钻井废水可生化性研究及处理技术探索

钻井废水是油气井开采钻探过程中产生的废水，钻井废水成分复杂，有机物浓度高、色度高、悬浮物浓度高，水质变化大，排放点分散，不经处理排放会污染环境，破坏生态。随着石油工业的不断发展和国家环保法律法规的日益严格，钻井废水的治理也越来越受到重视。如何采用经济有效的方法处理废弃钻井液，对油气井开采业的可持续发展具有重要意义。本论文以遂宁磨153 井的钻井废水为主要研究对象，在对废水进行絮凝沉降预处理和生物法处理探索的基础上，针对钻井废水可生化性差的特点，采用水解酸化和Fenton 试剂改善钻井废水的可生化性，对反应过程进行了比较详细的考察，对可生化性改善的机理进行了探索。主要研究结论如下：1 用PFS 和PAC 配制的混合混凝剂对钻井废水COD 的去除效果比较显著，在最佳条件下COD 的去除率可达75%，且絮体沉降速度较快，出水pH 保持中性；2 水解酸化法处理钻井废水可显著改善废水的可生化性。经48 小时水解酸化处理，钻井废水的理论BOD5可提高约22 倍，表观BOD5/COD值由0.004 提高到0.034。用接触氧化反应器处理经水解酸化处理后的废水，处理效果比较稳定，COD平均去除率达35.5%；3 研究了Fenton反应中各影响因子对废水COD去除率、BOD5/COD的影响并分析其作用机制，确定了最佳条件：初始pH为4.0，H2O2/Fe2+(摩尔浓度比)为20，H2O2/COD（质量浓度比）为1，反应时间为2 个小时。此条件下，废水的COD去除率约为40%，BOD5/COD值从0.002～0.003 提高至0.15～0.2，可生化性得到很大提高。本论文的主要创新点在于：1 以成分复杂、水质变化大的气井钻井废水为研究对象，从理论BOD 和表观BOD 两方面对水解酸化过程中废水可生化性的变化进行了分析；2 对Fenton 试剂改善钻井废水可生化性的过程、主要影响因素进行了比较详细的考察。本论文的研究成果，可为生物法处理钻井废水的深入研究提供理论依据。Drilling wastewater is produced in the process of oil-gas well drilling,because of its complicated composition, high concentrate of organic compound andsuspended solid, high chroma, levity of water quality and decentralization ofdischarge point, it pollutes environment seriously if discharged without treatment.With the development of petroleum industry and the issuing of more strict laws forenvironmental protection, it has been paid more and more attention on drillingwastewater treatment. It is of great importance for the sustainable development ofoil-gas well drilling to treat drilling wastewater by economical and effective methods.In this paper, drilling wastewater of Mo No.153 well in Suining was studied asthe main object. On the basis of research on pre-treatment with flocculant andbiological treatment, and according to the character of poor biodegradability, thedrilling wastewater was treated by hydrolytic acidification and Fenton’s reagent toimprove its biodegradability. The process and mechanism of biodegradabilitychanging were investigated. The primary conclusions are:1 It is effective to treat drilling wastewater with mixing PFS and PAC asflocculant. The removal rates of COD came up to 75% under optimal conditions, thesedimentation rate of flocculation is rapid, and the pH value of treated water remainedneutral;2 The biodegradability of drilling wastewater was highly improved afterhydrolytic acidification process. The theoretic BOD5 of drilling wastewater increasedby 22 times and its detected BOD5/COD ratio increased from 0.004 to 0.034 afterhydrolytic acidification for 48 hours. The wastewater after hydrolytic acidificationwas treated by biological contact oxidation reactor. Stable treatment performance was achieved, and the average removal rates of COD came up to 35.5%;3 The effects of various affection factors on the removal efficiency of COD andBOD5/COD radio in treating drilling wastewater by Fenton’s reagent wereinvestigated and the mechanism was analyzed. The optimal conditions were: initialpH of solution was 4.0, the molar ratio of H2O2 and Fe2+ was 20, the concentrationratio of H2O2 and COD was 1 and the reaction time was 120 min. Under the aboveconditions, the removal efficiency was about 40% and the ratio of BOD5 and CODincreased from 0.002 ¡« 0.003 to 0.15 ¡« 0.2. The biodegradability of drillingwastewater was greatly improved.The innovations of this thesis are:1 The drilling wastewater was taken as the research object which hascomplicated composition and variational water quality, and the changes ofbiodegradability were analyzed from theoretic BOD and detected BOD aspects duringhydrolytic acidification process;2 The biodegradability changing process and primary affection factors of drillingwastewater treating by Fenton’s reagent were investigated.The results of this study could provide theoretic foundation for further researchon biological treatment of drilling wastewater.

