Biomedical subjects

H F van der Roest

Publications and source records attributed to H F van der Roest.

3 recordsLinked to original sources

PubMed2005

Boosting nitrification with the BABE technology.

Over the past years there has been a growing interest for compact, simple, low cost and robust technologies to upgrade wastewater treatment plants for nitrogen removal. The BABE (Bio Augmentation Batch Enhanced) technology is such a new concept. This patented system for biological treatment of sludge liquor - the effluent produced from digested sludge - uses a new principle, boosting the nitrifying bacteria in a side stream in such a way that the activated sludge in the main process is augmented. This augmentation increases the nitrification capacity of the wastewater treatment plant (wwtp). Experiments on a practical scale have demonstrated the effective and stable operation of the BABE technology. Model studies supported by the results of the full-scale tests showed that the technology can be applied in several situations, i.e. 1) introducing nitrification at high loaded wwtps; 2) enhancing nitrification at wwtps with incomplete nitrification; 3) enlarging denitrification at wwtps with complete nitrification. Most likely this year a full-scale application will be realized in the Netherlands at a wwtp with insufficient nitrification throughout the year.

Ammonia↗

PubMed2004

Full-scale application of the BABE technology.

Bio-augmentation can be used to obtain nitrification in activated sludge processes that operate at sub-optimal solid retention times. A side-stream process, the so-called BABE process that incorporates N-removal and augmentation of nitrifiers has been developed. The principle is to implement a nitrification reactor in the sludge return line, the so-called BABE reactor. This reactor can be fed with an internal N-rich flow (e.g. effluent from the sludge treatment). Hence the nitrification capacity of an activated sludge process can be augmented by the addition of nitrifiers cultivated in the BABE reactor. A full-scale test of the BABE technology has been at the treatment plant Garmerwolde in Groningen, the Netherlands. The set-up allowed comparing between three different lines: with the BABE reactor, without rejectwater and with untreated rejectwater. Based on this, the two important tasks (N-removal and inoculation) performed by the BABE reactor could be quantified. The results of the practical work in Garmerwolde showed a higher nitrification rate in the water line where the BABE reactor was implemented and also lower effluent ammonia. The experiments on a practical scale have demonstrated univocally the effective and stable operation of the BABE technology. In addition, sludge samples in different streams as well as from the BABE reactor were analysed with FISH technique. The FISH results illustrated the augmentation effect of the BABE reactor on the stream with the BABE reactor. A mathematical model, based on ASM1 model and implemented in AQUASIM was developed and used for simulating the treatment plant of Garmerwolde. The simulation results indicated that better effect of the BABE technology is expected at lower ambient temperatures and smaller volume of the BABE reactor. The BABE reactor could also allow for providing more space for de-nitrification in the main water line when nitrification is efficient enough.

Ammonia↗

PubMed2002

MBR-technology in municipal wastewater treatment: challenging the traditional treatment technologies.

In The Netherlands a development programme for the application of the MBR technology in municipal wastewater treatment has started. This paper briefly describes this development programme and goes into detail for the first step: a large pilot plant study at the Beverwijk WWTP. Under the supervision of DHV Water four different membrane systems from Kubota, Mitsubishi, X-Flow and Zenon were extensively tested. The objectives set for the study were more than achieved. The available world knowledge regarding municipal MBR was extremely limited and often very specific for a particular country's wastewater and wastewater flow characteristic. The conditions set by the Dutch situation were the first of its kind and lead to new methods of MBR optimisation. After almost two years of intensive research and further development of the technological feasibility of the MBR for The Netherlands, it has been decided to extend it to demonstration scale.

Bioreactors↗