Maturity of compost in terms of biochemical activity is assayed by self-heating experiments using Dewar-vessels (TMECC 2001, LAGA M10, 1995). The method is well standardized and resulting temperature readings lead to a value classified on a five level scale. The microbial decomposition of organic matter yields autothermic effects on temperature, which feed back to the activity pattern. Characteristic curves of temperature activity functions of the biological processes were evaluated quantitatively by means of an empirical algorithm. Systematic errors occurred, when assays were performed in Dewars of different size or at several packing densities and humidities of the compost. The vessels were described as heat conduction calorimeters that show characteristic functions of heat transfer. Modeling the process confirmed experimental results and demonstrated a transition to disproportional temperature activity relations of the system, which depended on the size of the Dewar vessel. Combining the algorithms of the biological process and the reactor yielded an instrument that allowed thorough ascertainments of sensitivity towards experimental conditions.

Composting of organic wastes saves environmental resources and helps to recover valuable constituents for agricultural purposes. Composting is a large scale bioprocess, which inherently is operated unisothermally for reasons of large scale and high oxidative metabolic activity. The autothermal pattern of internal heat generation affects the microbiology during the process. In this paper we demonstrate the impact of calorimetric approaches to composting in the laboratory and deduced implications for large scale installations, where oxygen supply, mass balances and heat dissipation calls for a thorough understanding. A comprehensive characterization of a lab-scale composting reactor was performed and the results and methodology transferred to the plant scale. Using these tools we estimated oxycaloric coefficients and mass to enthalpy ratios. Calorimetry provided a robust and reliable tool to study the bulk-kinetics of composting.

Im November 1995 wurden an 28 Standorten im Raum Kiel sowie einem Referenzstandort (Belauer See, ca. 20 km südlich von Kiel) die Blei-, Cadmium-, Kupfer- und Zinkgehalte in Regenwürmern der Art Aporrectodea caliginosa ermittelt und mit den Bodengehalten der Standorte verglichen. Für Blei und Kupfer konnte eine positive Korrelation zwischen den Wurm- und Bodengehalten festgestellt werden. Der Bleigehalt in den Regenwürmern war aber nicht nur von den Bodengehalten, sondern auch von deren pH-Werten und Calciumgehalten abhängig. Die Kupfergehalte nahmen mit zunehmendem Wurmgewicht exponentiell ab. Anhand der Blei-, Cadmium- und Kupfergehalte von A. caliginosa konnte ein Einfluß der Bodenbelastung Kiels auf die Schwermetallgehalte der Würmer festgestellt werden. Nach einer Einteilung der Wurmgehalte in Belastungsklassen ergab sich für die Stadt Kiel eine geringe bis mittlere Belastungssituation bezüglich der untersuchten Schwermetalle. Heavy metal content in Aporrectodea caliginosa (Oligochaeta, Lumbricidae) in the city of Kiel (Germany, Schleswig-Holstein) In November 1995 the content of lead, cadmium, copper and zinc in earthworms of the Aporrectodea caliginosa species was investigated at 28 sites of the Kiel area, as well as at one reference site (Belauer See, ca. 20 kilometres south of Kiel), and compared with the heavy metal content in the soil taken from all those sites. As for the lead and copper content, a positive correlation could be established between the earthworms and the soil. However, the lead content in the earthworms did not depend only on its amount in the soil, but also on soil pH and calcium content. Their copper content decreased exponentially as weight increased. The content of lead, cadmium and copper in A. caliginosa suggested an influence of urban soil pollution on the heavy metal content in earthworms. According to the grouping of heavy metal content in the earthworms, which was done in the course of the research work, the city of Kiel ranges among a minor to a medium degree of pollution caused by the investigated heavy metals.

The biosorption of heavy metal ions has attracted serious attention as a biotechnological approach to the removal of these elements from effluents or to the recovery of precious metals and radionuclides. We compared the metal sequestering capability of Bacillus subtilis, Saccharomyces cerevisiae and other strains, and determined sorption equilibria of the reaction M + L ⇄ ML and the corresponding heats of reaction. The strains showed typical capacities and affinities to a series of metal ions but no clear selectivities. Adsorption was slightly endothermic and very fast and was driven by large TΔS contributions. The data provide a critical view of the technical applicability of biosorption.

