiàn)標(biāo)識碼A 文章編號10023364(200309004902 山東新汶礦業(yè)集團(tuán)公司華豐煤礦是一座具有百年開采歷史的老礦,建有裝機(jī)容量37MW 的煤

2、矸石熱電廠一座,其中有3臺35t/h 和1臺130t/h C FB 鍋爐。近幾年來,為提高煤炭質(zhì)量,洗煤廠的入洗量增大,導(dǎo)致煤泥、煤矸石產(chǎn)量上升。為有效利用煤炭資源,該公司在130t/h CFB 鍋爐上進(jìn)行了煤泥、煤矸石混燒試驗(yàn),經(jīng)過幾個月的運(yùn)行,證明在現(xiàn)用的CFB 鍋爐摻燒煤泥,不但技術(shù)上可行,而且還具有明顯的經(jīng)濟(jì)效益和環(huán)境效益。1 系統(tǒng)構(gòu)成華豐煤矸石熱電廠130t/h CFB 鍋爐系濟(jì)南鍋爐廠生產(chǎn)的YG 130/3.82M 6型中溫中壓、單汽包、自然循環(huán)鍋爐,其循環(huán)燃燒系統(tǒng)由燃燒室、爐膛、水冷旋風(fēng)分離器、返料器組成。爐膛為膜式水冷壁結(jié)構(gòu),兩級過熱器,中間設(shè)一級噴水減溫器,尾部設(shè)二級省煤器和

3、一、二次風(fēng)預(yù)熱器;點(diǎn)火方式為床下點(diǎn)火,由4臺刮板給煤機(jī)爐前正壓給煤;含灰煙氣經(jīng)旋風(fēng)分離器分離,大部分物料經(jīng)返料器返回爐膛循環(huán)再燃,隨煙氣排走的微細(xì)顆粒被電除塵器收集。原設(shè)計煤種為以煤矸石為主的低熱值燃料(Q net,v =12146kJ/kg。2 混燒試驗(yàn)2.1 煤泥泵送系統(tǒng)煤泥泵送系統(tǒng)由刮板機(jī)、攪拌機(jī)、NBS20型濃料泵、煤泥輸送管道等構(gòu)成。濃料泵可由就地泵房和鍋爐熱控室DCS 控制。洗煤水漿經(jīng)洗煤廠壓濾機(jī)脫水后,經(jīng)輸送皮帶、刮板機(jī)送入攪拌機(jī)進(jìn)行攪拌,水分控制在30%35%,然后由濃料泵通過煤泥輸送管道將煤泥輸送至鍋爐爐頂,從爐頂落入鍋爐燃燒室燃燒。為使煤泥能從爐頂落入燃燒室,在鍋爐頂部燃燒

4、室上方開孔,將煤泥輸送管道伸入鍋爐(由于此處為負(fù)壓區(qū),只采取簡單地封堵措施即可。煤泥輸送管道長約350m,爬高約40m 。2.2 混燒機(jī)理CFB 鍋爐在正常運(yùn)行時約有1m 左右的料層,床溫一般保持在850e 950e 。床料基本是由煤矸石燃燒后形成的爐渣,密度較大,耐磨性較好,而煤泥自身灰分較低、密度較小。煤泥進(jìn)入爐頂,形成塊狀落下,爐頂距布風(fēng)板約有30m 的距離,考慮煙氣行走帶來的阻力,大約需要3s 的時間,這足以使煤泥燃燒。 技術(shù)交流熱力發(fā)電#2003(9o 由于煤燃燒具有爆裂的性質(zhì),煤泥塊又具有良好的破碎性,因此,塊狀煤泥在下落的過程中碎裂燃燒,待落到布風(fēng)板時,已經(jīng)變成小塊,不足以糊到布

5、風(fēng)板上。另由于密度的差異,小塊煤泥將/漂浮0在沸騰層中燃燒,不會沉積在布風(fēng)板上影響鍋爐的流化質(zhì)量,也不會導(dǎo)致局部流化效果變差而造成結(jié)焦。入爐煤泥、煤矸石工業(yè)分析見表1。表1煤泥、煤矸石工業(yè)分析項(xiàng)目M ar/%M ad/%A ad/%V ad/%Q net,v/kJ#kg-1入爐煤泥33.20.945.320.614642煤矸石 6.350.4275.5114.046025原煤8.820.3419.5229.42231312.3試驗(yàn)結(jié)果為了保證鍋爐的出力,在運(yùn)行調(diào)節(jié)中除了常規(guī)操作外,還要特別注意以下事項(xiàng):(1保證各刮板給煤機(jī)運(yùn)轉(zhuǎn)正常;(2各安全閥經(jīng)試驗(yàn),確認(rèn)動作正常;(3風(fēng)機(jī)、給水等各項(xiàng)聯(lián)鎖試驗(yàn)

