Composting of vinasse and cotton gin waste by using two different systems

Two composts were obtained by co-composting of a concentrated depotassified beet vinasse and cotton gin waste using two different aeration systems: static aerated pile (forced aeration provided by a blower whom operated in the positive mode) and windrow (turned pile). The composting mixtures were cotton gin trash (55%) and vinasse (45%) (dry weight). In static pile, the total amount of vinasse was added at the beginning of the process whereas, in windrow two additions of vinasse were performed. Differences in temperature changes between both composting systems were found: a faster increase of temperature in the windrow (54 °C at 7 days) than in the static pile (45 °C at 21 days) was observed. Probably in the static pile system, the compaction of the substrates made difficult the correct distribution of the air inside the pile. Moreover, after the second addition of vinasse a new thermophilic phase was started in windrow. The different aeration systems and the way of addition of vinasse could cause differences in organic matter (OM) degradation and in weight (22.6% for the static pile and 26.7% for the windrow) and gas losses during the process. Nevertheless, the composts obtained by the two systems had a high fertilizer value (25.1 g kg⁻¹ N; 3.2 g kg⁻¹ P₂O₅; 21.4 g kg⁻¹ K₂O; C/N8) for compost obtained in static pile and (16.2 g kg⁻¹ N; 3.4 g kg⁻¹ P₂O₅; 16.1 g kg⁻¹ K₂O; C/N 12) for compost obtained in the windrow). A high degree of stability was reached in the final composts. Composting of vinasse with cotton gin waste serves two objectives, disposal of wastes and recycling of waste components.     

棉花阴燃和明火燃烧特性的对比研究

利用锥形量热仪,选取不同辐射强度,分别在使用和不使用点火器条件下,对棉花进行了热辐射引燃实验,发现在热辐射强度大于6kW/m2的情况下,使用点火器时棉花发生明火燃烧,不使用点火器时棉花发生阴燃燃烧。实验分别测得了在两种燃烧形式下的引燃时间、热释放速率、质量损失速率一氧化碳生成率,结果表明:无论是发生阴燃还是明火燃烧,引燃时间均随着辐射强度的增加而减小,且引燃时间平方根的倒数与辐射强度成线性关系;热释放速率、质量损失速率的峰值和平均值均随辐射强度的增加而增加,但在同一辐射强度下,明火燃烧的峰值和均值均比阴燃燃烧时的大;明火燃烧的一氧化碳平均生成率随着辐射强度的增加而减小,阴燃燃烧的一氧化碳平均生成率随着辐射强度的增加而增加。     

培养温度对好氧法处理棉浆黑液的影响分析

对不同浓度的棉浆黑液分别在高温和中温条件下进行了好氧培养,并考察了各种COD的降解情况。结果表明：温度对棉浆黑液好氧处理的各种COD去除效果影响较大。对于低浓度棉浆黑液（CODtot≤10000mg／L）,30℃时,随着培养时间的延长,各种COD持续下降,CODtot和CODcol去除率最大分别可达55．7％和100％;而50℃时,CODtot去除率最高只能达到35．4％,且CODss和CODcol波动很大;对于高浓度棉浆黑液（CODtot≥10000mg／L）,中温条件更有利于好氧活性污泥发挥生物降解作用