Assessment of the technological reliability of a hybrid constructed wetland for wastewater treatment in a mountain eco-tourist farm in Poland

Abstract

The aim of the present study was to assess the technological reliability of a domestic hybrid wastewater treatment installation consisting of a classic three-chambered (volume 6 m) septic tank, a vertical flow trickling bed filled with granules of a calcinated clay material (KERAMZYT), a special wetland bed constructed on a slope, and a permeable pond used as a receiver. The test treatment plant was located at a mountain eco-tourist farm on the periphery of the spa municipality of Krynica-Zdrój, Poland. The plant's operational reliability in reducing the concentration of organic matter, measured as biochemical oxygen demand (BOD) and chemical oxygen demand (COD), was 100% when modelled by both the Weibull and the lognormal distributions. The respective reliability values for total nitrogen removal were 76.8% and 77.0%, total suspended solids - 99.5% and 92.6%, and PO-P - 98.2% and 95.2%, with the differences being negligible. The installation was characterized by a very high level of technological reliability when compared with other solutions of this type. The Weibull method employed for statistical evaluation of technological reliability can also be used for comparison purposes. From the ecological perspective, the facility presented in the study has proven to be an effective tool for protecting local aquifer areas.

The Efficiency and Reliability of Pollutant Removal in a Hybrid Constructed Wetland with Common Reed, Manna Grass, and Virginia Mallow

“…Pollutant removal reliability values were assessed for the basic indicators of pollution (BOD 5 , COD, TSS, total nitrogen, and total phosphorus) using elements of Weibull's reliability theory. The Weibull distribution is a useful, general probability distribution, applicable in reliability tests and in assessment of the risk of exceeding the permissible values of pollution indicators in treated wastewater [8,[33][34][35]. It is characterized by the following probability density function:…”

“…As a result, the values of pollution parameters obtained at the outflow from the treatment plant were many times lower than admissible, which was also reflected in high levels of technological reliability. Hybrid systems were shown, among others, by Jucherski et al [35] and Jóźwiakowski [68] to be highly reliable in reducing the levels of BOD 5 and COD. In addition, in the studies of Jucherski et al [35], the reliabilities of total nitrogen and total phosphorus removal in hybrid constructed wetland systems were 76.8% and 95.2%, respectively.…”

“…Hybrid systems were shown, among others, by Jucherski et al [35] and Jóźwiakowski [68] to be highly reliable in reducing the levels of BOD 5 and COD. In addition, in the studies of Jucherski et al [35], the reliabilities of total nitrogen and total phosphorus removal in hybrid constructed wetland systems were 76.8% and 95.2%, respectively. To compare, in sewage treatment plants using conventional treatment methods (activated sludge, trickling filter, or hybrid reactor), the reliability of organic pollutants removal was in the range of 60-88% for BOD 5 and 89-96% for COD [7,33,69,70].…”

Reliability of removal of selected pollutants in different technological solutions of household wastewater treatment plants

“…The quality of fit of the Weibull distribution to empirical data was assessed by Hollander-Proschan test for the significant level of 0.05. The reliability function R(x) was calculated as a complement to the cumulative distribution function using the Equation 1 [BUGAJSKI et al 2012;JUCHERSKI et al 2017]:…”

Analysis of efficiency of phosphates sorption by different granulation of selected reactive material

“…Most often the small wastewater treatment plants may discharge to the receivers wastewater purified insufficiently. The solution may be the use of filtration materials in domestic wastewater treatment plants and constructed wetlands [3,4].…”