6、良好;(4煤泥水分控制在35%以下。試驗(yàn)共分為3步:(1在煤矸石中添加部分原煤,使煤矸石與原煤混合后發(fā)熱量達(dá)12550kJ/kg,穩(wěn)定鍋爐各項(xiàng)參數(shù);(2按2B3的比例摻入煤泥,降低刮板給煤機(jī)給入量,給入燃料的發(fā)熱量保持在12550kJ/kg,穩(wěn)定鍋爐各項(xiàng)參數(shù);(3保持煤泥的給入量,逐漸降低原煤量,增加煤矸石量,使混合入爐燃料發(fā)熱量為9 802kJ/kg,穩(wěn)定鍋爐各項(xiàng)參數(shù)。主要試驗(yàn)數(shù)據(jù)見表2。表2主要試驗(yàn)數(shù)據(jù)項(xiàng)目燃料熱值/kJ#kg-1主蒸汽壓力/MPa主汽溫度/e爐膛負(fù)壓/Pa煙氣氧量/%床溫/e排煙溫度/e料層差壓/kPa返料溫度/e風(fēng)室風(fēng)壓/kPa負(fù)荷/t#h-1煤矸石+原煤12550 3

7、.63.7440445-55-7012.112.79309501401457.57.89409507.67.8130132煤矸石+煤泥12550 3.63.8440445-40-5511.211.89309501401457.67.89559707.57.7131134煤矸石+煤泥9802 3.63.7440445-30-5011.612.39309501411457.57.89509607.57.7130132在風(fēng)量不變的情況下,風(fēng)室壓力越高表明料層越厚,運(yùn)行中維持正常風(fēng)量不變情況下,風(fēng)室壓力應(yīng)盡量維持在上述范圍內(nèi);同時,在運(yùn)行中盡量保持料層厚度,以免造成煤泥沉積,保證鍋爐穩(wěn)定運(yùn)行,這就要求

8、鍋爐運(yùn)行人員勤放渣、少放渣。床溫的調(diào)節(jié)應(yīng)采取調(diào)節(jié)入爐煤矸石量的方法,不要利用煤泥給入量來調(diào)節(jié)。此外,應(yīng)要求運(yùn)行人員加強(qiáng)監(jiān)視,增強(qiáng)責(zé)任心,一旦發(fā)生床溫升高,應(yīng)迅速減少煤泥的給入量,避免因調(diào)整不及時而造成爐床結(jié)焦,進(jìn)而導(dǎo)致返料器結(jié)焦的事故。3效果(1煤泥與相同發(fā)熱量的原煤相比較,價格約低130元/t,除去煤泥泵送系統(tǒng)所耗電費(fèi)、設(shè)備折舊費(fèi)、維護(hù)等費(fèi)用,每燃燒1t煤泥可節(jié)約燃料費(fèi)用約100元,如全年消耗8萬t煤泥,則可為電廠減少燃料支出約800萬元,效益相當(dāng)可觀。(2C FB鍋爐燃燒煤泥,避免了洗煤水外流造成的環(huán)境污染,同時也減輕了因煤泥堆放、儲存、運(yùn)輸帶來的煤塵污染,為華豐煤礦洗煤廠的正常運(yùn)行創(chuàng)造了

9、良好的生產(chǎn)條件,提高了煤礦的經(jīng)濟(jì)效益和環(huán)境效益。(3擬再增加1臺25m3/h的煤泥泵,并將煤泥泵房移至廠區(qū)以內(nèi),減少煤泥輸送管道長度約為120m,同時也減少了因管路過長、拐角過多造成的管道堵塞。(4煤泥、煤矸石混燒技術(shù)的成功應(yīng)用,為新汶礦業(yè)集團(tuán)公司其它矸石熱電廠、煤泥熱電廠成功燃用煤泥奠定了良好的基礎(chǔ),目前已有4臺130t/h CFB鍋爐采用了該技術(shù),另有6臺35t/h、4臺75t/h C FB鍋爐正在改造,以增加煤泥系統(tǒng)。歡迎訂閱歡迎投稿歡迎刊登廣告技術(shù)交流 p u熱力發(fā)電#2003(9pan si on of th e rotor,an d pr odu cin g ther mal st

