J.P.M. Ploegaert

StalSens-Oren: meetsystemen voor bedrijfs-monitoring van emissies in de veehouderij : deskstudie naar de mogelijkheden voor directe emissieregistratie

Regulations on emissions of ammonia, fine dust and odour from livestock barns are based on emission factors of specified housing systems derived from field testing programmes of prototypes. Compliance with emission regulations is verified by inspection on the presence of specified housing systems on farms. An alternative regulatory approach is to rely on a farm based monitoring system that allows farmers to comply with a specified emission target by mitigation measures of their own choice. To enable this approach the development of a reliable and cost affordable farm monitoring system is needed. This report provides an overview of current technical options and perspectives for development, as well as a list of requirements that farm monitoring systems for emissions would need to meet.

Emissie van stikstofverbindingen uit luchtwassers met biologische wasstap

In de regel wordt aangenomen dat in luchtwassers met een biologische behandelingsstap ammoniak uit stallucht wordt omgezet in nitraat en nitriet, dat vervolgens met het spuiwater wordt afgevoerd. Er zijn echter aanwijzingen dat onder bepaalde condities (grote) hoeveelheden andere gasvormige stikstofverbindingen kunnen ontstaan en emitteren. Uit de steekproef die is uitgevoerd, blijkt dat bij biologische luchtwassers met een lage pH (<6,5) grote hoeveelheden stikstofoxyden (NOy) kunnen ontwijken naar de lucht. Voor dergelijk luchtwassers is de netto stikstofverwijdering veel lager dan de ammoniakverwijdering---In a biotrickling filter treating animal house exhaust air, ammonia is usually converted to dissolved nitrite and nitrate and subsequently removed with the discharge water. However, under certain operating conditions other types of gaseous nitrogen compounds may be emitted to the air. From the survey that was conducted it follows that at low pH values (<6.5) large amounts of gaseous nitrogen oxides (NOy) may be emitted from biotrickling filters. As a result, the net nitrogen removal of these scrubbers is much lower than the ammonia removal efficiency

Mathematical performance analysis of a temperature controlled bulk storage room

Usually, control design takes place after the plant has been designed. However, the performance of the plant connected to the controller might be improved by simultaneous design of the plant and the controller. In this paper, expressions are deduced that describe the dynamics of a controlled plant (a bulk storage room) and its design criteria. These expressions contain all the physical system parameters, and give insight on how the system performance (in terms of energy usage and temperature uniformity) depends on the design parameters (these are the bulk height and the ventilator- and heat exchanger capacity). This insight gives guidelines for optimal storage room design. The physical relations that could not be found in the literature were identified experimentally.