超声与磁粉强化含单宁废水生物处理研究

单宁是一种典型的有毒难降解污染物，在制革、造纸、制药、印染等行业废水中广泛存在，对水环境造成污染并且影响废水生物处理效果。本研究针对含单宁废水生物处理效率低、较高浓度时微生物受抑制且污泥容易膨胀等问题，采用超声和磁粉来强化含单宁废水生物处理，研究超声和磁粉对微生物活性、污染物去除及污泥沉降性能的影响，并对其作用机理进行了分析和探讨。 研究结果表明，活性污泥系统中单宁酸容积负荷可以达到1.8kgCOD/(m3·d)，单宁酸和COD去除率分别达到85.2%和79.6%，但如果负荷进一步增大则微生物活性迅速降低。系统在pH 5~8、温度20~35℃、DO>1 mg/L的条件下具有较好的单宁酸降解效果和处理稳定性。单宁降解动力学参数为：μmax =0.208h-1；Ks=226mg/L；Ki=522mg/L；kd=0.0092h-1；Y =0.594。 磁粉对系统处理效果和污泥沉降性能有一定的促进作用，且效果要优于外磁场。适宜的磁粉粒径和投加量分别为0.05~0.15mm和1.0g/L，COD去除率比对照系统提高6.4%，SVI降低28.6%，污泥絮体结构紧密。磁粉强化主要是通过其对污泥菌胶团的凝聚、吸附作用以及对微生物活性的强化作用实现。 在适当强度（0.4W/cm2）和辐照时间（20min）的超声作用下污泥絮体和细胞膜通透性增大，酶分泌也增多，系统的COD去除率比对照提高了8.8%，单宁酶酶活提高了11%。但超声也使污泥絮体结构松散，沉降性能下降，SVI比对照系统升高9.3%。 由于污泥流失加剧导致污泥浓度相对较低，声磁联合强化系统相对于磁粉强化系统其处理效果并没有提高。但相对于单纯活性污泥系统，声磁联合作用下系统处理效果、污泥沉降性能以及系统运行稳定性都得到明显改善。本研究为难降解废水的生物处理提供了一个新的思路。 Tannins are typical refractory and toxic pollutants that commonly exist in wastewater from dye, medicine, paper and leather industries and cause many problems associated with environmental pollution and biological treatment of wastewater. Biological treatment efficiency of tannin-containing wastewater is usually low owing to its biological toxicity and low biodegradability, microbes are usually inhibited under high tannin concentration and sludge bulking frequently occurs. In this study, ultrasound and magnetic powder were used to improve the biological treatment performance of simulated tannic acid-containing wastewater. The effects of ultrasonic irradiation and magnetic powder on microbial activity, tannic acid degradation rate and sludge sedimentation were investigated. The augmentation mechanisms were analyzed and discussed. The experimental results showed that the microbes were prominently inhibited under high tannic acid concentration, but moderate degradation efficiency can be maintained under a tannic acid load of up to 1.8kgCOD/(m3·d), with the tannic acid degradation and COD removal percentage of 85.2% and 79.6% respectively. The highest degradation rates and treatment stability were achieved at pH range of 5~8, temperature range of 20~35℃ and DO concentration of above 1mg/L. The kinetic parameters were estimated, including: μmax =0.208h-1；Ks=226mg/L；Ki=522mg/L；kd=0.0092h-1；Y =0.594. The microbial activity, tannic acid degradation rate and sludge sedimentation were improved by adding Fe3O4 magnetic powder, and the augmentation performance was better than external magnetic field. The appropriate particle size and dosage of magnetic powder were found to be 0.05~0.15mm and 1.0g/L, respectively, under which the COD removal percentage was improved by 6.4% and SVI value decreased by 28.6%, and compact floc structure was observed. This was mainly caused by the flocculation and adsorption effects of magnetic powder against sludge floc and the stimulation of microbial activity under appropriate magnetic field. Under appropriate ultrasonic irradiation (ultrasonic intensity 0.4W/cm2, ultrasonic irradiation time 20min), the permeability of floc and cell membrane are improved, transfer of substrate and oxygen were reinforced; meanwhile, more enzyme were produced by microbes under the slight damage caused by ultrasound. However, the floc structure became loose under ultrasonic irradiation, leading to relatively poor sedimentation, with the SVI value 9.3% higher than the control system. Although the magnetic powder-ultrasonic irradiation combined augmentation system showed no improvement in treatment performance compared with sole magnetic augmentation system owing to its relatively low sludge concentration, it guaranteed the stable operation of system, meanwhile the tannic acid degradation and sludge sedimentation were significantly improved compared with sole activated sludge system. This study gives a new idea for biological treatment of refractory wastewater.

