Simultaneously Recovery of Phosphorus and Potassium Using Bubble Column Reactor as Struvite-K and Implementation on Crop Growth

Abstract

Struvite-K, similar to NH4-struvite with a composition of Mg:K:P (1:1:1). It is called struvite-K because the K replaces the NH4 in struvite. The composition usually used as fertilizer and can be recycling from wastewater including livestock wastewaters. In addition, Struvite-K which tends to form scale on surfaces of equipment which problem in many industries. The present study was used bubble column reactor which simple and efficient. In addition, the process can be implementation in wastewater industry which low-tech processes. Then, the struvite-K precipitate was implementation on crop growth which compared with coffee husk compost. The results show the removal of P via struvite-K showed 98.5% with the precipitation Mg:P of 0.7 and K:P of 1 with yields of 11.28 gram. Increases of magnesium dosage which decreases of P removal rate and affected of crystal size structure. Compost and struvite-K have similar positive impact on crop growth of (radish and komatsuna) were compared than control. In the other hand, the struvite-K is more effective than compost. This might be indicated that struvite-K is more slow-release nutrient than compost and higher macro nutrient supplied on soil which crop needed.

Is K-Struvite Precipitation a Plausible Nutrient Recovery Method from Potassium-Containing Wastes?—A Review

“…Therefore, the selection of the reactor type and optimization of its operational conditions are of importance in achieving large MPP crystal sizes with a good settling character that yield a higher process performance. Within this context, various types of reactors such as stirred-tank reactors (STRs) [17,23], fluidized bed reactors (FBRs) [30,67], a draft tube and baffle reactor (DTBR), [29,75] and a bubble column reactor with draft tube (BCRDT) [15,50] have been developed for MPP crystallization (Table S1).…”

“…An increase in the interface of the reaction zone was also observed for an excess amount of slurry. A bubble column with draft tube reactor was the reactor type utilized for simultaneous K and P recovery in some studies [50,15]. The shear stress and adhesion of particles to the surfaces in a BCRDT are lower than those produced in mechanical stirring because fluid circulation is provided by means of the pressure difference created by the air fed into the draft tube.…”

“…The shear stress and adhesion of particles to the surfaces in a BCRDT are lower than those produced in mechanical stirring because fluid circulation is provided by means of the pressure difference created by the air fed into the draft tube. Although the capability of such a reactor in the recovery of nutrients from livestock water drainage [50] and SPS [15] has been reported, no information on its operational conditions or associated problems were available in the relevant literature.…”

“…Hidayat et al [15] implemented a K-struvite precipitate on crop growth and compared it to a coffee-husk compost and unfertilized soil. Struvite produced from synthetic wastewater in a bubble column reactor was more effective in the growth of radish (Raphanus sativus L.) and komatsuna (Japanese mustard spinach) when compared to control and compost.…”

“…The other benefits of the process are protection from environmental pollution, particularly prevention of eutrophication, and a contribution to sustainability through a lesser use of phosphate resources [1]. All the above considerations apply to the case of the precipitation of the analogous magnesium potassium phosphate (MgKPO 4 •6H 2 O; MPP), which also produces a valuable substance with two fundamental elements (potassium and phosphate) for plant growth [15]. MPP precipitation is particularly advantageous because it is the only method to selectively remove, recover, and reuse potassium that has hitherto been supplied by natural resources in fertilizing activities [16].…”