10、ress.A fter the pad of bear ing p ed estal at th e said e nd be ing re paire d th rough scr api ng,th e abovmen tion ed p rob lem havin g bee n solved .ANA LYSIS OF SEVERAL KEY ISSUES ON REDUCING NO x EMISSION BY REBURNING TERTIARY AIR WITH FINELY -PUL -VER IZED COAL XU Zhang et al (42,Th e i nflu e

11、n cin g factors up on re bu rn ing fin elyp ul ve rize d coal and the featu res of re bu rn ing ter ti ary ai r have be en an alyse d,an d a tech n ical sc heme for reb ur ni ng the ter tiary air be ing p u t forw ard on the b asis of said an alysis.The con cen trator of fi nely -p ul verize d coal

12、has be en selec te d,an d th e d istr ibu tion of excess ai r coefficie nt for reb ur nin g the fin ely -p ul ve r -ized coal be ing de termin ed,solvin g c omp aratively w ell some face d p roble ms to u se te rtiary air for reb ur nin g.Th e r esu lts obtain ed h ave prac tical gui di ng effect fo

13、r reb ur ni ng tertiary air d esign.OPTIM UM C OMBUSTION CONTROL OF CFB BOILERS YA NG Yong et al (47,Mai n parameters o f opti mu m comb ustion con trol for cir cul ati ng flu idi zed b ed (FCBb oile rs h ave b een presen ted ,and optimu m combu tion c ontrol of 75t/h CF B b oilers in a pow er p lan

14、 t b ein g carri ed out.Practice show s that,u nd er p rese nt ope ration le vel of man y d omesti c C FB boi lers,th rough optimu m comb ustion con trol,the stabil ity of b oiler op eration can ob viously be imp roved i n a comp arativel y lar ge r ange,solvin g or r elaxin g trou b lesome p rob le

15、ms,su ch as low b oiler th ermal effici enc y,sh ort oper ati ng p eriod ,b ad oper ating stabil -ity,high spe cific ele ctric en ergy con sup tion of au xiliary eq ui pmen ts,an d se rious boil er ab rasion etc.,havin g re mar kab le e conomic be ne fits.APPLICATION OF M UD -COAL AND GANGUE M IX ED

16、 BURNING TECHNOLOGY ON A C FB BOILER LI Yu et al (49,Test of mu d -c oal an d gangu e mixed b u rni ng on a 130t/h circu latin g flui diz ed b ed (CF Bboile r o f X inw en Mini ng In d ustry G roup C ompan y,S han don g Pr ovinc e,has bee n br iefly p resen ted,an d the op timal mode of ad mixin g m

17、ud -coal as w ell as measure s must be tak en b ein g pu t for ward .The op eration in several mon thes sh ows that the mu d -coal ad mi xe d b u rni ng is not onl y tech n ically feasi ble ,bu t also h as econ omi c an d en viron me ntal be nefi ts.CA USE A NALYSIS OF ROLLER -C ASING BREAKAGE FOR M

18、V M 25R TYPE COAL PULVERIZER Y ANG Ning et al (51,S even rol ler -casin gs o f MV M 25R type coal pu lveri zers all ocated to b oiler s of tw o u n its in Zhu hai Pow er Plan t h ave bee n br oken early or later be fore re achi ng the d esigne d se rvice -l ife of 12000h .The macrostru ctu re analys

19、is an d th e me tal lograph ic examin ation of brok en su rface show ,the main cause of th e roll er -casi ng b reakage is the b ad q ual ity of manu -fac ture.In ord er to p reven t th e r ol ler -casin g from b reak age,the tec hn ology of manu factur ing roll er -casings h as b een i mproved ,an

20、d the h ydrc ul ic oil pre ssur e ap p lied on roller s b ein g r eadju ste d.IM PROVEMENT OF EXPANSION SYSTEM FOR 200MW UN IT BY USING SELF -LUBRACATING SLIPPERS ZHANG Yong -jun et al (54,D irec ting against th e un smooth ly exp and in g p rob lem of the sl idi ng pi n system in c entral b earin g

21、 b ox of a 200MW un it at Hu angshi Pow er G ene ration CO Ltd ,Hub ei Provi nce,the cau ses lead in g to u n smooth cloggin g of th e sl idi ng pin an d d eformation of th e table -p late,as well as th eir in flu enc e u p on ove rtempe rature of the b earin g shoes have bee n examine d an d anal y