非点源污染物细颗粒泥沙的絮凝-分散研究

细颗粒泥沙的絮凝-分散对土壤结构的稳定性，土壤中农用化合物的迁移以及侵蚀泥沙的输移、沉积有重要作用。文章概述了影响细颗粒泥沙絮凝-分散的几种主要因素——电解质种类及其浓度，矿物组成，有机质含量，pH值以及水流紊动等；指出了当前研究中存在的不足之处。

CaCl_2对细颗粒泥沙静水絮凝沉降的影响

细颗粒泥沙的絮凝或分散对土壤渗透性、土壤可蚀性有重要作用 ,是水土保持研究的重要内容。在 Ca Cl2 浓度为 0～ 1.0 mmol/L ,泥沙浓度为 10 g/L时 ,用吸管法研究了 Ca Cl2 对细颗粒泥沙絮凝沉降的影响。结果表明 :泥沙沉降分 2个阶段 ,分选沉降段和絮凝沉降段 ;在絮凝沉降段 ,Ca Cl2 浓度越大 ,絮凝沉降越快。但较高浓度时 ,细颗粒泥沙平均沉速反而随 Ca Cl2浓度增大而逐渐减小 ;泥沙浓度随时间呈指数衰减 ;细颗粒泥沙絮凝临界粒径为 0 .0 3mm。

细颗粒泥沙絮凝-分散在水土保持中的应用

简要介绍了细颗粒泥沙絮凝 -分散对土壤渗透性、土壤可蚀性以及污染物迁移的影响 ,以期有效防治水土流失和由此带来的非点源污染。

有机质、CaCl_2和MgCl_2对细颗粒泥沙絮凝沉降的影响

在CaCl2和MgCl2浓度为0~1.0mmol/L,泥沙浓度为10g/L时,用吸管法研究了有机质、CaCl2和MgCl2对细颗粒泥沙静水絮凝沉降的影响,结果表明,去除有机质后,细颗粒泥沙絮凝沉降加快,其絮凝所需的最佳电解质浓度降低;CaCl2和MgCl2的絮凝能力无明显差异,有机质含量对其几乎没有影响;在相同盐度下,细颗粒泥沙的絮凝沉降速度随电解质摩尔浓度的增大而增大.