Microbial cultures were cultivated on the surface of glass beads inside the measuring cell of an isoperibolic twin-cell calorimeter in order to monitor microbial activity continuously. The system was applied to obtain an on-line estimation of the biological oxygen demand (BOD) of aqueous samples. Characteristics of this system are discussed concerning the feasibility of continuous calorimetric determinations of BOD. Growth kinetics and mass balances of attached microbial growth are too complicated to allow the assumption of a simple stoichiometric metabolism of a particular substrate as expected from the concept of the fully established BOD5-assay.

Chemie Ingenieur TechnikVolume 62, Issue 7 p. 582-583 Wissenschaftliche Forschungsarbeit Abtrennung von Schwermetallen aus Abwasserströmen – Biosorption im Vergleich zu herkömmlichen Verfahren Dipl.-Ing. Markus Röhricht, Dipl.-Ing. Markus Röhricht GBF – Gesellschaft für Biotechnologische Forschung mbH, Mascheroder Weg 1, 3300 BraunschweigSearch for more papers by this authorDr. Peter Weppen, Dr. Peter Weppen GBF – Gesellschaft für Biotechnologische Forschung mbH, Mascheroder Weg 1, 3300 BraunschweigSearch for more papers by this authorProf. Dr. Wolf-Dieter Deckwer, Prof. Dr. Wolf-Dieter Deckwer GBF – Gesellschaft für Biotechnologische Forschung mbH, Mascheroder Weg 1, 3300 BraunschweigSearch for more papers by this author Dipl.-Ing. Markus Röhricht, Dipl.-Ing. Markus Röhricht GBF – Gesellschaft für Biotechnologische Forschung mbH, Mascheroder Weg 1, 3300 BraunschweigSearch for more papers by this authorDr. Peter Weppen, Dr. Peter Weppen GBF – Gesellschaft für Biotechnologische Forschung mbH, Mascheroder Weg 1, 3300 BraunschweigSearch for more papers by this authorProf. Dr. Wolf-Dieter Deckwer, Prof. Dr. Wolf-Dieter Deckwer GBF – Gesellschaft für Biotechnologische Forschung mbH, Mascheroder Weg 1, 3300 BraunschweigSearch for more papers by this author First published: July 1990 https://doi.org/10.1002/cite.330620721Citations: 5AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onEmailFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Literatur 1 Malle, K.: Wasser, Luft Betr. 12 (1986) S. 46/49. Google Scholar 2 Brauckmann, B.: Umwelt (1987) Nr. 9, S. 461/463. Google Scholar 3 Volesky, B.: Removal and recovery of metals by biosorbent materials, Biotec 2 (1988), Eds. C. P. Hollenberg und H. Sahm, S. 135/149. Google Scholar 4 US-Pat. 320 093 (Volesky, 1982), EP 8310713-7.8 (De Voe, 1984), US-Pat. 4690894 (AMT, 1987), P 3901217.4 (GBF, 1989). Google Scholar 5 Daginnus, K.; Weppen, P.; Deckwer, W.-D.: Veröffentlichung in Vorbereitung, 1990. Google Scholar Citing Literature Volume62, Issue7July 1990Pages 582-583 ReferencesRelatedInformation

AbstractTechnologies for the clean‐up of soil contamination and older burdens. Older burdens as a consequence of fast industrialization and soil contamination by leakage and accidents require fast clean‐up. Sealing measures and storage on disposal sites postpone solution of the problem to some day in the future. Thermal treatment and washing entail extensive earth‐moving operations. They have a high energy requirement and are expensive. Microbiological processes presently under development are expected to yield less expensive solutions. The degradation properties of soil microflora or specially cultured microorganisms are exploited for this purpose. Treatment of lower‐lying contamination requires an adequate oxygen supply at the site of action.

Direct calorimetry was used to measure the metabolic heat production of Eschericnia coli growing on a synthetic culture medium. The principle of the chemostat culture allowed to change the growth conditions of the population easily and well reproducible. The steady-state growth rate of the cultures altered significantly the response of heat-flow rates and energy balances when toxic chemicals were added to the cultures. So we found a more pronounced increase of the heat flow after the addition of low concentrations of uncoupling agents at lower dilution-rates than at higher ones. The performance of our investigations was based almost on the properties of a specially designed heat-conduction-twin-calorimeter which containes the growing cultures directly inside its measuring cells.

Direct calorimetry is a superior technique in the field of bioenergetics. It is used to measure the metabolic heat production rate of chemostat-cultures of the bacterium Acinetobacter calcoaceticus. The heat production of these cultures normally remains constant as a consequence of steady-state conditions. The constancy is disturbed if poisonous substances are added to the culture. This effect disappears some time later and the initial steady state is recovered.