22、sed ,and th e reliab il ity of sli din g p in syste m be ing en han ced b y u si ng sel f -lu b ricati ng grap h ite sli pp ers.OPTIM AL CONDITIONS OF DUAL -PUM P OPERATION FOR CIRCULATING -WATER PU MPS SHENG Huan -cheng et al (57,Th e in fuen ci ng factors an d op timal con diti ons for c han ging

23、sin gle -pu mp op eration to d ual -pu mp ope ration con cer nin g mixed -flow type c ircu latin g -w ater p ump s of a 300MW un it h ave b een discu ssed ,so as to en han ce the econ omi c aspec ts in ope ration of c ircu latin g -w ater pu mps.ARTIFICIAL LABORATORY BASED ON INTERNET FOR REMOTE V I

24、RTUAL THERMOTECHNIC CONTROL Y ANG Yi -rong et al (60,In ord er to save large amou n t of ti me an d effort con su med for rep eatedl y grop ing and te stin g b efore pu ttin g th e c ontrol system i nto op eration ,as we ll as ove rcome th e limitation of spac e an d time i n the fiel d,an d artific

25、 ial laboratory based on In tern et for re mote virtu al the rmote chn ic con trol has been design ed .The struc ture an d fu nction s of the h ard ware,the re alization of system commun ication ,as we ll as the str uctu re of th e arti ficial so ftw are ar e d escrib ed in detail .STUD Y ON MONITOR

26、ING LOC AL CORROSION OF COND ENSER .S BRASS TUBES IN THERM AL POWER PLANTS SONG Jing -xia et al (63,Th e ju dge me nt of br ass tu be s .local corr osion b y u si ng join tly tw o e lectroch emical test me thod s,n amely the p ote ntial mon itorin g an d th e lin ear polari zation,has b een stu di e

27、d u nd er l aboratory cond ition s.The re su lts show ,w he n p itting corr osion oc cur red on the b rass su rface,the p olarizati on resistance of elec trode w as obvi ously dec rease d,an d th e corrosion p o -tenti al b ein g also ob viously lowe red.Th is ru le can b e u sed to moni torin g the

28、 d egree of p ittin g corr osion on th e matall ic su rface.IM PROVEMENT OF AUTOMATIC INTERFAC E TENSIOMETER AND APPROACH TO TEST M ETHOD THEREOF LI Ye -feng et al (65,In view of the de ficie ncy existing in test meth od of origi nal automatic in terface tensiometer,some i mp rovemen t measu res hav

29、e be en suggested as follow s:(1ad optin g magn etic pot seale d sen sor ;(2u si ng equ al -space mu ltip le p oints .cali brati on;(3add in g comp en sation fun ction to th e ambie nt tempe rature ;(4maki ng the an alysis meth od to be p ro -gr ammed b y mean s of sin gl e ch ip p rocessor .A fte r

30、 improvemen t,th e measu rin g accu racy of th e sai d ten siome te r has bee n greatly e nh ance d,solvin g the p rob lem of te st method sti pu -lated in p resen t N ational S tan d ar d havin g b een r estr icted b y th e amb ien t temp eratur e.DESIGN AND CALC ULATION OF OIL -PURIF YING SYSTEM F

31、 U Zhong -qing et al (67,Tak ing syn ch ronou s ope ratiion of b oth oil -ap p lyin g e qu ip me nt an d oil -p ur ifying e qu ip me nt as examp le,th e p rin cip le an d method of design and c alcu lation for oil -pu rifyin g equ ip -me nt have bee n descri bed ,an d p ractic al examp le of calc ul

32、ati ion b ein g gi ven.It is obtain ed from th eori ti cal analysis that the me thod s w hic h can be u se d to en su re th e qu ality of oil are as foll ows:(1i ncre asin g th e vol ume of oil tank ;(2decr easi ng the impu riti es mixed -i n oil;(3se lectin g an d usin g h igh ly e ffec tive oi l -

33、pu ri fyi ng e qu ip me nt;(4se lectin g an d u sing oil -p uri fying equ ip men t w ith large flow qu an tity.APPLICATION OF HV VARIABLE FREQUENCY SPEED CONTROL TECHNOLOGY FOR ENERGY -SAVING IN FORC ED D RAFT FANS OF 670t/h BOILERS TIAN Jian -xu et al (70,Th e b asi c p rin cip les of variab le freq u enc y spee d con trol and th e advan tage s