AlCl_3对细颗粒泥沙絮凝沉降的影响

铝类絮凝剂对细颗粒泥沙絮凝沉降有重要作用 ,常应用于浑水澄清、农业污水处理等研究中。在AlCl3 浓度为 0～ 1 7mmol/L ,泥沙浓度为 1 0g/L时 ,用吸管法研究了AlCl3 对细颗粒泥沙絮凝沉降的影响 ,结果表明 :在液面下同一深度 ,泥沙浓度随时间呈指数衰减 ;悬液经多次搅拌后再沉降 ,其沉速减缓 ;当AlCl3 浓度为 0 9～ 1 7mmol/L时 ,出现明显的清浑水交界面 ,交界面随时间等速下降 ,平均沉速为 4 75 6cm/min ,对应的絮团平均粒径为 0 0 31 5mm ;土娄土絮凝临界粒径为 0 0 2 7mm。

有机质对细颗粒泥沙静水絮凝沉降特性的影响

在CaCl2 和MgCl2 浓度为 0～ 1.0mmol L ,泥沙浓度为 10g L时 ,本文用吸管法研究了有机质对细颗粒泥沙絮凝沉降的影响 ,结果表明 :在液面下同一深度 ,有机质并不影响泥沙浓度随时间呈指数衰减的变化规律。但去除有机质后 ,细颗粒泥沙絮凝的最佳电解质浓度降低 ;对于相同的电解质浓度 ,其絮凝沉降加快 ,泥沙平均沉速明显增大

SUSPENDED SEDIMENT TRANSPORT IN THE OFFSHORE NEAR YANGTZE ESTUARY

Based on the Estuarine, Coastal and Ocean Modeling System with Sediments (ECOMSED) model, a 3-D hydrodynamic-transport numerical model was established for the offshore area near the Yangtze Estuary in the East China Sea. The hydrodynamic module was driven by tide and wind. Sediment module included sediment resuspension, transport and deposition of cohesive and non-cohesive sediment. The settling of cohesive sediment in the water column was modeled as a function of aggregation (flocculation) and deposition. The numerical results were compared with observation data for August, 2006. It shows that the sediment concentration reduces gradually from the seashore to the offshore area. Numerical results of concentration time series in the observation stations show two peaks and two valleys, according with the observation data. It is mainly affected by tidal current. The suspended sediment concentration is related to the tidal current during a tidal cycle, and the maximum concentration appears 1 h-4 h after the current maximum velocity has reached.

Recovery of protein from discharged wastewater during the production of chitin

Studies were carried out to optimize the conditions for the recovery of protein. The results showed that pH of 6.00 for wastewater, the dosage of 1% chitosan solution in 1% acetic acid aqueous solution of 2.0 ml for 50 ml wastewater and 1% FeCl3 aqueous solution of 2 ml for 50 ml wastewater, the flocculation time of 4.0 h were the optimal conditions for the recovery of protein. The obtained protein sediment contained abundant amino acids, especially isoleucine, methione and lysine that are absent in other protein resource. (c) 2007 Elsevier Ltd. All rights reserved.

