If you want to reduce costs, ...

If you want to reduce costs, then you should move away from mechanical methods. Mechanical systems can be effective, but at the same time they have high operational costs (use of chemicals, high power consumption, needs for specialized staff) and high maintenance needs. I have been working since many years on a green technology for sludge dewatering and drying; sludge treatment wetlands. In these systems, sludge dewatering takes place through natural processes only mediated by the presence of reeds, no use of chemicals is required, while power is only consumed for the distribution of sludge on the bed surface. It can even run without a permanent staff; regular inspection of the facility is adequate eg every 2-3 weeks. You have continuous loadings with sludge for many years, without the need to transport the dry solids on a daily basis to a landfill for final disposal. After few years of operation, the residual sludge layer that is built within the system is removed and then a new loading cycle beginns. The removed biosolids are digested material and they can be reuse eg in agriculture. The main concern with these systems is that they require higher land than mechanical systems. But they provide many benefits, both financial and technical, while the use of a green technology such as sludge treatment wetland promotes sustainability and the green corporate profile.