“高压带机+好氧发酵”联用工艺在粪便污泥处理中的实践和研究

阮燕霞，杨文文，唐秀华，刘立文，黄健，魏宏斌

（上海中耀环保实业有限公司，上海    200092）

摘  要  河北省某粪便处理站收集并处理附近学校产生的粪便污水，原采用“絮凝脱水+好氧发酵堆肥”工艺，将粪便污泥处理至含水率84%左右进行好氧发酵堆肥。但含水率84%的粪便直接进行好氧发酵须添加大量的辅料，堆肥物料存在易板结、氧气传质效率低、运行成本高等问题，影响了堆肥成品质量。为提高粪便污泥好氧发酵效率及降低运行成本，在充分利用原有设备和场地的前提下，在原脱水工艺后端和好氧发酵工艺前端增加高压带式深度脱水工艺。该项目连续运行结果表明，经高压带式深度脱水工艺处理后，粪便平均含水率从84%降至59%以下，粪便减量率达61%以上，节省辅料量90 %以上，改造之后粪便减量效果和经济效益显著。

关键词  高压带机    深度脱水    粪便污泥    好氧发酵    减量

Practice and Research on the Combined Process of "High-pressure Belt Conveyor+Aerobic Fermentation" in the Treatment of Fecal Sludge

RUAN Yanxia

(Shanghai Zhongyao Environment Protection Industry Co. Ltd, Shanghai    200092, China)

Abstract   A fecal treatment station in Hebei Province collects and treats fecal wastewater generated by nearby schools. The original process use "flocculation dehydration+aerobic fermentation composting" to treat fecal sludge, and it’s treated to about 84% moisture content for aerobic fermentation composting. However, direct aerobic fermentation of feces with a moisture content of 84% requires the addition of a large amount of auxiliary materials. There are problems with composting materials such as easy solidification, low oxygen mass transfer efficiency, and high operating costs, which affect the quality of compost products. To improve the efficiency of aerobic fermentation of fecal sludge and reduce operating costs, a high-pressure belt deep dehydration process is added at the back end of the original dehydration process and the front end of the aerobic fermentation process, while fully utilizing the existing equipment and site. The continuous operation results of this project indicate that after being treated with high-pressure belt deep dehydration process, the average moisture content of feces decreases from 84% to below 59%, and the reduction rate of fecal sludge reaches over 61%, saving more than 90% of the amount of auxiliary materials. After the reconstruction, the fecal reduction effect and economic benefits is significant.

Keywords   high-pressure filter belt press    deep dewatering    fecal sludge     aerobic fermentation     reducing quantity

粪便污泥（Fecal sludge，FS）是一种由人类初始粪便、沙土、灰水混合部分消化后形成浆料等构成的粘稠状物质^{[1, 2]}，FS中含有大量的有害的细菌、病毒等，若处理不当，很容易造成细菌或病毒感染的传播^{[3, 4]}，同时化粪池FS中的COD、TN、TP和NH3-N含量分别可达1600mg/L、3724mg/L、988mg/L和2432 mg/L，若直接应用于土地利用，很容易对自然环境和人类健康造成威胁^[5]。另一方面，随着城市人口的快速增加，集中式的粪便处理中心需求不断增加，使集中处理的FS产量不断增加，因此FS的高效稳定无害化处理处置十分必要。

韩圩娟通过分析技术、经济、社会等10个评价因子构件的综合评价体系得出“絮凝脱水+好氧发酵+除臭”是目前国内FS处理处置的最佳工艺路线^[6]，但是经过固液分离后絮凝脱水FS含水率普遍在70-80%左右^[7]，FS减量不明显，同时好氧堆肥阶段添加的辅料较多，好氧堆肥运行费用较高。

针对上述问题，本文提出将高压带机应用于FS“絮凝脱水+好氧发酵+除臭”的整体工艺中，通过高压带机连续脱水，将FS含水率降低至60%以下，从而降低好氧堆肥的处理规模和降低运行费用。

1 案例简述

河北省某粪便处理站消纳附近学校产生的粪便污水，该粪便处理站设计粪便污水处理规模200吨/天，污泥浓度20g/L。粪便污水先经过化粪池处理后，上清液排入市政管网，输送至附近污水处理厂进一步无害化处理，吸粪车将剩余的固液混合物运送到该粪便处理站进行“絮凝脱水+好氧堆肥”。