膨胀土化学改性实验研究

Expansive soil is a kind of typical unsaturated soil with characteristics of high swelling-shrinking deformation, cracks and over consolidation. It is very harmful to civil engineering, As a new processing method deal with expansive soil, Chemistry treatment has widespread applied in developed countries such as Europe and America, and also gained remarkable result. Based on the embankment filling soil improving testing projects in Meng-Xin freeway, this paper proposed a new processing method to expansive soil embankment wrapped with PAS-treated soil, experimental study of expansive soil chemical improved by PAS is been carried out. The water content change is the external factor which causes expansive soil to have swelling-shrinkage deformation. this reflected that the soil body swelling-shrinkage characteristic mainly depends on its mineral ingredient and the soil-water mutual function. This paper takes expansive soil as one kind of ordinary high plastic clay from angle of clay-water mutual function explained the expansive soil swelling-shrinkage deformation mechanism on microscopic. And take this swelling-shrinkage mechanism as the master line, Cooperates with the China Academy of Chemistry, we developed the new method PAS treatment, trough ionic exchange, joint, package and flocculation, the stronger static electricity function weakened the level through adsorption and the stronger static electricity function, PAS can weakened the negative charge repulsion between levels, causes the electric potential to reduce, diffusion layer thickness to be thinner, and improves the water affinity performance of expansive soil effectively. Moreover the space network architecture compromised with PAS and soil enhanced the joint strength between the clay particles , enable the soil body to have comparatively high strength and the distortion rate. pointed proposed the PAS modified principle. Combine with the construction of experimented road, this paper sums up and presents the construction craft and technology requirement of PAS treatment to expansive soil embankment. Through many experimental studied the basic physical property, the intensity characteristic and water stability changes of expansive soil and PAS-treated soil. The results of study indicate that adding lime into the expansive soil can reduce the content of clay gain obviously, reduce the plasticity notably, increase the strength greatly, control the property of swelling and shrinking effectively, and can meliorate the stability of sucking water clearly. Simultaneity PAS don’t change the cultivate capacity of the soil, the modified slope of the embankment can adopt plant fixed slope method as ecology protection. Finally the processing effect of use different treatment has analyzed through numerical simulation, summarized the PAS chemical wrapping treatment process in the actual project application, and appraised its processing effect and the project efficiency. The research indicated that PAS chemical treatment is one effective method to improve expansive soil. Compare with long-distance replacement, especially in the high plastic expansive soil massive distribution area, PAS treatment has the very greatly economical superiority to be promoted. The study in the paper not only afforded technique method to Meng-Xin expressway construction but also important for improvement of the expressway construction theory in swelling soil areas. Key words: PAS; expansive soil; swelling-shrinkage deformation mechanism; wrapping embankment; chemical modified treatment.

Investigation of lactic acid bacteria mediated bioprotection with applications in cereal industry. Case-study: malting process

Antifungal compounds produced by Lactic acid bacteria (LAB) metabolites can be natural and reliable alternative for reducing fungal infections pre- and post-harvest with a multitude of additional advantages for cereal-base products. Toxigenic and spoilage fungi are responsible for numerous diseases and economic losses. This thesis includes an overview of the impact fungi have on aspects of the cereal food chain. The applicability of LAB in plant protection and cereal industry is discussed in detail. Specific case studies include Fusarium head blight, and the impact of fungi in the malting and baking industry. The impact of Fusarium culmorum infected raw barley on the final malt quality was part of the investigation. In vitro infected barley grains were fully characterized. The study showed that the germinative energy of infected barley grains decreased by 45% and grains accumulated 199 μg.kg-1 of deoxynivalenol (DON). Barley grains were subsequently malted and fully characterized. Fungal biomass increased during all stages of malting. Infected malt accumulated 8-times its DON concentration during malting. Infected malt grains revealed extreme structural changes due to proteolytic, (hemi)-cellulolytic and starch degrading activity of the fungi, this led to increased friability and fragmentation. Infected grains also had higher protease and β-glucanase activities, lower amylase activity, a greater proportion of free amino and soluble nitrogen, and a lower β-glucan content. Malt loss was over 27% higher in infected malt when compared to the control. The protein compositional changes and respective enzymatic activity of infected barley and respective malt were characterized using a wide range of methods. F. culmorum infected barley grains showed an increase in proteolytic activity and protein extractability. Several metabolic proteins decreased and increased at different rates during infection and malting, showing a complex F. culmorum infection interdependence. In vitro F. culmorum infected malt was used to produce lager beer to investigate changes caused by the fungi during the brewing processes and their effect on beer quality attributes. It was found, that the wort containing infected malt had a lower pH, a higher FAN, higher β-glucan and a 45% increase in the purging rate, and led to premature yeast flocculation. The beer produced with infected malt (IB) had also a significantly different amino acid profile. IB flavour characterization revealed a higher concentration of esters, fusel alcohols, fatty acids, ketones, and dimethylsulfide, and in particular, acetaldehyde, when compared to the control. IB had a greater proportion of Strecker aldehydes and Maillard products contributing to an increased beer staling character. IB resulted in a 67% darker colour with a trend to better foam stability. It was also found that 78% of the accumulated mycotoxin deoxynivalenol in the malt was transferred into beer. A LAB cell-freesupernatant (cfs), produced in wort-base substrate, was investigated for its ability to inhibit Fusarium growth during malting. Wort was a suitable substrate for LAB exhibiting antifungal activity. Lactobacillus amylovorus DSM19280 inhibited 104 spores.mL-1 for 7 days, after 120 h of fermentation, while Lactobacillus reuteri R29 inhibited 105 spores.mL-1 for 7 days, after 48 h of fermentation. Both LAB cfs had significant different organic acid profiles. Acid-base antifungal compounds were identified and, phenyllactic, hydroxy-phenyllactic, and benzoic acids were present in higher concentrations when compared to the control. A 3 °P wort substrate inoculated With L. reuteri R29 (cfs) was applied in malting and successfully inhibited Fusarium growth by 23%, and mycotoxin DON by 80%. Malt attributes resulted in highly modified grains, lower pH, higher colouration, and higher extract yield. The implementation of selected LAB producing antifungal compounds can be used successfully in the malting process to reduce mould growth and mycotoxin production.

