Management of hazardous waste in Thailand: present situation and future prospects

 This paper deals with the present scenario of hazardous waste management practices in Thailand, and gives some insights into future prospects. Industrialization in Thailand has systematically increased the generation of hazardous waste. The total hazardous waste generated in 2001 was 1.65 million tons. It is estimated that over 300 million kg/year of hazardous waste is generated from nonindustrial, community sources (e.g., batteries, fluorescent lamps, cleansing chemicals, pesticides). No special facilities are available for handling these wastes. There are neither well-established systems for separation, storage, collection, and transportation, nor the effective enforcement of regulations related to hazardous wastes management generated from industrial or nonindustrial sectors. Therefore, because of a lack of treatment and disposal facilities, these wastes find their way into municipal wastewaters, public landfills, nearby dump sites, or waterways, raising serious environmental concern. Furthermore, Thailand does not have an integrated regulatory framework regarding the monitoring and management of hazardous materials and wastes. In addition to the absence of a national definition of hazardous wastes, limited funding has caused significant impediments to the effective management of hazardous waste. Thus, current waste management practices in Thailand present significant potential hazards to humans and the environment. The challenging issues of hazardous waste management in Thailand are not only related to a scarcity of financial resources (required for treatment and disposal facilities), but also to the fact that there has been no development of appropriate technology following the principles of waste minimization and sustainable development. A holistic approach to achieving effective hazardous waste management that integrates the efforts of all sectors, government, private, and community, is needed for the betterment of human health and the environment. Received: February 26, 2001 / Accepted: October 11, 2002     

Characteristics of large cooking oil pool fires and their extinguishment by water mist

Large cooking oil pool fires, occurring in industrial oil cookers, present a severe hazard to food processing plants due to their size and the large amount of hot oil involved. This paper reports a series of full-scale fire experiments conducted in a large industrial oil cooker mock-up. The characteristics of large cooking oil pool fires and the effect of oil depth and hood position in the oil cooker on fire growth were studied. The use of water mist for extinguishing large oil pool fires and their extinguishing performance under different discharge pressure and with different types of water mist systems were investigated. Experimental results showed that the cooking oil underwent a substantial expansion in volume during heating. The fires developed quickly once the oil auto-ignited. The fire growth rate was affected by the oil depth in the pan and the hood position in the oil cooker. The water mist fire suppression systems effectively extinguished large cooking oil fires and prevented them from re-igniting. Their extinguishing performance was determined by the type of water mist system, discharge pressure and hood position in the oil cooker.     

RAPID-N: Rapid natech risk assessment and mapping framework

Natech accidents at industrial plants are an emerging risk with possibly serious consequences. For the mitigation of natech risk, authorities need to identify natech prone areas in a systematic manner. In order to facilitate probabilistic natech risk mapping, a unified methodology was developed that is based on the estimation of on-site natural hazard parameters, determination of damage probabilities of plant units, and assessment of probability and severity of possibly triggered natech events. The methodology was implemented as an on-line, extensible risk assessment and mapping software framework called RAPID-N, which allows rapid local and regional natech risk assessment and mapping with minimal data input. RAPID-N features an innovative data estimation framework to complete missing input data, such as on-site natural hazard parameters and plant unit characteristics. The framework is also used for damage assessment and natech consequence analysis, and allows easy modification of input parameters, dynamic generation of consequence models according to data availability, and extension of models by adding new equations or substituting existing ones with alternatives. Results are presented as summary reports and interactive risk maps, which can be used for land-use and emergency planning purposes by using scenario hazards, or for rapid natech consequence assessment following actual disasters. As proof of concept, the framework provides a custom implementation of the U.S. EPA's RMP Guidance for Offsite Consequence Analysis methodology to perform natech consequence analysis and includes comprehensive data for earthquakes. It is readily extendible to other natural hazards and more comprehensive risk assessment methods.     

污泥在堆肥及油污土壤修复中重金属形态的研究

污泥堆肥工艺是实现污泥减量化,无害化和资源化的重要手段。文章考察了污泥在堆肥前后四类重金属(铜、锌、铅和镉)形态的变化。结果显示,铜、锌、铅和镉在堆肥前后的总量变化不大,Cu、Zn主要以有机结合态和残渣态形式存在,而Pb、Cd主要以残渣态形式存在。堆肥处理过程中可交换态重金属都呈下降趋势,但各种重金属的可交换态变化幅度不同,以Zn和Cd下降幅度最大,Zn的可交换态由堆肥前的10.5%下降到堆肥后的4.8%;Cd的可交换态从堆肥前的3.2%下降到堆肥后的1.8%,下降比例超过和接近50%。随着向土壤中添加污泥及堆肥量的增加,小麦植株地上和地下部分重金属含量也相应增加,且地下部分含量高于地上部分,小麦中重金属含量在地下部与地上部之间的比值恒定,特别是Pd,Cd的地上和地下部分浓度比可分别达到130和15～20,经堆肥处理的污泥可以降低小麦对其中重金属的吸收。将污泥及堆肥腐熟品添加至石油污染土壤中,与对照相比土壤中的石油烃含量有一定幅度的下降,最大下降幅度为19.6%。处理一个月后重金属含量及其形态变化不大,Zn具有向铁锰氧化态转化的趋势。     

