流化床燃燒充分,爐內(nèi)燃燒控制較好,但煙氣中灰塵量大,操作復(fù)雜,運(yùn)行費(fèi)用較高,對燃料粒度均勻性要求較高,需大功率的破碎裝置,石英砂對設(shè)備磨損嚴(yán)重,設(shè)備維護(hù)量大。易產(chǎn)生結(jié)焦,系統(tǒng)連續(xù)運(yùn)行能力較低。
垃圾發(fā)電回轉(zhuǎn)式焚燒爐簡介:
工作原理:回轉(zhuǎn)式焚燒爐是用冷卻水管或耐火材料沿爐體排列,爐體水平放置并略為傾斜。通過爐身的不停運(yùn)轉(zhuǎn),使?fàn)t體內(nèi)的垃圾充分燃燒,同時向爐體傾斜的方向移動,直至燃盡并排出爐體。
特點(diǎn):設(shè)備利用率高,灰渣中含碳量低,過??諝饬康停泻怏w排放量低。但燃燒不易控制,垃圾熱值低時燃燒困難。對于垃圾量比較少的地區(qū)可以采用該工藝。
和利時垃圾焚燒領(lǐng)域ACC控制方案介紹:
ACC(Automatic Combustion Control)——自動燃燒控制
ACC自動控制主體分為六部分:蒸汽流量控制、垃圾料層控制、燃燒位置控制、爐膛溫度控制、煙氣含氧量控制、爐膛溫度850℃停留2S控制。
通過ACC自動控制最終實(shí)現(xiàn)了垃圾穩(wěn)定燃燒、爐膛溫度得到保證、主蒸汽產(chǎn)生量和垃圾供應(yīng)得以穩(wěn)定、爐渣熱灼減率最小化、污染物的排放得以降低。
成功實(shí)施了多家國內(nèi)外爐排廠家的ACC 控制,目前DCS實(shí)現(xiàn)ACC控制的有: 日本日立造船技術(shù)、日本荏原技術(shù)、重慶三峰技術(shù)、綠色動力技術(shù)、中信康恒技術(shù)、無錫華光等。
和利時垃圾焚燒領(lǐng)域ACC投入前后效果及經(jīng)濟(jì)效益對比:
垃圾發(fā)電ACC投入前后數(shù)據(jù)對比
1.整體經(jīng)濟(jì)效益提高10%以上。
2.減少操作人員勞動強(qiáng)度20%以上。
3.針對國內(nèi)外各廠家爐排制作了專用的ACC控制功能塊及畫面。
4.針對國外ACC方案不完全適用于國內(nèi)垃圾情況的特點(diǎn),結(jié)合以往調(diào)試經(jīng)驗(yàn),對國外ACC方案進(jìn)行微調(diào),以確保ACC順利投入。
ACC投入后系統(tǒng)運(yùn)行截圖
ACC投入后垃圾投入量截圖
ACC投運(yùn)后60個小時內(nèi)的主蒸汽流量及停留兩秒溫度曲線。
of normal patch testing.
Do ICS / SCADA users want to patch
The last example emphasizes a key problem of using patch to solve the security of control system. Many users are reluctant to install patches for their controllers because it can degrade services and increase downtime. In the last example, the supplier who privately informed the author pointed out that for the released patches, they have only 10% download rate.
The author's experience in dealing with ICs security products confirms the fact that patch acceptance in this field is low. In September 2010, version 1.6 of doveno industrial safety system was released. This upgraded version solves a lot of security and performance problems reported by users during the 30 day free trial period. Due to the low initial acceptance rate, all registered users registered through multiple emails to obtain a 30 day trial period again. Two months later, only 30% of domino users downloaded the free upgrade.