Fate of organo-mineral particles in streams: Microbial degradation by streamwater & biofilm assemblages

Inland waters are of global biogeochemical importance. They receive carbon inputs of ~ 4.8 Pg C/ y of which, 12 % is buried, 18 % transported to the oceans, and 70 % supports aquatic secondary production. However, the mechanisms that determine the fate of organic matter (OM) in these systems are poorly defined. One aspect of this is the formation of organo-mineral complexes in aquatic systems and their potential as a route for OM transport and burial vs. their use as carbon (C) and nitrogen (N) sources within aquatic systems. Organo-mineral particles form by sorption of dissolved OM to freshly eroded mineral surfaces and may contribute to ecosystem-scale particulate OM fluxes. We experimentally tested the availability of mineral-sorbed OM as a C & N source for streamwater microbial assemblages and streambed biofilms. Organo-mineral particles were constructed in vitro by sorption of ¹³C:¹⁵N-labelled amino acids to hydrated kaolin particles, and microbial degradation of these particles compared with equivalent doses of ¹³C:¹⁵N-labelled free amino acids. Experiments were conducted in 120 ml mesocosms over 7 days using biofilms and water sampled from the Oberer Seebach stream (Austria). Each incubation experienced a 16:8 light:dark regime, with metabolism monitored via changes in oxygen concentrations between photoperiods. The relative fate of the organo-mineral particles was quantified by tracing the mineralization of the ¹³C and ¹⁵N labels and their incorporation into microbial biomass. Here we present the initial results of ¹³C-label mineralization, incorporation and retention within dissolved organic carbon pool. The results indicate that 514 (± 219) μmol/ mmol of the ¹³:¹⁵N labeled free amino acids were mineralized over the 7-day incubations. By contrast, 186 (± 97) μmol/ mmol of the mineral-sorbed amino acids were mineralized over a similar period. Thus, organo-mineral complexation reduced amino acid mineralization by ~ 60 %, with no differences observed between the streamwater and biofilm assemblages. Throughout the incubations, biofilms were observed to leach dissolved organic carbon (DOC). However, within the streamwater assemblage the presence of both organo-mineral particles and kaolin particles was associated with significant DOC removal (-1.7 % and -7.5 % respectively). Consequently, the study demonstrates that mineral and organo-mineral particles can limit the availability of DOC in aquatic systems, providing nucleation sites for flocculation and fresh mineral surfaces, which facilitate OM-sorption. The formation of these organo-mineral particles subsequently restricts microbial OM degradation, potentially altering the transport and facilitating the burial of OM within streams.