Airsolution液体在净化有机废气方面的应用

Airsoluton是一系列植物提取液复配而成的,这些植物提取液是含有气味的有机物,它们是从树、草和花等植物中提取的。这些有味的液体含有大量复杂的化合物,它们是绝大多数植物油的主要成分。本文根据Airsolution液体的氧化性,对处理含苯、甲苯和二甲苯的有机工业废气进行了净化研究,结果表明:Airsolution液体用于处理有机废气是可行的,处理后的苯、甲苯和二甲苯可实现达标排放。且该工艺具有运行费用低,投资少的特点。     

人粪便中温好氧堆肥过程的有机物降解特性研究

利用密闭式小型堆肥反应器,以锯末作为堆肥载体,采用批量反应的操作方式,在35℃的温控条件下进行了人粪便的中温好氧堆肥实验。结果表明,在14 d的堆肥反应周期内,粪便中以COD为参数的有机物去除率可达到70%左右,且在10～12 d内基本完成有机物降解。在中温条件下,堆体容易保持适宜的含水率和pH值,维持适宜微生物繁殖生长的条件。运用磷脂法进行堆肥过程中微生物总量的分析,表明在一个堆肥周期内,微生物经历了环境适应期、稳定增殖期、生物量下降期等3个阶段,这一微生物繁衍规律与有机物的去除密切相关。与高温堆肥相比,中温堆肥能够减少设备加热的能量消耗,是缺水地区人粪便处置的可选方法之一。     

接种微生物与人粪便同步连续投加对好氧堆肥效果的影响简

利用新型梨形筒式好氧堆肥反应器,在通风量为3.0 L/min,搅拌频率为5 min/h的条件下,就不接种微生物、接种土著菌种、枯草芽孢杆菌与酵母菌时人粪便连续投加好氧堆肥效果进行了对比。堆制20 d即2个运行周期中各堆体的温度、含水率、COD、总氮、pH值与GI等的变化表明,接种微生物可以显著提高堆体的升温速率与堆体平均温度、COD降解率、GI（P<0.01）,堆肥可迅速达到完全腐熟。接种土著菌种效果最为明显（P<0.01）,其后相继为枯草芽孢杆菌与酵母菌。接种土著菌种可使堆体温度在50℃以上维持18 d,第8天COD降解率达到61.17%、总氮损失率为25.75%,第6天时GI达到108.22%。     

工业烟气氨排放特征及其对颗粒物污染形成影响

氮氧化物（NO_X）超低排放控制背景下,工业烟气氨（NH₃）逃逸问题被广泛关注。为探究重点行业NH₃逃逸现状及其对空气质量的影响,本研究于2022年3—6月针对江苏省7个重点行业烟气NH₃排放进行了监测,并针对NH₃逃逸严重的4条生产线测试其可凝结颗粒物（CPM）的排放特征。研究结果显示,68家企业的NH₃排放质量浓度为0.7～65.4 mg/m³,热电、日用玻璃行业的NH₃逃逸问题突出,其NH₃平均质量浓度分别为37.4,39.2 mg/m³。采用选择性非催化还原（SNCR）脱硝设施的工业烟气NH₃排放质量浓度分别是采用选择性催化还原（SCR）和SNCR+SCR联合技术的2.36,1.42倍;NH₃逃逸现象严重的生产线的排气筒出口处CPM质量浓度达到717～1 322 mg/m³,抵消了脱硫、脱硝和除尘带来的减排效果,对细颗粒物（PM_2.5）污染有直接贡献。研究结果可对我国二次颗粒物来源与治理方向提供支撑。     

Apportioning aldehydes: Quantifying industrial sources of carbonyls

<正>In their recent Journal of Environmental Sciences publication,Wang and colleagues provide field evidence that industrial activities can contribute substantially to atmospheric carbonyl concentrations(Wang et al.,2015).These results may helpto explain underestimations of carbonyl emissions in currently available emission inventories,and highlight the need for an improved understanding of industrial sources of this class of compounds.In the atmosphere,carbonyl compounds photolyze to yield     

工业园区典型行业废水的理化性质及急性毒性

利用理化检测和发光细菌法对天津市某工业园区内16家行业典型企业的进出水进行理化分析和急性毒性试验.结果表明,16家企业原水水质较差,且废水的污染特征差异明显.发光细菌毒性试验表明,16家企业原水对发光细菌的急性毒性等级在重毒以上的比例占到81.25%.预处理后,废水的常规指标基本上满足园区污水处理厂收水标准,但部分企业出水中仍能检出一定浓度的非常规污染物.预处理后,企业废水的整体毒性得到有效削减,低毒和中毒的比例分别达到了25%和37.5%.相关性分析实验表明,企业原水急性毒性与各化学参数间均无相关性,企业出水的急性毒性则与化学需氧量（r=-0.589,Pr=-0.566,Pr=-0.670,Pr=-0.659,Pr=-0.684,Pr=-0.678,Pr=-0.682,P<0.01）具有显著相关性.将理化性质与急性毒性指标有机结合起来,能够更加全面、准确的判断工业废水水质状况.建议在制订工业园区纳管标准时设置急性毒性指标.