HDPE Enclosed Anaerobic Lagoon type of Digester, membrane material is HDPE(High Density Polyethylene), is a kind of cheap solution for anaerobic fermentation.

Structural features are as follows:
This kind of digester is a regular trapezoidal lagoon; Lagoon surface and bottom are rectangular (Surface is large, bottom is small); The trapezoidal slope is designed at generally 30 degrees to 45 Degrees according to actual volume of lagoon.The bottom of lagoon is anti-seepage treated by using HDPE geo-membrane in conformance to USA GRI quality standard and ASTM testing standards. Membrane thickness is mostly at 1.0 mm;The top of lagoon is covered by HDPE geo-membrane with the same standards as above, and a certain volume of space reserved for biogas storage, about 3~4 meters higher above ground level of lagoon when it's full of biogas. Membrane thickness is mostly at 1.5 mm;Stirring and TS% regulation of feedstock are implemented before fed into lagoon. Wells for pipeline, waste input&output, digestate discharging are distributed around the lagoon. Stirring mechanism,heating devices,pumps,Pipeline,Valves and Connections are embedded underground. Biogas pipe would be fixed on the outer HDPE membrane;The packaged HDPE membrane is rolled with 6~8 meters width, thermowelding process on site to make individual piece of membrane welded together. The foundation of lagoon would pressed tightly, and make sure that no sharp objects to damage the membrane. The top membrane is fixed tightly by using special anchoring devices.
Because of its following characteristics, the HDPE M.E.A.L has been widely spreading internationally, especially in Southeast Asia, South America and Africa:
Low construction cost, less investment, average cost per m³ is about US$ 4~10;Construction is simple, convenient with short installation time;Long HRT(Hydraulic Retention Time) and WRT(Waste Retention Time), high COD/BOD removal rate,resulting in clean liquid output;HDPE membrane has good heat absorption performance to cause high gas production, especially for areas with high ambient temperature.Large storage volume, all-in-one solution for fermentation and biogas storage;No limits by the structure, single lagoon volume can be up to 60,000 cubic meters;Low operating costs, low power consumption, simple operation.
Commonly Dimensions:

Comments:
The above dimensions would be changed without notice and Bigger dimensional lagoons are available.