Propriedades de lamas de salinas de Aveiro, tendo em vista aplicações dermoterapêuticas e dermocosméticas

Desde tempos históricos que diferentes tipos de lama são utilizados para aplicações externas no corpo humano, para fins terapêuticos e cosméticos. As lamas cuja beneficiação e caracterização físico-química são apresentadas nesta dissertação são formadas no ambiente hipersalino que existe nas salinas da Troncalhada e de São Tiago da Fonte, localizadas no estuário do rio Vouga, em Aveiro, Portugal. As salinas são constituídas por uma sequência de tanques onde, no período de verão, da água do mar e por evaporação natural, se produz sal marinho que precipita no último tanque (o cristalizador) do qual é extraído. Na base dos tanques ocorrem lamas que correspondem a sedimentos constituídos por material argiloso de cor preto-cinzento e que incorporam argila, silte, areia, bioclastos, sal, matéria orgânica e gás. A componente inorgânica da lama extraída do cristalizador foi estudada por Difracção de Raios-X (DRX) e Fluorescência de Raios-X (FRX), enquanto a componente orgânica da mesma lama foi estudada por Cromatografia de Gás- Espectrometria de Massa (GC-MS). Os estudos efectuados incidiram sobre amostras representativas de lama, obtidas antes e após refinação e beneficiação a que foi submetida a lama tal-qual colhida nas salinas. Foram utilizados métodos geofísicos para caracterizar e distinguir as lamas depositadas na época de safra e no período de interregno. Para o efeito, foram cravados tubos amostradores no sedimento que reveste o fundo dos tanques, tubos que seguidamente foram transportados para o laboratório para medição da condutividade eléctrica do topo até à base da coluna de sedimento amostrado. A refinação foi efectuada por elutriação de suspensões aquosas de lama utilizando um equipamento desenvolvido para o efeito e que permitiu concentrar a lama fina no overflow. Após floculação, sifonagem da água sobrenadante, dessalinização e centrifugação a lama refinada e beneficiada pôde ser incorporada em formulações com objectivos terapêuticos e cosméticos. O estudo microbiológico efectuado nas amostras de lama com sal e sem sal e na água das salinas permitiu identificar diversos tipos de bactérias e colónias presentes na lama e avaliar também os processos de esterilização testados. Concluiu-se que a lama hipersalina ou dessalinizada resultante do processamento a que foram submetidas, não deve ser aplicada ou incorporada em formulações tal-qual, pelo facto de em ambas terem sido identificadas bactérias como é o caso de Clostridium perfringens. Não obstante, se submetidas a esterilização utilizando autoclave a lama salina refinada e beneficiada poderá ser aplicada como peloide extemporâneo. Assim sendo foram desenvolvidas formulações dermoterapêuticas e dermocosméticas contendo lama beneficiada e dessalinizada e esterilizada termicamente.

Cleanup of industrial effluents containing heavy metals: a new opportunity of valorising the biomass produced by brewing industry

Heavy metal pollution is a matter of concern in industrialised countries. Contrary to organic pollutants, heavy metals are not metabolically degraded. This fact has two main consequences: its bioremediation requires another strategy and heavy metals can be indefinitely recycled. Yeast cells of Saccharomyces cerevisiae are produced at high amounts as a by-product of brewing industry constituting a cheap raw material. In the present work, the possibility of valorising this type of biomass in the bioremediation of real industrial effluents containing heavy metals is reviewed. Given the autoaggregation capacity (flocculation) of brewing yeast cells, a fast and off-cost yeast separation is achieved after the treatment of metal-laden effluent, which reduces the costs associated with the process. This is a critical issue when we are looking for an effective, eco-friendly, and low-cost technology. The possibility of the bioremediation of industrial effluents linked with the selective recovery of metals, in a strategy of simultaneous minimisation of environmental hazard of industrial wastes with financial benefits from reselling or recycling the metals, is discussed.